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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /kernel/sys.c | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'kernel/sys.c')
-rw-r--r-- | kernel/sys.c | 2197 |
1 files changed, 2197 insertions, 0 deletions
diff --git a/kernel/sys.c b/kernel/sys.c new file mode 100644 index 00000000..c4fe1b86 --- /dev/null +++ b/kernel/sys.c @@ -0,0 +1,2197 @@ +/* + * linux/kernel/sys.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + */ + +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/utsname.h> +#include <linux/mman.h> +#include <linux/reboot.h> +#include <linux/prctl.h> +#include <linux/highuid.h> +#include <linux/fs.h> +#include <linux/kmod.h> +#include <linux/perf_event.h> +#include <linux/resource.h> +#include <linux/kernel.h> +#include <linux/kexec.h> +#include <linux/workqueue.h> +#include <linux/capability.h> +#include <linux/device.h> +#include <linux/key.h> +#include <linux/times.h> +#include <linux/posix-timers.h> +#include <linux/security.h> +#include <linux/dcookies.h> +#include <linux/suspend.h> +#include <linux/tty.h> +#include <linux/signal.h> +#include <linux/cn_proc.h> +#include <linux/getcpu.h> +#include <linux/task_io_accounting_ops.h> +#include <linux/seccomp.h> +#include <linux/cpu.h> +#include <linux/personality.h> +#include <linux/ptrace.h> +#include <linux/fs_struct.h> +#include <linux/gfp.h> +#include <linux/syscore_ops.h> +#include <linux/version.h> +#include <linux/ctype.h> + +#include <linux/compat.h> +#include <linux/syscalls.h> +#include <linux/kprobes.h> +#include <linux/user_namespace.h> +#include <linux/mtd/mtd.h> + +#include <linux/kmsg_dump.h> +/* Move somewhere else to avoid recompiling? */ +#include <generated/utsrelease.h> + +#include <asm/uaccess.h> +#include <asm/io.h> +#include <asm/unistd.h> + +#ifndef SET_UNALIGN_CTL +# define SET_UNALIGN_CTL(a,b) (-EINVAL) +#endif +#ifndef GET_UNALIGN_CTL +# define GET_UNALIGN_CTL(a,b) (-EINVAL) +#endif +#ifndef SET_FPEMU_CTL +# define SET_FPEMU_CTL(a,b) (-EINVAL) +#endif +#ifndef GET_FPEMU_CTL +# define GET_FPEMU_CTL(a,b) (-EINVAL) +#endif +#ifndef SET_FPEXC_CTL +# define SET_FPEXC_CTL(a,b) (-EINVAL) +#endif +#ifndef GET_FPEXC_CTL +# define GET_FPEXC_CTL(a,b) (-EINVAL) +#endif +#ifndef GET_ENDIAN +# define GET_ENDIAN(a,b) (-EINVAL) +#endif +#ifndef SET_ENDIAN +# define SET_ENDIAN(a,b) (-EINVAL) +#endif +#ifndef GET_TSC_CTL +# define GET_TSC_CTL(a) (-EINVAL) +#endif +#ifndef SET_TSC_CTL +# define SET_TSC_CTL(a) (-EINVAL) +#endif + +/* + * this is where the system-wide overflow UID and GID are defined, for + * architectures that now have 32-bit UID/GID but didn't in the past + */ + +int overflowuid = DEFAULT_OVERFLOWUID; +int overflowgid = DEFAULT_OVERFLOWGID; + +#ifdef CONFIG_UID16 +EXPORT_SYMBOL(overflowuid); +EXPORT_SYMBOL(overflowgid); +#endif + +/* + * the same as above, but for filesystems which can only store a 16-bit + * UID and GID. as such, this is needed on all architectures + */ + +int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; +int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; + +EXPORT_SYMBOL(fs_overflowuid); +EXPORT_SYMBOL(fs_overflowgid); + +/* + * this indicates whether you can reboot with ctrl-alt-del: the default is yes + */ + +int C_A_D = 1; +struct pid *cad_pid; +EXPORT_SYMBOL(cad_pid); + +/* + * If set, this is used for preparing the system to power off. + */ + +void (*pm_power_off_prepare)(void); + +/* + * Returns true if current's euid is same as p's