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-rw-r--r--ipc/Makefile12
-rw-r--r--ipc/compat.c745
-rw-r--r--ipc/compat_mq.c151
-rw-r--r--ipc/ipc_sysctl.c248
-rw-r--r--ipc/ipcns_notifier.c92
-rw-r--r--ipc/mq_sysctl.c115
-rw-r--r--ipc/mqueue.c1302
-rw-r--r--ipc/msg.c944
-rw-r--r--ipc/msgutil.c144
-rw-r--r--ipc/namespace.c179
-rw-r--r--ipc/sem.c1695
-rw-r--r--ipc/shm.c1237
-rw-r--r--ipc/syscall.c99
-rw-r--r--ipc/util.c987
-rw-r--r--ipc/util.h178
15 files changed, 8128 insertions, 0 deletions
diff --git a/ipc/Makefile b/ipc/Makefile
new file mode 100644
index 00000000..9075e172
--- /dev/null
+++ b/ipc/Makefile
@@ -0,0 +1,12 @@
+#
+# Makefile for the linux ipc.
+#
+
+obj-$(CONFIG_SYSVIPC_COMPAT) += compat.o
+obj-$(CONFIG_SYSVIPC) += util.o msgutil.o msg.o sem.o shm.o ipcns_notifier.o syscall.o
+obj-$(CONFIG_SYSVIPC_SYSCTL) += ipc_sysctl.o
+obj_mq-$(CONFIG_COMPAT) += compat_mq.o
+obj-$(CONFIG_POSIX_MQUEUE) += mqueue.o msgutil.o $(obj_mq-y)
+obj-$(CONFIG_IPC_NS) += namespace.o
+obj-$(CONFIG_POSIX_MQUEUE_SYSCTL) += mq_sysctl.o
+
diff --git a/ipc/compat.c b/ipc/compat.c
new file mode 100644
index 00000000..a6df704f
--- /dev/null
+++ b/ipc/compat.c
@@ -0,0 +1,745 @@
+/*
+ * 32 bit compatibility code for System V IPC
+ *
+ * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>
+ * Copyright (C) 2000 VA Linux Co
+ * Copyright (C) 2000 Don Dugger <n0ano@valinux.com>
+ * Copyright (C) 2000 Hewlett-Packard Co.
+ * Copyright (C) 2000 David Mosberger-Tang <davidm@hpl.hp.com>
+ * Copyright (C) 2000 Gerhard Tonn (ton@de.ibm.com)
+ * Copyright (C) 2000-2002 Andi Kleen, SuSE Labs (x86-64 port)
+ * Copyright (C) 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2001 IBM
+ * Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Copyright (C) 2004 Arnd Bergmann (arnd@arndb.de)
+ *
+ * This code is collected from the versions for sparc64, mips64, s390x, ia64,
+ * ppc64 and x86_64, all of which are based on the original sparc64 version
+ * by Jakub Jelinek.
+ *
+ */
+#include <linux/compat.h>
+#include <linux/errno.h>
+#include <linux/highuid.h>
+#include <linux/init.h>
+#include <linux/msg.h>
+#include <linux/shm.h>
+#include <linux/syscalls.h>
+#include <linux/ptrace.h>
+
+#include <linux/mutex.h>
+#include <asm/uaccess.h>
+
+#include "util.h"
+
+struct compat_msgbuf {
+ compat_long_t mtype;
+ char mtext[1];
+};
+
+struct compat_ipc_perm {
+ key_t key;
+ __compat_uid_t uid;
+ __compat_gid_t gid;
+ __compat_uid_t cuid;
+ __compat_gid_t cgid;
+ compat_mode_t mode;
+ unsigned short seq;
+};
+
+struct compat_semid_ds {
+ struct compat_ipc_perm sem_perm;
+ compat_time_t sem_otime;
+ compat_time_t sem_ctime;
+ compat_uptr_t sem_base;
+ compat_uptr_t sem_pending;
+ compat_uptr_t sem_pending_last;
+ compat_uptr_t undo;
+ unsigned short sem_nsems;
+};
+
+struct compat_msqid_ds {
+ struct compat_ipc_perm msg_perm;
+ compat_uptr_t msg_first;
+ compat_uptr_t msg_last;
+ compat_time_t msg_stime;
+ compat_time_t msg_rtime;
+ compat_time_t msg_ctime;
+ compat_ulong_t msg_lcbytes;
+ compat_ulong_t msg_lqbytes;
+ unsigned short msg_cbytes;
+ unsigned short msg_qnum;
+ unsigned short msg_qbytes;
+ compat_ipc_pid_t msg_lspid;
+ compat_ipc_pid_t msg_lrpid;
+};
+
+struct compat_shmid_ds {
+ struct compat_ipc_perm shm_perm;
+ int shm_segsz;
+ compat_time_t shm_atime;
+ compat_time_t shm_dtime;
+ compat_time_t shm_ctime;
+ compat_ipc_pid_t shm_cpid;
+ compat_ipc_pid_t shm_lpid;
+ unsigned short shm_nattch;
+ unsigned short shm_unused;
+ compat_uptr_t shm_unused2;
+ compat_uptr_t shm_unused3;
+};
+
+struct compat_ipc_kludge {
+ compat_uptr_t msgp;
+ compat_long_t msgtyp;
+};
+
+struct compat_shminfo64 {
+ compat_ulong_t shmmax;
+ compat_ulong_t shmmin;
+ compat_ulong_t shmmni;
+ compat_ulong_t shmseg;
+ compat_ulong_t shmall;
+ compat_ulong_t __unused1;
+ compat_ulong_t __unused2;
+ compat_ulong_t __unused3;
+ compat_ulong_t __unused4;
+};
+
+struct compat_shm_info {
+ compat_int_t used_ids;
+ compat_ulong_t shm_tot, shm_rss, shm_swp;
+ compat_ulong_t swap_attempts, swap_successes;
+};
+
+extern int sem_ctls[];
+#define sc_semopm (sem_ctls[2])
+
+static inline int compat_ipc_parse_version(int *cmd)
+{
+#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
+ int version = *cmd & IPC_64;
+
+ /* this is tricky: architectures that have support for the old
+ * ipc structures in 64 bit binaries need to have IPC_64 set
+ * in cmd, the others need to have it cleared */
+#ifndef ipc_parse_version
+ *cmd |= IPC_64;
+#else
+ *cmd &= ~IPC_64;
+#endif
+ return version;
+#else
+ /* With the asm-generic APIs, we always use the 64-bit versions. */
+ return IPC_64;
+#endif
+}
+
+static inline int __get_compat_ipc64_perm(struct ipc64_perm *p64,
+ struct compat_ipc64_perm __user *up64)
+{
+ int err;
+
+ err = __get_user(p64->uid, &up64->uid);
+ err |= __get_user(p64->gid, &up64->gid);
+ err |= __get_user(p64->mode, &up64->mode);
+ return err;
+}
+
+static inline int __get_compat_ipc_perm(struct ipc64_perm *p,
+ struct compat_ipc_perm __user *up)
+{
+ int err;
+
+ err = __get_user(p->uid, &up->uid);
+ err |= __get_user(p->gid, &up->gid);
+ err |= __get_user(p->mode, &up->mode);
+ return err;
+}
+
+static inline int __put_compat_ipc64_perm(struct ipc64_perm *p64,
+ struct compat_ipc64_perm __user *up64)
+{
+ int err;
+
+ err = __put_user(p64->key, &up64->key);
+ err |= __put_user(p64->uid, &up64->uid);
+ err |= __put_user(p64->gid, &up64->gid);
+ err |= __put_user(p64->cuid, &up64->cuid);
+ err |= __put_user(p64->cgid, &up64->cgid);
+ err |= __put_user(p64->mode, &up64->mode);
+ err |= __put_user(p64->seq, &up64->seq);
+ return err;
+}
+
+static inline int __put_compat_ipc_perm(struct ipc64_perm *p,
+ struct compat_ipc_perm __user *up)
+{
+ int err;
+ __compat_uid_t u;
+ __compat_gid_t g;
+
+ err = __put_user(p->key, &up->key);
+ SET_UID(u, p->uid);
+ err |= __put_user(u, &up->uid);
+ SET_GID(g, p->gid);
+ err |= __put_user(g, &up->gid);
+ SET_UID(u, p->cuid);
+ err |= __put_user(u, &up->cuid);
+ SET_GID(g, p->cgid);
+ err |= __put_user(g, &up->cgid);
+ err |= __put_user(p->mode, &up->mode);
+ err |= __put_user(p->seq, &up->seq);
+ return err;
+}
+
+static inline int get_compat_semid64_ds(struct semid64_ds *s64,
+ struct compat_semid64_ds __user *up64)
+{
+ if (!access_ok (VERIFY_READ, up64, sizeof(*up64)))
+ return -EFAULT;
+ return __get_compat_ipc64_perm(&s64->sem_perm, &up64->sem_perm);
+}
+
+static inline int get_compat_semid_ds(struct semid64_ds *s,
+ struct compat_semid_ds __user *up)
+{
+ if (!access_ok (VERIFY_READ, up, sizeof(*up)))
+ return -EFAULT;
+ return __get_compat_ipc_perm(&s->sem_perm, &up->sem_perm);
+}
+
+static inline int put_compat_semid64_ds(struct semid64_ds *s64,
+ struct compat_semid64_ds __user *up64)
+{
+ int err;
+
+ if (!access_ok (VERIFY_WRITE, up64, sizeof(*up64)))
+ return -EFAULT;
+ err = __put_compat_ipc64_perm(&s64->sem_perm, &up64->sem_perm);
+ err |= __put_user(s64->sem_otime, &up64->sem_otime);
+ err |= __put_user(s64->sem_ctime, &up64->sem_ctime);
+ err |= __put_user(s64->sem_nsems, &up64->sem_nsems);
+ return err;
+}
+
+static inline int put_compat_semid_ds(struct semid64_ds *s,
+ struct compat_semid_ds __user *up)
+{
+ int err;
+
+ if (!access_ok (VERIFY_WRITE, up, sizeof(*up)))
+ return -EFAULT;
+ err = __put_compat_ipc_perm(&s->sem_perm, &up->sem_perm);
+ err |= __put_user(s->sem_otime, &up->sem_otime);
+ err |= __put_user(s->sem_ctime, &up->sem_ctime);
+ err |= __put_user(s->sem_nsems, &up->sem_nsems);
+ return err;
+}
+
+static long do_compat_semctl(int first, int second, int third, u32 pad)
+{
+ union semun fourth;
+ int err, err2;
+ struct semid64_ds s64;
+ struct semid64_ds __user *up64;
+ int version = compat_ipc_parse_version(&third);
+
+ memset(&s64, 0, sizeof(s64));
+
+ if ((third & (~IPC_64)) == SETVAL)
+ fourth.val = (int) pad;
+ else
+ fourth.__pad = compat_ptr(pad);
+ switch (third & (~IPC_64)) {
+ case IPC_INFO:
+ case IPC_RMID:
+ case SEM_INFO:
+ case GETVAL:
+ case GETPID:
+ case GETNCNT:
+ case GETZCNT:
+ case GETALL:
+ case SETVAL:
+ case SETALL:
+ err = sys_semctl(first, second, third, fourth);
+ break;
+
+ case IPC_STAT:
+ case SEM_STAT:
+ up64 = compat_alloc_user_space(sizeof(s64));
+ fourth.__pad = up64;
+ err = sys_semctl(first, second, third, fourth);
+ if (err < 0)
+ break;
+ if (copy_from_user(&s64, up64, sizeof(s64)))
+ err2 = -EFAULT;
+ else if (version == IPC_64)
+ err2 = put_compat_semid64_ds(&s64, compat_ptr(pad));
+ else
+ err2 = put_compat_semid_ds(&s64, compat_ptr(pad));
+ if (err2)
+ err = -EFAULT;
+ break;
+
+ case IPC_SET:
+ if (version == IPC_64) {
+ err = get_compat_semid64_ds(&s64, compat_ptr(pad));
+ } else {
+ err = get_compat_semid_ds(&s64, compat_ptr(pad));
+ }
+ up64 = compat_alloc_user_space(sizeof(s64));
+ if (copy_to_user(up64, &s64, sizeof(s64)))
+ err = -EFAULT;
+ if (err)
+ break;
+
+ fourth.__pad = up64;
+ err = sys_semctl(first, second, third, fourth);
+ break;
+
+ default:
+ err = -EINVAL;
+ break;
+ }
+ return err;
+}
+
+#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
+long compat_sys_semctl(int first, int second, int third, void __user *uptr)
+{
+ u32 pad;
+
+ if (!uptr)
+ return -EINVAL;
+ if (get_user(pad, (u32 __user *) uptr))
+ return -EFAULT;
+ return do_compat_semctl(first, second, third, pad);
+}
+
+long compat_sys_msgsnd(int first, int second, int third, void __user *uptr)
+{
+ struct compat_msgbuf __user *up = uptr;
+ long type;
+
+ if (first < 0)
+ return -EINVAL;
+ if (second < 0)
+ return -EINVAL;
+
+ if (get_user(type, &up->mtype))
+ return -EFAULT;
+
+ return do_msgsnd(first, type, up->mtext, second, third);
+}
+
+long compat_sys_msgrcv(int first, int second, int msgtyp, int third,
+ int version, void __user *uptr)
+{
+ struct compat_msgbuf __user *up;
+ long type;
+ int err;
+
+ if (first < 0)
+ return -EINVAL;
+ if (second < 0)
+ return -EINVAL;
+
+ if (!version) {
+ struct compat_ipc_kludge ipck;
+ err = -EINVAL;
+ if (!uptr)
+ goto out;
+ err = -EFAULT;
+ if (copy_from_user (&ipck, uptr, sizeof(ipck)))
+ goto out;
+ uptr = compat_ptr(ipck.msgp);
+ msgtyp = ipck.msgtyp;
+ }
+ up = uptr;
+ err = do_msgrcv(first, &type, up->mtext, second, msgtyp, third);
+ if (err < 0)
+ goto out;
+ if (put_user(type, &up->mtype))
+ err = -EFAULT;
+out:
+ return err;
+}
+#else
+long compat_sys_semctl(int semid, int semnum, int cmd, int arg)
+{
+ return do_compat_semctl(semid, semnum, cmd, arg);
+}
+
+long compat_sys_msgsnd(int msqid, struct compat_msgbuf __user *msgp,
+ size_t msgsz, int msgflg)
+{
+ compat_long_t mtype;
+
+ if (get_user(mtype, &msgp->mtype))
+ return -EFAULT;
+ return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
+}
+
+long compat_sys_msgrcv(int msqid, struct compat_msgbuf __user *msgp,
+ size_t msgsz, long msgtyp, int msgflg)
+{
+ long err, mtype;
+
+ err = do_msgrcv(msqid, &mtype, msgp->mtext, msgsz, msgtyp, msgflg);
+ if (err < 0)
+ goto out;
+
+ if (put_user(mtype, &msgp->mtype))
+ err = -EFAULT;
+ out:
+ return err;
+}
+#endif
+
+static inline int get_compat_msqid64(struct msqid64_ds *m64,
+ struct compat_msqid64_ds __user *up64)
+{
+ int err;
+
+ if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
+ return -EFAULT;
+ err = __get_compat_ipc64_perm(&m64->msg_perm, &up64->msg_perm);
+ err |= __get_user(m64->msg_qbytes, &up64->msg_qbytes);
+ return err;
+}
+
+static inline int get_compat_msqid(struct msqid64_ds *m,
+ struct compat_msqid_ds __user *up)
+{
+ int err;
+
+ if (!access_ok(VERIFY_READ, up, sizeof(*up)))
+ return -EFAULT;
+ err = __get_compat_ipc_perm(&m->msg_perm, &up->msg_perm);
+ err |= __get_user(m->msg_qbytes, &up->msg_qbytes);
+ return err;
+}
+
+static inline int put_compat_msqid64_ds(struct msqid64_ds *m64,
+ struct compat_msqid64_ds __user *up64)
+{
+ int err;
+
+ if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
+ return -EFAULT;
+ err = __put_compat_ipc64_perm(&m64->msg_perm, &up64->msg_perm);
+ err |= __put_user(m64->msg_stime, &up64->msg_stime);
+ err |= __put_user(m64->msg_rtime, &up64->msg_rtime);
+ err |= __put_user(m64->msg_ctime, &up64->msg_ctime);
+ err |= __put_user(m64->msg_cbytes, &up64->msg_cbytes);
+ err |= __put_user(m64->msg_qnum, &up64->msg_qnum);
+ err |= __put_user(m64->msg_qbytes, &up64->msg_qbytes);
+ err |= __put_user(m64->msg_lspid, &up64->msg_lspid);
+ err |= __put_user(m64->msg_lrpid, &up64->msg_lrpid);
+ return err;
+}
+
+static inline int put_compat_msqid_ds(struct msqid64_ds *m,
+ struct compat_msqid_ds __user *up)
+{
+ int err;
+
+ if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
+ return -EFAULT;
+ err = __put_compat_ipc_perm(&m->msg_perm, &up->msg_perm);
+ err |= __put_user(m->msg_stime, &up->msg_stime);
+ err |= __put_user(m->msg_rtime, &up->msg_rtime);
+ err |= __put_user(m->msg_ctime, &up->msg_ctime);
+ err |= __put_user(m->msg_cbytes, &up->msg_cbytes);
+ err |= __put_user(m->msg_qnum, &up->msg_qnum);
+ err |= __put_user(m->msg_qbytes, &up->msg_qbytes);
+ err |= __put_user(m->msg_lspid, &up->msg_lspid);
+ err |= __put_user(m->msg_lrpid, &up->msg_lrpid);
+ return err;
+}
+
+long compat_sys_msgctl(int first, int second, void __user *uptr)
+{
+ int err, err2;
+ struct msqid64_ds m64;
+ int version = compat_ipc_parse_version(&second);
+ void __user *p;
+
+ memset(&m64, 0, sizeof(m64));
+
+ switch (second & (~IPC_64)) {
+ case IPC_INFO:
+ case IPC_RMID:
+ case MSG_INFO:
+ err = sys_msgctl(first, second, uptr);
+ break;
+
+ case IPC_SET:
+ if (version == IPC_64) {
+ err = get_compat_msqid64(&m64, uptr);
+ } else {
+ err = get_compat_msqid(&m64, uptr);
+ }
+ if (err)
+ break;
+ p = compat_alloc_user_space(sizeof(m64));
+ if (copy_to_user(p, &m64, sizeof(m64)))
+ err = -EFAULT;
+ else
+ err = sys_msgctl(first, second, p);
+ break;
+
+ case IPC_STAT:
+ case MSG_STAT:
+ p = compat_alloc_user_space(sizeof(m64));
+ err = sys_msgctl(first, second, p);
+ if (err < 0)
+ break;
+ if (copy_from_user(&m64, p, sizeof(m64)))
+ err2 = -EFAULT;
+ else if (version == IPC_64)
+ err2 = put_compat_msqid64_ds(&m64, uptr);
+ else
+ err2 = put_compat_msqid_ds(&m64, uptr);
+ if (err2)
+ err = -EFAULT;
+ break;
+
+ default:
+ err = -EINVAL;
+ break;
+ }
+ return err;
+}
+
+#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
+long compat_sys_shmat(int first, int second, compat_uptr_t third, int version,
+ void __user *uptr)
+{
+ int err;
+ unsigned long raddr;
+ compat_ulong_t __user *uaddr;
+
+ if (version == 1)
+ return -EINVAL;
+ err = do_shmat(first, uptr, second, &raddr);
+ if (err < 0)
+ return err;
+ uaddr = compat_ptr(third);
+ return put_user(raddr, uaddr);
+}
+#else
+long compat_sys_shmat(int shmid, compat_uptr_t shmaddr, int shmflg)
+{
+ unsigned long ret;
+ long err;
+
+ err = do_shmat(shmid, compat_ptr(shmaddr), shmflg, &ret);
+ if (err)
+ return err;
+ force_successful_syscall_return();
+ return (long)ret;
+}
+#endif
+
+static inline int get_compat_shmid64_ds(struct shmid64_ds *s64,
+ struct compat_shmid64_ds __user *up64)
+{
+ if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
+ return -EFAULT;
+ return __get_compat_ipc64_perm(&s64->shm_perm, &up64->shm_perm);
+}
+
+static inline int get_compat_shmid_ds(struct shmid64_ds *s,
+ struct compat_shmid_ds __user *up)
+{
+ if (!access_ok(VERIFY_READ, up, sizeof(*up)))
+ return -EFAULT;
+ return __get_compat_ipc_perm(&s->shm_perm, &up->shm_perm);
+}
+
+static inline int put_compat_shmid64_ds(struct shmid64_ds *s64,
+ struct compat_shmid64_ds __user *up64)
+{
+ int err;
+
+ if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
+ return -EFAULT;
+ err = __put_compat_ipc64_perm(&s64->shm_perm, &up64->shm_perm);
+ err |= __put_user(s64->shm_atime, &up64->shm_atime);
+ err |= __put_user(s64->shm_dtime, &up64->shm_dtime);
+ err |= __put_user(s64->shm_ctime, &up64->shm_ctime);
+ err |= __put_user(s64->shm_segsz, &up64->shm_segsz);
+ err |= __put_user(s64->shm_nattch, &up64->shm_nattch);
+ err |= __put_user(s64->shm_cpid, &up64->shm_cpid);
+ err |= __put_user(s64->shm_lpid, &up64->shm_lpid);
+ return err;
+}
+
+static inline int put_compat_shmid_ds(struct shmid64_ds *s,
+ struct compat_shmid_ds __user *up)
+{
+ int err;
+
+ if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
+ return -EFAULT;
+ err = __put_compat_ipc_perm(&s->shm_perm, &up->shm_perm);
+ err |= __put_user(s->shm_atime, &up->shm_atime);
+ err |= __put_user(s->shm_dtime, &up->shm_dtime);
+ err |= __put_user(s->shm_ctime, &up->shm_ctime);
+ err |= __put_user(s->shm_segsz, &up->shm_segsz);
+ err |= __put_user(s->shm_nattch, &up->shm_nattch);
+ err |= __put_user(s->shm_cpid, &up->shm_cpid);
+ err |= __put_user(s->shm_lpid, &up->shm_lpid);
+ return err;
+}
+
+static inline int put_compat_shminfo64(struct shminfo64 *smi,
+ struct compat_shminfo64 __user *up64)
+{
+ int err;
+
+ if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
+ return -EFAULT;
+ if (smi->shmmax > INT_MAX)
+ smi->shmmax = INT_MAX;
+ err = __put_user(smi->shmmax, &up64->shmmax);
+ err |= __put_user(smi->shmmin, &up64->shmmin);
+ err |= __put_user(smi->shmmni, &up64->shmmni);
+ err |= __put_user(smi->shmseg, &up64->shmseg);
+ err |= __put_user(smi->shmall, &up64->shmall);
+ return err;
+}
+
+static inline int put_compat_shminfo(struct shminfo64 *smi,
+ struct shminfo __user *up)
+{
+ int err;
+
+ if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
+ return -EFAULT;
+ if (smi->shmmax > INT_MAX)
+ smi->shmmax = INT_MAX;
+ err = __put_user(smi->shmmax, &up->shmmax);
+ err |= __put_user(smi->shmmin, &up->shmmin);
+ err |= __put_user(smi->shmmni, &up->shmmni);
+ err |= __put_user(smi->shmseg, &up->shmseg);
+ err |= __put_user(smi->shmall, &up->shmall);
+ return err;
+}
+
+static inline int put_compat_shm_info(struct shm_info __user *ip,
+ struct compat_shm_info __user *uip)
+{
+ int err;
+ struct shm_info si;
+
+ if (!access_ok(VERIFY_WRITE, uip, sizeof(*uip)) ||
+ copy_from_user(&si, ip, sizeof(si)))
+ return -EFAULT;
+ err = __put_user(si.used_ids, &uip->used_ids);
+ err |= __put_user(si.shm_tot, &uip->shm_tot);
+ err |= __put_user(si.shm_rss, &uip->shm_rss);
+ err |= __put_user(si.shm_swp, &uip->shm_swp);
+ err |= __put_user(si.swap_attempts, &uip->swap_attempts);
+ err |= __put_user(si.swap_successes, &uip->swap_successes);
+ return err;
+}
+
+long compat_sys_shmctl(int first, int second, void __user *uptr)
+{
+ void __user *p;
+ struct shmid64_ds s64;
+ struct shminfo64 smi;
+ int err, err2;
+ int version = compat_ipc_parse_version(&second);
+
+ memset(&s64, 0, sizeof(s64));
+
+ switch (second & (~IPC_64)) {
+ case IPC_RMID:
+ case SHM_LOCK:
+ case SHM_UNLOCK:
+ err = sys_shmctl(first, second, uptr);
+ break;
+
+ case IPC_INFO:
+ p = compat_alloc_user_space(sizeof(smi));
+ err = sys_shmctl(first, second, p);
+ if (err < 0)
+ break;
+ if (copy_from_user(&smi, p, sizeof(smi)))
+ err2 = -EFAULT;
+ else if (version == IPC_64)
+ err2 = put_compat_shminfo64(&smi, uptr);
+ else
+ err2 = put_compat_shminfo(&smi, uptr);
+ if (err2)
+ err = -EFAULT;
+ break;
+
+
+ case IPC_SET:
+ if (version == IPC_64) {
+ err = get_compat_shmid64_ds(&s64, uptr);
+ } else {
+ err = get_compat_shmid_ds(&s64, uptr);
+ }
+ if (err)
+ break;
+ p = compat_alloc_user_space(sizeof(s64));
+ if (copy_to_user(p, &s64, sizeof(s64)))
+ err = -EFAULT;
+ else
+ err = sys_shmctl(first, second, p);
+ break;
+
+ case IPC_STAT:
+ case SHM_STAT:
+ p = compat_alloc_user_space(sizeof(s64));
+ err = sys_shmctl(first, second, p);
+ if (err < 0)
+ break;
+ if (copy_from_user(&s64, p, sizeof(s64)))
+ err2 = -EFAULT;
+ else if (version == IPC_64)
+ err2 = put_compat_shmid64_ds(&s64, uptr);
+ else
+ err2 = put_compat_shmid_ds(&s64, uptr);
+ if (err2)
+ err = -EFAULT;
+ break;
+
+ case SHM_INFO:
+ p = compat_alloc_user_space(sizeof(struct shm_info));
+ err = sys_shmctl(first, second, p);
+ if (err < 0)
+ break;
+ err2 = put_compat_shm_info(p, uptr);
+ if (err2)
+ err = -EFAULT;
+ break;
+
+ default:
+ err = -EINVAL;
+ break;
+ }
+ return err;
+}
+
+long compat_sys_semtimedop(int semid, struct sembuf __user *tsems,
+ unsigned nsops, const struct compat_timespec __user *timeout)
+{
+ struct timespec __user *ts64 = NULL;
+ if (timeout) {
+ struct timespec ts;
+ ts64 = compat_alloc_user_space(sizeof(*ts64));
+ if (get_compat_timespec(&ts, timeout))
+ return -EFAULT;
+ if (copy_to_user(ts64, &ts, sizeof(ts)))
+ return -EFAULT;
+ }
+ return sys_semtimedop(semid, tsems, nsops, ts64);
+}
diff --git a/ipc/compat_mq.c b/ipc/compat_mq.c
new file mode 100644
index 00000000..380ea4fe
--- /dev/null
+++ b/ipc/compat_mq.c
@@ -0,0 +1,151 @@
+/*
+ * ipc/compat_mq.c
+ * 32 bit emulation for POSIX message queue system calls
+ *
+ * Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Author: Arnd Bergmann <arnd@arndb.de>
+ */
+
+#include <linux/compat.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/mqueue.h>
+#include <linux/syscalls.h>
+
+#include <asm/uaccess.h>
+
+struct compat_mq_attr {
+ compat_long_t mq_flags; /* message queue flags */
+ compat_long_t mq_maxmsg; /* maximum number of messages */
+ compat_long_t mq_msgsize; /* maximum message size */
+ compat_long_t mq_curmsgs; /* number of messages currently queued */
+ compat_long_t __reserved[4]; /* ignored for input, zeroed for output */
+};
+
+static inline int get_compat_mq_attr(struct mq_attr *attr,
+ const struct compat_mq_attr __user *uattr)
+{
+ if (!access_ok(VERIFY_READ, uattr, sizeof *uattr))
+ return -EFAULT;
+
+ return __get_user(attr->mq_flags, &uattr->mq_flags)
+ | __get_user(attr->mq_maxmsg, &uattr->mq_maxmsg)
+ | __get_user(attr->mq_msgsize, &uattr->mq_msgsize)
+ | __get_user(attr->mq_curmsgs, &uattr->mq_curmsgs);
+}
+
+static inline int put_compat_mq_attr(const struct mq_attr *attr,
+ struct compat_mq_attr __user *uattr)
+{
+ if (clear_user(uattr, sizeof *uattr))
+ return -EFAULT;
+
+ return __put_user(attr->mq_flags, &uattr->mq_flags)
+ | __put_user(attr->mq_maxmsg, &uattr->mq_maxmsg)
+ | __put_user(attr->mq_msgsize, &uattr->mq_msgsize)
+ | __put_user(attr->mq_curmsgs, &uattr->mq_curmsgs);
+}
+
+asmlinkage long compat_sys_mq_open(const char __user *u_name,
+ int oflag, compat_mode_t mode,
+ struct compat_mq_attr __user *u_attr)
+{
+ void __user *p = NULL;
+ if (u_attr && oflag & O_CREAT) {
+ struct mq_attr attr;
+
+ memset(&attr, 0, sizeof(attr));
+
+ p = compat_alloc_user_space(sizeof(attr));
+ if (get_compat_mq_attr(&attr, u_attr) ||
+ copy_to_user(p, &attr, sizeof(attr)))
+ return -EFAULT;
+ }
+ return sys_mq_open(u_name, oflag, mode, p);
+}
+
+static int compat_prepare_timeout(struct timespec __user * *p,
+ const struct compat_timespec __user *u)
+{
+ struct timespec ts;
+ if (!u) {
+ *p = NULL;
+ return 0;
+ }
+ *p = compat_alloc_user_space(sizeof(ts));
+ if (get_compat_timespec(&ts, u) || copy_to_user(*p, &ts, sizeof(ts)))
+ return -EFAULT;
+ return 0;
+}
+
+asmlinkage long compat_sys_mq_timedsend(mqd_t mqdes,
+ const char __user *u_msg_ptr,
+ size_t msg_len, unsigned int msg_prio,
+ const struct compat_timespec __user *u_abs_timeout)
+{
+ struct timespec __user *u_ts;
+
+ if (compat_prepare_timeout(&u_ts, u_abs_timeout))
+ return -EFAULT;
+
+ return sys_mq_timedsend(mqdes, u_msg_ptr, msg_len,
+ msg_prio, u_ts);
+}
+
+asmlinkage ssize_t compat_sys_mq_timedreceive(mqd_t mqdes,
+ char __user *u_msg_ptr,
+ size_t msg_len, unsigned int __user *u_msg_prio,
+ const struct compat_timespec __user *u_abs_timeout)
+{
+ struct timespec __user *u_ts;
+ if (compat_prepare_timeout(&u_ts, u_abs_timeout))
+ return -EFAULT;
+
+ return sys_mq_timedreceive(mqdes, u_msg_ptr, msg_len,
+ u_msg_prio, u_ts);
+}
+
+asmlinkage long compat_sys_mq_notify(mqd_t mqdes,
+ const struct compat_sigevent __user *u_notification)
+{
+ struct sigevent __user *p = NULL;
+ if (u_notification) {
+ struct sigevent n;
+ p = compat_alloc_user_space(sizeof(*p));
+ if (get_compat_sigevent(&n, u_notification))
+ return -EFAULT;
+ if (n.sigev_notify == SIGEV_THREAD)
+ n.sigev_value.sival_ptr = compat_ptr(n.sigev_value.sival_int);
+ if (copy_to_user(p, &n, sizeof(*p)))
+ return -EFAULT;
+ }
+ return sys_mq_notify(mqdes, p);
+}
+
+asmlinkage long compat_sys_mq_getsetattr(mqd_t mqdes,
+ const struct compat_mq_attr __user *u_mqstat,
+ struct compat_mq_attr __user *u_omqstat)
+{
+ struct mq_attr mqstat;
+ struct mq_attr __user *p = compat_alloc_user_space(2 * sizeof(*p));
+ long ret;
+
+ memset(&mqstat, 0, sizeof(mqstat));
+
+ if (u_mqstat) {
+ if (get_compat_mq_attr(&mqstat, u_mqstat) ||
+ copy_to_user(p, &mqstat, sizeof(mqstat)))
+ return -EFAULT;
+ }
+ ret = sys_mq_getsetattr(mqdes,
+ u_mqstat ? p : NULL,
+ u_omqstat ? p + 1 : NULL);
+ if (ret)
+ return ret;
+ if (u_omqstat) {
+ if (copy_from_user(&mqstat, p + 1, sizeof(mqstat)) ||
+ put_compat_mq_attr(&mqstat, u_omqstat))
+ return -EFAULT;
+ }
+ return 0;
+}
diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c
new file mode 100644
index 00000000..00fba2ba
--- /dev/null
+++ b/ipc/ipc_sysctl.c
@@ -0,0 +1,248 @@
+/*
+ * Copyright (C) 2007
+ *
+ * Author: Eric Biederman <ebiederm@xmision.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#include <linux/module.h>
+#include <linux/ipc.h>
+#include <linux/nsproxy.h>
+#include <linux/sysctl.h>
+#include <linux/uaccess.h>
+#include <linux/ipc_namespace.h>
+#include <linux/msg.h>
+#include "util.h"
+
+static void *get_ipc(ctl_table *table)
+{
+ char *which = table->data;
+ struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
+ which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
+ return which;
+}
+
+#ifdef CONFIG_PROC_SYSCTL
+static int proc_ipc_dointvec(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table ipc_table;
+
+ memcpy(&ipc_table, table, sizeof(ipc_table));
+ ipc_table.data = get_ipc(table);
+
+ return proc_dointvec(&ipc_table, write, buffer, lenp, ppos);
+}
+
+static int proc_ipc_dointvec_minmax(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table ipc_table;
+
+ memcpy(&ipc_table, table, sizeof(ipc_table));
+ ipc_table.data = get_ipc(table);
+
+ return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
+}
+
+static int proc_ipc_dointvec_minmax_orphans(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ipc_namespace *ns = current->nsproxy->ipc_ns;
+ int err = proc_ipc_dointvec_minmax(table, write, buffer, lenp, ppos);
+
+ if (err < 0)
+ return err;
+ if (ns->shm_rmid_forced)
+ shm_destroy_orphaned(ns);
+ return err;
+}
+
+static int proc_ipc_callback_dointvec(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table ipc_table;
+ size_t lenp_bef = *lenp;
+ int rc;
+
+ memcpy(&ipc_table, table, sizeof(ipc_table));
+ ipc_table.data = get_ipc(table);
+
+ rc = proc_dointvec(&ipc_table, write, buffer, lenp, ppos);
+
+ if (write && !rc && lenp_bef == *lenp)
+ /*
+ * Tunable has successfully been changed by hand. Disable its
+ * automatic adjustment. This simply requires unregistering
+ * the notifiers that trigger recalculation.
+ */
+ unregister_ipcns_notifier(current->nsproxy->ipc_ns);
+
+ return rc;
+}
+
+static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table ipc_table;
+ memcpy(&ipc_table, table, sizeof(ipc_table));
+ ipc_table.data = get_ipc(table);
+
+ return proc_doulongvec_minmax(&ipc_table, write, buffer,
+ lenp, ppos);
+}
+
+/*
+ * Routine that is called when the file "auto_msgmni" has successfully been
+ * written.
+ * Two values are allowed:
+ * 0: unregister msgmni's callback routine from the ipc namespace notifier
+ * chain. This means that msgmni won't be recomputed anymore upon memory
+ * add/remove or ipc namespace creation/removal.
+ * 1: register back the callback routine.
+ */
+static void ipc_auto_callback(int val)
+{
+ if (!val)
+ unregister_ipcns_notifier(current->nsproxy->ipc_ns);
+ else {
+ /*
+ * Re-enable automatic recomputing only if not already
+ * enabled.
+ */
+ recompute_msgmni(current->nsproxy->ipc_ns);
+ cond_register_ipcns_notifier(current->nsproxy->ipc_ns);
+ }
+}
+
+static int proc_ipcauto_dointvec_minmax(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table ipc_table;
+ size_t lenp_bef = *lenp;
+ int oldval;
+ int rc;
+
+ memcpy(&ipc_table, table, sizeof(ipc_table));
+ ipc_table.data = get_ipc(table);
+ oldval = *((int *)(ipc_table.data));
+
+ rc = proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
+
+ if (write && !rc && lenp_bef == *lenp) {
+ int newval = *((int *)(ipc_table.data));
+ /*
+ * The file "auto_msgmni" has correctly been set.
+ * React by (un)registering the corresponding tunable, if the
+ * value has changed.
+ */
+ if (newval != oldval)
+ ipc_auto_callback(newval);
+ }
+
+ return rc;
+}
+
+#else
+#define proc_ipc_doulongvec_minmax NULL
+#define proc_ipc_dointvec NULL
+#define proc_ipc_dointvec_minmax NULL
+#define proc_ipc_dointvec_minmax_orphans NULL
+#define proc_ipc_callback_dointvec NULL
+#define proc_ipcauto_dointvec_minmax NULL
+#endif
+
+static int zero;
+static int one = 1;
+
+static struct ctl_table ipc_kern_table[] = {
+ {
+ .procname = "shmmax",
+ .data = &init_ipc_ns.shm_ctlmax,
+ .maxlen = sizeof (init_ipc_ns.shm_ctlmax),
+ .mode = 0644,
+ .proc_handler = proc_ipc_doulongvec_minmax,
+ },
+ {
+ .procname = "shmall",
+ .data = &init_ipc_ns.shm_ctlall,
+ .maxlen = sizeof (init_ipc_ns.shm_ctlall),
+ .mode = 0644,
+ .proc_handler = proc_ipc_doulongvec_minmax,
+ },
+ {
+ .procname = "shmmni",
+ .data = &init_ipc_ns.shm_ctlmni,
+ .maxlen = sizeof (init_ipc_ns.shm_ctlmni),
+ .mode = 0644,
+ .proc_handler = proc_ipc_dointvec,
+ },
+ {
+ .procname = "shm_rmid_forced",
+ .data = &init_ipc_ns.shm_rmid_forced,
+ .maxlen = sizeof(init_ipc_ns.shm_rmid_forced),
+ .mode = 0644,
+ .proc_handler = proc_ipc_dointvec_minmax_orphans,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
+ {
+ .procname = "msgmax",
+ .data = &init_ipc_ns.msg_ctlmax,
+ .maxlen = sizeof (init_ipc_ns.msg_ctlmax),
+ .mode = 0644,
+ .proc_handler = proc_ipc_dointvec,
+ },
+ {
+ .procname = "msgmni",
+ .data = &init_ipc_ns.msg_ctlmni,
+ .maxlen = sizeof (init_ipc_ns.msg_ctlmni),
+ .mode = 0644,
+ .proc_handler = proc_ipc_callback_dointvec,
+ },
+ {
+ .procname = "msgmnb",
+ .data = &init_ipc_ns.msg_ctlmnb,
+ .maxlen = sizeof (init_ipc_ns.msg_ctlmnb),
+ .mode = 0644,
+ .proc_handler = proc_ipc_dointvec,
+ },
+ {
+ .procname = "sem",
+ .data = &init_ipc_ns.sem_ctls,
+ .maxlen = 4*sizeof (int),
+ .mode = 0644,
+ .proc_handler = proc_ipc_dointvec,
+ },
+ {
+ .procname = "auto_msgmni",
+ .data = &init_ipc_ns.auto_msgmni,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_ipcauto_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
+ {}
+};
+
+static struct ctl_table ipc_root_table[] = {
+ {
+ .procname = "kernel",
+ .mode = 0555,
+ .child = ipc_kern_table,
+ },
+ {}
+};
+
+static int __init ipc_sysctl_init(void)
+{
+ register_sysctl_table(ipc_root_table);
+ return 0;
+}
+
+__initcall(ipc_sysctl_init);
diff --git a/ipc/ipcns_notifier.c b/ipc/ipcns_notifier.c
new file mode 100644
index 00000000..b9b31a4f
--- /dev/null
+++ b/ipc/ipcns_notifier.c
@@ -0,0 +1,92 @@
+/*
+ * linux/ipc/ipcns_notifier.c
+ * Copyright (C) 2007 BULL SA. Nadia Derbey
+ *
+ * Notification mechanism for ipc namespaces:
+ * The callback routine registered in the memory chain invokes the ipcns
+ * notifier chain with the IPCNS_MEMCHANGED event.
+ * Each callback routine registered in the ipcns namespace recomputes msgmni
+ * for the owning namespace.
+ */
+
+#include <linux/msg.h>
+#include <linux/rcupdate.h>
+#include <linux/notifier.h>
+#include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
+
+#include "util.h"
+
+
+
+static BLOCKING_NOTIFIER_HEAD(ipcns_chain);
+
+
+static int ipcns_callback(struct notifier_block *self,
+ unsigned long action, void *arg)
+{
+ struct ipc_namespace *ns;
+
+ switch (action) {
+ case IPCNS_MEMCHANGED: /* amount of lowmem has changed */
+ case IPCNS_CREATED:
+ case IPCNS_REMOVED:
+ /*
+ * It's time to recompute msgmni
+ */
+ ns = container_of(self, struct ipc_namespace, ipcns_nb);
+ /*
+ * No need to get a reference on the ns: the 1st job of
+ * free_ipc_ns() is to unregister the callback routine.
+ * blocking_notifier_chain_unregister takes the wr lock to do
+ * it.
+ * When this callback routine is called the rd lock is held by
+ * blocking_notifier_call_chain.
+ * So the ipc ns cannot be freed while we are here.
+ */
+ recompute_msgmni(ns);
+ break;
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+int register_ipcns_notifier(struct ipc_namespace *ns)
+{
+ int rc;
+
+ memset(&ns->ipcns_nb, 0, sizeof(ns->ipcns_nb));
+ ns->ipcns_nb.notifier_call = ipcns_callback;
+ ns->ipcns_nb.priority = IPCNS_CALLBACK_PRI;
+ rc = blocking_notifier_chain_register(&ipcns_chain, &ns->ipcns_nb);
+ if (!rc)
+ ns->auto_msgmni = 1;
+ return rc;
+}
+
+int cond_register_ipcns_notifier(struct ipc_namespace *ns)
+{
+ int rc;
+
+ memset(&ns->ipcns_nb, 0, sizeof(ns->ipcns_nb));
+ ns->ipcns_nb.notifier_call = ipcns_callback;
+ ns->ipcns_nb.priority = IPCNS_CALLBACK_PRI;
+ rc = blocking_notifier_chain_cond_register(&ipcns_chain,
+ &ns->ipcns_nb);
+ if (!rc)
+ ns->auto_msgmni = 1;
+ return rc;
+}
+
+void unregister_ipcns_notifier(struct ipc_namespace *ns)
+{
+ blocking_notifier_chain_unregister(&ipcns_chain, &ns->ipcns_nb);
+ ns->auto_msgmni = 0;
+}
+
+int ipcns_notify(unsigned long val)
+{
+ return blocking_notifier_call_chain(&ipcns_chain, val, NULL);
+}
diff --git a/ipc/mq_sysctl.c b/ipc/mq_sysctl.c
new file mode 100644
index 00000000..0c09366b
--- /dev/null
+++ b/ipc/mq_sysctl.c
@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2007 IBM Corporation
+ *
+ * Author: Cedric Le Goater <clg@fr.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
+#include <linux/sysctl.h>
+
+/*
+ * Define the ranges various user-specified maximum values can
+ * be set to.
+ */
+#define MIN_MSGMAX 1 /* min value for msg_max */
+#define MAX_MSGMAX HARD_MSGMAX /* max value for msg_max */
+#define MIN_MSGSIZEMAX 128 /* min value for msgsize_max */
+#define MAX_MSGSIZEMAX (8192*128) /* max value for msgsize_max */
+
+#ifdef CONFIG_PROC_SYSCTL
+static void *get_mq(ctl_table *table)
+{
+ char *which = table->data;
+ struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
+ which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
+ return which;
+}
+
+static int proc_mq_dointvec(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table mq_table;
+ memcpy(&mq_table, table, sizeof(mq_table));
+ mq_table.data = get_mq(table);
+
+ return proc_dointvec(&mq_table, write, buffer, lenp, ppos);
+}
+
+static int proc_mq_dointvec_minmax(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table mq_table;
+ memcpy(&mq_table, table, sizeof(mq_table));
+ mq_table.data = get_mq(table);
+
+ return proc_dointvec_minmax(&mq_table, write, buffer,
+ lenp, ppos);
+}
+#else
+#define proc_mq_dointvec NULL
+#define proc_mq_dointvec_minmax NULL
+#endif
+
+static int msg_max_limit_min = MIN_MSGMAX;
+static int msg_max_limit_max = MAX_MSGMAX;
+
+static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
+static int msg_maxsize_limit_max = MAX_MSGSIZEMAX;
+
+static ctl_table mq_sysctls[] = {
+ {
+ .procname = "queues_max",
+ .data = &init_ipc_ns.mq_queues_max,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_mq_dointvec,
+ },
+ {
+ .procname = "msg_max",
+ .data = &init_ipc_ns.mq_msg_max,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_mq_dointvec_minmax,
+ .extra1 = &msg_max_limit_min,
+ .extra2 = &msg_max_limit_max,
+ },
+ {
+ .procname = "msgsize_max",
+ .data = &init_ipc_ns.mq_msgsize_max,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_mq_dointvec_minmax,
+ .extra1 = &msg_maxsize_limit_min,
+ .extra2 = &msg_maxsize_limit_max,
+ },
+ {}
+};
+
+static ctl_table mq_sysctl_dir[] = {
+ {
+ .procname = "mqueue",
+ .mode = 0555,
+ .child = mq_sysctls,
+ },
+ {}
+};
+
+static ctl_table mq_sysctl_root[] = {
+ {
+ .procname = "fs",
+ .mode = 0555,
+ .child = mq_sysctl_dir,
+ },
+ {}
+};
+
+struct ctl_table_header *mq_register_sysctl_table(void)
+{
+ return register_sysctl_table(mq_sysctl_root);
+}
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
new file mode 100644
index 00000000..28bd64dd
--- /dev/null
+++ b/ipc/mqueue.c
@@ -0,0 +1,1302 @@
+/*
+ * POSIX message queues filesystem for Linux.
+ *
+ * Copyright (C) 2003,2004 Krzysztof Benedyczak (golbi@mat.uni.torun.pl)
+ * Michal Wronski (michal.wronski@gmail.com)
+ *
+ * Spinlocks: Mohamed Abbas (abbas.mohamed@intel.com)
+ * Lockless receive & send, fd based notify:
+ * Manfred Spraul (manfred@colorfullife.com)
+ *
+ * Audit: George Wilson (ltcgcw@us.ibm.com)
+ *
+ * This file is released under the GPL.
+ */
+
+#include <linux/capability.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/file.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/sysctl.h>
+#include <linux/poll.h>
+#include <linux/mqueue.h>
+#include <linux/msg.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/syscalls.h>
+#include <linux/audit.h>
+#include <linux/signal.h>
+#include <linux/mutex.h>
+#include <linux/nsproxy.h>
+#include <linux/pid.h>
+#include <linux/ipc_namespace.h>
+#include <linux/user_namespace.h>
+#include <linux/slab.h>
+
+#include <net/sock.h>
+#include "util.h"
+
+#define MQUEUE_MAGIC 0x19800202
+#define DIRENT_SIZE 20
+#define FILENT_SIZE 80
+
+#define SEND 0
+#define RECV 1
+
+#define STATE_NONE 0
+#define STATE_PENDING 1
+#define STATE_READY 2
+
+struct ext_wait_queue { /* queue of sleeping tasks */
+ struct task_struct *task;
+ struct list_head list;
+ struct msg_msg *msg; /* ptr of loaded message */
+ int state; /* one of STATE_* values */
+};
+
+struct mqueue_inode_info {
+ spinlock_t lock;
+ struct inode vfs_inode;
+ wait_queue_head_t wait_q;
+
+ struct msg_msg **messages;
+ struct mq_attr attr;
+
+ struct sigevent notify;
+ struct pid* notify_owner;
+ struct user_struct *user; /* user who created, for accounting */
+ struct sock *notify_sock;
+ struct sk_buff *notify_cookie;
+
+ /* for tasks waiting for free space and messages, respectively */
+ struct ext_wait_queue e_wait_q[2];
+
+ unsigned long qsize; /* size of queue in memory (sum of all msgs) */
+};
+
+static const struct inode_operations mqueue_dir_inode_operations;
+static const struct file_operations mqueue_file_operations;
+static const struct super_operations mqueue_super_ops;
+static void remove_notification(struct mqueue_inode_info *info);
+
+static struct kmem_cache *mqueue_inode_cachep;
+
+static struct ctl_table_header * mq_sysctl_table;
+
+static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode)
+{
+ return container_of(inode, struct mqueue_inode_info, vfs_inode);
+}
+
+/*
+ * This routine should be called with the mq_lock held.
+ */
+static inline struct ipc_namespace *__get_ns_from_inode(struct inode *inode)
+{
+ return get_ipc_ns(inode->i_sb->s_fs_info);
+}
+
+static struct ipc_namespace *get_ns_from_inode(struct inode *inode)
+{
+ struct ipc_namespace *ns;
+
+ spin_lock(&mq_lock);
+ ns = __get_ns_from_inode(inode);
+ spin_unlock(&mq_lock);
+ return ns;
+}
+
+static struct inode *mqueue_get_inode(struct super_block *sb,
+ struct ipc_namespace *ipc_ns, umode_t mode,
+ struct mq_attr *attr)
+{
+ struct user_struct *u = current_user();
+ struct inode *inode;
+ int ret = -ENOMEM;
+
+ inode = new_inode(sb);
+ if (!inode)
+ goto err;
+
+ inode->i_ino = get_next_ino();
+ inode->i_mode = mode;
+ inode->i_uid = current_fsuid();
+ inode->i_gid = current_fsgid();
+ inode->i_mtime = inode->i_ctime = inode->i_atime = CURRENT_TIME;
+
+ if (S_ISREG(mode)) {
+ struct mqueue_inode_info *info;
+ unsigned long mq_bytes, mq_msg_tblsz;
+
+ inode->i_fop = &mqueue_file_operations;
+ inode->i_size = FILENT_SIZE;
+ /* mqueue specific info */
+ info = MQUEUE_I(inode);
+ spin_lock_init(&info->lock);
+ init_waitqueue_head(&info->wait_q);
+ INIT_LIST_HEAD(&info->e_wait_q[0].list);
+ INIT_LIST_HEAD(&info->e_wait_q[1].list);
+ info->notify_owner = NULL;
+ info->qsize = 0;
+ info->user = NULL; /* set when all is ok */
+ memset(&info->attr, 0, sizeof(info->attr));
+ info->attr.mq_maxmsg = ipc_ns->mq_msg_max;
+ info->attr.mq_msgsize = ipc_ns->mq_msgsize_max;
+ if (attr) {
+ info->attr.mq_maxmsg = attr->mq_maxmsg;
+ info->attr.mq_msgsize = attr->mq_msgsize;
+ }
+ mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *);
+ info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL);
+ if (!info->messages)
+ goto out_inode;
+
+ mq_bytes = (mq_msg_tblsz +
+ (info->attr.mq_maxmsg * info->attr.mq_msgsize));
+
+ spin_lock(&mq_lock);
+ if (u->mq_bytes + mq_bytes < u->mq_bytes ||
+ u->mq_bytes + mq_bytes > rlimit(RLIMIT_MSGQUEUE)) {
+ spin_unlock(&mq_lock);
+ /* mqueue_evict_inode() releases info->messages */
+ ret = -EMFILE;
+ goto out_inode;
+ }
+ u->mq_bytes += mq_bytes;
+ spin_unlock(&mq_lock);
+
+ /* all is ok */
+ info->user = get_uid(u);
+ } else if (S_ISDIR(mode)) {
+ inc_nlink(inode);
+ /* Some things misbehave if size == 0 on a directory */
+ inode->i_size = 2 * DIRENT_SIZE;
+ inode->i_op = &mqueue_dir_inode_operations;
+ inode->i_fop = &simple_dir_operations;
+ }
+
+ return inode;
+out_inode:
+ iput(inode);
+err:
+ return ERR_PTR(ret);
+}
+
+static int mqueue_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct inode *inode;
+ struct ipc_namespace *ns = data;
+
+ sb->s_blocksize = PAGE_CACHE_SIZE;
+ sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+ sb->s_magic = MQUEUE_MAGIC;
+ sb->s_op = &mqueue_super_ops;
+
+ inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO, NULL);
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
+
+ sb->s_root = d_make_root(inode);
+ if (!sb->s_root)
+ return -ENOMEM;
+ return 0;
+}
+
+static struct dentry *mqueue_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name,
+ void *data)
+{
+ if (!(flags & MS_KERNMOUNT))
+ data = current->nsproxy->ipc_ns;
+ return mount_ns(fs_type, flags, data, mqueue_fill_super);
+}
+
+static void init_once(void *foo)
+{
+ struct mqueue_inode_info *p = (struct mqueue_inode_info *) foo;
+
+ inode_init_once(&p->vfs_inode);
+}
+
+static struct inode *mqueue_alloc_inode(struct super_block *sb)
+{
+ struct mqueue_inode_info *ei;
+
+ ei = kmem_cache_alloc(mqueue_inode_cachep, GFP_KERNEL);
+ if (!ei)
+ return NULL;
+ return &ei->vfs_inode;
+}
+
+static void mqueue_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ kmem_cache_free(mqueue_inode_cachep, MQUEUE_I(inode));
+}
+
+static void mqueue_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, mqueue_i_callback);
+}
+
+static void mqueue_evict_inode(struct inode *inode)
+{
+ struct mqueue_inode_info *info;
+ struct user_struct *user;
+ unsigned long mq_bytes;
+ int i;
+ struct ipc_namespace *ipc_ns;
+
+ end_writeback(inode);
+
+ if (S_ISDIR(inode->i_mode))
+ return;
+
+ ipc_ns = get_ns_from_inode(inode);
+ info = MQUEUE_I(inode);
+ spin_lock(&info->lock);
+ for (i = 0; i < info->attr.mq_curmsgs; i++)
+ free_msg(info->messages[i]);
+ kfree(info->messages);
+ spin_unlock(&info->lock);
+
+ /* Total amount of bytes accounted for the mqueue */
+ mq_bytes = info->attr.mq_maxmsg * (sizeof(struct msg_msg *)
+ + info->attr.mq_msgsize);
+ user = info->user;
+ if (user) {
+ spin_lock(&mq_lock);
+ user->mq_bytes -= mq_bytes;
+ /*
+ * get_ns_from_inode() ensures that the
+ * (ipc_ns = sb->s_fs_info) is either a valid ipc_ns
+ * to which we now hold a reference, or it is NULL.
+ * We can't put it here under mq_lock, though.
+ */
+ if (ipc_ns)
+ ipc_ns->mq_queues_count--;
+ spin_unlock(&mq_lock);
+ free_uid(user);
+ }
+ if (ipc_ns)
+ put_ipc_ns(ipc_ns);
+}
+
+static int mqueue_create(struct inode *dir, struct dentry *dentry,
+ umode_t mode, struct nameidata *nd)
+{
+ struct inode *inode;
+ struct mq_attr *attr = dentry->d_fsdata;
+ int error;
+ struct ipc_namespace *ipc_ns;
+
+ spin_lock(&mq_lock);
+ ipc_ns = __get_ns_from_inode(dir);
+ if (!ipc_ns) {
+ error = -EACCES;
+ goto out_unlock;
+ }
+ if (ipc_ns->mq_queues_count >= ipc_ns->mq_queues_max &&
+ !capable(CAP_SYS_RESOURCE)) {
+ error = -ENOSPC;
+ goto out_unlock;
+ }
+ ipc_ns->mq_queues_count++;
+ spin_unlock(&mq_lock);
+
+ inode = mqueue_get_inode(dir->i_sb, ipc_ns, mode, attr);
+ if (IS_ERR(inode)) {
+ error = PTR_ERR(inode);
+ spin_lock(&mq_lock);
+ ipc_ns->mq_queues_count--;
+ goto out_unlock;
+ }
+
+ put_ipc_ns(ipc_ns);
+ dir->i_size += DIRENT_SIZE;
+ dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
+
+ d_instantiate(dentry, inode);
+ dget(dentry);
+ return 0;
+out_unlock:
+ spin_unlock(&mq_lock);
+ if (ipc_ns)
+ put_ipc_ns(ipc_ns);
+ return error;
+}
+
+static int mqueue_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+
+ dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
+ dir->i_size -= DIRENT_SIZE;
+ drop_nlink(inode);
+ dput(dentry);
+ return 0;
+}
+
+/*
+* This is routine for system read from queue file.
+* To avoid mess with doing here some sort of mq_receive we allow
+* to read only queue size & notification info (the only values
+* that are interesting from user point of view and aren't accessible
+* through std routines)
+*/
+static ssize_t mqueue_read_file(struct file *filp, char __user *u_data,
+ size_t count, loff_t *off)
+{
+ struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode);
+ char buffer[FILENT_SIZE];
+ ssize_t ret;
+
+ spin_lock(&info->lock);
+ snprintf(buffer, sizeof(buffer),
+ "QSIZE:%-10lu NOTIFY:%-5d SIGNO:%-5d NOTIFY_PID:%-6d\n",
+ info->qsize,
+ info->notify_owner ? info->notify.sigev_notify : 0,
+ (info->notify_owner &&
+ info->notify.sigev_notify == SIGEV_SIGNAL) ?
+ info->notify.sigev_signo : 0,
+ pid_vnr(info->notify_owner));
+ spin_unlock(&info->lock);
+ buffer[sizeof(buffer)-1] = '\0';
+
+ ret = simple_read_from_buffer(u_data, count, off, buffer,
+ strlen(buffer));
+ if (ret <= 0)
+ return ret;
+
+ filp->f_path.dentry->d_inode->i_atime = filp->f_path.dentry->d_inode->i_ctime = CURRENT_TIME;
+ return ret;
+}
+
+static int mqueue_flush_file(struct file *filp, fl_owner_t id)
+{
+ struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode);
+
+ spin_lock(&info->lock);
+ if (task_tgid(current) == info->notify_owner)
+ remove_notification(info);
+
+ spin_unlock(&info->lock);
+ return 0;
+}
+
+static unsigned int mqueue_poll_file(struct file *filp, struct poll_table_struct *poll_tab)
+{
+ struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode);
+ int retval = 0;
+
+ poll_wait(filp, &info->wait_q, poll_tab);
+
+ spin_lock(&info->lock);
+ if (info->attr.mq_curmsgs)
+ retval = POLLIN | POLLRDNORM;
+
+ if (info->attr.mq_curmsgs < info->attr.mq_maxmsg)
+ retval |= POLLOUT | POLLWRNORM;
+ spin_unlock(&info->lock);
+
+ return retval;
+}
+
+/* Adds current to info->e_wait_q[sr] before element with smaller prio */
+static void wq_add(struct mqueue_inode_info *info, int sr,
+ struct ext_wait_queue *ewp)
+{
+ struct ext_wait_queue *walk;
+
+ ewp->task = current;
+
+ list_for_each_entry(walk, &info->e_wait_q[sr].list, list) {
+ if (walk->task->static_prio <= current->static_prio) {
+ list_add_tail(&ewp->list, &walk->list);
+ return;
+ }
+ }
+ list_add_tail(&ewp->list, &info->e_wait_q[sr].list);
+}
+
+/*
+ * Puts current task to sleep. Caller must hold queue lock. After return
+ * lock isn't held.
+ * sr: SEND or RECV
+ */
+static int wq_sleep(struct mqueue_inode_info *info, int sr,
+ ktime_t *timeout, struct ext_wait_queue *ewp)
+{
+ int retval;
+ signed long time;
+
+ wq_add(info, sr, ewp);
+
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ spin_unlock(&info->lock);
+ time = schedule_hrtimeout_range_clock(timeout, 0,
+ HRTIMER_MODE_ABS, CLOCK_REALTIME);
+
+ while (ewp->state == STATE_PENDING)
+ cpu_relax();
+
+ if (ewp->state == STATE_READY) {
+ retval = 0;
+ goto out;
+ }
+ spin_lock(&info->lock);
+ if (ewp->state == STATE_READY) {
+ retval = 0;
+ goto out_unlock;
+ }
+ if (signal_pending(current)) {
+ retval = -ERESTARTSYS;
+ break;
+ }
+ if (time == 0) {
+ retval = -ETIMEDOUT;
+ break;
+ }
+ }
+ list_del(&ewp->list);
+out_unlock:
+ spin_unlock(&info->lock);
+out:
+ return retval;
+}
+
+/*
+ * Returns waiting task that should be serviced first or NULL if none exists
+ */
+static struct ext_wait_queue *wq_get_first_waiter(
+ struct mqueue_inode_info *info, int sr)
+{
+ struct list_head *ptr;
+
+ ptr = info->e_wait_q[sr].list.prev;
+ if (ptr == &info->e_wait_q[sr].list)
+ return NULL;
+ return list_entry(ptr, struct ext_wait_queue, list);
+}
+
+/* Auxiliary functions to manipulate messages' list */
+static void msg_insert(struct msg_msg *ptr, struct mqueue_inode_info *info)
+{
+ int k;
+
+ k = info->attr.mq_curmsgs - 1;
+ while (k >= 0 && info->messages[k]->m_type >= ptr->m_type) {
+ info->messages[k + 1] = info->messages[k];
+ k--;
+ }
+ info->attr.mq_curmsgs++;
+ info->qsize += ptr->m_ts;
+ info->messages[k + 1] = ptr;
+}
+
+static inline struct msg_msg *msg_get(struct mqueue_inode_info *info)
+{
+ info->qsize -= info->messages[--info->attr.mq_curmsgs]->m_ts;
+ return info->messages[info->attr.mq_curmsgs];
+}
+
+static inline void set_cookie(struct sk_buff *skb, char code)
+{
+ ((char*)skb->data)[NOTIFY_COOKIE_LEN-1] = code;
+}
+
+/*
+ * The next function is only to split too long sys_mq_timedsend
+ */
+static void __do_notify(struct mqueue_inode_info *info)
+{
+ /* notification
+ * invoked when there is registered process and there isn't process
+ * waiting synchronously for message AND state of queue changed from
+ * empty to not empty. Here we are sure that no one is waiting
+ * synchronously. */
+ if (info->notify_owner &&
+ info->attr.mq_curmsgs == 1) {
+ struct siginfo sig_i;
+ switch (info->notify.sigev_notify) {
+ case SIGEV_NONE:
+ break;
+ case SIGEV_SIGNAL:
+ /* sends signal */
+
+ sig_i.si_signo = info->notify.sigev_signo;
+ sig_i.si_errno = 0;
+ sig_i.si_code = SI_MESGQ;
+ sig_i.si_value = info->notify.sigev_value;
+ /* map current pid/uid into info->owner's namespaces */
+ rcu_read_lock();
+ sig_i.si_pid = task_tgid_nr_ns(current,
+ ns_of_pid(info->notify_owner));
+ sig_i.si_uid = user_ns_map_uid(info->user->user_ns,
+ current_cred(), current_uid());
+ rcu_read_unlock();
+
+ kill_pid_info(info->notify.sigev_signo,
+ &sig_i, info->notify_owner);
+ break;
+ case SIGEV_THREAD:
+ set_cookie(info->notify_cookie, NOTIFY_WOKENUP);
+ netlink_sendskb(info->notify_sock, info->notify_cookie);
+ break;
+ }
+ /* after notification unregisters process */
+ put_pid(info->notify_owner);
+ info->notify_owner = NULL;
+ }
+ wake_up(&info->wait_q);
+}
+
+static int prepare_timeout(const struct timespec __user *u_abs_timeout,
+ ktime_t *expires, struct timespec *ts)
+{
+ if (copy_from_user(ts, u_abs_timeout, sizeof(struct timespec)))
+ return -EFAULT;
+ if (!timespec_valid(ts))
+ return -EINVAL;
+
+ *expires = timespec_to_ktime(*ts);
+ return 0;
+}
+
+static void remove_notification(struct mqueue_inode_info *info)
+{
+ if (info->notify_owner != NULL &&
+ info->notify.sigev_notify == SIGEV_THREAD) {
+ set_cookie(info->notify_cookie, NOTIFY_REMOVED);
+ netlink_sendskb(info->notify_sock, info->notify_cookie);
+ }
+ put_pid(info->notify_owner);
+ info->notify_owner = NULL;
+}
+
+static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr)
+{
+ if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0)
+ return 0;
+ if (capable(CAP_SYS_RESOURCE)) {
+ if (attr->mq_maxmsg > HARD_MSGMAX)
+ return 0;
+ } else {
+ if (attr->mq_maxmsg > ipc_ns->mq_msg_max ||
+ attr->mq_msgsize > ipc_ns->mq_msgsize_max)
+ return 0;
+ }
+ /* check for overflow */
+ if (attr->mq_msgsize > ULONG_MAX/attr->mq_maxmsg)
+ return 0;
+ if ((unsigned long)(attr->mq_maxmsg * (attr->mq_msgsize
+ + sizeof (struct msg_msg *))) <
+ (unsigned long)(attr->mq_maxmsg * attr->mq_msgsize))
+ return 0;
+ return 1;
+}
+
+/*
+ * Invoked when creating a new queue via sys_mq_open
+ */
+static struct file *do_create(struct ipc_namespace *ipc_ns, struct dentry *dir,
+ struct dentry *dentry, int oflag, umode_t mode,
+ struct mq_attr *attr)
+{
+ const struct cred *cred = current_cred();
+ struct file *result;
+ int ret;
+
+ if (attr) {
+ if (!mq_attr_ok(ipc_ns, attr)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ /* store for use during create */
+ dentry->d_fsdata = attr;
+ }
+
+ mode &= ~current_umask();
+ ret = mnt_want_write(ipc_ns->mq_mnt);
+ if (ret)
+ goto out;
+ ret = vfs_create(dir->d_inode, dentry, mode, NULL);
+ dentry->d_fsdata = NULL;
+ if (ret)
+ goto out_drop_write;
+
+ result = dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
+ /*
+ * dentry_open() took a persistent mnt_want_write(),
+ * so we can now drop this one.