uid or euid, + * or has CAP_SYS_NICE to p's user_ns. + * + * Called with rcu_read_lock, creds are safe + */ +static bool set_one_prio_perm(struct task_struct *p) +{ + const struct cred *cred = current_cred(), *pcred = __task_cred(p); + + if (pcred->user->user_ns == cred->user->user_ns && + (pcred->uid == cred->euid || + pcred->euid == cred->euid)) + return true; + if (ns_capable(pcred->user->user_ns, CAP_SYS_NICE)) + return true; + return false; +} + +/* + * set the priority of a task + * - the caller must hold the RCU read lock + */ +static int set_one_prio(struct task_struct *p, int niceval, int error) +{ + int no_nice; + + if (!set_one_prio_perm(p)) { + error = -EPERM; + goto out; + } + if (niceval < task_nice(p) && !can_nice(p, niceval)) { + error = -EACCES; + goto out; + } + no_nice = security_task_setnice(p, niceval); + if (no_nice) { + error = no_nice; + goto out; + } + if (error == -ESRCH) + error = 0; + set_user_nice(p, niceval); +out: + return error; +} + +SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) +{ + struct task_struct *g, *p; + struct user_struct *user; + const struct cred *cred = current_cred(); + int error = -EINVAL; + struct pid *pgrp; + + if (which > PRIO_USER || which < PRIO_PROCESS) + goto out; + + /* normalize: avoid signed division (rounding problems) */ + error = -ESRCH; + if (niceval < -20) + niceval = -20; + if (niceval > 19) + niceval = 19; + + rcu_read_lock(); + read_lock(&tasklist_lock); + switch (which) { + case PRIO_PROCESS: + if (who) + p = find_task_by_vpid(who); + else + p = current; + if (p) + error = set_one_prio(p, niceval, error); + break; + case PRIO_PGRP: + if (who) + pgrp = find_vpid(who); + else + pgrp = task_pgrp(current); + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { + error = set_one_prio(p, niceval, error); + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); + break; + case PRIO_USER: + user = (struct user_struct *) cred->user; + if (!who) + who = cred->uid; + else if ((who != cred->uid) && + !(user = find_user(who))) + goto out_unlock; /* No processes for this user */ + + do_each_thread(g, p) { + if (__task_cred(p)->uid == who) + error = set_one_prio(p, niceval, error); + } while_each_thread(g, p); + if (who != cred->uid) + free_uid(user); /* For find_user() */ + break; + } +out_unlock: + read_unlock(&tasklist_lock); + rcu_read_unlock(); +out: + return error; +} + +/* + * Ugh. To avoid negative return values, "getpriority()" will + * not return the normal nice-value, but a negated value that + * has been offset by 20 (ie it returns 40..1 instead of -20..19) + * to stay compatible. + */ +SYSCALL_DEFINE2(getpriority, int, which, int, who) +{ + struct task_struct *g, *p; + struct user_struct *user; + const struct cred *cred = current_cred(); + long niceval, retval = -ESRCH; + struct pid *pgrp; + + if (which > PRIO_USER || which < PRIO_PROCESS) + return -EINVAL; + + rcu_read_lock(); + read_lock(&tasklist_lock); + switch (which) { + case PRIO_PROCESS: + if (who) + p = find_task_by_vpid(who); + else + p = current; + if (p) { + niceval = 20 - task_nice(p); + if (niceval > retval) + retval = niceval; + } + break; + case PRIO_PGRP: + if (who) + pgrp = find_vpid(who); + else + pgrp = task_pgrp(current); + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { + niceval = 20 - task_nice(p); + if (niceval > retval) + retval = niceval; + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); + break; + case PRIO_USER: + user = (struct user_struct *) cred->user; + if (!who) + who = cred->uid; + else if ((who != cred->uid) && + !