+ */
+ mnt_drop_write(ipc_ns->mq_mnt);
+ return result;
+
+out_drop_write:
+ mnt_drop_write(ipc_ns->mq_mnt);
+out:
+ dput(dentry);
+ mntput(ipc_ns->mq_mnt);
+ return ERR_PTR(ret);
+}
+
+/* Opens existing queue */
+static struct file *do_open(struct ipc_namespace *ipc_ns,
+ struct dentry *dentry, int oflag)
+{
+ int ret;
+ const struct cred *cred = current_cred();
+
+ static const int oflag2acc[O_ACCMODE] = { MAY_READ, MAY_WRITE,
+ MAY_READ | MAY_WRITE };
+
+ if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ if (inode_permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE])) {
+ ret = -EACCES;
+ goto err;
+ }
+
+ return dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
+
+err:
+ dput(dentry);
+ mntput(ipc_ns->mq_mnt);
+ return ERR_PTR(ret);
+}
+
+SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
+ struct mq_attr __user *, u_attr)
+{
+ struct dentry *dentry;
+ struct file *filp;
+ char *name;
+ struct mq_attr attr;
+ int fd, error;
+ struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
+
+ if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr)))
+ return -EFAULT;
+
+ audit_mq_open(oflag, mode, u_attr ? &attr : NULL);
+
+ if (IS_ERR(name = getname(u_name)))
+ return PTR_ERR(name);
+
+ fd = get_unused_fd_flags(O_CLOEXEC);
+ if (fd < 0)
+ goto out_putname;
+
+ mutex_lock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
+ dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
+ if (IS_ERR(dentry)) {
+ error = PTR_ERR(dentry);
+ goto out_putfd;
+ }
+ mntget(ipc_ns->mq_mnt);
+
+ if (oflag & O_CREAT) {
+ if (dentry->d_inode) { /* entry already exists */
+ audit_inode(name, dentry);
+ if (oflag & O_EXCL) {
+ error = -EEXIST;
+ goto out;
+ }
+ filp = do_open(ipc_ns, dentry, oflag);
+ } else {
+ filp = do_create(ipc_ns, ipc_ns->mq_mnt->mnt_root,
+ dentry, oflag, mode,
+ u_attr ? &attr : NULL);
+ }
+ } else {
+ if (!dentry->d_inode) {
+ error = -ENOENT;
+ goto out;
+ }
+ audit_inode(name, dentry);
+ filp = do_open(ipc_ns, dentry, oflag);
+ }
+
+ if (IS_ERR(filp)) {
+ error = PTR_ERR(filp);
+ goto out_putfd;
+ }
+
+ fd_install(fd, filp);
+ goto out_upsem;
+
+out:
+ dput(dentry);
+ mntput(ipc_ns->mq_mnt);
+out_putfd:
+ put_unused_fd(fd);
+ fd = error;
+out_upsem:
+ mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
+out_putname:
+ putname(name);
+ return fd;
+}
+
+SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
+{
+ int err;
+ char *name;
+ struct dentry *dentry;
+ struct inode *inode = NULL;
+ struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
+
+ name = getname(u_name);
+ if (IS_ERR(name))
+ return PTR_ERR(name);
+
+ mutex_lock_nested(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex,
+ I_MUTEX_PARENT);
+ dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
+ goto out_unlock;
+ }
+
+ if (!dentry->d_inode) {
+ err = -ENOENT;
+ goto out_err;
+ }
+
+ inode = dentry->d_inode;
+ if (inode)
+ ihold(inode);
+ err = mnt_want_write(ipc_ns->mq_mnt);
+ if (err)
+ goto out_err;
+ err = vfs_unlink(dentry->d_parent->d_inode, dentry);
+ mnt_drop_write(ipc_ns->mq_mnt);
+out_err:
+ dput(dentry);
+
+out_unlock:
+ mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
+ putname(name);
+ if (inode)
+ iput(inode);
+
+ return err;
+}
+
+/* Pipelined send and receive functions.
+ *
+ * If a receiver finds no waiting message, then it registers itself in the
+ * list of waiting receivers. A sender checks that list before adding the new
+ * message into the message array. If there is a waiting receiver, then it
+ * bypasses the message array and directly hands the message over to the
+ * receiver.
+ * The receiver accepts the message and returns without grabbing the queue
+ * spinlock. Therefore an intermediate STATE_PENDING state and memory barriers
+ * are necessary. The same algorithm is used for sysv semaphores, see
+ * ipc/sem.c for more details.
+ *
+ * The same algorithm is used for senders.
+ */
+
+/* pipelined_send() - send a message directly to the task waiting in
+ * sys_mq_timedreceive() (without inserting message into a queue).
+ */
+static inline void pipelined_send(struct mqueue_inode_info *info,
+ struct msg_msg *message,
+ struct ext_wait_queue *receiver)
+{
+ receiver->msg = message;
+ list_del(&receiver->list);
+ receiver->state = STATE_PENDING;
+ wake_up_process(receiver->task);
+ smp_wmb();
+ receiver->state = STATE_READY;
+}
+
+/* pipelined_receive() - if there is task waiting in sys_mq_timedsend()
+ * gets its message and put to the queue (we have one free place for sure). */
+static inline void pipelined_receive(struct mqueue_inode_info *info)
+{
+ struct ext_wait_queue *sender = wq_get_first_waiter(info, SEND);
+
+ if (!sender) {
+ /* for poll */
+ wake_up_interruptible(&info->wait_q);
+ return;
+ }
+ msg_insert(sender->msg, info);
+ list_del(&sender->list);
+ sender->state = STATE_PENDING;
+ wake_up_process(sender->task);
+ smp_wmb();
+ sender->state = STATE_READY;
+}
+
+SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr,
+ size_t, msg_len, unsigned int, msg_prio,
+ const struct timespec __user *, u_abs_timeout)
+{
+ struct file *filp;
+ struct inode *inode;
+ struct ext_wait_queue wait;
+ struct ext_wait_queue *receiver;
+ struct msg_msg *msg_ptr;
+ struct mqueue_inode_info *info;
+ ktime_t expires, *timeout = NULL;
+ struct timespec ts;
+ int ret;
+
+ if (u_abs_timeout) {
+ int res = prepare_timeout(u_abs_timeout, &expires, &ts);
+ if (res)
+ return res;
+ timeout = &expires;
+ }
+
+ if (unlikely(msg_prio >= (unsigned long) MQ_PRIO_MAX))
+ return -EINVAL;
+
+ audit_mq_sendrecv(mqdes, msg_len, msg_prio, timeout ? &ts : NULL);
+
+ filp = fget(mqdes);
+ if (unlikely(!filp)) {
+ ret = -EBADF;
+ goto out;
+ }
+
+ inode = filp->f_path.dentry->d_inode;
+ if (unlikely(filp->f_op != &mqueue_file_operations)) {
+ ret = -EBADF;
+ goto out_fput;
+ }
+ info = MQUEUE_I(inode);
+ audit_inode(NULL, filp->f_path.dentry);
+
+ if (unlikely(!(filp->f_mode & FMODE_WRITE))) {
+ ret = -EBADF;
+ goto out_fput;
+ }
+
+ if (unlikely(msg_len > info->attr.mq_msgsize)) {
+ ret = -EMSGSIZE;
+ goto out_fput;
+ }
+
+ /* First try to allocate memory, before doing anything with
+ * existing queues. */
+ msg_ptr = load_msg(u_msg_ptr, msg_len);
+ if (IS_ERR(msg_ptr)) {
+ ret = PTR_ERR(msg_ptr);
+ goto out_fput;
+ }
+ msg_ptr->m_ts = msg_len;
+ msg_ptr->m_type = msg_prio;
+
+ spin_lock(&info->lock);
+
+ if (info->attr.mq_curmsgs == info->attr.mq_maxmsg) {
+ if (filp->f_flags & O_NONBLOCK) {
+ spin_unlock(&info->lock);
+ ret = -EAGAIN;
+ } else {
+ wait.task = current;
+ wait.msg = (void *) msg_ptr;
+ wait.state = STATE_NONE;
+ ret = wq_sleep(info, SEND, timeout, &wait);
+ }
+ if (ret < 0)
+ free_msg(msg_ptr);
+ } else {
+ receiver = wq_get_first_waiter(info, RECV);
+ if (receiver) {
+ pipelined_send(info, msg_ptr, receiver);
+ } else {
+ /* adds message to the queue */
+ msg_insert(msg_ptr, info);
+ __do_notify(info);
+ }
+ inode->i_atime = inode->i_mtime = inode->i_ctime =
+ CURRENT_TIME;
+ spin_unlock(&info->lock);
+ ret = 0;
+ }
+out_fput:
+ fput(filp);
+out:
+ return ret;
+}
+
+SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr,
+ size_t, msg_len, unsigned int __user *, u_msg_prio,
+ const struct timespec __user *, u_abs_timeout)
+{
+ ssize_t ret;
+ struct msg_msg *msg_ptr;
+ struct file *filp;
+ struct inode *inode;
+ struct mqueue_inode_info *info;
+ struct ext_wait_queue wait;
+ ktime_t expires, *timeout = NULL;
+ struct timespec ts;
+
+ if (u_abs_timeout) {
+ int res = prepare_timeout(u_abs_timeout, &expires, &ts);
+ if (res)
+ return res;
+ timeout = &expires;
+ }
+
+ audit_mq_sendrecv(mqdes, msg_len, 0, timeout ? &ts : NULL);
+
+ filp = fget(mqdes);
+ if (unlikely(!filp)) {
+ ret = -EBADF;
+ goto out;
+ }
+
+ inode = filp->f_path.dentry->d_inode;
+ if (unlikely(filp->f_op != &mqueue_file_operations)) {
+ ret = -EBADF;
+ goto out_fput;
+ }
+ info = MQUEUE_I(inode);
+ audit_inode(NULL, filp->f_path.dentry);
+
+ if (unlikely(!(filp->f_mode & FMODE_READ))) {
+ ret = -EBADF;
+ goto out_fput;
+ }
+
+ /* checks if buffer is big enough */
+ if (unlikely(msg_len < info->attr.mq_msgsize)) {
+ ret = -EMSGSIZE;
+ goto out_fput;
+ }
+
+ spin_lock(&info->lock);
+ if (info->attr.mq_curmsgs == 0) {
+ if (filp->f_flags & O_NONBLOCK) {
+ spin_unlock(&info->lock);
+ ret = -EAGAIN;
+ } else {
+ wait.task = current;
+ wait.state = STATE_NONE;
+ ret = wq_sleep(info, RECV, timeout, &wait);
+ msg_ptr = wait.msg;
+ }
+ } else {
+ msg_ptr = msg_get(info);
+
+ inode->i_atime = inode->i_mtime = inode->i_ctime =
+ CURRENT_TIME;
+
+ /* There is now free space in queue. */
+ pipelined_receive(info);
+ spin_unlock(&info->lock);
+ ret = 0;
+ }
+ if (ret == 0) {
+ ret = msg_ptr->m_ts;
+
+ if ((u_msg_prio && put_user(msg_ptr->m_type, u_msg_prio)) ||
+ store_msg(u_msg_ptr, msg_ptr, msg_ptr->m_ts)) {
+ ret = -EFAULT;
+ }
+ free_msg(msg_ptr);
+ }
+out_fput:
+ fput(filp);
+out:
+ return ret;
+}
+
+/*
+ * Notes: the case when user wants us to deregister (with NULL as pointer)
+ * and he isn't currently owner of notification, will be silently discarded.
+ * It isn't explicitly defined in the POSIX.
+ */
+SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes,
+ const struct sigevent __user *, u_notification)
+{
+ int ret;
+ struct file *filp;
+ struct sock *sock;
+ struct inode *inode;
+ struct sigevent notification;
+ struct mqueue_inode_info *info;
+ struct sk_buff *nc;
+
+ if (u_notification) {
+ if (copy_from_user(&notification, u_notification,
+ sizeof(struct sigevent)))
+ return -EFAULT;
+ }
+
+ audit_mq_notify(mqdes, u_notification ? &notification : NULL);
+
+ nc = NULL;
+ sock = NULL;
+ if (u_notification != NULL) {
+ if (unlikely(notification.sigev_notify != SIGEV_NONE &&
+ notification.sigev_notify != SIGEV_SIGNAL &&
+ notification.sigev_notify != SIGEV_THREAD))
+ return -EINVAL;
+ if (notification.sigev_notify == SIGEV_SIGNAL &&
+ !valid_signal(notification.sigev_signo)) {
+ return -EINVAL;
+ }
+ if (notification.sigev_notify == SIGEV_THREAD) {
+ long timeo;
+
+ /* create the notify skb */
+ nc = alloc_skb(NOTIFY_COOKIE_LEN, GFP_KERNEL);
+ if (!nc) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ if (copy_from_user(nc->data,
+ notification.sigev_value.sival_ptr,
+ NOTIFY_COOKIE_LEN)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ /* TODO: add a header? */
+ skb_put(nc, NOTIFY_COOKIE_LEN);
+ /* and attach it to the socket */
+retry:
+ filp = fget(notification.sigev_signo);
+ if (!filp) {
+ ret = -EBADF;
+ goto out;
+ }
+ sock = netlink_getsockbyfilp(filp);
+ fput(filp);
+ if (IS_ERR(sock)) {
+ ret = PTR_ERR(sock);
+ sock = NULL;
+ goto out;
+ }
+
+ timeo = MAX_SCHEDULE_TIMEOUT;
+ ret = netlink_attachskb(sock, nc, &timeo, NULL);
+ if (ret == 1)
+ goto retry;
+ if (ret) {
+ sock = NULL;
+ nc = NULL;
+ goto out;
+ }
+ }
+ }
+
+ filp = fget(mqdes);
+ if (!filp) {
+ ret = -EBADF;
+ goto out;
+ }
+
+ inode = filp->f_path.dentry->d_inode;
+ if (unlikely(filp->f_op != &mqueue_file_operations)) {
+ ret = -EBADF;
+ goto out_fput;
+ }
+ info = MQUEUE_I(inode);
+
+ ret = 0;
+ spin_lock(&info->lock);
+ if (u_notification == NULL) {
+ if (info->notify_owner == task_tgid(current)) {
+ remove_notification(info);
+ inode->i_atime = inode->i_ctime = CURRENT_TIME;
+ }
+ } else if (info->notify_owner != NULL) {
+ ret = -EBUSY;
+ } else {
+ switch (notification.sigev_notify) {
+ case SIGEV_NONE:
+ info->notify.sigev_notify = SIGEV_NONE;
+ break;
+ case SIGEV_THREAD:
+ info->notify_sock = sock;
+ info->notify_cookie = nc;
+ sock = NULL;
+ nc = NULL;
+ info->notify.sigev_notify = SIGEV_THREAD;
+ break;
+ case SIGEV_SIGNAL:
+ info->notify.sigev_signo = notification.sigev_signo;
+ info->notify.sigev_value = notification.sigev_value;
+ info->notify.sigev_notify = SIGEV_SIGNAL;
+ break;
+ }
+
+ info->notify_owner = get_pid(task_tgid(current));
+ inode->i_atime = inode->i_ctime = CURRENT_TIME;
+ }
+ spin_unlock(&info->lock);
+out_fput:
+ fput(filp);
+out:
+ if (sock) {
+ netlink_detachskb(sock, nc);
+ } else if (nc) {
+ dev_kfree_skb(nc);
+ }
+ return ret;
+}
+
+SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes,
+ const struct mq_attr __user *, u_mqstat,
+ struct mq_attr __user *, u_omqstat)
+{
+ int ret;
+ struct mq_attr mqstat, omqstat;
+ struct file *filp;
+ struct inode *inode;
+ struct mqueue_inode_info *info;
+
+ if (u_mqstat != NULL) {
+ if (copy_from_user(&mqstat, u_mqstat, sizeof(struct mq_attr)))
+ return -EFAULT;
+ if (mqstat.mq_flags & (~O_NONBLOCK))
+ return -EINVAL;
+ }
+
+ filp = fget(mqdes);
+ if (!filp) {
+ ret = -EBADF;
+ goto out;
+ }
+
+ inode = filp->f_path.dentry->d_inode;
+ if (unlikely(filp->f_op != &mqueue_file_operations)) {
+ ret = -EBADF;
+ goto out_fput;
+ }
+ info = MQUEUE_I(inode);
+
+ spin_lock(&info->lock);
+
+ omqstat = info->attr;
+ omqstat.mq_flags = filp->f_flags & O_NONBLOCK;
+ if (u_mqstat) {
+ audit_mq_getsetattr(mqdes, &mqstat);
+ spin_lock(&filp->f_lock);
+ if (mqstat.mq_flags & O_NONBLOCK)
+ filp->f_flags |= O_NONBLOCK;
+ else
+ filp->f_flags &= ~O_NONBLOCK;
+ spin_unlock(&filp->f_lock);
+
+ inode->i_atime = inode->i_ctime = CURRENT_TIME;
+ }
+
+ spin_unlock(&info->lock);
+
+ ret = 0;
+ if (u_omqstat != NULL && copy_to_user(u_omqstat, &omqstat,
+ sizeof(struct mq_attr)))
+ ret = -EFAULT;
+
+out_fput:
+ fput(filp);
+out:
+ return ret;
+}
+
+static const struct inode_operations mqueue_dir_inode_operations = {
+ .lookup = simple_lookup,
+ .create = mqueue_create,
+ .unlink = mqueue_unlink,
+};
+
+static const struct file_operations mqueue_file_operations = {
+ .flush = mqueue_flush_file,
+ .poll = mqueue_poll_file,
+ .read = mqueue_read_file,
+ .llseek = default_llseek,
+};
+
+static const struct super_operations mqueue_super_ops = {
+ .alloc_inode = mqueue_alloc_inode,
+ .destroy_inode = mqueue_destroy_inode,
+ .evict_inode = mqueue_evict_inode,
+ .statfs = simple_statfs,
+};
+
+static struct file_system_type mqueue_fs_type = {
+ .name = "mqueue",
+ .mount = mqueue_mount,
+ .kill_sb = kill_litter_super,
+};
+
+int mq_init_ns(struct ipc_namespace *ns)
+{
+ ns->mq_queues_count = 0;
+ ns->mq_queues_max = DFLT_QUEUESMAX;
+ ns->mq_msg_max = DFLT_MSGMAX;
+ ns->mq_msgsize_max = DFLT_MSGSIZEMAX;
+
+ ns->mq_mnt = kern_mount_data(&mqueue_fs_type, ns);
+ if (IS_ERR(ns->mq_mnt)) {
+ int err = PTR_ERR(ns->mq_mnt);
+ ns->mq_mnt = NULL;
+ return err;
+ }
+ return 0;
+}
+
+void mq_clear_sbinfo(struct ipc_namespace *ns)
+{
+ ns->mq_mnt->mnt_sb->s_fs_info = NULL;
+}
+
+void mq_put_mnt(struct ipc_namespace *ns)
+{
+ kern_unmount(ns->mq_mnt);
+}
+
+static int __init init_mqueue_fs(void)
+{
+ int error;
+
+ mqueue_inode_cachep = kmem_cache_create("mqueue_inode_cache",
+ sizeof(struct mqueue_inode_info), 0,
+ SLAB_HWCACHE_ALIGN, init_once);
+ if (mqueue_inode_cachep == NULL)
+ return -ENOMEM;
+
+ /* ignore failures - they are not fatal */
+ mq_sysctl_table = mq_register_sysctl_table();
+
+ error = register_filesystem(&mqueue_fs_type);
+ if (error)
+ goto out_sysctl;
+
+ spin_lock_init(&mq_lock);
+
+ error = mq_init_ns(&init_ipc_ns);
+ if (error)
+ goto out_filesystem;
+
+ return 0;
+
+out_filesystem:
+ unregister_filesystem(&mqueue_fs_type);
+out_sysctl:
+ if (mq_sysctl_table)
+ unregister_sysctl_table(mq_sysctl_table);
+ kmem_cache_destroy(mqueue_inode_cachep);
+ return error;
+}
+
+__initcall(init_mqueue_fs);
diff --git a/ipc/msg.c b/ipc/msg.c
new file mode 100644
index 00000000..7385de25
--- /dev/null
+++ b/ipc/msg.c
@@ -0,0 +1,944 @@
+/*
+ * linux/ipc/msg.c
+ * Copyright (C) 1992 Krishna Balasubramanian
+ *
+ * Removed all the remaining kerneld mess
+ * Catch the -EFAULT stuff properly
+ * Use GFP_KERNEL for messages as in 1.2
+ * Fixed up the unchecked user space derefs
+ * Copyright (C) 1998 Alan Cox & Andi Kleen
+ *
+ * /proc/sysvipc/msg support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
+ *
+ * mostly rewritten, threaded and wake-one semantics added
+ * MSGMAX limit removed, sysctl's added
+ * (c) 1999 Manfred Spraul <manfred@colorfullife.com>
+ *
+ * support for audit of ipc object properties and permission changes
+ * Dustin Kirkland <dustin.kirkland@us.ibm.com>
+ *
+ * namespaces support
+ * OpenVZ, SWsoft Inc.
+ * Pavel Emelianov <xemul@openvz.org>
+ */
+
+#include <linux/capability.h>
+#include <linux/msg.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/list.h>
+#include <linux/security.h>
+#include <linux/sched.h>
+#include <linux/syscalls.h>
+#include <linux/audit.h>
+#include <linux/seq_file.h>
+#include <linux/rwsem.h>
+#include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
+
+#include <asm/current.h>
+#include <asm/uaccess.h>
+#include "util.h"
+
+/*
+ * one msg_receiver structure for each sleeping receiver:
+ */
+struct msg_receiver {
+ struct list_head r_list;
+ struct task_struct *r_tsk;
+
+ int r_mode;
+ long r_msgtype;
+ long r_maxsize;
+
+ struct msg_msg *volatile r_msg;
+};
+
+/* one msg_sender for each sleeping sender */
+struct msg_sender {
+ struct list_head list;
+ struct task_struct *tsk;
+};
+
+#define SEARCH_ANY 1
+#define SEARCH_EQUAL 2
+#define SEARCH_NOTEQUAL 3
+#define SEARCH_LESSEQUAL 4
+
+#define msg_ids(ns) ((ns)->ids[IPC_MSG_IDS])
+
+#define msg_unlock(msq) ipc_unlock(&(msq)->q_perm)
+
+static void freeque(struct ipc_namespace *, struct kern_ipc_perm *);
+static int newque(struct ipc_namespace *, struct ipc_params *);
+#ifdef CONFIG_PROC_FS
+static int sysvipc_msg_proc_show(struct seq_file *s, void *it);
+#endif
+
+/*
+ * Scale msgmni with the available lowmem size: the memory dedicated to msg
+ * queues should occupy at most 1/MSG_MEM_SCALE of lowmem.
+ * Also take into account the number of nsproxies created so far.
+ * This should be done staying within the (MSGMNI , IPCMNI/nr_ipc_ns) range.
+ */
+void recompute_msgmni(struct ipc_namespace *ns)
+{
+ struct sysinfo i;
+ unsigned long allowed;
+ int nb_ns;
+
+ si_meminfo(&i);
+ allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit)
+ / MSGMNB;
+ nb_ns = atomic_read(&nr_ipc_ns);
+ allowed /= nb_ns;
+
+ if (allowed < MSGMNI) {
+ ns->msg_ctlmni = MSGMNI;
+ return;
+ }
+
+ if (allowed > IPCMNI / nb_ns) {
+ ns->msg_ctlmni = IPCMNI / nb_ns;
+ return;
+ }
+
+ ns->msg_ctlmni = allowed;
+}
+
+void msg_init_ns(struct ipc_namespace *ns)
+{
+ ns->msg_ctlmax = MSGMAX;
+ ns->msg_ctlmnb = MSGMNB;
+
+ recompute_msgmni(ns);
+
+ atomic_set(&ns->msg_bytes, 0);
+ atomic_set(&ns->msg_hdrs, 0);
+ ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
+}
+
+#ifdef CONFIG_IPC_NS
+void msg_exit_ns(struct ipc_namespace *ns)
+{
+ free_ipcs(ns, &msg_ids(ns), freeque);
+ idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
+}
+#endif
+
+void __init msg_init(void)
+{
+ msg_init_ns(&init_ipc_ns);
+
+ printk(KERN_INFO "msgmni has been set to %d\n",
+ init_ipc_ns.msg_ctlmni);
+
+ ipc_init_proc_interface("sysvipc/msg",
+ " key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n",
+ IPC_MSG_IDS, sysvipc_msg_proc_show);
+}
+
+/*
+ * msg_lock_(check_) routines are called in the paths where the rw_mutex
+ * is not held.
+ */
+static inline struct msg_queue *msg_lock(struct ipc_namespace *ns, int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_lock(&msg_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct msg_queue *)ipcp;
+
+ return container_of(ipcp, struct msg_queue, q_perm);
+}
+
+static inline struct msg_queue *msg_lock_check(struct ipc_namespace *ns,
+ int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_lock_check(&msg_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct msg_queue *)ipcp;
+
+ return container_of(ipcp, struct msg_queue, q_perm);
+}
+
+static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
+{
+ ipc_rmid(&msg_ids(ns), &s->q_perm);
+}
+
+/**
+ * newque - Create a new msg queue
+ * @ns: namespace
+ * @params: ptr to the structure that contains the key and msgflg
+ *
+ * Called with msg_ids.rw_mutex held (writer)
+ */
+static int newque(struct ipc_namespace *ns, struct ipc_params *params)
+{
+ struct msg_queue *msq;
+ int id, retval;
+ key_t key = params->key;
+ int msgflg = params->flg;
+
+ msq = ipc_rcu_alloc(sizeof(*msq));
+ if (!msq)
+ return -ENOMEM;
+
+ msq->q_perm.mode = msgflg & S_IRWXUGO;
+ msq->q_perm.key = key;
+
+ msq->q_perm.security = NULL;
+ retval = security_msg_queue_alloc(msq);
+ if (retval) {
+ ipc_rcu_putref(msq);
+ return retval;
+ }
+
+ /*
+ * ipc_addid() locks msq
+ */
+ id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
+ if (id < 0) {
+ security_msg_queue_free(msq);
+ ipc_rcu_putref(msq);
+ return id;
+ }
+
+ msq->q_stime = msq->q_rtime = 0;
+ msq->q_ctime = get_seconds();
+ msq->q_cbytes = msq->q_qnum = 0;
+ msq->q_qbytes = ns->msg_ctlmnb;
+ msq->q_lspid = msq->q_lrpid = 0;
+ INIT_LIST_HEAD(&msq->q_messages);
+ INIT_LIST_HEAD(&msq->q_receivers);
+ INIT_LIST_HEAD(&msq->q_senders);
+
+ msg_unlock(msq);
+
+ return msq->q_perm.id;
+}
+
+static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss)
+{
+ mss->tsk = current;
+ current->state = TASK_INTERRUPTIBLE;
+ list_add_tail(&mss->list, &msq->q_senders);
+}
+
+static inline void ss_del(struct msg_sender *mss)
+{
+ if (mss->list.next != NULL)
+ list_del(&mss->list);
+}
+
+static void ss_wakeup(struct list_head *h, int kill)
+{
+ struct list_head *tmp;
+
+ tmp = h->next;
+ while (tmp != h) {
+ struct msg_sender *mss;
+
+ mss = list_entry(tmp, struct msg_sender, list);
+ tmp = tmp->next;
+ if (kill)
+ mss->list.next = NULL;
+ wake_up_process(mss->tsk);
+ }
+}
+
+static void expunge_all(struct msg_queue *msq, int res)
+{
+ struct list_head *tmp;
+
+ tmp = msq->q_receivers.next;
+ while (tmp != &msq->q_receivers) {
+ struct msg_receiver *msr;
+
+ msr = list_entry(tmp, struct msg_receiver, r_list);
+ tmp = tmp->next;
+ msr->r_msg = NULL;
+ wake_up_process(msr->r_tsk);
+ smp_mb();
+ msr->r_msg = ERR_PTR(res);
+ }
+}
+
+/*
+ * freeque() wakes up waiters on the sender and receiver waiting queue,
+ * removes the message queue from message queue ID IDR, and cleans up all the
+ * messages associated with this queue.
+ *
+ * msg_ids.rw_mutex (writer) and the spinlock for this message queue are held
+ * before freeque() is called. msg_ids.rw_mutex remains locked on exit.
+ */
+static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
+{
+ struct list_head *tmp;
+ struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
+
+ expunge_all(msq, -EIDRM);
+ ss_wakeup(&msq->q_senders, 1);
+ msg_rmid(ns, msq);
+ msg_unlock(msq);
+
+ tmp = msq->q_messages.next;
+ while (tmp != &msq->q_messages) {
+ struct msg_msg *msg = list_entry(tmp, struct msg_msg, m_list);
+
+ tmp = tmp->next;
+ atomic_dec(&ns->msg_hdrs);
+ free_msg(msg);
+ }
+ atomic_sub(msq->q_cbytes, &ns->msg_bytes);
+ security_msg_queue_free(msq);
+ ipc_rcu_putref(msq);
+}
+
+/*
+ * Called with msg_ids.rw_mutex and ipcp locked.
+ */
+static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg)
+{
+ struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
+
+ return security_msg_queue_associate(msq, msgflg);
+}
+
+SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg)
+{
+ struct ipc_namespace *ns;
+ struct ipc_ops msg_ops;
+ struct ipc_params msg_params;
+
+ ns = current->nsproxy->ipc_ns;
+
+ msg_ops.getnew = newque;
+ msg_ops.associate = msg_security;
+ msg_ops.more_checks = NULL;
+
+ msg_params.key = key;
+ msg_params.flg = msgflg;
+
+ return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params);
+}
+
+static inline unsigned long
+copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version)
+{
+ switch(version) {
+ case IPC_64:
+ return copy_to_user(buf, in, sizeof(*in));
+ case IPC_OLD:
+ {
+ struct msqid_ds out;
+
+ memset(&out, 0, sizeof(out));
+
+ ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm);
+
+ out.msg_stime = in->msg_stime;
+ out.msg_rtime = in->msg_rtime;
+ out.msg_ctime = in->msg_ctime;
+
+ if (in->msg_cbytes > USHRT_MAX)
+ out.msg_cbytes = USHRT_MAX;
+ else
+ out.msg_cbytes = in->msg_cbytes;
+ out.msg_lcbytes = in->msg_cbytes;
+
+ if (in->msg_qnum > USHRT_MAX)
+ out.msg_qnum = USHRT_MAX;
+ else
+ out.msg_qnum = in->msg_qnum;
+
+ if (in->msg_qbytes > USHRT_MAX)
+ out.msg_qbytes = USHRT_MAX;
+ else
+ out.msg_qbytes = in->msg_qbytes;
+ out.msg_lqbytes = in->msg_qbytes;
+
+ out.msg_lspid = in->msg_lspid;
+ out.msg_lrpid = in->msg_lrpid;
+
+ return copy_to_user(buf, &out, sizeof(out));
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static inline unsigned long
+copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version)
+{
+ switch(version) {
+ case IPC_64:
+ if (copy_from_user(out, buf, sizeof(*out)))
+ return -EFAULT;
+ return 0;
+ case IPC_OLD:
+ {
+ struct msqid_ds tbuf_old;
+
+ if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
+ return -EFAULT;
+
+ out->msg_perm.uid = tbuf_old.msg_perm.uid;
+ out->msg_perm.gid = tbuf_old.msg_perm.gid;
+ out->msg_perm.mode = tbuf_old.msg_perm.mode;
+
+ if (tbuf_old.msg_qbytes == 0)
+ out->msg_qbytes = tbuf_old.msg_lqbytes;
+ else
+ out->msg_qbytes = tbuf_old.msg_qbytes;
+
+ return 0;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+/*
+ * This function handles some msgctl commands which require the rw_mutex
+ * to be held in write mode.
+ * NOTE: no locks must be held, the rw_mutex is taken inside this function.
+ */
+static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
+ struct msqid_ds __user *buf, int version)
+{
+ struct kern_ipc_perm *ipcp;
+ struct msqid64_ds uninitialized_var(msqid64);
+ struct msg_queue *msq;
+ int err;
+
+ if (cmd == IPC_SET) {
+ if (copy_msqid_from_user(&msqid64, buf, version))
+ return -EFAULT;
+ }
+
+ ipcp = ipcctl_pre_down(ns, &msg_ids(ns), msqid, cmd,
+ &msqid64.msg_perm, msqid64.msg_qbytes);
+ if (IS_ERR(ipcp))
+ return PTR_ERR(ipcp);
+
+ msq = container_of(ipcp, struct msg_queue, q_perm);
+
+ err = security_msg_queue_msgctl(msq, cmd);
+ if (err)
+ goto out_unlock;
+
+ switch (cmd) {
+ case IPC_RMID:
+ freeque(ns, ipcp);
+ goto out_up;
+ case IPC_SET:
+ if (msqid64.msg_qbytes > ns->msg_ctlmnb &&
+ !capable(CAP_SYS_RESOURCE)) {
+ err = -EPERM;
+ goto out_unlock;
+ }
+
+ msq->q_qbytes = msqid64.msg_qbytes;
+
+ ipc_update_perm(&msqid64.msg_perm, ipcp);
+ msq->q_ctime = get_seconds();
+ /* sleeping receivers might be excluded by
+ * stricter permissions.
+ */
+ expunge_all(msq, -EAGAIN);
+ /* sleeping senders might be able to send
+ * due to a larger queue size.
+ */
+ ss_wakeup(&msq->q_senders, 0);
+ break;
+ default:
+ err = -EINVAL;
+ }
+out_unlock:
+ msg_unlock(msq);
+out_up:
+ up_write(&msg_ids(ns).rw_mutex);
+ return err;
+}
+
+SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
+{
+ struct msg_queue *msq;
+ int err, version;
+ struct ipc_namespace *ns;
+
+ if (msqid < 0 || cmd < 0)
+ return -EINVAL;
+
+ version = ipc_parse_version(&cmd);
+ ns = current->nsproxy->ipc_ns;
+
+ switch (cmd) {
+ case IPC_INFO:
+ case MSG_INFO:
+ {
+ struct msginfo msginfo;
+ int max_id;
+
+ if (!buf)
+ return -EFAULT;
+ /*
+ * We must not return kernel stack data.
+ * due to padding, it's not enough
+ * to set all member fields.
+ */
+ err = security_msg_queue_msgctl(NULL, cmd);
+ if (err)
+ return err;
+
+ memset(&msginfo, 0, sizeof(msginfo));
+ msginfo.msgmni = ns->msg_ctlmni;
+ msginfo.msgmax = ns->msg_ctlmax;
+ msginfo.msgmnb = ns->msg_ctlmnb;
+ msginfo.msgssz = MSGSSZ;
+ msginfo.msgseg = MSGSEG;
+ down_read(&msg_ids(ns).rw_mutex);
+ if (cmd == MSG_INFO) {
+ msginfo.msgpool = msg_ids(ns).in_use;
+ msginfo.msgmap = atomic_read(&ns->msg_hdrs);
+ msginfo.msgtql = atomic_read(&ns->msg_bytes);
+ } else {
+ msginfo.msgmap = MSGMAP;
+ msginfo.msgpool = MSGPOOL;
+ msginfo.msgtql = MSGTQL;
+ }
+ max_id = ipc_get_maxid(&msg_ids(ns));
+ up_read(&msg_ids(ns).rw_mutex);
+ if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
+ return -EFAULT;
+ return (max_id < 0) ? 0 : max_id;
+ }
+ case MSG_STAT: /* msqid is an index rather than a msg queue id */
+ case IPC_STAT:
+ {
+ struct msqid64_ds tbuf;
+ int success_return;
+
+ if (!buf)
+ return -EFAULT;
+
+ if (cmd == MSG_STAT) {
+ msq = msg_lock(ns, msqid);
+ if (IS_ERR(msq))
+ return PTR_ERR(msq);
+ success_return = msq->q_perm.id;
+ } else {
+ msq = msg_lock_check(ns, msqid);
+ if (IS_ERR(msq))
+ return PTR_ERR(msq);
+ success_return = 0;
+ }
+ err = -EACCES;
+ if (ipcperms(ns, &msq->q_perm, S_IRUGO))
+ goto out_unlock;
+
+ err = security_msg_queue_msgctl(msq, cmd);
+ if (err)
+ goto out_unlock;
+
+ memset(&tbuf, 0, sizeof(tbuf));
+
+ kernel_to_ipc64_perm(&msq->q_perm, &tbuf.msg_perm);
+ tbuf.msg_stime = msq->q_stime;
+ tbuf.msg_rtime = msq->q_rtime;
+ tbuf.msg_ctime = msq->q_ctime;
+ tbuf.msg_cbytes = msq->q_cbytes;
+ tbuf.msg_qnum = msq->q_qnum;
+ tbuf.msg_qbytes = msq->q_qbytes;
+ tbuf.msg_lspid = msq->q_lspid;
+ tbuf.msg_lrpid = msq->q_lrpid;
+ msg_unlock(msq);
+ if (copy_msqid_to_user(buf, &tbuf, version))
+ return -EFAULT;
+ return success_return;
+ }
+ case IPC_SET:
+ case IPC_RMID:
+ err = msgctl_down(ns, msqid, cmd, buf, version);
+ return err;
+ default:
+ return -EINVAL;
+ }
+
+out_unlock:
+ msg_unlock(msq);
+ return err;
+}
+
+static int testmsg(struct msg_msg *msg, long type, int mode)
+{
+ switch(mode)
+ {
+ case SEARCH_ANY:
+ return 1;
+ case SEARCH_LESSEQUAL:
+ if (msg->m_type <=type)
+ return 1;
+ break;
+ case SEARCH_EQUAL:
+ if (msg->m_type == type)
+ return 1;
+ break;
+ case SEARCH_NOTEQUAL:
+ if (msg->m_type != type)
+ return 1;
+ break;
+ }
+ return 0;
+}
+
+static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg)
+{
+ struct list_head *tmp;
+
+ tmp = msq->q_receivers.next;
+ while (tmp != &msq->q_receivers) {
+ struct msg_receiver *msr;
+
+ msr = list_entry(tmp, struct msg_receiver, r_list);
+ tmp = tmp->next;
+ if (testmsg(msg, msr->r_msgtype, msr->r_mode) &&
+ !security_msg_queue_msgrcv(msq, msg, msr->r_tsk,
+ msr->r_msgtype, msr->r_mode)) {
+
+ list_del(&msr->r_list);
+ if (msr->r_maxsize < msg->m_ts) {
+ msr->r_msg = NULL;
+ wake_up_process(msr->r_tsk);
+ smp_mb();
+ msr->r_msg = ERR_PTR(-E2BIG);
+ } else {
+ msr->r_msg = NULL;
+ msq->q_lrpid = task_pid_vnr(msr->r_tsk);
+ msq->q_rtime = get_seconds();
+ wake_up_process(msr->r_tsk);
+ smp_mb();
+ msr->r_msg = msg;
+
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+
+long do_msgsnd(int msqid, long mtype, void __user *mtext,
+ size_t msgsz, int msgflg)
+{
+ struct msg_queue *msq;
+ struct msg_msg *msg;
+ int err;
+ struct ipc_namespace *ns;
+
+ ns = current->nsproxy->ipc_ns;
+
+ if (msgsz > ns->msg_ctlmax || (long) msgsz < 0 || msqid < 0)
+ return -EINVAL;
+ if (mtype < 1)
+ return -EINVAL;
+
+ msg = load_msg(mtext, msgsz);
+ if (IS_ERR(msg))
+ return PTR_ERR(msg);
+
+ msg->m_type = mtype;
+ msg->m_ts = msgsz;
+
+ msq = msg_lock_check(ns, msqid);
+ if (IS_ERR(msq)) {
+ err = PTR_ERR(msq);
+ goto out_free;
+ }
+
+ for (;;) {
+ struct msg_sender s;
+
+ err = -EACCES;
+ if (ipcperms(ns, &msq->q_perm, S_IWUGO))
+ goto out_unlock_free;
+
+ err = security_msg_queue_msgsnd(msq, msg, msgflg);
+ if (err)
+ goto out_unlock_free;
+
+ if (msgsz + msq->q_cbytes <= msq->q_qbytes &&
+ 1 + msq->q_qnum <= msq->q_qbytes) {
+ break;
+ }
+
+ /* queue full, wait: */
+ if (msgflg & IPC_NOWAIT) {
+ err = -EAGAIN;
+ goto out_unlock_free;
+ }
+ ss_add(msq, &s);
+ ipc_rcu_getref(msq);
+ msg_unlock(msq);
+ schedule();
+
+ ipc_lock_by_ptr(&msq->q_perm);
+ ipc_rcu_putref(msq);
+ if (msq->q_perm.deleted) {
+ err = -EIDRM;
+ goto out_unlock_free;
+ }
+ ss_del(&s);
+
+ if (signal_pending(current)) {
+ err = -ERESTARTNOHAND;
+ goto out_unlock_free;
+ }
+ }
+
+ msq->q_lspid = task_tgid_vnr(current);
+ msq->q_stime = get_seconds();
+
+ if (!pipelined_send(msq, msg)) {
+ /* no one is waiting for this message, enqueue it */
+ list_add_tail(&msg->m_list, &msq->q_messages);
+ msq->q_cbytes += msgsz;
+ msq->q_qnum++;
+ atomic_add(msgsz, &ns->msg_bytes);
+ atomic_inc(&ns->msg_hdrs);
+ }
+
+ err = 0;
+ msg = NULL;
+
+out_unlock_free:
+ msg_unlock(msq);
+out_free:
+ if (msg != NULL)
+ free_msg(msg);
+ return err;
+}
+
+SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
+ int, msgflg)
+{
+ long mtype;
+
+ if (get_user(mtype, &msgp->mtype))
+ return -EFAULT;
+ return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
+}
+
+static inline int convert_mode(long *msgtyp, int msgflg)
+{
+ /*
+ * find message of correct type.
+ * msgtyp = 0 => get first.
+ * msgtyp > 0 => get first message of matching type.
+ * msgtyp < 0 => get message with least type must be < abs(msgtype).
+ */
+ if (*msgtyp == 0)
+ return SEARCH_ANY;
+ if (*msgtyp < 0) {
+ *msgtyp = -*msgtyp;
+ return SEARCH_LESSEQUAL;
+ }
+ if (msgflg & MSG_EXCEPT)
+ return SEARCH_NOTEQUAL;
+ return SEARCH_EQUAL;
+}
+
+long do_msgrcv(int msqid, long *pmtype, void __user *mtext,
+ size_t msgsz, long msgtyp, int msgflg)
+{
+ struct msg_queue *msq;
+ struct msg_msg *msg;
+ int mode;
+ struct ipc_namespace *ns;
+
+ if (msqid < 0 || (long) msgsz < 0)
+ return -EINVAL;
+ mode = convert_mode(&msgtyp, msgflg);
+ ns = current->nsproxy->ipc_ns;
+
+ msq = msg_lock_check(ns, msqid);
+ if (IS_ERR(msq))
+ return PTR_ERR(msq);
+
+ for (;;) {
+ struct msg_receiver msr_d;
+ struct list_head *tmp;
+
+ msg = ERR_PTR(-EACCES);
+ if (ipcperms(ns, &msq->q_perm, S_IRUGO))
+ goto out_unlock;
+
+ msg = ERR_PTR(-EAGAIN);
+ tmp = msq->q_messages.next;
+ while (tmp != &msq->q_messages) {
+ struct msg_msg *walk_msg;
+
+ walk_msg = list_entry(tmp, struct msg_msg, m_list);
+ if (testmsg(walk_msg, msgtyp, mode) &&
+ !security_msg_queue_msgrcv(msq, walk_msg, current,
+ msgtyp, mode)) {
+
+ msg = walk_msg;
+ if (mode == SEARCH_LESSEQUAL &&
+ walk_msg->m_type != 1) {
+ msg = walk_msg;
+ msgtyp = walk_msg->m_type - 1;
+ } else {
+ msg = walk_msg;
+ break;
+ }
+ }
+ tmp = tmp->next;
+ }
+ if (!IS_ERR(msg)) {
+ /*
+ * Found a suitable message.
+ * Unlink it from the queue.
+ */
+ if ((msgsz < msg->m_ts) && !(msgflg & MSG_NOERROR)) {
+ msg = ERR_PTR(-E2BIG);
+ goto out_unlock;
+ }
+ list_del(&msg->m_list);
+ msq->q_qnum--;
+ msq->q_rtime = get_seconds();
+ msq->q_lrpid = task_tgid_vnr(current);
+ msq->q_cbytes -= msg->m_ts;
+ atomic_sub(msg->m_ts, &ns->msg_bytes);
+ atomic_dec(&ns->msg_hdrs);
+ ss_wakeup(&msq->q_senders, 0);
+ msg_unlock(msq);
+ break;
+ }
+ /* No message waiting. Wait for a message */
+ if (msgflg & IPC_NOWAIT) {
+ msg = ERR_PTR(-ENOMSG);
+ goto out_unlock;
+ }
+ list_add_tail(&msr_d.r_list, &msq->q_receivers);
+ msr_d.r_tsk = current;
+ msr_d.r_msgtype = msgtyp;
+ msr_d.r_mode = mode;
+ if (msgflg & MSG_NOERROR)
+ msr_d.r_maxsize = INT_MAX;
+ else
+ msr_d.r_maxsize = msgsz;
+ msr_d.r_msg = ERR_PTR(-EAGAIN);
+ current->state = TASK_INTERRUPTIBLE;
+ msg_unlock(msq);
+
+ schedule();
+
+ /* Lockless receive, part 1:
+ * Disable preemption. We don't hold a reference to the queue
+ * and getting a reference would defeat the idea of a lockless
+ * operation, thus the code relies on rcu to guarantee the
+ * existence of msq:
+ * Prior to destruction, expunge_all(-EIRDM) changes r_msg.
+ * Thus if r_msg is -EAGAIN, then the queue not yet destroyed.
+ * rcu_read_lock() prevents preemption between reading r_msg
+ * and the spin_lock() inside ipc_lock_by_ptr().
+ */
+ rcu_read_lock();
+
+ /* Lockless receive, part 2:
+ * Wait until pipelined_send or expunge_all are outside of
+ * wake_up_process(). There is a race with exit(), see
+ * ipc/mqueue.c for the details.
+ */
+ msg = (struct msg_msg*)msr_d.r_msg;
+ while (msg == NULL) {
+ cpu_relax();
+ msg = (struct msg_msg *)msr_d.r_msg;
+ }
+
+ /* Lockless receive, part 3:
+ * If there is a message or an error then accept it without
+ * locking.
+ */
+ if (msg != ERR_PTR(-EAGAIN)) {
+ rcu_read_unlock();
+ break;
+ }
+
+ /* Lockless receive, part 3:
+ * Acquire the queue spinlock.
+ */
+ ipc_lock_by_ptr(&msq->q_perm);
+ rcu_read_unlock();
+
+ /* Lockless receive, part 4:
+ * Repeat test after acquiring the spinlock.
+ */
+ msg = (struct msg_msg*)msr_d.r_msg;
+ if (msg != ERR_PTR(-EAGAIN))
+ goto out_unlock;
+
+ list_del(&msr_d.r_list);
+ if (signal_pending(current)) {
+ msg = ERR_PTR(-ERESTARTNOHAND);
+out_unlock:
+ msg_unlock(msq);
+ break;
+ }
+ }
+ if (IS_ERR(msg))
+ return PTR_ERR(msg);
+
+ msgsz = (msgsz > msg->m_ts) ? msg->m_ts : msgsz;
+ *pmtype = msg->m_type;
+ if (store_msg(mtext, msg, msgsz))
+ msgsz = -EFAULT;
+
+ free_msg(msg);
+
+ return msgsz;
+}
+
+SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
+ long, msgtyp, int, msgflg)
+{
+ long err, mtype;
+
+ err = do_msgrcv(msqid, &mtype, msgp->mtext, msgsz, msgtyp, msgflg);
+ if (err < 0)
+ goto out;
+
+ if (put_user(mtype, &msgp->mtype))
+ err = -EFAULT;
+out:
+ return err;
+}
+
+#ifdef CONFIG_PROC_FS
+static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
+{
+ struct msg_queue *msq = it;
+
+ return seq_printf(s,
+ "%10d %10d %4o %10lu %10lu %5u %5u %5u %5u %5u %5u %10lu %10lu %10lu\n",
+ msq->q_perm.key,
+ msq->q_perm.id,
+ msq->q_perm.mode,
+ msq->q_cbytes,
+ msq->q_qnum,
+ msq->q_lspid,
+ msq->q_lrpid,
+ msq->q_perm.uid,
+ msq->q_perm.gid,
+ msq->q_perm.cuid,
+ msq->q_perm.cgid,
+ msq->q_stime,
+ msq->q_rtime,
+ msq->q_ctime);
+}
+#endif
diff --git a/ipc/msgutil.c b/ipc/msgutil.c
new file mode 100644
index 00000000..26143d37
--- /dev/null
+++ b/ipc/msgutil.c
@@ -0,0 +1,144 @@
+/*
+ * linux/ipc/msgutil.c
+ * Copyright (C) 1999, 2004 Manfred Spraul
+ *
+ * This file is released under GNU General Public Licence version 2 or
+ * (at your option) any later version.
+ *
+ * See the file COPYING for more details.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/security.h>
+#include <linux/slab.h>
+#include <linux/ipc.h>
+#include <linux/msg.h>
+#include <linux/ipc_namespace.h>
+#include <linux/utsname.h>
+#include <asm/uaccess.h>
+
+#include "util.h"
+
+DEFINE_SPINLOCK(mq_lock);
+
+/*
+ * The next 2 defines are here bc this is the only file
+ * compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE
+ * and not CONFIG_IPC_NS.
+ */
+struct ipc_namespace init_ipc_ns = {
+ .count = ATOMIC_INIT(1),
+ .user_ns = &init_user_ns,
+};
+
+atomic_t nr_ipc_ns = ATOMIC_INIT(1);
+
+struct msg_msgseg {
+ struct msg_msgseg* next;
+ /* the next part of the message follows immediately */
+};
+
+#define DATALEN_MSG (PAGE_SIZE-sizeof(struct msg_msg))
+#define DATALEN_SEG (PAGE_SIZE-sizeof(struct msg_msgseg))
+
+struct msg_msg *load_msg(const void __user *src, int len)
+{
+ struct msg_msg *msg;
+ struct msg_msgseg **pseg;
+ int err;
+ int alen;
+
+ alen = len;
+ if (alen > DATALEN_MSG)
+ alen = DATALEN_MSG;
+
+ msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL);
+ if (msg == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ msg->next = NULL;
+ msg->security = NULL;
+
+ if (copy_from_user(msg + 1, src, alen)) {
+ err = -EFAULT;
+ goto out_err;
+ }
+
+ len -= alen;
+ src = ((char __user *)src) + alen;
+ pseg = &msg->next;
+ while (len > 0) {
+ struct msg_msgseg *seg;
+ alen = len;
+ if (alen > DATALEN_SEG)
+ alen = DATALEN_SEG;
+ seg = kmalloc(sizeof(*seg) + alen,
+ GFP_KERNEL);
+ if (seg == NULL) {
+ err = -ENOMEM;
+ goto out_err;
+ }
+ *pseg = seg;
+ seg->next = NULL;
+ if (copy_from_user(seg + 1, src, alen)) {
+ err = -EFAULT;
+ goto out_err;
+ }
+ pseg = &seg->next;
+ len -= alen;
+ src = ((char __user *)src) + alen;
+ }
+
+ err = security_msg_msg_alloc(msg);
+ if (err)
+ goto out_err;
+
+ return msg;
+
+out_err:
+ free_msg(msg);
+ return ERR_PTR(err);
+}
+
+int store_msg(void __user *dest, struct msg_msg *msg, int len)
+{
+ int alen;
+ struct msg_msgseg *seg;
+
+ alen = len;
+ if (alen > DATALEN_MSG)
+ alen = DATALEN_MSG;
+ if (copy_to_user(dest, msg + 1, alen))
+ return -1;
+
+ len -= alen;
+ dest = ((char __user *)dest) + alen;
+ seg = msg->next;
+ while (len > 0) {
+ alen = len;
+ if (alen > DATALEN_SEG)
+ alen = DATALEN_SEG;
+ if (copy_to_user(dest, seg + 1, alen))
+ return -1;
+ len -= alen;
+ dest = ((char __user *)dest) + alen;
+ seg = seg->next;
+ }
+ return 0;
+}
+
+void free_msg(struct msg_msg *msg)
+{
+ struct msg_msgseg *seg;
+
+ security_msg_msg_free(msg);
+
+ seg = msg->next;
+ kfree(msg);
+ while (seg != NULL) {
+ struct msg_msgseg *tmp = seg->next;
+ kfree(seg);
+ seg = tmp;
+ }
+}
diff --git a/ipc/namespace.c b/ipc/namespace.c
new file mode 100644
index 00000000..ce0a6478
--- /dev/null
+++ b/ipc/namespace.c
@@ -0,0 +1,179 @@
+/*
+ * linux/ipc/namespace.c
+ * Copyright (C) 2006 Pavel Emelyanov <xemul@openvz.org> OpenVZ, SWsoft Inc.
+ */
+
+#include <linux/ipc.h>
+#include <linux/msg.h>
+#include <linux/ipc_namespace.h>
+#include <linux/rcupdate.h>
+#include <linux/nsproxy.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/user_namespace.h>
+#include <linux/proc_fs.h>
+
+#include "util.h"
+
+static struct ipc_namespace *create_ipc_ns(struct task_struct *tsk,
+ struct ipc_namespace *old_ns)
+{
+ struct ipc_namespace *ns;
+ int err;
+
+ ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL);
+ if (ns == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ atomic_set(&ns->count, 1);
+ err = mq_init_ns(ns);
+ if (err) {
+ kfree(ns);
+ return ERR_PTR(err);
+ }
+ atomic_inc(&nr_ipc_ns);
+
+ sem_init_ns(ns);
+ msg_init_ns(ns);
+ shm_init_ns(ns);
+
+ /*
+ * msgmni has already been computed for the new ipc ns.
+ * Thus, do the ipcns creation notification before registering that
+ * new ipcns in the chain.
+ */
+ ipcns_notify(IPCNS_CREATED);
+ register_ipcns_notifier(ns);
+
+ ns->user_ns = get_user_ns(task_cred_xxx(tsk, user)->user_ns);
+
+ return ns;
+}
+
+struct ipc_namespace *copy_ipcs(unsigned long flags,
+ struct task_struct *tsk)
+{
+ struct ipc_namespace *ns = tsk->nsproxy->ipc_ns;
+
+ if (!(flags & CLONE_NEWIPC))
+ return get_ipc_ns(ns);
+ return create_ipc_ns(tsk, ns);
+}
+
+/*
+ * free_ipcs - free all ipcs of one type
+ * @ns: the namespace to remove the ipcs from
+ * @ids: the table of ipcs to free
+ * @free: the function called to free each individual ipc
+ *
+ * Called for each kind of ipc when an ipc_namespace exits.
+ */
+void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
+ void (*free)(struct ipc_namespace *, struct kern_ipc_perm *))
+{
+ struct kern_ipc_perm *perm;
+ int next_id;
+ int total, in_use;
+
+ down_write(&ids->rw_mutex);
+
+ in_use = ids->in_use;
+
+ for (total = 0, next_id = 0; total < in_use; next_id++) {
+ perm = idr_find(&ids->ipcs_idr, next_id);
+ if (perm == NULL)
+ continue;
+ ipc_lock_by_ptr(perm);
+ free(ns, perm);
+ total++;
+ }
+ up_write(&ids->rw_mutex);
+}
+
+static void free_ipc_ns(struct ipc_namespace *ns)
+{
+ /*
+ * Unregistering the hotplug notifier at the beginning guarantees
+ * that the ipc namespace won't be freed while we are inside the
+ * callback routine. Since the blocking_notifier_chain_XXX routines
+ * hold a rw lock on the notifier list, unregister_ipcns_notifier()
+ * won't take the rw lock before blocking_notifier_call_chain() has
+ * released the rd lock.
+ */
+ unregister_ipcns_notifier(ns);
+ sem_exit_ns(ns);
+ msg_exit_ns(ns);
+ shm_exit_ns(ns);
+ atomic_dec(&nr_ipc_ns);
+
+ /*
+ * Do the ipcns removal notification after decrementing nr_ipc_ns in
+ * order to have a correct value when recomputing msgmni.
+ */
+ ipcns_notify(IPCNS_REMOVED);
+ put_user_ns(ns->user_ns);
+ kfree(ns);
+}
+
+/*
+ * put_ipc_ns - drop a reference to an ipc namespace.
+ * @ns: the namespace to put
+ *
+ * If this is the last task in the namespace exiting, and
+ * it is dropping the refcount to 0, then it can race with
+ * a task in another ipc namespace but in a mounts namespace
+ * which has this ipcns's mqueuefs mounted, doing some action
+ * with one of the mqueuefs files. That can raise the refcount.
+ * So dropping the refcount, and raising the refcount when
+ * accessing it through the VFS, are protected with mq_lock.
+ *
+ * (Clearly, a task raising the refcount on its own ipc_ns
+ * needn't take mq_lock since it can't race with the last task
+ * in the ipcns exiting).
+ */
+void put_ipc_ns(struct ipc_namespace *ns)
+{
+ if (atomic_dec_and_lock(&ns->count, &mq_lock)) {
+ mq_clear_sbinfo(ns);
+ spin_unlock(&mq_lock);
+ mq_put_mnt(ns);
+ free_ipc_ns(ns);
+ }
+}
+
+static void *ipcns_get(struct task_struct *task)
+{
+ struct ipc_namespace *ns = NULL;
+ struct nsproxy *nsproxy;
+
+ rcu_read_lock();
+ nsproxy = task_nsproxy(task);
+ if (nsproxy)
+ ns = get_ipc_ns(nsproxy->ipc_ns);
+ rcu_read_unlock();
+
+ return ns;
+}
+
+static void ipcns_put(void *ns)
+{
+ return put_ipc_ns(ns);
+}
+
+static int ipcns_install(struct nsproxy *nsproxy, void *ns)
+{
+ /* Ditch state from the old ipc namespace */
+ exit_sem(current);
+ put_ipc_ns(nsproxy->ipc_ns);
+ nsproxy->ipc_ns = get_ipc_ns(ns);
+ return 0;
+}
+
+const struct proc_ns_operations ipcns_operations = {
+ .name = "ipc",
+ .type = CLONE_NEWIPC,
+ .get = ipcns_get,
+ .put = ipcns_put,
+ .install = ipcns_install,
+};
diff --git a/ipc/sem.c b/ipc/sem.c
new file mode 100644
index 00000000..5215a814
--- /dev/null
+++ b/ipc/sem.c
@@ -0,0 +1,1695 @@
+/*
+ * linux/ipc/sem.c
+ * Copyright (C) 1992 Krishna Balasubramanian
+ * Copyright (C) 1995 Eric Schenk, Bruno Haible
+ *
+ * /proc/sysvipc/sem support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
+ *
+ * SMP-threaded, sysctl's added
+ * (c) 1999 Manfred Spraul <manfred@colorfullife.com>
+ * Enforced range limit on SEM_UNDO
+ * (c) 2001 Red Hat Inc
+ * Lockless wakeup
+ * (c) 2003 Manfred Spraul <manfred@colorfullife.com>
+ * Further wakeup optimizations, documentation
+ * (c) 2010 Manfred Spraul <manfred@colorfullife.com>
+ *
+ * support for audit of ipc object properties and permission changes
+ * Dustin Kirkland <dustin.kirkland@us.ibm.com>
+ *
+ * namespaces support
+ * OpenVZ, SWsoft Inc.
+ * Pavel Emelianov <xemul@openvz.org>
+ *
+ * Implementation notes: (May 2010)
+ * This file implements System V semaphores.
+ *
+ * User space visible behavior:
+ * - FIFO ordering for semop() operations (just FIFO, not starvation
+ * protection)
+ * - multiple semaphore operations that alter the same semaphore in
+ * one semop() are handled.
+ * - sem_ctime (time of last semctl()) is updated in the IPC_SET, SETVAL and
+ * SETALL calls.
+ * - two Linux specific semctl() commands: SEM_STAT, SEM_INFO.
+ * - undo adjustments at process exit are limited to 0..SEMVMX.
+ * - namespace are supported.
+ * - SEMMSL, SEMMNS, SEMOPM and SEMMNI can be configured at runtine by writing
+ * to /proc/sys/kernel/sem.
+ * - statistics about the usage are reported in /proc/sysvipc/sem.