(user = find_user(who))) + goto out_unlock; /* No processes for this user */ + + do_each_thread(g, p) { + if (__task_cred(p)->uid == who) { + niceval = 20 - task_nice(p); + if (niceval > retval) + retval = niceval; + } + } while_each_thread(g, p); + if (who != cred->uid) + free_uid(user); /* for find_user() */ + break; + } +out_unlock: + read_unlock(&tasklist_lock); + rcu_read_unlock(); + + return retval; +} + +/** + * emergency_restart - reboot the system + * + * Without shutting down any hardware or taking any locks + * reboot the system. This is called when we know we are in + * trouble so this is our best effort to reboot. This is + * safe to call in interrupt context. + */ +void emergency_restart(void) +{ + kmsg_dump(KMSG_DUMP_EMERG); + machine_emergency_restart(); +} +EXPORT_SYMBOL_GPL(emergency_restart); + +void kernel_restart_prepare(char *cmd) +{ + blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); + system_state = SYSTEM_RESTART; + usermodehelper_disable(); + device_shutdown(); + syscore_shutdown(); +} +extern int wmt_setsyspara(char *varname, char *varval); +extern int wmt_getsyspara(char *varname, unsigned char *varval, int *varlen); +char *strtok(char *str, char *ctrl) +{ + char *p=str,*q=ctrl,*r; + while (p&&q&&*p&&*q) { + for(r=p,q=ctrl;*r&&*q&&*r==*q;r++,q++); + if(q&&*q) + p++; // not match change to next char + else { + *p='\0'; + break; + } // catch and return + } + return str; +} + +/** + * register_reboot_notifier - Register function to be called at reboot time + * @nb: Info about notifier function to be called + * + * Registers a function with the list of functions + * to be called at reboot time. + * + * Currently always returns zero, as blocking_notifier_chain_register() + * always returns zero. + */ +int register_reboot_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&reboot_notifier_list, nb); +} +EXPORT_SYMBOL(register_reboot_notifier); + +/** + * unregister_reboot_notifier - Unregister previously registered reboot notifier + * @nb: Hook to be unregistered + * + * Unregisters a previously registered reboot + * notifier function. + * + * Returns zero on success, or %-ENOENT on failure. + */ +int unregister_reboot_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&reboot_notifier_list, nb); +} +EXPORT_SYMBOL(unregister_reboot_notifier); + +/** + * kernel_restart - reboot the system + * @cmd: pointer to buffer containing command to execute for restart + * or %NULL + * + * Shutdown everything and perform a clean reboot. + * This is not safe to call in interrupt context. + */ +void kernel_restart(char *cmd) +{ + int ret = 0, searched = 0, len = 0x360, lockable = 0, unlock = 0, error; + char buf[0x360], *token = NULL, *p = NULL; + kernel_restart_prepare(cmd); + + ret = wmt_getsyspara("wmt.rsa.pem", buf, &len); + if (ret && ret != 10){ + printk("kernel_restart : ret %d\n",ret); + lockable = 0; + } + if (!cmd) { + printk(KERN_EMERG "Restarting system.