+ *
+ * Internals:
+ * - scalability:
+ * - all global variables are read-mostly.
+ * - semop() calls and semctl(RMID) are synchronized by RCU.
+ * - most operations do write operations (actually: spin_lock calls) to
+ * the per-semaphore array structure.
+ * Thus: Perfect SMP scaling between independent semaphore arrays.
+ * If multiple semaphores in one array are used, then cache line
+ * trashing on the semaphore array spinlock will limit the scaling.
+ * - semncnt and semzcnt are calculated on demand in count_semncnt() and
+ * count_semzcnt()
+ * - the task that performs a successful semop() scans the list of all
+ * sleeping tasks and completes any pending operations that can be fulfilled.
+ * Semaphores are actively given to waiting tasks (necessary for FIFO).
+ * (see update_queue())
+ * - To improve the scalability, the actual wake-up calls are performed after
+ * dropping all locks. (see wake_up_sem_queue_prepare(),
+ * wake_up_sem_queue_do())
+ * - All work is done by the waker, the woken up task does not have to do
+ * anything - not even acquiring a lock or dropping a refcount.
+ * - A woken up task may not even touch the semaphore array anymore, it may
+ * have been destroyed already by a semctl(RMID).
+ * - The synchronizations between wake-ups due to a timeout/signal and a
+ * wake-up due to a completed semaphore operation is achieved by using an
+ * intermediate state (IN_WAKEUP).
+ * - UNDO values are stored in an array (one per process and per
+ * semaphore array, lazily allocated). For backwards compatibility, multiple
+ * modes for the UNDO variables are supported (per process, per thread)
+ * (see copy_semundo, CLONE_SYSVSEM)
+ * - There are two lists of the pending operations: a per-array list
+ * and per-semaphore list (stored in the array). This allows to achieve FIFO
+ * ordering without always scanning all pending operations.
+ * The worst-case behavior is nevertheless O(N^2) for N wakeups.
+ */
+
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/time.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/audit.h>
+#include <linux/capability.h>
+#include <linux/seq_file.h>
+#include <linux/rwsem.h>
+#include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
+
+#include <asm/uaccess.h>
+#include "util.h"
+
+/* One semaphore structure for each semaphore in the system. */
+struct sem {
+ int semval; /* current value */
+ int sempid; /* pid of last operation */
+ struct list_head sem_pending; /* pending single-sop operations */
+};
+
+/* One queue for each sleeping process in the system. */
+struct sem_queue {
+ struct list_head simple_list; /* queue of pending operations */
+ struct list_head list; /* queue of pending operations */
+ struct task_struct *sleeper; /* this process */
+ struct sem_undo *undo; /* undo structure */
+ int pid; /* process id of requesting process */
+ int status; /* completion status of operation */
+ struct sembuf *sops; /* array of pending operations */
+ int nsops; /* number of operations */
+ int alter; /* does *sops alter the array? */
+};
+
+/* Each task has a list of undo requests. They are executed automatically
+ * when the process exits.
+ */
+struct sem_undo {
+ struct list_head list_proc; /* per-process list: *
+ * all undos from one process
+ * rcu protected */
+ struct rcu_head rcu; /* rcu struct for sem_undo */
+ struct sem_undo_list *ulp; /* back ptr to sem_undo_list */
+ struct list_head list_id; /* per semaphore array list:
+ * all undos for one array */
+ int semid; /* semaphore set identifier */
+ short *semadj; /* array of adjustments */
+ /* one per semaphore */
+};
+
+/* sem_undo_list controls shared access to the list of sem_undo structures
+ * that may be shared among all a CLONE_SYSVSEM task group.
+ */
+struct sem_undo_list {
+ atomic_t refcnt;
+ spinlock_t lock;
+ struct list_head list_proc;
+};
+
+
+#define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS])
+
+#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm)
+#define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid)
+
+static int newary(struct ipc_namespace *, struct ipc_params *);
+static void freeary(struct ipc_namespace *, struct kern_ipc_perm *);
+#ifdef CONFIG_PROC_FS
+static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
+#endif
+
+#define SEMMSL_FAST 256 /* 512 bytes on stack */
+#define SEMOPM_FAST 64 /* ~ 372 bytes on stack */
+
+/*
+ * linked list protection:
+ * sem_undo.id_next,
+ * sem_array.sem_pending{,last},
+ * sem_array.sem_undo: sem_lock() for read/write
+ * sem_undo.proc_next: only "current" is allowed to read/write that field.
+ *
+ */
+
+#define sc_semmsl sem_ctls[0]
+#define sc_semmns sem_ctls[1]
+#define sc_semopm sem_ctls[2]
+#define sc_semmni sem_ctls[3]
+
+void sem_init_ns(struct ipc_namespace *ns)
+{
+ ns->sc_semmsl = SEMMSL;
+ ns->sc_semmns = SEMMNS;
+ ns->sc_semopm = SEMOPM;
+ ns->sc_semmni = SEMMNI;
+ ns->used_sems = 0;
+ ipc_init_ids(&ns->ids[IPC_SEM_IDS]);
+}
+
+#ifdef CONFIG_IPC_NS
+void sem_exit_ns(struct ipc_namespace *ns)
+{
+ free_ipcs(ns, &sem_ids(ns), freeary);
+ idr_destroy(&ns->ids[IPC_SEM_IDS].ipcs_idr);
+}
+#endif
+
+void __init sem_init (void)
+{
+ sem_init_ns(&init_ipc_ns);
+ ipc_init_proc_interface("sysvipc/sem",
+ " key semid perms nsems uid gid cuid cgid otime ctime\n",
+ IPC_SEM_IDS, sysvipc_sem_proc_show);
+}
+
+/*
+ * sem_lock_(check_) routines are called in the paths where the rw_mutex
+ * is not held.
+ */
+static inline struct sem_array *sem_lock(struct ipc_namespace *ns, int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_lock(&sem_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct sem_array *)ipcp;
+
+ return container_of(ipcp, struct sem_array, sem_perm);
+}
+
+static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns,
+ int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct sem_array *)ipcp;
+
+ return container_of(ipcp, struct sem_array, sem_perm);
+}
+
+static inline void sem_lock_and_putref(struct sem_array *sma)
+{
+ ipc_lock_by_ptr(&sma->sem_perm);
+ ipc_rcu_putref(sma);
+}
+
+static inline void sem_getref_and_unlock(struct sem_array *sma)
+{
+ ipc_rcu_getref(sma);
+ ipc_unlock(&(sma)->sem_perm);
+}
+
+static inline void sem_putref(struct sem_array *sma)
+{
+ ipc_lock_by_ptr(&sma->sem_perm);
+ ipc_rcu_putref(sma);
+ ipc_unlock(&(sma)->sem_perm);
+}
+
+static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
+{
+ ipc_rmid(&sem_ids(ns), &s->sem_perm);
+}
+
+/*
+ * Lockless wakeup algorithm:
+ * Without the check/retry algorithm a lockless wakeup is possible:
+ * - queue.status is initialized to -EINTR before blocking.
+ * - wakeup is performed by
+ * * unlinking the queue entry from sma->sem_pending
+ * * setting queue.status to IN_WAKEUP
+ * This is the notification for the blocked thread that a
+ * result value is imminent.
+ * * call wake_up_process
+ * * set queue.status to the final value.
+ * - the previously blocked thread checks queue.status:
+ * * if it's IN_WAKEUP, then it must wait until the value changes
+ * * if it's not -EINTR, then the operation was completed by
+ * update_queue. semtimedop can return queue.status without
+ * performing any operation on the sem array.
+ * * otherwise it must acquire the spinlock and check what's up.
+ *
+ * The two-stage algorithm is necessary to protect against the following
+ * races:
+ * - if queue.status is set after wake_up_process, then the woken up idle
+ * thread could race forward and try (and fail) to acquire sma->lock
+ * before update_queue had a chance to set queue.status
+ * - if queue.status is written before wake_up_process and if the
+ * blocked process is woken up by a signal between writing
+ * queue.status and the wake_up_process, then the woken up
+ * process could return from semtimedop and die by calling
+ * sys_exit before wake_up_process is called. Then wake_up_process
+ * will oops, because the task structure is already invalid.
+ * (yes, this happened on s390 with sysv msg).
+ *
+ */
+#define IN_WAKEUP 1
+
+/**
+ * newary - Create a new semaphore set
+ * @ns: namespace
+ * @params: ptr to the structure that contains key, semflg and nsems
+ *
+ * Called with sem_ids.rw_mutex held (as a writer)
+ */
+
+static int newary(struct ipc_namespace *ns, struct ipc_params *params)
+{
+ int id;
+ int retval;
+ struct sem_array *sma;
+ int size;
+ key_t key = params->key;
+ int nsems = params->u.nsems;
+ int semflg = params->flg;
+ int i;
+
+ if (!nsems)
+ return -EINVAL;
+ if (ns->used_sems + nsems > ns->sc_semmns)
+ return -ENOSPC;
+
+ size = sizeof (*sma) + nsems * sizeof (struct sem);
+ sma = ipc_rcu_alloc(size);
+ if (!sma) {
+ return -ENOMEM;
+ }
+ memset (sma, 0, size);
+
+ sma->sem_perm.mode = (semflg & S_IRWXUGO);
+ sma->sem_perm.key = key;
+
+ sma->sem_perm.security = NULL;
+ retval = security_sem_alloc(sma);
+ if (retval) {
+ ipc_rcu_putref(sma);
+ return retval;
+ }
+
+ id = ipc_addid(&sem_ids(ns), &sma->sem_perm, ns->sc_semmni);
+ if (id < 0) {
+ security_sem_free(sma);
+ ipc_rcu_putref(sma);
+ return id;
+ }
+ ns->used_sems += nsems;
+
+ sma->sem_base = (struct sem *) &sma[1];
+
+ for (i = 0; i < nsems; i++)
+ INIT_LIST_HEAD(&sma->sem_base[i].sem_pending);
+
+ sma->complex_count = 0;
+ INIT_LIST_HEAD(&sma->sem_pending);
+ INIT_LIST_HEAD(&sma->list_id);
+ sma->sem_nsems = nsems;
+ sma->sem_ctime = get_seconds();
+ sem_unlock(sma);
+
+ return sma->sem_perm.id;
+}
+
+
+/*
+ * Called with sem_ids.rw_mutex and ipcp locked.
+ */
+static inline int sem_security(struct kern_ipc_perm *ipcp, int semflg)
+{
+ struct sem_array *sma;
+
+ sma = container_of(ipcp, struct sem_array, sem_perm);
+ return security_sem_associate(sma, semflg);
+}
+
+/*
+ * Called with sem_ids.rw_mutex and ipcp locked.
+ */
+static inline int sem_more_checks(struct kern_ipc_perm *ipcp,
+ struct ipc_params *params)
+{
+ struct sem_array *sma;
+
+ sma = container_of(ipcp, struct sem_array, sem_perm);
+ if (params->u.nsems > sma->sem_nsems)
+ return -EINVAL;
+
+ return 0;
+}
+
+SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg)
+{
+ struct ipc_namespace *ns;
+ struct ipc_ops sem_ops;
+ struct ipc_params sem_params;
+
+ ns = current->nsproxy->ipc_ns;
+
+ if (nsems < 0 || nsems > ns->sc_semmsl)
+ return -EINVAL;
+
+ sem_ops.getnew = newary;
+ sem_ops.associate = sem_security;
+ sem_ops.more_checks = sem_more_checks;
+
+ sem_params.key = key;
+ sem_params.flg = semflg;
+ sem_params.u.nsems = nsems;
+
+ return ipcget(ns, &sem_ids(ns), &sem_ops, &sem_params);
+}
+
+/*
+ * Determine whether a sequence of semaphore operations would succeed
+ * all at once. Return 0 if yes, 1 if need to sleep, else return error code.
+ */
+
+static int try_atomic_semop (struct sem_array * sma, struct sembuf * sops,
+ int nsops, struct sem_undo *un, int pid)
+{
+ int result, sem_op;
+ struct sembuf *sop;
+ struct sem * curr;
+
+ for (sop = sops; sop < sops + nsops; sop++) {
+ curr = sma->sem_base + sop->sem_num;
+ sem_op = sop->sem_op;
+ result = curr->semval;
+
+ if (!sem_op && result)
+ goto would_block;
+
+ result += sem_op;
+ if (result < 0)
+ goto would_block;
+ if (result > SEMVMX)
+ goto out_of_range;
+ if (sop->sem_flg & SEM_UNDO) {
+ int undo = un->semadj[sop->sem_num] - sem_op;
+ /*
+ * Exceeding the undo range is an error.
+ */
+ if (undo < (-SEMAEM - 1) || undo > SEMAEM)
+ goto out_of_range;
+ }
+ curr->semval = result;
+ }
+
+ sop--;
+ while (sop >= sops) {
+ sma->sem_base[sop->sem_num].sempid = pid;
+ if (sop->sem_flg & SEM_UNDO)
+ un->semadj[sop->sem_num] -= sop->sem_op;
+ sop--;
+ }
+
+ return 0;
+
+out_of_range:
+ result = -ERANGE;
+ goto undo;
+
+would_block:
+ if (sop->sem_flg & IPC_NOWAIT)
+ result = -EAGAIN;
+ else
+ result = 1;
+
+undo:
+ sop--;
+ while (sop >= sops) {
+ sma->sem_base[sop->sem_num].semval -= sop->sem_op;
+ sop--;
+ }
+
+ return result;
+}
+
+/** wake_up_sem_queue_prepare(q, error): Prepare wake-up
+ * @q: queue entry that must be signaled
+ * @error: Error value for the signal
+ *
+ * Prepare the wake-up of the queue entry q.
+ */
+static void wake_up_sem_queue_prepare(struct list_head *pt,
+ struct sem_queue *q, int error)
+{
+ if (list_empty(pt)) {
+ /*
+ * Hold preempt off so that we don't get preempted and have the
+ * wakee busy-wait until we're scheduled back on.
+ */
+ preempt_disable();
+ }
+ q->status = IN_WAKEUP;
+ q->pid = error;
+
+ list_add_tail(&q->simple_list, pt);
+}
+
+/**
+ * wake_up_sem_queue_do(pt) - do the actual wake-up
+ * @pt: list of tasks to be woken up
+ *
+ * Do the actual wake-up.
+ * The function is called without any locks held, thus the semaphore array
+ * could be destroyed already and the tasks can disappear as soon as the
+ * status is set to the actual return code.
+ */
+static void wake_up_sem_queue_do(struct list_head *pt)
+{
+ struct sem_queue *q, *t;
+ int did_something;
+
+ did_something = !list_empty(pt);
+ list_for_each_entry_safe(q, t, pt, simple_list) {
+ wake_up_process(q->sleeper);
+ /* q can disappear immediately after writing q->status. */
+ smp_wmb();
+ q->status = q->pid;
+ }
+ if (did_something)
+ preempt_enable();
+}
+
+static void unlink_queue(struct sem_array *sma, struct sem_queue *q)
+{
+ list_del(&q->list);
+ if (q->nsops == 1)
+ list_del(&q->simple_list);
+ else
+ sma->complex_count--;
+}
+
+/** check_restart(sma, q)
+ * @sma: semaphore array
+ * @q: the operation that just completed
+ *
+ * update_queue is O(N^2) when it restarts scanning the whole queue of
+ * waiting operations. Therefore this function checks if the restart is
+ * really necessary. It is called after a previously waiting operation
+ * was completed.
+ */
+static int check_restart(struct sem_array *sma, struct sem_queue *q)
+{
+ struct sem *curr;
+ struct sem_queue *h;
+
+ /* if the operation didn't modify the array, then no restart */
+ if (q->alter == 0)
+ return 0;
+
+ /* pending complex operations are too difficult to analyse */
+ if (sma->complex_count)
+ return 1;
+
+ /* we were a sleeping complex operation. Too difficult */
+ if (q->nsops > 1)
+ return 1;
+
+ curr = sma->sem_base + q->sops[0].sem_num;
+
+ /* No-one waits on this queue */
+ if (list_empty(&curr->sem_pending))
+ return 0;
+
+ /* the new semaphore value */
+ if (curr->semval) {
+ /* It is impossible that someone waits for the new value:
+ * - q is a previously sleeping simple operation that
+ * altered the array. It must be a decrement, because
+ * simple increments never sleep.
+ * - The value is not 0, thus wait-for-zero won't proceed.
+ * - If there are older (higher priority) decrements
+ * in the queue, then they have observed the original
+ * semval value and couldn't proceed. The operation
+ * decremented to value - thus they won't proceed either.
+ */
+ BUG_ON(q->sops[0].sem_op >= 0);
+ return 0;
+ }
+ /*
+ * semval is 0. Check if there are wait-for-zero semops.
+ * They must be the first entries in the per-semaphore simple queue
+ */
+ h = list_first_entry(&curr->sem_pending, struct sem_queue, simple_list);
+ BUG_ON(h->nsops != 1);
+ BUG_ON(h->sops[0].sem_num != q->sops[0].sem_num);
+
+ /* Yes, there is a wait-for-zero semop. Restart */
+ if (h->sops[0].sem_op == 0)
+ return 1;
+
+ /* Again - no-one is waiting for the new value. */
+ return 0;
+}
+
+
+/**
+ * update_queue(sma, semnum): Look for tasks that can be completed.
+ * @sma: semaphore array.
+ * @semnum: semaphore that was modified.
+ * @pt: list head for the tasks that must be woken up.
+ *
+ * update_queue must be called after a semaphore in a semaphore array
+ * was modified. If multiple semaphore were modified, then @semnum
+ * must be set to -1.
+ * The tasks that must be woken up are added to @pt. The return code
+ * is stored in q->pid.
+ * The function return 1 if at least one semop was completed successfully.
+ */
+static int update_queue(struct sem_array *sma, int semnum, struct list_head *pt)
+{
+ struct sem_queue *q;
+ struct list_head *walk;
+ struct list_head *pending_list;
+ int offset;
+ int semop_completed = 0;
+
+ /* if there are complex operations around, then knowing the semaphore
+ * that was modified doesn't help us. Assume that multiple semaphores
+ * were modified.
+ */
+ if (sma->complex_count)
+ semnum = -1;
+
+ if (semnum == -1) {
+ pending_list = &sma->sem_pending;
+ offset = offsetof(struct sem_queue, list);
+ } else {
+ pending_list = &sma->sem_base[semnum].sem_pending;
+ offset = offsetof(struct sem_queue, simple_list);
+ }
+
+again:
+ walk = pending_list->next;
+ while (walk != pending_list) {
+ int error, restart;
+
+ q = (struct sem_queue *)((char *)walk - offset);
+ walk = walk->next;
+
+ /* If we are scanning the single sop, per-semaphore list of
+ * one semaphore and that semaphore is 0, then it is not
+ * necessary to scan the "alter" entries: simple increments
+ * that affect only one entry succeed immediately and cannot
+ * be in the per semaphore pending queue, and decrements
+ * cannot be successful if the value is already 0.
+ */
+ if (semnum != -1 && sma->sem_base[semnum].semval == 0 &&
+ q->alter)
+ break;
+
+ error = try_atomic_semop(sma, q->sops, q->nsops,
+ q->undo, q->pid);
+
+ /* Does q->sleeper still need to sleep? */
+ if (error > 0)
+ continue;
+
+ unlink_queue(sma, q);
+
+ if (error) {
+ restart = 0;
+ } else {
+ semop_completed = 1;
+ restart = check_restart(sma, q);
+ }
+
+ wake_up_sem_queue_prepare(pt, q, error);
+ if (restart)
+ goto again;
+ }
+ return semop_completed;
+}
+
+/**
+ * do_smart_update(sma, sops, nsops, otime, pt) - optimized update_queue
+ * @sma: semaphore array
+ * @sops: operations that were performed
+ * @nsops: number of operations
+ * @otime: force setting otime
+ * @pt: list head of the tasks that must be woken up.
+ *
+ * do_smart_update() does the required called to update_queue, based on the
+ * actual changes that were performed on the semaphore array.
+ * Note that the function does not do the actual wake-up: the caller is
+ * responsible for calling wake_up_sem_queue_do(@pt).
+ * It is safe to perform this call after dropping all locks.
+ */
+static void do_smart_update(struct sem_array *sma, struct sembuf *sops, int nsops,
+ int otime, struct list_head *pt)
+{
+ int i;
+
+ if (sma->complex_count || sops == NULL) {
+ if (update_queue(sma, -1, pt))
+ otime = 1;
+ goto done;
+ }
+
+ for (i = 0; i < nsops; i++) {
+ if (sops[i].sem_op > 0 ||
+ (sops[i].sem_op < 0 &&
+ sma->sem_base[sops[i].sem_num].semval == 0))
+ if (update_queue(sma, sops[i].sem_num, pt))
+ otime = 1;
+ }
+done:
+ if (otime)
+ sma->sem_otime = get_seconds();
+}
+
+
+/* The following counts are associated to each semaphore:
+ * semncnt number of tasks waiting on semval being nonzero
+ * semzcnt number of tasks waiting on semval being zero
+ * This model assumes that a task waits on exactly one semaphore.
+ * Since semaphore operations are to be performed atomically, tasks actually
+ * wait on a whole sequence of semaphores simultaneously.
+ * The counts we return here are a rough approximation, but still
+ * warrant that semncnt+semzcnt>0 if the task is on the pending queue.
+ */
+static int count_semncnt (struct sem_array * sma, ushort semnum)
+{
+ int semncnt;
+ struct sem_queue * q;
+
+ semncnt = 0;
+ list_for_each_entry(q, &sma->sem_pending, list) {
+ struct sembuf * sops = q->sops;
+ int nsops = q->nsops;
+ int i;
+ for (i = 0; i < nsops; i++)
+ if (sops[i].sem_num == semnum
+ && (sops[i].sem_op < 0)
+ && !(sops[i].sem_flg & IPC_NOWAIT))
+ semncnt++;
+ }
+ return semncnt;
+}
+
+static int count_semzcnt (struct sem_array * sma, ushort semnum)
+{
+ int semzcnt;
+ struct sem_queue * q;
+
+ semzcnt = 0;
+ list_for_each_entry(q, &sma->sem_pending, list) {
+ struct sembuf * sops = q->sops;
+ int nsops = q->nsops;
+ int i;
+ for (i = 0; i < nsops; i++)
+ if (sops[i].sem_num == semnum
+ && (sops[i].sem_op == 0)
+ && !(sops[i].sem_flg & IPC_NOWAIT))
+ semzcnt++;
+ }
+ return semzcnt;
+}
+
+/* Free a semaphore set. freeary() is called with sem_ids.rw_mutex locked
+ * as a writer and the spinlock for this semaphore set hold. sem_ids.rw_mutex
+ * remains locked on exit.
+ */
+static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
+{
+ struct sem_undo *un, *tu;
+ struct sem_queue *q, *tq;
+ struct sem_array *sma = container_of(ipcp, struct sem_array, sem_perm);
+ struct list_head tasks;
+
+ /* Free the existing undo structures for this semaphore set. */
+ assert_spin_locked(&sma->sem_perm.lock);
+ list_for_each_entry_safe(un, tu, &sma->list_id, list_id) {
+ list_del(&un->list_id);
+ spin_lock(&un->ulp->lock);
+ un->semid = -1;
+ list_del_rcu(&un->list_proc);
+ spin_unlock(&un->ulp->lock);
+ kfree_rcu(un, rcu);
+ }
+
+ /* Wake up all pending processes and let them fail with EIDRM. */
+ INIT_LIST_HEAD(&tasks);
+ list_for_each_entry_safe(q, tq, &sma->sem_pending, list) {
+ unlink_queue(sma, q);
+ wake_up_sem_queue_prepare(&tasks, q, -EIDRM);
+ }
+
+ /* Remove the semaphore set from the IDR */
+ sem_rmid(ns, sma);
+ sem_unlock(sma);
+
+ wake_up_sem_queue_do(&tasks);
+ ns->used_sems -= sma->sem_nsems;
+ security_sem_free(sma);
+ ipc_rcu_putref(sma);
+}
+
+static unsigned long copy_semid_to_user(void __user *buf, struct semid64_ds *in, int version)
+{
+ switch(version) {
+ case IPC_64:
+ return copy_to_user(buf, in, sizeof(*in));
+ case IPC_OLD:
+ {
+ struct semid_ds out;
+
+ memset(&out, 0, sizeof(out));
+
+ ipc64_perm_to_ipc_perm(&in->sem_perm, &out.sem_perm);
+
+ out.sem_otime = in->sem_otime;
+ out.sem_ctime = in->sem_ctime;
+ out.sem_nsems = in->sem_nsems;
+
+ return copy_to_user(buf, &out, sizeof(out));
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static int semctl_nolock(struct ipc_namespace *ns, int semid,
+ int cmd, int version, union semun arg)
+{
+ int err;
+ struct sem_array *sma;
+
+ switch(cmd) {
+ case IPC_INFO:
+ case SEM_INFO:
+ {
+ struct seminfo seminfo;
+ int max_id;
+
+ err = security_sem_semctl(NULL, cmd);
+ if (err)
+ return err;
+
+ memset(&seminfo,0,sizeof(seminfo));
+ seminfo.semmni = ns->sc_semmni;
+ seminfo.semmns = ns->sc_semmns;
+ seminfo.semmsl = ns->sc_semmsl;
+ seminfo.semopm = ns->sc_semopm;
+ seminfo.semvmx = SEMVMX;
+ seminfo.semmnu = SEMMNU;
+ seminfo.semmap = SEMMAP;
+ seminfo.semume = SEMUME;
+ down_read(&sem_ids(ns).rw_mutex);
+ if (cmd == SEM_INFO) {
+ seminfo.semusz = sem_ids(ns).in_use;
+ seminfo.semaem = ns->used_sems;
+ } else {
+ seminfo.semusz = SEMUSZ;
+ seminfo.semaem = SEMAEM;
+ }
+ max_id = ipc_get_maxid(&sem_ids(ns));
+ up_read(&sem_ids(ns).rw_mutex);
+ if (copy_to_user (arg.__buf, &seminfo, sizeof(struct seminfo)))
+ return -EFAULT;
+ return (max_id < 0) ? 0: max_id;
+ }
+ case IPC_STAT:
+ case SEM_STAT:
+ {
+ struct semid64_ds tbuf;
+ int id;
+
+ if (cmd == SEM_STAT) {
+ sma = sem_lock(ns, semid);
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
+ id = sma->sem_perm.id;
+ } else {
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
+ id = 0;
+ }
+
+ err = -EACCES;
+ if (ipcperms(ns, &sma->sem_perm, S_IRUGO))
+ goto out_unlock;
+
+ err = security_sem_semctl(sma, cmd);
+ if (err)
+ goto out_unlock;
+
+ memset(&tbuf, 0, sizeof(tbuf));
+
+ kernel_to_ipc64_perm(&sma->sem_perm, &tbuf.sem_perm);
+ tbuf.sem_otime = sma->sem_otime;
+ tbuf.sem_ctime = sma->sem_ctime;
+ tbuf.sem_nsems = sma->sem_nsems;
+ sem_unlock(sma);
+ if (copy_semid_to_user (arg.buf, &tbuf, version))
+ return -EFAULT;
+ return id;
+ }
+ default:
+ return -EINVAL;
+ }
+out_unlock:
+ sem_unlock(sma);
+ return err;
+}
+
+static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
+ int cmd, int version, union semun arg)
+{
+ struct sem_array *sma;
+ struct sem* curr;
+ int err;
+ ushort fast_sem_io[SEMMSL_FAST];
+ ushort* sem_io = fast_sem_io;
+ int nsems;
+ struct list_head tasks;
+
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
+
+ INIT_LIST_HEAD(&tasks);
+ nsems = sma->sem_nsems;
+
+ err = -EACCES;
+ if (ipcperms(ns, &sma->sem_perm,
+ (cmd == SETVAL || cmd == SETALL) ? S_IWUGO : S_IRUGO))
+ goto out_unlock;
+
+ err = security_sem_semctl(sma, cmd);
+ if (err)
+ goto out_unlock;
+
+ err = -EACCES;
+ switch (cmd) {
+ case GETALL:
+ {
+ ushort __user *array = arg.array;
+ int i;
+
+ if(nsems > SEMMSL_FAST) {
+ sem_getref_and_unlock(sma);
+
+ sem_io = ipc_alloc(sizeof(ushort)*nsems);
+ if(sem_io == NULL) {
+ sem_putref(sma);
+ return -ENOMEM;
+ }
+
+ sem_lock_and_putref(sma);
+ if (sma->sem_perm.deleted) {
+ sem_unlock(sma);
+ err = -EIDRM;
+ goto out_free;
+ }
+ }
+
+ for (i = 0; i < sma->sem_nsems; i++)
+ sem_io[i] = sma->sem_base[i].semval;
+ sem_unlock(sma);
+ err = 0;
+ if(copy_to_user(array, sem_io, nsems*sizeof(ushort)))
+ err = -EFAULT;
+ goto out_free;
+ }
+ case SETALL:
+ {
+ int i;
+ struct sem_undo *un;
+
+ sem_getref_and_unlock(sma);
+
+ if(nsems > SEMMSL_FAST) {
+ sem_io = ipc_alloc(sizeof(ushort)*nsems);
+ if(sem_io == NULL) {
+ sem_putref(sma);
+ return -ENOMEM;
+ }
+ }
+
+ if (copy_from_user (sem_io, arg.array, nsems*sizeof(ushort))) {
+ sem_putref(sma);
+ err = -EFAULT;
+ goto out_free;
+ }
+
+ for (i = 0; i < nsems; i++) {
+ if (sem_io[i] > SEMVMX) {
+ sem_putref(sma);
+ err = -ERANGE;
+ goto out_free;
+ }
+ }
+ sem_lock_and_putref(sma);
+ if (sma->sem_perm.deleted) {
+ sem_unlock(sma);
+ err = -EIDRM;
+ goto out_free;
+ }
+
+ for (i = 0; i < nsems; i++)
+ sma->sem_base[i].semval = sem_io[i];
+
+ assert_spin_locked(&sma->sem_perm.lock);
+ list_for_each_entry(un, &sma->list_id, list_id) {
+ for (i = 0; i < nsems; i++)
+ un->semadj[i] = 0;
+ }
+ sma->sem_ctime = get_seconds();
+ /* maybe some queued-up processes were waiting for this */
+ do_smart_update(sma, NULL, 0, 0, &tasks);
+ err = 0;
+ goto out_unlock;
+ }
+ /* GETVAL, GETPID, GETNCTN, GETZCNT, SETVAL: fall-through */
+ }
+ err = -EINVAL;
+ if(semnum < 0 || semnum >= nsems)
+ goto out_unlock;
+
+ curr = &sma->sem_base[semnum];
+
+ switch (cmd) {
+ case GETVAL:
+ err = curr->semval;
+ goto out_unlock;
+ case GETPID:
+ err = curr->sempid;
+ goto out_unlock;
+ case GETNCNT:
+ err = count_semncnt(sma,semnum);
+ goto out_unlock;
+ case GETZCNT:
+ err = count_semzcnt(sma,semnum);
+ goto out_unlock;
+ case SETVAL:
+ {
+ int val = arg.val;
+ struct sem_undo *un;
+
+ err = -ERANGE;
+ if (val > SEMVMX || val < 0)
+ goto out_unlock;
+
+ assert_spin_locked(&sma->sem_perm.lock);
+ list_for_each_entry(un, &sma->list_id, list_id)
+ un->semadj[semnum] = 0;
+
+ curr->semval = val;
+ curr->sempid = task_tgid_vnr(current);
+ sma->sem_ctime = get_seconds();
+ /* maybe some queued-up processes were waiting for this */
+ do_smart_update(sma, NULL, 0, 0, &tasks);
+ err = 0;
+ goto out_unlock;
+ }
+ }
+out_unlock:
+ sem_unlock(sma);
+ wake_up_sem_queue_do(&tasks);
+
+out_free:
+ if(sem_io != fast_sem_io)
+ ipc_free(sem_io, sizeof(ushort)*nsems);
+ return err;
+}
+
+static inline unsigned long
+copy_semid_from_user(struct semid64_ds *out, void __user *buf, int version)
+{
+ switch(version) {
+ case IPC_64:
+ if (copy_from_user(out, buf, sizeof(*out)))
+ return -EFAULT;
+ return 0;
+ case IPC_OLD:
+ {
+ struct semid_ds tbuf_old;
+
+ if(copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
+ return -EFAULT;
+
+ out->sem_perm.uid = tbuf_old.sem_perm.uid;
+ out->sem_perm.gid = tbuf_old.sem_perm.gid;
+ out->sem_perm.mode = tbuf_old.sem_perm.mode;
+
+ return 0;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+/*
+ * This function handles some semctl commands which require the rw_mutex
+ * to be held in write mode.