\n"); + ret = wmt_getsyspara("boot-method", buf, &len); + if (ret) { + printk(KERN_EMERG "get env boot-method fail\n"); + goto NO_SET_ENV; + } + printk(KERN_EMERG "boot-method = %s\n", buf); + + p = strstr((char *)buf, "recovery"); + if (p == NULL) + goto NO_SET_ENV; + if (strcmp(p, "recovery") == 0) { + token = strtok((char *)buf, "recovery"); + if (token) { + if (lockable == 1) { + if (wmt_sf_prot == 0) + goto NO_SET_ENV; + ret = wmt_sf_prot(0); + unlock = 1; + if (ret) + goto env_end; + } + strcat(token, "normal"); + printk(KERN_EMERG "set boot-method = %s ", token); + ret = wmt_setsyspara("boot-method", token); + if (ret) + printk(KERN_EMERG " fail\n"); + else + printk(KERN_EMERG " success\n"); + + if (lockable == 1) { + ret = wmt_sf_prot(1); + unlock = 0; +env_end: + if (ret) + printk(KERN_EMERG "env lock check fail\n"); + } + } + } + } else { + printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); + ret = wmt_getsyspara("boot-method", buf, &len); + if (ret) { + printk(KERN_EMERG "get env boot-method fail\n"); + goto NO_SET_ENV; + } + printk(KERN_EMERG "boot-method = %s\n", buf); + /* //debug + if (strcmp(buf, "boot-nand") == 0) + strcat(buf, "-normal"); + printk(KERN_EMERG "boot-method = %s\n", buf); + */ + + if (strcmp(cmd, "recovery") == 0) { + p = strstr((char *)buf, "normal"); + if (p == NULL) + goto NO_SET_ENV; + if (strcmp(p, "normal") == 0) + searched = 1; + } else { + p = strstr((char *)buf, "recovery"); + if (p == NULL) + goto NO_SET_ENV; + if (strcmp(p, "recovery") == 0) + searched = 2; + } + + //printk(KERN_EMERG "searched = %s\n", p); + if (searched == 0 || p == NULL) { + goto NO_SET_ENV; + } else if (searched == 1) { + token = strtok((char *)buf, "normal"); + strcat(token, "recovery"); + } else if (searched == 2) { + token = strtok((char *)buf, "recovery"); + strcat(token, "normal"); + } + printk(KERN_EMERG "set boot-method = %s,lockable %d\n", token,lockable); + + if (token) { + if (lockable == 1) { + if (wmt_sf_prot == 0){ + goto NO_SET_ENV; + } + ret = wmt_sf_prot(0); + unlock = 1; + if (ret){ + goto env_set_end; + } + } + + ret = wmt_setsyspara("boot-method", token); + if (ret) + printk(KERN_EMERG "set env fail\n"); + else + printk(KERN_EMERG "set env success\n"); + + if (lockable == 1) { + ret = wmt_sf_prot(1); + unlock = 0; +env_set_end: + if (ret) + printk(KERN_EMERG "env lock check fail\n"); + } + } + } +NO_SET_ENV: + + if (lockable == 1 && unlock == 1) { + + ret = wmt_sf_prot(1); + if (ret) + printk(KERN_EMERG "env lock err\n"); + } + kmsg_dump(KMSG_DUMP_RESTART); + error = disable_nonboot_cpus(); + if (error) + printk("Lch-%s: disable_nonboot_cpus fail error %d\n",__func__,error); + machine_restart(cmd); + +} +EXPORT_SYMBOL_GPL(kernel_restart); + +static void kernel_shutdown_prepare(enum system_states state) +{ + blocking_notifier_call_chain(&reboot_notifier_list, + (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); + system_state = state; + usermodehelper_disable(); + device_shutdown(); +} +/** + * kernel_halt - halt the system + * + * Shutdown everything and perform a clean system halt. + */ +void kernel_halt(void) +{ + kernel_shutdown_prepare(SYSTEM_HALT); + syscore_shutdown(); + printk(KERN_EMERG "System halted.\n"); + kmsg_dump(KMSG_DUMP_HALT); + machine_halt(); +} + +EXPORT_SYMBOL_GPL(kernel_halt); + +/** + * kernel_power_off - power_off the system + * + * Shutdown everything and perform a clean system power_off. + */ +void kernel_power_off(void) +{ + kernel_shutdown_prepare(SYSTEM_POWER_OFF); + if (pm_power_off_prepare) + pm_power_off_prepare(); + disable_nonboot_cpus(); + syscore_shutdown(); + printk(KERN_EMERG "Power down.