+ * NOTE: no locks must be held, the rw_mutex is taken inside this function.
+ */
+static int semctl_down(struct ipc_namespace *ns, int semid,
+ int cmd, int version, union semun arg)
+{
+ struct sem_array *sma;
+ int err;
+ struct semid64_ds semid64;
+ struct kern_ipc_perm *ipcp;
+
+ if(cmd == IPC_SET) {
+ if (copy_semid_from_user(&semid64, arg.buf, version))
+ return -EFAULT;
+ }
+
+ ipcp = ipcctl_pre_down(ns, &sem_ids(ns), semid, cmd,
+ &semid64.sem_perm, 0);
+ if (IS_ERR(ipcp))
+ return PTR_ERR(ipcp);
+
+ sma = container_of(ipcp, struct sem_array, sem_perm);
+
+ err = security_sem_semctl(sma, cmd);
+ if (err)
+ goto out_unlock;
+
+ switch(cmd){
+ case IPC_RMID:
+ freeary(ns, ipcp);
+ goto out_up;
+ case IPC_SET:
+ ipc_update_perm(&semid64.sem_perm, ipcp);
+ sma->sem_ctime = get_seconds();
+ break;
+ default:
+ err = -EINVAL;
+ }
+
+out_unlock:
+ sem_unlock(sma);
+out_up:
+ up_write(&sem_ids(ns).rw_mutex);
+ return err;
+}
+
+SYSCALL_DEFINE(semctl)(int semid, int semnum, int cmd, union semun arg)
+{
+ int err = -EINVAL;
+ int version;
+ struct ipc_namespace *ns;
+
+ if (semid < 0)
+ return -EINVAL;
+
+ version = ipc_parse_version(&cmd);
+ ns = current->nsproxy->ipc_ns;
+
+ switch(cmd) {
+ case IPC_INFO:
+ case SEM_INFO:
+ case IPC_STAT:
+ case SEM_STAT:
+ err = semctl_nolock(ns, semid, cmd, version, arg);
+ return err;
+ case GETALL:
+ case GETVAL:
+ case GETPID:
+ case GETNCNT:
+ case GETZCNT:
+ case SETVAL:
+ case SETALL:
+ err = semctl_main(ns,semid,semnum,cmd,version,arg);
+ return err;
+ case IPC_RMID:
+ case IPC_SET:
+ err = semctl_down(ns, semid, cmd, version, arg);
+ return err;
+ default:
+ return -EINVAL;
+ }
+}
+#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
+asmlinkage long SyS_semctl(int semid, int semnum, int cmd, union semun arg)
+{
+ return SYSC_semctl((int) semid, (int) semnum, (int) cmd, arg);
+}
+SYSCALL_ALIAS(sys_semctl, SyS_semctl);
+#endif
+
+/* If the task doesn't already have a undo_list, then allocate one
+ * here. We guarantee there is only one thread using this undo list,
+ * and current is THE ONE
+ *
+ * If this allocation and assignment succeeds, but later
+ * portions of this code fail, there is no need to free the sem_undo_list.
+ * Just let it stay associated with the task, and it'll be freed later
+ * at exit time.
+ *
+ * This can block, so callers must hold no locks.
+ */
+static inline int get_undo_list(struct sem_undo_list **undo_listp)
+{
+ struct sem_undo_list *undo_list;
+
+ undo_list = current->sysvsem.undo_list;
+ if (!undo_list) {
+ undo_list = kzalloc(sizeof(*undo_list), GFP_KERNEL);
+ if (undo_list == NULL)
+ return -ENOMEM;
+ spin_lock_init(&undo_list->lock);
+ atomic_set(&undo_list->refcnt, 1);
+ INIT_LIST_HEAD(&undo_list->list_proc);
+
+ current->sysvsem.undo_list = undo_list;
+ }
+ *undo_listp = undo_list;
+ return 0;
+}
+
+static struct sem_undo *__lookup_undo(struct sem_undo_list *ulp, int semid)
+{
+ struct sem_undo *un;
+
+ list_for_each_entry_rcu(un, &ulp->list_proc, list_proc) {
+ if (un->semid == semid)
+ return un;
+ }
+ return NULL;
+}
+
+static struct sem_undo *lookup_undo(struct sem_undo_list *ulp, int semid)
+{
+ struct sem_undo *un;
+
+ assert_spin_locked(&ulp->lock);
+
+ un = __lookup_undo(ulp, semid);
+ if (un) {
+ list_del_rcu(&un->list_proc);
+ list_add_rcu(&un->list_proc, &ulp->list_proc);
+ }
+ return un;
+}
+
+/**
+ * find_alloc_undo - Lookup (and if not present create) undo array
+ * @ns: namespace
+ * @semid: semaphore array id
+ *
+ * The function looks up (and if not present creates) the undo structure.
+ * The size of the undo structure depends on the size of the semaphore
+ * array, thus the alloc path is not that straightforward.
+ * Lifetime-rules: sem_undo is rcu-protected, on success, the function
+ * performs a rcu_read_lock().
+ */
+static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid)
+{
+ struct sem_array *sma;
+ struct sem_undo_list *ulp;
+ struct sem_undo *un, *new;
+ int nsems;
+ int error;
+
+ error = get_undo_list(&ulp);
+ if (error)
+ return ERR_PTR(error);
+
+ rcu_read_lock();
+ spin_lock(&ulp->lock);
+ un = lookup_undo(ulp, semid);
+ spin_unlock(&ulp->lock);
+ if (likely(un!=NULL))
+ goto out;
+ rcu_read_unlock();
+
+ /* no undo structure around - allocate one. */
+ /* step 1: figure out the size of the semaphore array */
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma))
+ return ERR_CAST(sma);
+
+ nsems = sma->sem_nsems;
+ sem_getref_and_unlock(sma);
+
+ /* step 2: allocate new undo structure */
+ new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL);
+ if (!new) {
+ sem_putref(sma);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* step 3: Acquire the lock on semaphore array */
+ sem_lock_and_putref(sma);
+ if (sma->sem_perm.deleted) {
+ sem_unlock(sma);
+ kfree(new);
+ un = ERR_PTR(-EIDRM);
+ goto out;
+ }
+ spin_lock(&ulp->lock);
+
+ /*
+ * step 4: check for races: did someone else allocate the undo struct?
+ */
+ un = lookup_undo(ulp, semid);
+ if (un) {
+ kfree(new);
+ goto success;
+ }
+ /* step 5: initialize & link new undo structure */
+ new->semadj = (short *) &new[1];
+ new->ulp = ulp;
+ new->semid = semid;
+ assert_spin_locked(&ulp->lock);
+ list_add_rcu(&new->list_proc, &ulp->list_proc);
+ assert_spin_locked(&sma->sem_perm.lock);
+ list_add(&new->list_id, &sma->list_id);
+ un = new;
+
+success:
+ spin_unlock(&ulp->lock);
+ rcu_read_lock();
+ sem_unlock(sma);
+out:
+ return un;
+}
+
+
+/**
+ * get_queue_result - Retrieve the result code from sem_queue
+ * @q: Pointer to queue structure
+ *
+ * Retrieve the return code from the pending queue. If IN_WAKEUP is found in
+ * q->status, then we must loop until the value is replaced with the final
+ * value: This may happen if a task is woken up by an unrelated event (e.g.
+ * signal) and in parallel the task is woken up by another task because it got
+ * the requested semaphores.
+ *
+ * The function can be called with or without holding the semaphore spinlock.
+ */
+static int get_queue_result(struct sem_queue *q)
+{
+ int error;
+
+ error = q->status;
+ while (unlikely(error == IN_WAKEUP)) {
+ cpu_relax();
+ error = q->status;
+ }
+
+ return error;
+}
+
+
+SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops,
+ unsigned, nsops, const struct timespec __user *, timeout)
+{
+ int error = -EINVAL;
+ struct sem_array *sma;
+ struct sembuf fast_sops[SEMOPM_FAST];
+ struct sembuf* sops = fast_sops, *sop;
+ struct sem_undo *un;
+ int undos = 0, alter = 0, max;
+ struct sem_queue queue;
+ unsigned long jiffies_left = 0;
+ struct ipc_namespace *ns;
+ struct list_head tasks;
+
+ ns = current->nsproxy->ipc_ns;
+
+ if (nsops < 1 || semid < 0)
+ return -EINVAL;
+ if (nsops > ns->sc_semopm)
+ return -E2BIG;
+ if(nsops > SEMOPM_FAST) {
+ sops = kmalloc(sizeof(*sops)*nsops,GFP_KERNEL);
+ if(sops==NULL)
+ return -ENOMEM;
+ }
+ if (copy_from_user (sops, tsops, nsops * sizeof(*tsops))) {
+ error=-EFAULT;
+ goto out_free;
+ }
+ if (timeout) {
+ struct timespec _timeout;
+ if (copy_from_user(&_timeout, timeout, sizeof(*timeout))) {
+ error = -EFAULT;
+ goto out_free;
+ }
+ if (_timeout.tv_sec < 0 || _timeout.tv_nsec < 0 ||
+ _timeout.tv_nsec >= 1000000000L) {
+ error = -EINVAL;
+ goto out_free;
+ }
+ jiffies_left = timespec_to_jiffies(&_timeout);
+ }
+ max = 0;
+ for (sop = sops; sop < sops + nsops; sop++) {
+ if (sop->sem_num >= max)
+ max = sop->sem_num;
+ if (sop->sem_flg & SEM_UNDO)
+ undos = 1;
+ if (sop->sem_op != 0)
+ alter = 1;
+ }
+
+ if (undos) {
+ un = find_alloc_undo(ns, semid);
+ if (IS_ERR(un)) {
+ error = PTR_ERR(un);
+ goto out_free;
+ }
+ } else
+ un = NULL;
+
+ INIT_LIST_HEAD(&tasks);
+
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma)) {
+ if (un)
+ rcu_read_unlock();
+ error = PTR_ERR(sma);
+ goto out_free;
+ }
+
+ /*
+ * semid identifiers are not unique - find_alloc_undo may have
+ * allocated an undo structure, it was invalidated by an RMID
+ * and now a new array with received the same id. Check and fail.
+ * This case can be detected checking un->semid. The existence of
+ * "un" itself is guaranteed by rcu.
+ */
+ error = -EIDRM;
+ if (un) {
+ if (un->semid == -1) {
+ rcu_read_unlock();
+ goto out_unlock_free;
+ } else {
+ /*
+ * rcu lock can be released, "un" cannot disappear:
+ * - sem_lock is acquired, thus IPC_RMID is
+ * impossible.
+ * - exit_sem is impossible, it always operates on
+ * current (or a dead task).
+ */
+
+ rcu_read_unlock();
+ }
+ }
+
+ error = -EFBIG;
+ if (max >= sma->sem_nsems)
+ goto out_unlock_free;
+
+ error = -EACCES;
+ if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO))
+ goto out_unlock_free;
+
+ error = security_sem_semop(sma, sops, nsops, alter);
+ if (error)
+ goto out_unlock_free;
+
+ error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current));
+ if (error <= 0) {
+ if (alter && error == 0)
+ do_smart_update(sma, sops, nsops, 1, &tasks);
+
+ goto out_unlock_free;
+ }
+
+ /* We need to sleep on this operation, so we put the current
+ * task into the pending queue and go to sleep.
+ */
+
+ queue.sops = sops;
+ queue.nsops = nsops;
+ queue.undo = un;
+ queue.pid = task_tgid_vnr(current);
+ queue.alter = alter;
+ if (alter)
+ list_add_tail(&queue.list, &sma->sem_pending);
+ else
+ list_add(&queue.list, &sma->sem_pending);
+
+ if (nsops == 1) {
+ struct sem *curr;
+ curr = &sma->sem_base[sops->sem_num];
+
+ if (alter)
+ list_add_tail(&queue.simple_list, &curr->sem_pending);
+ else
+ list_add(&queue.simple_list, &curr->sem_pending);
+ } else {
+ INIT_LIST_HEAD(&queue.simple_list);
+ sma->complex_count++;
+ }
+
+ queue.status = -EINTR;
+ queue.sleeper = current;
+
+sleep_again:
+ current->state = TASK_INTERRUPTIBLE;
+ sem_unlock(sma);
+
+ if (timeout)
+ jiffies_left = schedule_timeout(jiffies_left);
+ else
+ schedule();
+
+ error = get_queue_result(&queue);
+
+ if (error != -EINTR) {
+ /* fast path: update_queue already obtained all requested
+ * resources.
+ * Perform a smp_mb(): User space could assume that semop()
+ * is a memory barrier: Without the mb(), the cpu could
+ * speculatively read in user space stale data that was
+ * overwritten by the previous owner of the semaphore.
+ */
+ smp_mb();
+
+ goto out_free;
+ }
+
+ sma = sem_lock(ns, semid);
+
+ /*
+ * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing.
+ */
+ error = get_queue_result(&queue);
+
+ /*
+ * Array removed? If yes, leave without sem_unlock().
+ */
+ if (IS_ERR(sma)) {
+ goto out_free;
+ }
+
+
+ /*
+ * If queue.status != -EINTR we are woken up by another process.
+ * Leave without unlink_queue(), but with sem_unlock().
+ */
+
+ if (error != -EINTR) {
+ goto out_unlock_free;
+ }
+
+ /*
+ * If an interrupt occurred we have to clean up the queue
+ */
+ if (timeout && jiffies_left == 0)
+ error = -EAGAIN;
+
+ /*
+ * If the wakeup was spurious, just retry
+ */
+ if (error == -EINTR && !signal_pending(current))
+ goto sleep_again;
+
+ unlink_queue(sma, &queue);
+
+out_unlock_free:
+ sem_unlock(sma);
+
+ wake_up_sem_queue_do(&tasks);
+out_free:
+ if(sops != fast_sops)
+ kfree(sops);
+ return error;
+}
+
+SYSCALL_DEFINE3(semop, int, semid, struct sembuf __user *, tsops,
+ unsigned, nsops)
+{
+ return sys_semtimedop(semid, tsops, nsops, NULL);
+}
+
+/* If CLONE_SYSVSEM is set, establish sharing of SEM_UNDO state between
+ * parent and child tasks.
+ */
+
+int copy_semundo(unsigned long clone_flags, struct task_struct *tsk)
+{
+ struct sem_undo_list *undo_list;
+ int error;
+
+ if (clone_flags & CLONE_SYSVSEM) {
+ error = get_undo_list(&undo_list);
+ if (error)
+ return error;
+ atomic_inc(&undo_list->refcnt);
+ tsk->sysvsem.undo_list = undo_list;
+ } else
+ tsk->sysvsem.undo_list = NULL;
+
+ return 0;
+}
+
+/*
+ * add semadj values to semaphores, free undo structures.
+ * undo structures are not freed when semaphore arrays are destroyed
+ * so some of them may be out of date.
+ * IMPLEMENTATION NOTE: There is some confusion over whether the
+ * set of adjustments that needs to be done should be done in an atomic
+ * manner or not. That is, if we are attempting to decrement the semval
+ * should we queue up and wait until we can do so legally?
+ * The original implementation attempted to do this (queue and wait).
+ * The current implementation does not do so. The POSIX standard
+ * and SVID should be consulted to determine what behavior is mandated.
+ */
+void exit_sem(struct task_struct *tsk)
+{
+ struct sem_undo_list *ulp;
+
+ ulp = tsk->sysvsem.undo_list;
+ if (!ulp)
+ return;
+ tsk->sysvsem.undo_list = NULL;
+
+ if (!atomic_dec_and_test(&ulp->refcnt))
+ return;
+
+ for (;;) {
+ struct sem_array *sma;
+ struct sem_undo *un;
+ struct list_head tasks;
+ int semid;
+ int i;
+
+ rcu_read_lock();
+ un = list_entry_rcu(ulp->list_proc.next,
+ struct sem_undo, list_proc);
+ if (&un->list_proc == &ulp->list_proc)
+ semid = -1;
+ else
+ semid = un->semid;
+ rcu_read_unlock();
+
+ if (semid == -1)
+ break;
+
+ sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid);
+
+ /* exit_sem raced with IPC_RMID, nothing to do */
+ if (IS_ERR(sma))
+ continue;
+
+ un = __lookup_undo(ulp, semid);
+ if (un == NULL) {
+ /* exit_sem raced with IPC_RMID+semget() that created
+ * exactly the same semid. Nothing to do.
+ */
+ sem_unlock(sma);
+ continue;
+ }
+
+ /* remove un from the linked lists */
+ assert_spin_locked(&sma->sem_perm.lock);
+ list_del(&un->list_id);
+
+ spin_lock(&ulp->lock);
+ list_del_rcu(&un->list_proc);
+ spin_unlock(&ulp->lock);
+
+ /* perform adjustments registered in un */
+ for (i = 0; i < sma->sem_nsems; i++) {
+ struct sem * semaphore = &sma->sem_base[i];
+ if (un->semadj[i]) {
+ semaphore->semval += un->semadj[i];
+ /*
+ * Range checks of the new semaphore value,
+ * not defined by sus:
+ * - Some unices ignore the undo entirely
+ * (e.g. HP UX 11i 11.22, Tru64 V5.1)
+ * - some cap the value (e.g. FreeBSD caps
+ * at 0, but doesn't enforce SEMVMX)
+ *
+ * Linux caps the semaphore value, both at 0
+ * and at SEMVMX.
+ *
+ * Manfred <manfred@colorfullife.com>
+ */
+ if (semaphore->semval < 0)
+ semaphore->semval = 0;
+ if (semaphore->semval > SEMVMX)
+ semaphore->semval = SEMVMX;
+ semaphore->sempid = task_tgid_vnr(current);
+ }
+ }
+ /* maybe some queued-up processes were waiting for this */
+ INIT_LIST_HEAD(&tasks);
+ do_smart_update(sma, NULL, 0, 1, &tasks);
+ sem_unlock(sma);
+ wake_up_sem_queue_do(&tasks);
+
+ kfree_rcu(un, rcu);
+ }
+ kfree(ulp);
+}
+
+#ifdef CONFIG_PROC_FS
+static int sysvipc_sem_proc_show(struct seq_file *s, void *it)
+{
+ struct sem_array *sma = it;
+
+ return seq_printf(s,
+ "%10d %10d %4o %10u %5u %5u %5u %5u %10lu %10lu\n",
+ sma->sem_perm.key,
+ sma->sem_perm.id,
+ sma->sem_perm.mode,
+ sma->sem_nsems,
+ sma->sem_perm.uid,
+ sma->sem_perm.gid,
+ sma->sem_perm.cuid,
+ sma->sem_perm.cgid,
+ sma->sem_otime,
+ sma->sem_ctime);
+}
+#endif
diff --git a/ipc/shm.c b/ipc/shm.c
new file mode 100644
index 00000000..406c5b20
--- /dev/null
+++ b/ipc/shm.c
@@ -0,0 +1,1237 @@
+/*
+ * linux/ipc/shm.c
+ * Copyright (C) 1992, 1993 Krishna Balasubramanian
+ * Many improvements/fixes by Bruno Haible.
+ * Replaced `struct shm_desc' by `struct vm_area_struct', July 1994.
+ * Fixed the shm swap deallocation (shm_unuse()), August 1998 Andrea Arcangeli.
+ *
+ * /proc/sysvipc/shm support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
+ * BIGMEM support, Andrea Arcangeli <andrea@suse.de>
+ * SMP thread shm, Jean-Luc Boyard <jean-luc.boyard@siemens.fr>
+ * HIGHMEM support, Ingo Molnar <mingo@redhat.com>
+ * Make shmmax, shmall, shmmni sysctl'able, Christoph Rohland <cr@sap.com>
+ * Shared /dev/zero support, Kanoj Sarcar <kanoj@sgi.com>
+ * Move the mm functionality over to mm/shmem.c, Christoph Rohland <cr@sap.com>
+ *
+ * support for audit of ipc object properties and permission changes
+ * Dustin Kirkland <dustin.kirkland@us.ibm.com>
+ *
+ * namespaces support
+ * OpenVZ, SWsoft Inc.
+ * Pavel Emelianov <xemul@openvz.org>
+ */
+
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/shm.h>
+#include <linux/init.h>
+#include <linux/file.h>
+#include <linux/mman.h>
+#include <linux/shmem_fs.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/audit.h>
+#include <linux/capability.h>
+#include <linux/ptrace.h>
+#include <linux/seq_file.h>
+#include <linux/rwsem.h>
+#include <linux/nsproxy.h>
+#include <linux/mount.h>
+#include <linux/ipc_namespace.h>
+
+#include <asm/uaccess.h>
+
+#include "util.h"
+
+struct shm_file_data {
+ int id;
+ struct ipc_namespace *ns;
+ struct file *file;
+ const struct vm_operations_struct *vm_ops;
+};
+
+#define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data))
+
+static const struct file_operations shm_file_operations;
+static const struct vm_operations_struct shm_vm_ops;
+
+#define shm_ids(ns) ((ns)->ids[IPC_SHM_IDS])
+
+#define shm_unlock(shp) \
+ ipc_unlock(&(shp)->shm_perm)
+
+static int newseg(struct ipc_namespace *, struct ipc_params *);
+static void shm_open(struct vm_area_struct *vma);
+static void shm_close(struct vm_area_struct *vma);
+static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
+#ifdef CONFIG_PROC_FS
+static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
+#endif
+
+void shm_init_ns(struct ipc_namespace *ns)
+{
+ ns->shm_ctlmax = SHMMAX;
+ ns->shm_ctlall = SHMALL;
+ ns->shm_ctlmni = SHMMNI;
+ ns->shm_rmid_forced = 0;
+ ns->shm_tot = 0;
+ ipc_init_ids(&shm_ids(ns));
+}
+
+/*
+ * Called with shm_ids.rw_mutex (writer) and the shp structure locked.
+ * Only shm_ids.rw_mutex remains locked on exit.
+ */
+static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
+{
+ struct shmid_kernel *shp;
+ shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+
+ if (shp->shm_nattch){
+ shp->shm_perm.mode |= SHM_DEST;
+ /* Do not find it any more */
+ shp->shm_perm.key = IPC_PRIVATE;
+ shm_unlock(shp);
+ } else
+ shm_destroy(ns, shp);
+}
+
+#ifdef CONFIG_IPC_NS
+void shm_exit_ns(struct ipc_namespace *ns)
+{
+ free_ipcs(ns, &shm_ids(ns), do_shm_rmid);
+ idr_destroy(&ns->ids[IPC_SHM_IDS].ipcs_idr);
+}
+#endif
+
+static int __init ipc_ns_init(void)
+{
+ shm_init_ns(&init_ipc_ns);
+ return 0;
+}
+
+pure_initcall(ipc_ns_init);
+
+void __init shm_init (void)
+{
+ ipc_init_proc_interface("sysvipc/shm",
+#if BITS_PER_LONG <= 32
+ " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
+#else
+ " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
+#endif
+ IPC_SHM_IDS, sysvipc_shm_proc_show);
+}
+
+/*
+ * shm_lock_(check_) routines are called in the paths where the rw_mutex
+ * is not necessarily held.
+ */
+static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct shmid_kernel *)ipcp;
+
+ return container_of(ipcp, struct shmid_kernel, shm_perm);
+}
+
+static inline void shm_lock_by_ptr(struct shmid_kernel *ipcp)
+{
+ rcu_read_lock();
+ spin_lock(&ipcp->shm_perm.lock);
+}
+
+static inline struct shmid_kernel *shm_lock_check(struct ipc_namespace *ns,
+ int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_lock_check(&shm_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct shmid_kernel *)ipcp;
+
+ return container_of(ipcp, struct shmid_kernel, shm_perm);
+}
+
+static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
+{
+ ipc_rmid(&shm_ids(ns), &s->shm_perm);
+}
+
+
+/* This is called by fork, once for every shm attach. */
+static void shm_open(struct vm_area_struct *vma)
+{
+ struct file *file = vma->vm_file;
+ struct shm_file_data *sfd = shm_file_data(file);
+ struct shmid_kernel *shp;
+
+ shp = shm_lock(sfd->ns, sfd->id);
+ BUG_ON(IS_ERR(shp));
+ shp->shm_atim = get_seconds();
+ shp->shm_lprid = task_tgid_vnr(current);
+ shp->shm_nattch++;
+ shm_unlock(shp);
+}
+
+/*
+ * shm_destroy - free the struct shmid_kernel
+ *
+ * @ns: namespace
+ * @shp: struct to free
+ *
+ * It has to be called with shp and shm_ids.rw_mutex (writer) locked,
+ * but returns with shp unlocked and freed.
+ */
+static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
+{
+ ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ shm_rmid(ns, shp);
+ shm_unlock(shp);
+ if (!is_file_hugepages(shp->shm_file))
+ shmem_lock(shp->shm_file, 0, shp->mlock_user);
+ else if (shp->mlock_user)
+ user_shm_unlock(shp->shm_file->f_path.dentry->d_inode->i_size,
+ shp->mlock_user);
+ fput (shp->shm_file);
+ security_shm_free(shp);
+ ipc_rcu_putref(shp);
+}
+
+/*
+ * shm_may_destroy - identifies whether shm segment should be destroyed now
+ *
+ * Returns true if and only if there are no active users of the segment and
+ * one of the following is true:
+ *
+ * 1) shmctl(id, IPC_RMID, NULL) was called for this shp
+ *
+ * 2) sysctl kernel.shm_rmid_forced is set to 1.
+ */
+static bool shm_may_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
+{
+ return (shp->shm_nattch == 0) &&
+ (ns->shm_rmid_forced ||
+ (shp->shm_perm.mode & SHM_DEST));
+}
+
+/*
+ * remove the attach descriptor vma.
+ * free memory for segment if it is marked destroyed.
+ * The descriptor has already been removed from the current->mm->mmap list
+ * and will later be kfree()d.
+ */
+static void shm_close(struct vm_area_struct *vma)
+{
+ struct file * file = vma->vm_file;
+ struct shm_file_data *sfd = shm_file_data(file);
+ struct shmid_kernel *shp;
+ struct ipc_namespace *ns = sfd->ns;
+
+ down_write(&shm_ids(ns).rw_mutex);
+ /* remove from the list of attaches of the shm segment */
+ shp = shm_lock(ns, sfd->id);
+ BUG_ON(IS_ERR(shp));
+ shp->shm_lprid = task_tgid_vnr(current);
+ shp->shm_dtim = get_seconds();
+ shp->shm_nattch--;
+ if (shm_may_destroy(ns, shp))
+ shm_destroy(ns, shp);
+ else
+ shm_unlock(shp);
+ up_write(&shm_ids(ns).rw_mutex);
+}
+
+/* Called with ns->shm_ids(ns).rw_mutex locked */
+static int shm_try_destroy_current(int id, void *p, void *data)
+{
+ struct ipc_namespace *ns = data;
+ struct kern_ipc_perm *ipcp = p;
+ struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+
+ if (shp->shm_creator != current)
+ return 0;
+
+ /*
+ * Mark it as orphaned to destroy the segment when
+ * kernel.shm_rmid_forced is changed.
+ * It is noop if the following shm_may_destroy() returns true.
+ */
+ shp->shm_creator = NULL;
+
+ /*
+ * Don't even try to destroy it. If shm_rmid_forced=0 and IPC_RMID
+ * is not set, it shouldn't be deleted here.
+ */
+ if (!ns->shm_rmid_forced)
+ return 0;
+
+ if (shm_may_destroy(ns, shp)) {
+ shm_lock_by_ptr(shp);
+ shm_destroy(ns, shp);
+ }
+ return 0;
+}
+
+/* Called with ns->shm_ids(ns).rw_mutex locked */
+static int shm_try_destroy_orphaned(int id, void *p, void *data)
+{
+ struct ipc_namespace *ns = data;
+ struct kern_ipc_perm *ipcp = p;
+ struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+
+ /*
+ * We want to destroy segments without users and with already
+ * exit'ed originating process.
+ *
+ * As shp->* are changed under rw_mutex, it's safe to skip shp locking.
+ */
+ if (shp->shm_creator != NULL)
+ return 0;
+
+ if (shm_may_destroy(ns, shp)) {
+ shm_lock_by_ptr(shp);
+ shm_destroy(ns, shp);
+ }
+ return 0;
+}
+
+void shm_destroy_orphaned(struct ipc_namespace *ns)
+{
+ down_write(&shm_ids(ns).rw_mutex);
+ if (shm_ids(ns).in_use)
+ idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_orphaned, ns);
+ up_write(&shm_ids(ns).rw_mutex);
+}
+
+
+void exit_shm(struct task_struct *task)
+{
+ struct ipc_namespace *ns = task->nsproxy->ipc_ns;
+
+ if (shm_ids(ns).in_use == 0)
+ return;
+
+ /* Destroy all already created segments, but not mapped yet */
+ down_write(&shm_ids(ns).rw_mutex);
+ if (shm_ids(ns).in_use)
+ idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_current, ns);
+ up_write(&shm_ids(ns).rw_mutex);
+}
+
+static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct file *file = vma->vm_file;
+ struct shm_file_data *sfd = shm_file_data(file);
+
+ return sfd->vm_ops->fault(vma, vmf);
+}
+
+#ifdef CONFIG_NUMA
+static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
+{
+ struct file *file = vma->vm_file;
+ struct shm_file_data *sfd = shm_file_data(file);
+ int err = 0;
+ if (sfd->vm_ops->set_policy)
+ err = sfd->vm_ops->set_policy(vma, new);
+ return err;
+}
+
+static struct mempolicy *shm_get_policy(struct vm_area_struct *vma,
+ unsigned long addr)
+{
+ struct file *file = vma->vm_file;
+ struct shm_file_data *sfd = shm_file_data(file);
+ struct mempolicy *pol = NULL;
+
+ if (sfd->vm_ops->get_policy)
+ pol = sfd->vm_ops->get_policy(vma, addr);
+ else if (vma->vm_policy)
+ pol = vma->vm_policy;
+
+ return pol;
+}
+#endif
+
+static int shm_mmap(struct file * file, struct vm_area_struct * vma)
+{
+ struct shm_file_data *sfd = shm_file_data(file);
+ int ret;
+
+ ret = sfd->file->f_op->mmap(sfd->file, vma);
+ if (ret != 0)
+ return ret;
+ sfd->vm_ops = vma->vm_ops;
+#ifdef CONFIG_MMU
+ BUG_ON(!sfd->vm_ops->fault);
+#endif
+ vma->vm_ops = &shm_vm_ops;
+ shm_open(vma);
+
+ return ret;
+}
+
+static int shm_release(struct inode *ino, struct file *file)
+{
+ struct shm_file_data *sfd = shm_file_data(file);
+
+ put_ipc_ns(sfd->ns);
+ shm_file_data(file) = NULL;
+ kfree(sfd);
+ return 0;
+}
+
+static int shm_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+ struct shm_file_data *sfd = shm_file_data(file);
+
+ if (!sfd->file->f_op->fsync)
+ return -EINVAL;
+ return sfd->file->f_op->fsync(sfd->file, start, end, datasync);
+}
+
+static unsigned long shm_get_unmapped_area(struct file *file,
+ unsigned long addr, unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ struct shm_file_data *sfd = shm_file_data(file);
+ return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len,
+ pgoff, flags);
+}
+
+static const struct file_operations shm_file_operations = {
+ .mmap = shm_mmap,
+ .fsync = shm_fsync,
+ .release = shm_release,
+#ifndef CONFIG_MMU
+ .get_unmapped_area = shm_get_unmapped_area,
+#endif
+ .llseek = noop_llseek,
+};
+
+static const struct file_operations shm_file_operations_huge = {
+ .mmap = shm_mmap,
+ .fsync = shm_fsync,
+ .release = shm_release,
+ .get_unmapped_area = shm_get_unmapped_area,
+ .llseek = noop_llseek,
+};
+
+int is_file_shm_hugepages(struct file *file)
+{
+ return file->f_op == &shm_file_operations_huge;
+}
+
+static const struct vm_operations_struct shm_vm_ops = {
+ .open = shm_open, /* callback for a new vm-area open */
+ .close = shm_close, /* callback for when the vm-area is released */
+ .fault = shm_fault,
+#if defined(CONFIG_NUMA)
+ .set_policy = shm_set_policy,
+ .get_policy = shm_get_policy,
+#endif
+};
+
+/**
+ * newseg - Create a new shared memory segment
+ * @ns: namespace
+ * @params: ptr to the structure that contains key, size and shmflg
+ *
+ * Called with shm_ids.rw_mutex held as a writer.
+ */
+
+static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
+{
+ key_t key = params->key;
+ int shmflg = params->flg;
+ size_t size = params->u.size;
+ int error;
+ struct shmid_kernel *shp;
+ int numpages = (size + PAGE_SIZE -1) >> PAGE_SHIFT;
+ struct file * file;
+ char name[13];
+ int id;
+ vm_flags_t acctflag = 0;
+
+ if (size < SHMMIN || size > ns->shm_ctlmax)
+ return -EINVAL;
+
+ if (ns->shm_tot + numpages > ns->shm_ctlall)
+ return -ENOSPC;
+
+ shp = ipc_rcu_alloc(sizeof(*shp));
+ if (!shp)
+ return -ENOMEM;
+
+ shp->shm_perm.key = key;
+ shp->shm_perm.mode = (shmflg & S_IRWXUGO);
+ shp->mlock_user = NULL;
+
+ shp->shm_perm.security = NULL;
+ error = security_shm_alloc(shp);
+ if (error) {
+ ipc_rcu_putref(shp);
+ return error;
+ }
+
+ sprintf (name, "SYSV%08x", key);
+ if (shmflg & SHM_HUGETLB) {
+ /* hugetlb_file_setup applies strict accounting */
+ if (shmflg & SHM_NORESERVE)
+ acctflag = VM_NORESERVE;
+ file = hugetlb_file_setup(name, 0, size, acctflag,
+ &shp->mlock_user, HUGETLB_SHMFS_INODE);
+ } else {
+ /*
+ * Do not allow no accounting for OVERCOMMIT_NEVER, even
+ * if it's asked for.
+ */
+ if ((shmflg & SHM_NORESERVE) &&
+ sysctl_overcommit_memory != OVERCOMMIT_NEVER)
+ acctflag = VM_NORESERVE;
+ file = shmem_file_setup(name, size, acctflag);
+ }
+ error = PTR_ERR(file);
+ if (IS_ERR(file))
+ goto no_file;
+
+ id = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni);
+ if (id < 0) {
+ error = id;
+ goto no_id;
+ }
+
+ shp->shm_cprid = task_tgid_vnr(current);
+ shp->shm_lprid = 0;
+ shp->shm_atim = shp->shm_dtim = 0;
+ shp->shm_ctim = get_seconds();
+ shp->shm_segsz = size;
+ shp->shm_nattch = 0;
+ shp->shm_file = file;
+ shp->shm_creator = current;
+ /*
+ * shmid gets reported as "inode#" in /proc/pid/maps.
+ * proc-ps tools use this. Changing this will break them.
+ */
+ file->f_dentry->d_inode->i_ino = shp->shm_perm.id;
+
+ ns->shm_tot += numpages;
+ error = shp->shm_perm.id;
+ shm_unlock(shp);
+ return error;
+
+no_id:
+ if (is_file_hugepages(file) && shp->mlock_user)
+ user_shm_unlock(size, shp->mlock_user);
+ fput(file);
+no_file:
+ security_shm_free(shp);
+ ipc_rcu_putref(shp);
+ return error;
+}
+
+/*
+ * Called with shm_ids.rw_mutex and ipcp locked.
+ */
+static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
+{
+ struct shmid_kernel *shp;
+
+ shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+ return security_shm_associate(shp, shmflg);
+}
+
+/*
+ * Called with shm_ids.rw_mutex and ipcp locked.
+ */
+static inline int shm_more_checks(struct kern_ipc_perm *ipcp,
+ struct ipc_params *params)
+{
+ struct shmid_kernel *shp;
+
+ shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+ if (shp->shm_segsz < params->u.size)
+ return -EINVAL;
+
+ return 0;
+}
+
+SYSCALL_DEFINE3(shmget, key_t, key, size_t, size, int, shmflg)
+{
+ struct ipc_namespace *ns;
+ struct ipc_ops shm_ops;
+ struct ipc_params shm_params;
+
+ ns = current->nsproxy->ipc_ns;
+
+ shm_ops.getnew = newseg;
+ shm_ops.associate = shm_security;
+ shm_ops.more_checks = shm_more_checks;
+
+ shm_params.key = key;
+ shm_params.flg = shmflg;
+ shm_params.u.size = size;
+
+ return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params);
+}
+
+static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version)
+{
+ switch(version) {
+ case IPC_64:
+ return copy_to_user(buf, in, sizeof(*in));
+ case IPC_OLD:
+ {
+ struct shmid_ds out;
+
+ memset(&out, 0, sizeof(out));
+ ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm);
+ out.shm_segsz = in->shm_segsz;
+ out.shm_atime = in->shm_atime;
+ out.shm_dtime = in->shm_dtime;
+ out.shm_ctime = in->shm_ctime;
+ out.shm_cpid = in->shm_cpid;
+ out.shm_lpid = in->shm_lpid;
+ out.shm_nattch = in->shm_nattch;
+
+ return copy_to_user(buf, &out, sizeof(out));
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static inline unsigned long
+copy_shmid_from_user(struct shmid64_ds *out, void __user *buf, int version)
+{
+ switch(version) {
+ case IPC_64:
+ if (copy_from_user(out, buf, sizeof(*out)))
+ return -EFAULT;
+ return 0;
+ case IPC_OLD:
+ {
+ struct shmid_ds tbuf_old;
+
+ if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
+ return -EFAULT;
+
+ out->shm_perm.uid = tbuf_old.shm_perm.uid;
+ out->shm_perm.gid = tbuf_old.shm_perm.gid;
+ out->shm_perm.mode = tbuf_old.shm_perm.mode;
+
+ return 0;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version)
+{
+ switch(version) {
+ case IPC_64:
+ return copy_to_user(buf, in, sizeof(*in));
+ case IPC_OLD:
+ {
+ struct shminfo out;
+
+ if(in->shmmax > INT_MAX)
+ out.shmmax = INT_MAX;
+ else
+ out.shmmax = (int)in->shmmax;
+
+ out.shmmin = in->shmmin;
+ out.shmmni = in->shmmni;
+ out.shmseg = in->shmseg;
+ out.shmall = in->shmall;
+
+ return copy_to_user(buf, &out, sizeof(out));
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+/*
+ * Calculate and add used RSS and swap pages of a shm.
+ * Called with shm_ids.rw_mutex held as a reader
+ */
+static void shm_add_rss_swap(struct shmid_kernel *shp,
+ unsigned long *rss_add, unsigned long *swp_add)
+{
+ struct inode *inode;
+
+ inode = shp->shm_file->f_path.dentry->d_inode;
+
+ if (is_file_hugepages(shp->shm_file)) {
+ struct address_space *mapping = inode->i_mapping;
+ struct hstate *h = hstate_file(shp->shm_file);
+ *rss_add += pages_per_huge_page(h) * mapping->nrpages;
+ } else {
+#ifdef CONFIG_SHMEM
+ struct shmem_inode_info *info = SHMEM_I(inode);
+ spin_lock(&info->lock);
+ *rss_add += inode->i_mapping->nrpages;
+ *swp_add += info->swapped;
+ spin_unlock(&info->lock);
+#else
+ *rss_add += inode->i_mapping->nrpages;
+#endif
+ }
+}
+
+/*
+ * Called with shm_ids.rw_mutex held as a reader
+ */
+static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
+ unsigned long *swp)
+{
+ int next_id;
+ int total, in_use;
+
+ *rss = 0;
+ *swp = 0;
+
+ in_use = shm_ids(ns).in_use;
+
+ for (total = 0, next_id = 0; total < in_use; next_id++) {
+ struct kern_ipc_perm *ipc;
+ struct shmid_kernel *shp;
+
+ ipc = idr_find(&shm_ids(ns).ipcs_idr, next_id);
+ if (ipc == NULL)
+ continue;
+ shp = container_of(ipc, struct shmid_kernel, shm_perm);
+
+ shm_add_rss_swap(shp, rss, swp);
+
+ total++;
+ }
+}
+
+/*
+ * This function handles some shmctl commands which require the rw_mutex
+ * to be held in write mode.
+ * NOTE: no locks must be held, the rw_mutex is taken inside this function.
+ */
+static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
+ struct shmid_ds __user *buf, int version)
+{
+ struct kern_ipc_perm *ipcp;
+ struct shmid64_ds shmid64;
+ struct shmid_kernel *shp;
+ int err;
+
+ if (cmd == IPC_SET) {
+ if (copy_shmid_from_user(&shmid64, buf, version))
+ return -EFAULT;
+ }
+
+ ipcp = ipcctl_pre_down(ns, &shm_ids(ns), shmid, cmd,
+ &shmid64.shm_perm, 0);
+ if (IS_ERR(ipcp))
+ return PTR_ERR(ipcp);
+
+ shp = container_of(ipcp, struct shmid_kernel, shm_perm);
+
+ err = security_shm_shmctl(shp, cmd);
+ if (err)
+ goto out_unlock;
+ switch (cmd) {
+ case IPC_RMID:
+ do_shm_rmid(ns, ipcp);
+ goto out_up;
+ case IPC_SET:
+ ipc_update_perm(&shmid64.shm_perm, ipcp);
+ shp->shm_ctim = get_seconds();
+ break;
+ default:
+ err = -EINVAL;
+ }
+out_unlock:
+ shm_unlock(shp);
+out_up:
+ up_write(&shm_ids(ns).rw_mutex);
+ return err;
+}
+
+SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
+{
+ struct shmid_kernel *shp;
+ int err, version;
+ struct ipc_namespace *ns;
+
+ if (cmd < 0 || shmid < 0) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ version = ipc_parse_version(&cmd);
+ ns = current->nsproxy->ipc_ns;
+
+ switch (cmd) { /* replace with proc interface ? */
+ case IPC_INFO:
+ {
+ struct shminfo64 shminfo;
+
+ err = security_shm_shmctl(NULL, cmd);
+ if (err)
+ return err;
+
+ memset(&shminfo, 0, sizeof(shminfo));
+ shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni;
+ shminfo.shmmax = ns->shm_ctlmax;
+ shminfo.shmall = ns->shm_ctlall;
+
+ shminfo.shmmin = SHMMIN;
+ if(copy_shminfo_to_user (buf, &shminfo, version))
+ return -EFAULT;
+
+ down_read(&shm_ids(ns).rw_mutex);
+ err = ipc_get_maxid(&shm_ids(ns));
+ up_read(&shm_ids(ns).rw_mutex);
+
+ if(err<0)
+ err = 0;
+ goto out;
+ }
+ case SHM_INFO:
+ {
+ struct shm_info shm_info;
+
+ err = security_shm_shmctl(NULL, cmd);
+ if (err)
+ return err;
+
+ memset(&shm_info, 0, sizeof(shm_info));
+ down_read(&shm_ids(ns).rw_mutex);
+ shm_info.used_ids = shm_ids(ns).in_use;
+ shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp);
+ shm_info.shm_tot = ns->shm_tot;
+ shm_info.swap_attempts = 0;
+ shm_info.swap_successes = 0;
+ err = ipc_get_maxid(&shm_ids(ns));
+ up_read(&shm_ids(ns).rw_mutex);
+ if (copy_to_user(buf, &shm_info, sizeof(shm_info))) {
+ err = -EFAULT;
+ goto out;
+ }
+
+ err = err < 0 ? 0 : err;
+ goto out;
+ }
+ case SHM_STAT:
+ case IPC_STAT:
+ {
+ struct shmid64_ds tbuf;
+ int result;
+
+ if (cmd == SHM_STAT) {
+ shp = shm_lock(ns, shmid);
+ if (IS_ERR(shp)) {
+ err = PTR_ERR(shp);
+ goto out;
+ }
+ result = shp->shm_perm.id;
+ } else {
+ shp = shm_lock_check(ns, shmid);
+ if (IS_ERR(shp)) {
+ err = PTR_ERR(shp);
+ goto out;
+ }
+ result = 0;
+ }
+ err = -EACCES;
+ if (ipcperms(ns, &shp->shm_perm, S_IRUGO))
+ goto out_unlock;
+ err = security_shm_shmctl(shp, cmd);
+ if (err)
+ goto out_unlock;
+ memset(&tbuf, 0, sizeof(tbuf));
+ kernel_to_ipc64_perm(&shp->shm_perm, &tbuf.shm_perm);
+ tbuf.shm_segsz = shp->shm_segsz;
+ tbuf.shm_atime = shp->shm_atim;
+ tbuf.shm_dtime = shp->shm_dtim;
+ tbuf.shm_ctime = shp->shm_ctim;
+ tbuf.shm_cpid = shp->shm_cprid;
+ tbuf.shm_lpid = shp->shm_lprid;
+ tbuf.shm_nattch = shp->shm_nattch;
+ shm_unlock(shp);
+ if(copy_shmid_to_user (buf, &tbuf, version))
+ err = -EFAULT;
+ else
+ err = result;
+ goto out;
+ }
+ case SHM_LOCK:
+ case SHM_UNLOCK:
+ {
+ struct file *shm_file;
+
+ shp = shm_lock_check(ns, shmid);
+ if (IS_ERR(shp)) {
+ err = PTR_ERR(shp);
+ goto out;
+ }
+
+ audit_ipc_obj(&(shp->shm_perm));
+
+ if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) {
+ uid_t euid = current_euid();
+ err = -EPERM;
+ if (euid != shp->shm_perm.uid &&
+ euid != shp->shm_perm.cuid)
+ goto out_unlock;
+ if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK))
+ goto out_unlock;
+ }
+
+ err = security_shm_shmctl(shp, cmd);
+ if (err)
+ goto out_unlock;
+
+ shm_file = shp->shm_file;
+ if (is_file_hugepages(shm_file))
+ goto out_unlock;
+
+ if (cmd == SHM_LOCK) {
+ struct user_struct *user = current_user();
+ err = shmem_lock(shm_file, 1, user);
+ if (!err && !(shp->shm_perm.mode & SHM_LOCKED)) {
+ shp->shm_perm.mode |= SHM_LOCKED;
+ shp->mlock_user = user;
+ }
+ goto out_unlock;
+ }
+
+ /* SHM_UNLOCK */
+ if (!(shp->shm_perm.mode & SHM_LOCKED))
+ goto out_unlock;
+ shmem_lock(shm_file, 0, shp->mlock_user);
+ shp->shm_perm.mode &= ~SHM_LOCKED;
+ shp->mlock_user = NULL;
+ get_file(shm_file);
+ shm_unlock(shp);
+ shmem_unlock_mapping(shm_file->f_mapping);
+ fput(shm_file);
+ goto out;
+ }
+ case IPC_RMID:
+ case IPC_SET:
+ err = shmctl_down(ns, shmid, cmd, buf, version);
+ return err;
+ default:
+ return -EINVAL;
+ }
+
+out_unlock:
+ shm_unlock(shp);
+out:
+ return err;
+}
+
+/*
+ * Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists.
+ *
+ * NOTE! Despite the name, this is NOT a direct system call entrypoint. The
+ * "raddr" thing points to kernel space, and there has to be a wrapper around
+ * this.
+ */
+long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
+{
+ struct shmid_kernel *shp;
+ unsigned long addr;
+ unsigned long size;
+ struct file * file;
+ int err;
+ unsigned long flags;
+ unsigned long prot;
+ int acc_mode;
+ unsigned long user_addr;
+ struct ipc_namespace *ns;
+ struct shm_file_data *sfd;
+ struct path path;
+ fmode_t f_mode;
+
+ err = -EINVAL;
+ if (shmid < 0)
+ goto out;
+ else if ((addr = (ulong)shmaddr)) {
+ if (addr & (SHMLBA-1)) {
+ if (shmflg & SHM_RND)
+ addr &= ~(SHMLBA-1); /* round down */
+ else
+#ifndef __ARCH_FORCE_SHMLBA
+ if (addr & ~PAGE_MASK)
+#endif
+ goto out;
+ }
+ flags = MAP_SHARED | MAP_FIXED;
+ } else {
+ if ((shmflg & SHM_REMAP))
+ goto out;
+
+ flags = MAP_SHARED;
+ }
+
+ if (shmflg & SHM_RDONLY) {
+ prot = PROT_READ;
+ acc_mode = S_IRUGO;
+ f_mode = FMODE_READ;
+ } else {
+ prot = PROT_READ | PROT_WRITE;
+ acc_mode = S_IRUGO | S_IWUGO;
+ f_mode = FMODE_READ | FMODE_WRITE;
+ }
+ if (shmflg & SHM_EXEC) {
+ prot |= PROT_EXEC;
+ acc_mode |= S_IXUGO;
+ }
+
+ /*
+ * We cannot rely on the fs check since SYSV IPC does have an
+ * additional creator id...
+ */
+ ns = current->nsproxy->ipc_ns;
+ shp = shm_lock_check(ns, shmid);
+ if (IS_ERR(shp)) {
+ err = PTR_ERR(shp);
+ goto out;
+ }
+
+ err = -EACCES;
+ if (ipcperms(ns, &shp->shm_perm, acc_mode))
+ goto out_unlock;
+
+ err = security_shm_shmat(shp, shmaddr, shmflg);
+ if (err)
+ goto out_unlock;
+
+ path = shp->shm_file->f_path;
+ path_get(&path);
+ shp->shm_nattch++;
+ size = i_size_read(path.dentry->d_inode);
+ shm_unlock(shp);
+
+ err = -ENOMEM;
+ sfd = kzalloc(sizeof(*sfd), GFP_KERNEL);
+ if (!sfd)
+ goto out_put_dentry;
+
+ file = alloc_file(&path, f_mode,
+ is_file_hugepages(shp->shm_file) ?
+ &shm_file_operations_huge :
+ &shm_file_operations);
+ if (!file)
+ goto out_free;
+
+ file->private_data = sfd;
+ file->f_mapping = shp->shm_file->f_mapping;
+ sfd->id = shp->shm_perm.id;
+ sfd->ns = get_ipc_ns(ns);
+ sfd->file = shp->shm_file;
+ sfd->vm_ops = NULL;
+
+ down_write(&current->mm->mmap_sem);
+ if (addr && !(shmflg & SHM_REMAP)) {
+ err = -EINVAL;
+ if (find_vma_intersection(current->mm, addr, addr + size))
+ goto invalid;
+ /*
+ * If shm segment goes below stack, make sure there is some
+ * space left for the stack to grow (at least 4 pages).
+ */
+ if (addr < current->mm->start_stack &&
+ addr > current->mm->start_stack - size - PAGE_SIZE * 5)
+ goto invalid;
+ }
+
+ user_addr = do_mmap (file, addr, size, prot, flags, 0);
+ *raddr = user_addr;
+ err = 0;
+ if (IS_ERR_VALUE(user_addr))
+ err = (long)user_addr;
+invalid:
+ up_write(&current->mm->mmap_sem);
+
+ fput(file);
+
+out_nattch:
+ down_write(&shm_ids(ns).rw_mutex);
+ shp = shm_lock(ns, shmid);
+ BUG_ON(IS_ERR(shp));
+ shp->shm_nattch--;
+ if (shm_may_destroy(ns, shp))
+ shm_destroy(ns, shp);
+ else
+ shm_unlock(shp);
+ up_write(&shm_ids(ns).rw_mutex);
+
+out:
+ return err;
+
+out_unlock:
+ shm_unlock(shp);
+ goto out;
+
+out_free:
+ kfree(sfd);
+out_put_dentry:
+ path_put(&path);
+ goto out_nattch;
+}
+
+SYSCALL_DEFINE3(shmat, int, shmid, char __user *, shmaddr, int, shmflg)
+{
+ unsigned long ret;
+ long err;
+
+ err = do_shmat(shmid, shmaddr, shmflg, &ret);
+ if (err)
+ return err;
+ force_successful_syscall_return();
+ return (long)ret;
+}
+
+/*
+ * detach and kill segment if marked destroyed.
+ * The work is done in shm_close.
+ */
+SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ unsigned long addr = (unsigned long)shmaddr;
+ int retval = -EINVAL;
+#ifdef CONFIG_MMU
+ loff_t size = 0;
+ struct vm_area_struct *next;
+#endif
+
+ if (addr & ~PAGE_MASK)
+ return retval;
+
+ down_write(&mm->mmap_sem);
+
+ /*
+ * This function tries to be smart and unmap shm segments that
+ * were modified by partial mlock or munmap calls:
+ * - It first determines the size of the shm segment that should be
+ * unmapped: It searches for a vma that is backed by shm and that
+ * started at address shmaddr. It records it's size and then unmaps
+ * it.
+ * - Then it unmaps all shm vmas that started at shmaddr and that
+ * are within the initially determined size.
+ * Errors from do_munmap are ignored: the function only fails if
+ * it's called with invalid parameters or if it's called to unmap
+ * a part of a vma. Both calls in this function are for full vmas,
+ * the parameters are directly copied from the vma itself and always
+ * valid - therefore do_munmap cannot fail. (famous last words?)
+ */
+ /*
+ * If it had been mremap()'d, the starting address would not
+ * match the usual checks anyway. So assume all vma's are
+ * above the starting address given.
+ */
+ vma = find_vma(mm, addr);
+
+#ifdef CONFIG_MMU
+ while (vma) {
+ next = vma->vm_next;
+
+ /*
+ * Check if the starting address would match, i.e. it's
+ * a fragment created by mprotect() and/or munmap(), or it
+ * otherwise it starts at this address with no hassles.
+ */
+ if ((vma->vm_ops == &shm_vm_ops) &&
+ (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) {
+
+
+ size = vma->vm_file->f_path.dentry->d_inode->i_size;
+ do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
+ /*
+ * We discovered the size of the shm segment, so
+ * break out of here and fall through to the next
+ * loop that uses the size information to stop
+ * searching for matching vma's.
+ */
+ retval = 0;
+ vma = next;
+ break;
+ }
+ vma = next;
+ }
+
+ /*
+ * We need look no further than the maximum address a fragment
+ * could possibly have landed at. Also cast things to loff_t to
+ * prevent overflows and make comparisons vs. equal-width types.
+ */
+ size = PAGE_ALIGN(size);
+ while (vma && (loff_t)(vma->vm_end - addr) <= size) {
+ next = vma->vm_next;
+
+ /* finding a matching vma now does not alter retval */
+ if ((vma->vm_ops == &shm_vm_ops) &&
+ (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff)
+
+ do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
+ vma = next;
+ }
+
+#else /* CONFIG_MMU */
+ /* under NOMMU conditions, the exact address to be destroyed must be
+ * given */
+ retval = -EINVAL;
+ if (vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) {
+ do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
+ retval = 0;
+ }
+
+#endif
+
+ up_write(&mm->mmap_sem);
+ return retval;
+}
+
+#ifdef CONFIG_PROC_FS
+static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
+{
+ struct shmid_kernel *shp = it;
+ unsigned long rss = 0, swp = 0;
+
+ shm_add_rss_swap(shp, &rss, &swp);
+
+#if BITS_PER_LONG <= 32
+#define SIZE_SPEC "%10lu"
+#else
+#define SIZE_SPEC "%21lu"
+#endif
+
+ return seq_printf(s,
+ "%10d %10d %4o " SIZE_SPEC " %5u %5u "
+ "%5lu %5u %5u %5u %5u %10lu %10lu %10lu "
+ SIZE_SPEC " " SIZE_SPEC "\n",
+ shp->shm_perm.key,
+ shp->shm_perm.id,
+ shp->shm_perm.mode,
+ shp->shm_segsz,
+ shp->shm_cprid,
+ shp->shm_lprid,
+ shp->shm_nattch,
+ shp->shm_perm.uid,
+ shp->shm_perm.gid,
+ shp->shm_perm.cuid,
+ shp->shm_perm.cgid,
+ shp->shm_atim,
+ shp->shm_dtim,
+ shp->shm_ctim,
+ rss * PAGE_SIZE,
+ swp * PAGE_SIZE);
+}
+#endif
diff --git a/ipc/syscall.c b/ipc/syscall.c
new file mode 100644
index 00000000..1d6f53f6
--- /dev/null
+++ b/ipc/syscall.c
@@ -0,0 +1,99 @@
+/*
+ * sys_ipc() is the old de-multiplexer for the SysV IPC calls.
+ *
+ * This is really horribly ugly, and new architectures should just wire up
+ * the individual syscalls instead.
+ */
+#include <linux/unistd.h>
+
+#ifdef __ARCH_WANT_SYS_IPC
+#include <linux/errno.h>
+#include <linux/ipc.h>
+#include <linux/shm.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+
+SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
+ unsigned long, third, void __user *, ptr, long, fifth)
+{
+ int version, ret;
+
+ version = call >> 16; /* hack for backward compatibility */
+ call &= 0xffff;
+
+ switch (call) {
+ case SEMOP:
+ return sys_semtimedop(first, (struct sembuf __user *)ptr,
+ second, NULL);
+ case SEMTIMEDOP:
+ return sys_semtimedop(first, (struct sembuf __user *)ptr,
+ second,
+ (const struct timespec __user *)fifth);
+
+ case SEMGET:
+ return sys_semget(first, second, third);
+ case SEMCTL: {
+ union semun fourth;
+ if (!ptr)
+ return -EINVAL;
+ if (get_user(fourth.__pad, (void __user * __user *) ptr))
+ return -EFAULT;
+ return sys_semctl(first, second, third, fourth);
+ }
+
+ case MSGSND:
+ return sys_msgsnd(first, (struct msgbuf __user *) ptr,
+ second, third);
+ case MSGRCV:
+ switch (version) {
+ case 0: {
+ struct ipc_kludge tmp;
+ if (!ptr)
+ return -EINVAL;
+
+ if (copy_from_user(&tmp,
+ (struct ipc_kludge __user *) ptr,
+ sizeof(tmp)))
+ return -EFAULT;
+ return sys_msgrcv(first, tmp.msgp, second,
+ tmp.msgtyp, third);
+ }
+ default:
+ return sys_msgrcv(first,
+ (struct msgbuf __user *) ptr,
+ second, fifth, third);
+ }
+ case MSGGET:
+ return sys_msgget((key_t) first, second);
+ case MSGCTL:
+ return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);
+
+ case SHMAT:
+ switch (version) {
+ default: {
+ unsigned long raddr;
+ ret = do_shmat(first, (char __user *)ptr,
+ second, &raddr);
+ if (ret)
+ return ret;
+ return put_user(raddr, (unsigned long __user *) third);
+ }
+ case 1:
+ /*
+ * This was the entry point for kernel-originating calls
+ * from iBCS2 in 2.2 days.
+ */
+ return -EINVAL;
+ }
+ case SHMDT:
+ return sys_shmdt((char __user *)ptr);
+ case SHMGET:
+ return sys_shmget(first, second, third);
+ case SHMCTL:
+ return sys_shmctl(first, second,
+ (struct shmid_ds __user *) ptr);
+ default:
+ return -ENOSYS;
+ }
+}
+#endif
diff --git a/ipc/util.c b/ipc/util.c
new file mode 100644
index 00000000..75261a31
--- /dev/null
+++ b/ipc/util.c
@@ -0,0 +1,987 @@
+/*
+ * linux/ipc/util.c
+ * Copyright (C) 1992 Krishna Balasubramanian
+ *
+ * Sep 1997 - Call suser() last after "normal" permission checks so we
+ * get BSD style process accounting right.
+ * Occurs in several places in the IPC code.
+ * Chris Evans, <chris@ferret.lmh.ox.ac.uk>
+ * Nov 1999 - ipc helper functions, unified SMP locking
+ * Manfred Spraul <manfred@colorfullife.com>
+ * Oct 2002 - One lock per IPC id. RCU ipc_free for lock-free grow_ary().
+ * Mingming Cao <cmm@us.ibm.com>
+ * Mar 2006 - support for audit of ipc object properties
+ * Dustin Kirkland <dustin.kirkland@us.ibm.com>
+ * Jun 2006 - namespaces ssupport
+ * OpenVZ, SWsoft Inc.
+ * Pavel Emelianov <xemul@openvz.org>
+ */
+
+#include <linux/mm.h>
+#include <linux/shm.h>
+#include <linux/init.h>
+#include <linux/msg.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/capability.h>
+#include <linux/highuid.h>
+#include <linux/security.h>
+#include <linux/rcupdate.h>
+#include <linux/workqueue.h>
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
+#include <linux/audit.h>
+#include <linux/nsproxy.h>
+#include <linux/rwsem.h>
+#include <linux/memory.h>
+#include <linux/ipc_namespace.h>
+
+#include <asm/unistd.h>
+
+#include "util.h"
+
+struct ipc_proc_iface {
+ const char *path;
+ const char *header;
+ int ids;
+ int (*show)(struct seq_file *, void *);
+};
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+
+static void ipc_memory_notifier(struct work_struct *work)
+{
+ ipcns_notify(IPCNS_MEMCHANGED);
+}
+
+static DECLARE_WORK(ipc_memory_wq, ipc_memory_notifier);
+
+
+static int ipc_memory_callback(struct notifier_block *self,
+ unsigned long action, void *arg)
+{
+ switch (action) {
+ case MEM_ONLINE: /* memory successfully brought online */
+ case MEM_OFFLINE: /* or offline: it's time to recompute msgmni */
+ /*
+ * This is done by invoking the ipcns notifier chain with the
+ * IPC_MEMCHANGED event.
+ * In order not to keep the lock on the hotplug memory chain
+ * for too long, queue a work item that will, when waken up,
+ * activate the ipcns notification chain.
+ * No need to keep several ipc work items on the queue.
+ */
+ if (!work_pending(&ipc_memory_wq))
+ schedule_work(&ipc_memory_wq);
+ break;
+ case MEM_GOING_ONLINE:
+ case MEM_GOING_OFFLINE:
+ case MEM_CANCEL_ONLINE:
+ case MEM_CANCEL_OFFLINE:
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+/**
+ * ipc_init - initialise IPC subsystem
+ *
+ * The various system5 IPC resources (semaphores, messages and shared
+ * memory) are initialised
+ * A callback routine is registered into the memory hotplug notifier
+ * chain: since msgmni scales to lowmem this callback routine will be
+ * called upon successful memory add / remove to recompute msmgni.
+ */
+
+static int __init ipc_init(void)
+{
+ sem_init();
+ msg_init();
+ shm_init();
+ hotplug_memory_notifier(ipc_memory_callback, IPC_CALLBACK_PRI);
+ register_ipcns_notifier(&init_ipc_ns);
+ return 0;
+}
+__initcall(ipc_init);
+
+/**
+ * ipc_init_ids - initialise IPC identifiers
+ * @ids: Identifier set
+ *
+ * Set up the sequence range to use for the ipc identifier range (limited
+ * below IPCMNI) then initialise the ids idr.
+ */
+
+void ipc_init_ids(struct ipc_ids *ids)
+{
+ init_rwsem(&ids->rw_mutex);
+
+ ids->in_use = 0;
+ ids->seq = 0;
+ {
+ int seq_limit = INT_MAX/SEQ_MULTIPLIER;
+ if (seq_limit > USHRT_MAX)
+ ids->seq_max = USHRT_MAX;
+ else
+ ids->seq_max = seq_limit;
+ }
+
+ idr_init(&ids->ipcs_idr);
+}
+
+#ifdef CONFIG_PROC_FS
+static const struct file_operations sysvipc_proc_fops;
+/**
+ * ipc_init_proc_interface - Create a proc interface for sysipc types using a seq_file interface.
+ * @path: Path in procfs
+ * @header: Banner to be printed at the beginning of the file.
+ * @ids: ipc id table to iterate.
+ * @show: show routine.
+ */
+void __init ipc_init_proc_interface(const char *path, const char *header,
+ int ids, int (*show)(struct seq_file *, void *))
+{
+ struct proc_dir_entry *pde;
+ struct ipc_proc_iface *iface;
+
+ iface = kmalloc(sizeof(*iface), GFP_KERNEL);
+ if (!iface)
+ return;
+ iface->path = path;
+ iface->header = header;
+ iface->ids = ids;
+ iface->show = show;
+
+ pde = proc_create_data(path,
+ S_IRUGO, /* world readable */
+ NULL, /* parent dir */
+ &sysvipc_proc_fops,
+ iface);
+ if (!pde) {
+ kfree(iface);
+ }
+}
+#endif
+
+/**
+ * ipc_findkey - find a key in an ipc identifier set
+ * @ids: Identifier set
+ * @key: The key to find
+ *
+ * Requires ipc_ids.rw_mutex locked.
+ * Returns the LOCKED pointer to the ipc structure if found or NULL
+ * if not.
+ * If key is found ipc points to the owning ipc structure
+ */
+
+static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key)
+{
+ struct kern_ipc_perm *ipc;
+ int next_id;
+ int total;
+
+ for (total = 0, next_id = 0; total < ids->in_use; next_id++) {
+ ipc = idr_find(&ids->ipcs_idr, next_id);
+
+ if (ipc == NULL)
+ continue;
+
+ if (ipc->key != key) {
+ total++;
+ continue;
+ }
+
+ ipc_lock_by_ptr(ipc);
+ return ipc;
+ }
+
+ return NULL;
+}
+
+/**
+ * ipc_get_maxid - get the last assigned id
+ * @ids: IPC identifier set
+ *
+ * Called with ipc_ids.rw_mutex held.
+ */
+
+int ipc_get_maxid(struct ipc_ids *ids)
+{
+ struct kern_ipc_perm *ipc;
+ int max_id = -1;
+ int total, id;
+
+ if (ids->in_use == 0)
+ return -1;
+
+ if (ids->in_use == IPCMNI)
+ return IPCMNI - 1;
+
+ /* Look for the last assigned id */
+ total = 0;
+ for (id = 0; id < IPCMNI && total < ids->in_use; id++) {
+ ipc = idr_find(&ids->ipcs_idr, id);
+ if (ipc != NULL) {
+ max_id = id;
+ total++;
+ }
+ }
+ return max_id;
+}
+
+/**
+ * ipc_addid - add an IPC identifier
+ * @ids: IPC identifier set
+ * @new: new IPC permission set
+ * @size: limit for the number of used ids
+ *
+ * Add an entry 'new' to the IPC ids idr. The permissions object is
+ * initialised and the first free entry is set up and the id assigned
+ * is returned. The 'new' entry is returned in a locked state on success.
+ * On failure the entry is not locked and a negative err-code is returned.
+ *
+ * Called with ipc_ids.rw_mutex held as a writer.
+ */
+
+int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
+{
+ uid_t euid;
+ gid_t egid;
+ int id, err;
+
+ if (size > IPCMNI)
+ size = IPCMNI;
+
+ if (ids->in_use >= size)
+ return -ENOSPC;
+
+ spin_lock_init(&new->lock);
+ new->deleted = 0;
+ rcu_read_lock();
+ spin_lock(&new->lock);
+
+ err = idr_get_new(&ids->ipcs_idr, new, &id);
+ if (err) {
+ spin_unlock(&new->lock);
+ rcu_read_unlock();
+ return err;
+ }
+
+ ids->in_use++;
+
+ current_euid_egid(&euid, &egid);
+ new->cuid = new->uid = euid;
+ new->gid = new->cgid = egid;
+
+ new->seq = ids->seq++;
+ if(ids->seq > ids->seq_max)
+ ids->seq = 0;
+
+ new->id = ipc_buildid(id, new->seq);
+ return id;
+}
+
+/**
+ * ipcget_new - create a new ipc object
+ * @ns: namespace
+ * @ids: IPC identifer set
+ * @ops: the actual creation routine to call
+ * @params: its parameters
+ *
+ * This routine is called by sys_msgget, sys_semget() and sys_shmget()
+ * when the key is IPC_PRIVATE.
+ */
+static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
+ struct ipc_ops *ops, struct ipc_params *params)
+{
+ int err;
+retry:
+ err = idr_pre_get(&ids->ipcs_idr, GFP_KERNEL);
+
+ if (!err)
+ return -ENOMEM;
+
+ down_write(&ids->rw_mutex);
+ err = ops->getnew(ns, params);
+ up_write(&ids->rw_mutex);
+
+ if (err == -EAGAIN)
+ goto retry;
+
+ return err;
+}
+
+/**
+ * ipc_check_perms - check security and permissions for an IPC
+ * @ns: IPC namespace
+ * @ipcp: ipc permission set
+ * @ops: the actual security routine to call
+ * @params: its parameters
+ *
+ * This routine is called by sys_msgget(), sys_semget() and sys_shmget()
+ * when the key is not IPC_PRIVATE and that key already exists in the
+ * ids IDR.
+ *
+ * On success, the IPC id is returned.
+ *
+ * It is called with ipc_ids.rw_mutex and ipcp->lock held.
+ */
+static int ipc_check_perms(struct ipc_namespace *ns,
+ struct kern_ipc_perm *ipcp,
+ struct ipc_ops *ops,
+ struct ipc_params *params)
+{
+ int err;
+
+ if (ipcperms(ns, ipcp, params->flg))
+ err = -EACCES;
+ else {
+ err = ops->associate(ipcp, params->flg);
+ if (!err)
+ err = ipcp->id;
+ }
+
+ return err;
+}
+
+/**
+ * ipcget_public - get an ipc object or create a new one
+ * @ns: namespace
+ * @ids: IPC identifer set
+ * @ops: the actual creation routine to call
+ * @params: its parameters
+ *
+ * This routine is called by sys_msgget, sys_semget() and sys_shmget()
+ * when the key is not IPC_PRIVATE.
+ * It adds a new entry if the key is not found and does some permission
+ * / security checkings if the key is found.
+ *
+ * On success, the ipc id is returned.
+ */
+static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
+ struct ipc_ops *ops, struct ipc_params *params)
+{
+ struct kern_ipc_perm *ipcp;
+ int flg = params->flg;
+ int err;
+retry:
+ err = idr_pre_get(&ids->ipcs_idr, GFP_KERNEL);
+
+ /*
+ * Take the lock as a writer since we are potentially going to add
+ * a new entry + read locks are not "upgradable"
+ */
+ down_write(&ids->rw_mutex);
+ ipcp = ipc_findkey(ids, params->key);
+ if (ipcp == NULL) {
+ /* key not used */
+ if (!(flg & IPC_CREAT))
+ err = -ENOENT;
+ else if (!err)
+ err = -ENOMEM;
+ else
+ err = ops->getnew(ns, params);
+ } else {
+ /* ipc object has been locked by ipc_findkey() */
+
+ if (flg & IPC_CREAT && flg & IPC_EXCL)
+ err = -EEXIST;
+ else {
+ err = 0;
+ if (ops->more_checks)
+ err = ops->more_checks(ipcp, params);
+ if (!err)
+ /*
+ * ipc_check_perms returns the IPC id on
+ * success
+ */
+ err = ipc_check_perms(ns, ipcp, ops, params);
+ }
+ ipc_unlock(ipcp);
+ }
+ up_write(&ids->rw_mutex);
+
+ if (err == -EAGAIN)
+ goto retry;
+
+ return err;
+}
+
+
+/**
+ * ipc_rmid - remove an IPC identifier
+ * @ids: IPC identifier set
+ * @ipcp: ipc perm structure containing the identifier to remove
+ *
+ * ipc_ids.rw_mutex (as a writer) and the spinlock for this ID are held
+ * before this function is called, and remain locked on the exit.
+ */
+
+void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)
+{
+ int lid = ipcid_to_idx(ipcp->id);
+
+ idr_remove(&ids->ipcs_idr, lid);
+
+ ids->in_use--;
+
+ ipcp->deleted = 1;
+
+ return;
+}
+
+/**
+ * ipc_alloc - allocate ipc space
+ * @size: size desired
+ *
+ * Allocate memory from the appropriate pools and return a pointer to it.
+ * NULL is returned if the allocation fails
+ */
+
+void* ipc_alloc(int size)
+{
+ void* out;
+ if(size > PAGE_SIZE)
+ out = vmalloc(size);
+ else
+ out = kmalloc(size, GFP_KERNEL);
+ return out;
+}
+
+/**
+ * ipc_free - free ipc space
+ * @ptr: pointer returned by ipc_alloc
+ * @size: size of block
+ *
+ * Free a block created with ipc_alloc(). The caller must know the size
+ * used in the allocation call.
+ */
+
+void ipc_free(void* ptr, int size)
+{
+ if(size > PAGE_SIZE)
+ vfree(ptr);
+ else
+ kfree(ptr);
+}
+
+/*
+ * rcu allocations:
+ * There are three headers that are prepended to the actual allocation:
+ * - during use: ipc_rcu_hdr.
+ * - during the rcu grace period: ipc_rcu_grace.
+ * - [only if vmalloc]: ipc_rcu_sched.
+ * Their lifetime doesn't overlap, thus the headers share the same memory.
+ * Unlike a normal union, they are right-aligned, thus some container_of
+ * forward/backward casting is necessary:
+ */
+struct ipc_rcu_hdr
+{
+ int refcount;
+ int is_vmalloc;
+ void *data[0];
+};
+
+
+struct ipc_rcu_grace
+{
+ struct rcu_head rcu;
+ /* "void *" makes sure alignment of following data is sane. */
+ void *data[0];
+};
+
+struct ipc_rcu_sched
+{
+ struct work_struct work;
+ /* "void *" makes sure alignment of following data is sane. */
+ void *data[0];
+};
+
+#define HDRLEN_KMALLOC (sizeof(struct ipc_rcu_grace) > sizeof(struct ipc_rcu_hdr) ? \
+ sizeof(struct ipc_rcu_grace) : sizeof(struct ipc_rcu_hdr))
+#define HDRLEN_VMALLOC (sizeof(struct ipc_rcu_sched) > HDRLEN_KMALLOC ? \
+ sizeof(struct ipc_rcu_sched) : HDRLEN_KMALLOC)
+
+static inline int rcu_use_vmalloc(int size)
+{
+ /* Too big for a single page? */
+ if (HDRLEN_KMALLOC + size > PAGE_SIZE)
+ return 1;
+ return 0;
+}
+
+/**
+ * ipc_rcu_alloc - allocate ipc and rcu space
+ * @size: size desired
+ *
+ * Allocate memory for the rcu header structure + the object.
+ * Returns the pointer to the object.
+ * NULL is returned if the allocation fails.
+ */
+
+void* ipc_rcu_alloc(int size)
+{
+ void* out;
+ /*
+ * We prepend the allocation with the rcu struct, and
+ * workqueue if necessary (for vmalloc).
+ */
+ if (rcu_use_vmalloc(size)) {
+ out = vmalloc(HDRLEN_VMALLOC + size);
+ if (out) {
+ out += HDRLEN_VMALLOC;
+ container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1;
+ container_of(out, struct ipc_rcu_hdr, data)->refcount = 1;
+ }
+ } else {
+ out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL);
+ if (out) {
+ out += HDRLEN_KMALLOC;
+ container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0;
+ container_of(out, struct ipc_rcu_hdr, data)->refcount = 1;
+ }
+ }
+
+ return out;
+}
+
+void ipc_rcu_getref(void *ptr)
+{
+ container_of(ptr, struct ipc_rcu_hdr, data)->refcount++;
+}
+
+static void ipc_do_vfree(struct work_struct *work)
+{
+ vfree(container_of(work, struct ipc_rcu_sched, work));
+}
+
+/**
+ * ipc_schedule_free - free ipc + rcu space
+ * @head: RCU callback structure for queued work
+ *
+ * Since RCU callback function is called in bh,
+ * we need to defer the vfree to schedule_work().
+ */
+static void ipc_schedule_free(struct rcu_head *head)
+{
+ struct ipc_rcu_grace *grace;
+ struct ipc_rcu_sched *sched;
+
+ grace = container_of(head, struct ipc_rcu_grace, rcu);
+ sched = container_of(&(grace->data[0]), struct ipc_rcu_sched,
+ data[0]);
+
+ INIT_WORK(&sched->work, ipc_do_vfree);
+ schedule_work(&sched->work);
+}
+
+void ipc_rcu_putref(void *ptr)
+{
+ if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0)
+ return;
+
+ if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
+ call_rcu(&container_of(ptr, struct ipc_rcu_grace, data)->rcu,
+ ipc_schedule_free);
+ } else {
+ kfree_rcu(container_of(ptr, struct ipc_rcu_grace, data), rcu);
+ }
+}
+
+/**
+ * ipcperms - check IPC permissions
+ * @ns: IPC namespace
+ * @ipcp: IPC permission set
+ * @flag: desired permission set.
+ *
+ * Check user, group, other permissions for access
+ * to ipc resources. return 0 if allowed
+ *
+ * @flag will most probably be 0 or S_...UGO from <linux/stat.h>
+ */
+
+int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flag)
+{
+ uid_t euid = current_euid();
+ int requested_mode, granted_mode;
+
+ audit_ipc_obj(ipcp);
+ requested_mode = (flag >> 6) | (flag >> 3) | flag;
+ granted_mode = ipcp->mode;
+ if (euid == ipcp->cuid ||
+ euid == ipcp->uid)
+ granted_mode >>= 6;
+ else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid))
+ granted_mode >>= 3;
+ /* is there some bit set in requested_mode but not in granted_mode? */
+ if ((requested_mode & ~granted_mode & 0007) &&
+ !ns_capable(ns->user_ns, CAP_IPC_OWNER))
+ return -1;
+
+ return security_ipc_permission(ipcp, flag);
+}
+
+/*
+ * Functions to convert between the kern_ipc_perm structure and the
+ * old/new ipc_perm structures
+ */
+
+/**
+ * kernel_to_ipc64_perm - convert kernel ipc permissions to user
+ * @in: kernel permissions
+ * @out: new style IPC permissions
+ *
+ * Turn the kernel object @in into a set of permissions descriptions
+ * for returning to userspace (@out).
+ */
+
+
+void kernel_to_ipc64_perm (struct kern_ipc_perm *in, struct ipc64_perm *out)
+{
+ out->key = in->key;
+ out->uid = in->uid;
+ out->gid = in->gid;
+ out->cuid = in->cuid;
+ out->cgid = in->cgid;
+ out->mode = in->mode;
+ out->seq = in->seq;
+}
+
+/**
+ * ipc64_perm_to_ipc_perm - convert new ipc permissions to old
+ * @in: new style IPC permissions
+ * @out: old style IPC permissions
+ *
+ * Turn the new style permissions object @in into a compatibility
+ * object and store it into the @out pointer.
+ */
+
+void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out)
+{
+ out->key = in->key;
+ SET_UID(out->uid, in->uid);
+ SET_GID(out->gid, in->gid);
+ SET_UID(out->cuid, in->cuid);
+ SET_GID(out->cgid, in->cgid);
+ out->mode = in->mode;
+ out->seq = in->seq;
+}
+
+/**
+ * ipc_lock - Lock an ipc structure without rw_mutex held
+ * @ids: IPC identifier set
+ * @id: ipc id to look for
+ *
+ * Look for an id in the ipc ids idr and lock the associated ipc object.
+ *
+ * The ipc object is locked on exit.
+ */
+
+struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
+{
+ struct kern_ipc_perm *out;
+ int lid = ipcid_to_idx(id);
+
+ rcu_read_lock();
+ out = idr_find(&ids->ipcs_idr, lid);
+ if (out == NULL) {
+ rcu_read_unlock();
+ return ERR_PTR(-EINVAL);
+ }
+
+ spin_lock(&out->lock);
+
+ /* ipc_rmid() may have already freed the ID while ipc_lock
+ * was spinning: here verify that the structure is still valid
+ */
+ if (out->deleted) {
+ spin_unlock(&out->lock);
+ rcu_read_unlock();
+ return ERR_PTR(-EINVAL);
+ }
+
+ return out;
+}
+
+struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id)
+{
+ struct kern_ipc_perm *out;
+
+ out = ipc_lock(ids, id);
+ if (IS_ERR(out))
+ return out;
+
+ if (ipc_checkid(out, id)) {
+ ipc_unlock(out);
+ return ERR_PTR(-EIDRM);
+ }
+
+ return out;
+}
+
+/**
+ * ipcget - Common sys_*get() code
+ * @ns : namsepace
+ * @ids : IPC identifier set
+ * @ops : operations to be called on ipc object creation, permission checks
+ * and further checks
+ * @params : the parameters needed by the previous operations.
+ *
+ * Common routine called by sys_msgget(), sys_semget() and sys_shmget().
+ */
+int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
+ struct ipc_ops *ops, struct ipc_params *params)
+{
+ if (params->key == IPC_PRIVATE)
+ return ipcget_new(ns, ids, ops, params);
+ else
+ return ipcget_public(ns, ids, ops, params);
+}
+
+/**
+ * ipc_update_perm - update the permissions of an IPC.
+ * @in: the permission given as input.
+ * @out: the permission of the ipc to set.
+ */
+void ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
+{
+ out->uid = in->uid;
+ out->gid = in->gid;
+ out->mode = (out->mode & ~S_IRWXUGO)
+ | (in->mode & S_IRWXUGO);
+}
+
+/**
+ * ipcctl_pre_down - retrieve an ipc and check permissions for some IPC_XXX cmd
+ * @ns: the ipc namespace
+ * @ids: the table of ids where to look for the ipc
+ * @id: the id of the ipc to retrieve
+ * @cmd: the cmd to check
+ * @perm: the permission to set
+ * @extra_perm: one extra permission parameter used by msq
+ *
+ * This function does some common audit and permissions check for some IPC_XXX
+ * cmd and is called from semctl_down, shmctl_down and msgctl_down.
+ * It must be called without any lock held and
+ * - retrieves the ipc with the given id in the given table.
+ * - performs some audit and permission check, depending on the given cmd
+ * - returns the ipc with both ipc and rw_mutex locks held in case of success
+ * or an err-code without any lock held otherwise.
+ */
+struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
+ struct ipc_ids *ids, int id, int cmd,
+ struct ipc64_perm *perm, int extra_perm)
+{
+ struct kern_ipc_perm *ipcp;
+ uid_t euid;
+ int err;
+
+ down_write(&ids->rw_mutex);
+ ipcp = ipc_lock_check(ids, id);
+ if (IS_ERR(ipcp)) {
+ err = PTR_ERR(ipcp);
+ goto out_up;
+ }
+
+ audit_ipc_obj(ipcp);
+ if (cmd == IPC_SET)
+ audit_ipc_set_perm(extra_perm, perm->uid,
+ perm->gid, perm->mode);
+
+ euid = current_euid();
+ if (euid == ipcp->cuid || euid == ipcp->uid ||
+ ns_capable(ns->user_ns, CAP_SYS_ADMIN))
+ return ipcp;
+
+ err = -EPERM;
+ ipc_unlock(ipcp);
+out_up:
+ up_write(&ids->rw_mutex);
+ return ERR_PTR(err);
+}
+
+#ifdef __ARCH_WANT_IPC_PARSE_VERSION
+
+
+/**
+ * ipc_parse_version - IPC call version
+ * @cmd: pointer to command
+ *
+ * Return IPC_64 for new style IPC and IPC_OLD for old style IPC.
+ * The @cmd value is turned from an encoding command and version into
+ * just the command code.
+ */
+
+int ipc_parse_version (int *cmd)
+{
+ if (*cmd & IPC_64) {
+ *cmd ^= IPC_64;
+ return IPC_64;
+ } else {
+ return IPC_OLD;
+ }
+}
+
+#endif /* __ARCH_WANT_IPC_PARSE_VERSION */
+
+#ifdef CONFIG_PROC_FS
+struct ipc_proc_iter {
+ struct ipc_namespace *ns;
+ struct ipc_proc_iface *iface;
+};
+
+/*
+ * This routine locks the ipc structure found at least at position pos.
+ */
+static struct kern_ipc_perm *sysvipc_find_ipc(struct ipc_ids *ids, loff_t pos,
+ loff_t *new_pos)
+{
+ struct kern_ipc_perm *ipc;
+ int total, id;
+
+ total = 0;
+ for (id = 0; id < pos && total < ids->in_use; id++) {
+ ipc = idr_find(&ids->ipcs_idr, id);
+ if (ipc != NULL)
+ total++;
+ }
+
+ if (total >= ids->in_use)
+ return NULL;
+
+ for ( ; pos < IPCMNI; pos++) {
+ ipc = idr_find(&ids->ipcs_idr, pos);
+ if (ipc != NULL) {
+ *new_pos = pos + 1;
+ ipc_lock_by_ptr(ipc);
+ return ipc;
+ }
+ }
+
+ /* Out of range - return NULL to terminate iteration */
+ return NULL;
+}
+
+static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos)
+{
+ struct ipc_proc_iter *iter = s->private;
+ struct ipc_proc_iface *iface = iter->iface;
+ struct kern_ipc_perm *ipc = it;
+
+ /* If we had an ipc id locked before, unlock it */
+ if (ipc && ipc != SEQ_START_TOKEN)
+ ipc_unlock(ipc);
+
+ return sysvipc_find_ipc(&iter->ns->ids[iface->ids], *pos, pos);
+}
+
+/*
+ * File positions: pos 0 -> header, pos n -> ipc id = n - 1.
+ * SeqFile iterator: iterator value locked ipc pointer or SEQ_TOKEN_START.
+ */
+static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos)
+{
+ struct ipc_proc_iter *iter = s->private;
+ struct ipc_proc_iface *iface = iter->iface;
+ struct ipc_ids *ids;
+
+ ids = &iter->ns->ids[iface->ids];
+
+ /*
+ * Take the lock - this will be released by the corresponding
+ * call to stop().
+ */
+ down_read(&ids->rw_mutex);
+
+ /* pos < 0 is invalid */
+ if (*pos < 0)
+ return NULL;
+
+ /* pos == 0 means header */
+ if (*pos == 0)
+ return SEQ_START_TOKEN;
+
+ /* Find the (pos-1)th ipc */
+ return sysvipc_find_ipc(ids, *pos - 1, pos);
+}
+
+static void sysvipc_proc_stop(struct seq_file *s, void *it)
+{
+ struct kern_ipc_perm *ipc = it;
+ struct ipc_proc_iter *iter = s->private;
+ struct ipc_proc_iface *iface = iter->iface;
+ struct ipc_ids *ids;
+
+ /* If we had a locked structure, release it */
+ if (ipc && ipc != SEQ_START_TOKEN)
+ ipc_unlock(ipc);
+
+ ids = &iter->ns->ids[iface->ids];
+ /* Release the lock we took in start() */
+ up_read(&ids->rw_mutex);
+}
+
+static int sysvipc_proc_show(struct seq_file *s, void *it)
+{
+ struct ipc_proc_iter *iter = s->private;
+ struct ipc_proc_iface *iface = iter->iface;
+
+ if (it == SEQ_START_TOKEN)
+ return seq_puts(s, iface->header);
+
+ return iface->show(s, it);
+}
+
+static const struct seq_operations sysvipc_proc_seqops = {
+ .start = sysvipc_proc_start,
+ .stop = sysvipc_proc_stop,
+ .next = sysvipc_proc_next,
+ .show = sysvipc_proc_show,
+};
+
+static int sysvipc_proc_open(struct inode *inode, struct file *file)
+{
+ int ret;
+ struct seq_file *seq;
+ struct ipc_proc_iter *iter;
+
+ ret = -ENOMEM;
+ iter = kmalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ goto out;
+
+ ret = seq_open(file, &sysvipc_proc_seqops);
+ if (ret)
+ goto out_kfree;
+
+ seq = file->private_data;
+ seq->private = iter;
+
+ iter->iface = PDE(inode)->data;
+ iter->ns = get_ipc_ns(current->nsproxy->ipc_ns);
+out:
+ return ret;
+out_kfree:
+ kfree(iter);
+ goto out;
+}
+
+static int sysvipc_proc_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq = file->private_data;
+ struct ipc_proc_iter *iter = seq->private;
+ put_ipc_ns(iter->ns);
+ return seq_release_private(inode, file);
+}
+
+static const struct file_operations sysvipc_proc_fops = {
+ .open = sysvipc_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = sysvipc_proc_release,
+};
+#endif /* CONFIG_PROC_FS */
diff --git a/ipc/util.h b/ipc/util.h
new file mode 100644
index 00000000..6f5c20be
--- /dev/null
+++ b/ipc/util.h
@@ -0,0 +1,178 @@
+/*
+ * linux/ipc/util.h
+ * Copyright (C) 1999 Christoph Rohland
+ *
+ * ipc helper functions (c) 1999 Manfred Spraul <manfred@colorfullife.com>
+ * namespaces support. 2006 OpenVZ, SWsoft Inc.
+ * Pavel Emelianov <xemul@openvz.org>
+ */
+
+#ifndef _IPC_UTIL_H
+#define _IPC_UTIL_H
+
+#include <linux/unistd.h>
+#include <linux/err.h>
+
+#define SEQ_MULTIPLIER (IPCMNI)
+
+void sem_init (void);
+void msg_init (void);
+void shm_init (void);
+
+struct ipc_namespace;
+
+#ifdef CONFIG_POSIX_MQUEUE
+extern void mq_clear_sbinfo(struct ipc_namespace *ns);
+extern void mq_put_mnt(struct ipc_namespace *ns);
+#else
+static inline void mq_clear_sbinfo(struct ipc_namespace *ns) { }
+static inline void mq_put_mnt(struct ipc_namespace *ns) { }
+#endif
+
+#ifdef CONFIG_SYSVIPC
+void sem_init_ns(struct ipc_namespace *ns);
+void msg_init_ns(struct ipc_namespace *ns);
+void shm_init_ns(struct ipc_namespace *ns);
+
+void sem_exit_ns(struct ipc_namespace *ns);
+void msg_exit_ns(struct ipc_namespace *ns);
+void shm_exit_ns(struct ipc_namespace *ns);
+#else
+static inline void sem_init_ns(struct ipc_namespace *ns) { }
+static inline void msg_init_ns(struct ipc_namespace *ns) { }
+static inline void shm_init_ns(struct ipc_namespace *ns) { }
+
+static inline void sem_exit_ns(struct ipc_namespace *ns) { }
+static inline void msg_exit_ns(struct ipc_namespace *ns) { }
+static inline void shm_exit_ns(struct ipc_namespace *ns) { }
+#endif
+
+/*
+ * Structure that holds the parameters needed by the ipc operations
+ * (see after)
+ */
+struct ipc_params {
+ key_t key;
+ int flg;
+ union {
+ size_t size; /* for shared memories */
+ int nsems; /* for semaphores */
+ } u; /* holds the getnew() specific param */
+};
+
+/*
+ * Structure that holds some ipc operations. This structure is used to unify
+ * the calls to sys_msgget(), sys_semget(), sys_shmget()
+ * . routine to call to create a new ipc object. Can be one of newque,
+ * newary, newseg
+ * . routine to call to check permissions for a new ipc object.
+ * Can be one of security_msg_associate, security_sem_associate,
+ * security_shm_associate
+ * . routine to call for an extra check if needed
+ */
+struct ipc_ops {
+ int (*getnew) (struct ipc_namespace *, struct ipc_params *);
+ int (*associate) (struct kern_ipc_perm *, int);
+ int (*more_checks) (struct kern_ipc_perm *, struct ipc_params *);
+};
+
+struct seq_file;
+struct ipc_ids;
+
+void ipc_init_ids(struct ipc_ids *);
+#ifdef CONFIG_PROC_FS
+void __init ipc_init_proc_interface(const char *path, const char *header,
+ int ids, int (*show)(struct seq_file *, void *));
+#else
+#define ipc_init_proc_interface(path, header, ids, show) do {} while (0)
+#endif
+
+#define IPC_SEM_IDS 0
+#define IPC_MSG_IDS 1
+#define IPC_SHM_IDS 2
+
+#define ipcid_to_idx(id) ((id) % SEQ_MULTIPLIER)
+
+/* must be called with ids->rw_mutex acquired for writing */
+int ipc_addid(struct ipc_ids *, struct kern_ipc_perm *, int);
+
+/* must be called with ids->rw_mutex acquired for reading */
+int ipc_get_maxid(struct ipc_ids *);
+
+/* must be called with both locks acquired. */
+void ipc_rmid(struct ipc_ids *, struct kern_ipc_perm *);
+
+/* must be called with ipcp locked */
+int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flg);
+
+/* for rare, potentially huge allocations.
+ * both function can sleep
+ */
+void* ipc_alloc(int size);
+void ipc_free(void* ptr, int size);
+
+/*
+ * For allocation that need to be freed by RCU.
+ * Objects are reference counted, they start with reference count 1.
+ * getref increases the refcount, the putref call that reduces the recount
+ * to 0 schedules the rcu destruction. Caller must guarantee locking.
+ */
+void* ipc_rcu_alloc(int size);
+void ipc_rcu_getref(void *ptr);
+void ipc_rcu_putref(void *ptr);
+
+struct kern_ipc_perm *ipc_lock(struct ipc_ids *, int);
+
+void kernel_to_ipc64_perm(struct kern_ipc_perm *in, struct ipc64_perm *out);
+void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out);
+void ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out);
+struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
+ struct ipc_ids *ids, int id, int cmd,
+ struct ipc64_perm *perm, int extra_perm);
+
+#ifndef __ARCH_WANT_IPC_PARSE_VERSION
+ /* On IA-64, we always use the "64-bit version" of the IPC structures. */
+# define ipc_parse_version(cmd) IPC_64
+#else
+int ipc_parse_version (int *cmd);
+#endif
+
+extern void free_msg(struct msg_msg *msg);
+extern struct msg_msg *load_msg(const void __user *src, int len);
+extern int store_msg(void __user *dest, struct msg_msg *msg, int len);
+
+extern void recompute_msgmni(struct ipc_namespace *);
+
+static inline int ipc_buildid(int id, int seq)
+{
+ return SEQ_MULTIPLIER * seq + id;
+}
+
+/*
+ * Must be called with ipcp locked
+ */
+static inline int ipc_checkid(struct kern_ipc_perm *ipcp, int uid)
+{
+ if (uid / SEQ_MULTIPLIER != ipcp->seq)
+ return 1;
+ return 0;
+}
+
+static inline void ipc_lock_by_ptr(struct kern_ipc_perm *perm)
+{
+ rcu_read_lock();
+ spin_lock(&perm->lock);
+}
+
+static inline void ipc_unlock(struct kern_ipc_perm *perm)
+{
+ spin_unlock(&perm->lock);
+ rcu_read_unlock();
+}
+
+struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id);
+int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
+ struct ipc_ops *ops, struct ipc_params *params);
+void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
+ void (*free)(struct ipc_namespace *, struct kern_ipc_perm *));
+#endif
generated by cgit (git 2.34.1) at 2024-12-20 19:21:55 +0000