\n"); + kmsg_dump(KMSG_DUMP_POWEROFF); + machine_power_off(); +} +EXPORT_SYMBOL_GPL(kernel_power_off); + +static DEFINE_MUTEX(reboot_mutex); + +/* + * Reboot system call: for obvious reasons only root may call it, + * and even root needs to set up some magic numbers in the registers + * so that some mistake won't make this reboot the whole machine. + * You can also set the meaning of the ctrl-alt-del-key here. + * + * reboot doesn't sync: do that yourself before calling this. + */ +SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, + void __user *, arg) +{ + char buffer[256]; + int ret = 0; + + /* We only trust the superuser with rebooting the system. */ + if (!capable(CAP_SYS_BOOT)) + return -EPERM; + + /* For safety, we require "magic" arguments. */ + if (magic1 != LINUX_REBOOT_MAGIC1 || + (magic2 != LINUX_REBOOT_MAGIC2 && + magic2 != LINUX_REBOOT_MAGIC2A && + magic2 != LINUX_REBOOT_MAGIC2B && + magic2 != LINUX_REBOOT_MAGIC2C)) + return -EINVAL; + + /* + * If pid namespaces are enabled and the current task is in a child + * pid_namespace, the command is handled by reboot_pid_ns() which will + * call do_exit(). + */ + ret = reboot_pid_ns(task_active_pid_ns(current), cmd); + if (ret) + return ret; + + /* Instead of trying to make the power_off code look like + * halt when pm_power_off is not set do it the easy way. + */ + if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) + cmd = LINUX_REBOOT_CMD_HALT; + + mutex_lock(&reboot_mutex); + switch (cmd) { + case LINUX_REBOOT_CMD_RESTART: + kernel_restart(NULL); + break; + + case LINUX_REBOOT_CMD_CAD_ON: + C_A_D = 1; + break; + + case LINUX_REBOOT_CMD_CAD_OFF: + C_A_D = 0; + break; + + case LINUX_REBOOT_CMD_HALT: + kernel_halt(); + do_exit(0); + panic("cannot halt"); + + case LINUX_REBOOT_CMD_POWER_OFF: + kernel_power_off(); + do_exit(0); + break; + + case LINUX_REBOOT_CMD_RESTART2: + if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { + ret = -EFAULT; + break; + } + buffer[sizeof(buffer) - 1] = '\0'; + + kernel_restart(buffer); + break; + +#ifdef CONFIG_KEXEC + case LINUX_REBOOT_CMD_KEXEC: + ret = kernel_kexec(); + break; +#endif + +#ifdef CONFIG_HIBERNATION + case LINUX_REBOOT_CMD_SW_SUSPEND: + ret = hibernate(); + break; +#endif + + default: + ret = -EINVAL; + break; + } + mutex_unlock(&reboot_mutex); + return ret; +} + +static void deferred_cad(struct work_struct *dummy) +{ + kernel_restart(NULL); +} + +/* + * This function gets called by ctrl-alt-del - ie the keyboard interrupt. + * As it's called within an interrupt, it may NOT sync: the only choice + * is whether to reboot at once, or just ignore the ctrl-alt-del. + */ +void ctrl_alt_del(void) +{ + static DECLARE_WORK(cad_work, deferred_cad); + + if (C_A_D) + schedule_work(&cad_work); + else + kill_cad_pid(SIGINT, 1); +} + +/* + * Unprivileged users may change the real gid to the effective gid + * or vice versa. (BSD-style) + * + * If you set the real gid at all, or set the effective gid to a value not + * equal to the real gid, then the saved gid is set to the new effective gid. + * + * This makes it possible for a setgid program to completely drop its + * privileges, which is often a useful assertion to make when you are doing + * a security audit over a program. + * + * The general idea is that a program which uses just setregid() will be + * 100% compatible with BSD. A program which uses just setgid() will be + * 100% compatible with POSIX with saved IDs. + * + * SMP: There are not races, the GIDs are checked only by filesystem + * operations (as far as semantic preservation is concerned). + */ +SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) +{ + const struct cred *old; + struct cred *new; + int retval; + + new = prepare_creds(); + if (!new) + return -ENOMEM; + old = current_cred(); + + retval = -EPERM; + if (rgid != (gid_t) -1) { + if (old->gid == rgid || + old->egid == rgid || + nsown_capable(CAP_SETGID)) + new->gid = rgid; + else + goto error; + } + if (egid != (gid_t) -1) { + if (old->gid == egid || + old->egid == egid || + old->sgid == egid || + nsown_capable(CAP_SETGID)) + new->egid = egid; + else + goto error; + } + + if (rgid != (gid_t) -1 || + (egid != (gid_t) -1 && egid != old->gid)) + new->sgid = new->egid; + new->fsgid = new->egid; + + return commit_creds(new); + +error: + abort_creds(new); + return retval; +} + +/* + * setgid() is implemented like SysV w/ SAVED_IDS + * + * SMP: Same implicit races as above. + */ +SYSCALL_DEFINE1(setgid, gid_t, gid) +{ + const struct cred *old; + struct cred *new; + int retval; + + new = prepare_creds(); + if (!new) + return -ENOMEM; + old = current_cred(); + + retval = -EPERM; + if (nsown_capable(CAP_SETGID)) + new->gid = new->egid = new->sgid = new->fsgid = gid; + else if (gid == old->gid || gid == old->sgid) + new->egid = new->fsgid = gid; + else + goto error; + + return commit_creds(new); + +error: + abort_creds(new); + return retval; +} + +/* + * change the user struct in a credentials set to match the new UID + */ +static int set_user(struct cred *new) +{ + struct user_struct *new_user; + + new_user = alloc_uid(current_user_ns(), new->uid); + if (!new_user) + return -EAGAIN; + + /* + * We don't fail in case of NPROC limit excess here because too many + * poorly written programs don't check set*uid() return code, assuming + * it never fails if called by root. We may still enforce NPROC limit + * for programs doing set*uid()+execve() by harmlessly deferring the + * failure to the execve() stage. + */ + if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) && + new_user != INIT_USER) + current->flags |= PF_NPROC_EXCEEDED; + else + current->flags &= ~PF_NPROC_EXCEEDED; + + free_uid(new->user); + new->user = new_user; + return 0; +} + +/* + * Unprivileged users may change the real uid to the effective uid + * or vice versa. (BSD-style) + * + * If you set the real uid at all, or set the effective uid to a value not + * equal to the real uid, then the saved uid is set to the new effective uid. + * + * This makes it possible for a setuid program to completely drop its + * privileges, which is often a useful assertion to make when you are doing + * a security audit over a program. + * + * The general idea is that a program which uses just setreuid() will be + * 100% compatible with BSD. A program which uses just setuid() will be + * 100% compatible with POSIX with saved IDs. + */ +SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) +{ + const struct cred *old; + struct cred *new; + int retval; + + new = prepare_creds(); + if (!new) + return -ENOMEM; + old = current_cred(); + + retval = -EPERM; + if (ruid != (uid_t) -1) { + new->uid = ruid; + if (old->uid != ruid && + old->euid != ruid && + !nsown_capable(CAP_SETUID)) + goto error; + } + + if (euid != (uid_t) -1) { + new->euid = euid; + if (old->uid != euid && + old->euid != euid && + old->suid != euid && + !nsown_capable(CAP_SETUID)) + goto error; + } + + if (new->uid != old->uid) { + retval = set_user(new); + if (retval < 0) + goto error; + } + if (ruid != (uid_t) -1 || + (euid != (uid_t) -1 && euid != old->uid)) + new->suid = new->euid; + new->fsuid = new->euid; + + retval = security_task_fix_setuid(new, old, LSM_SETID_RE); + if (retval < 0) + goto error; + + return commit_creds(new); + +error: + abort_creds(new); + return retval; +} + +/* + * setuid() is implemented like SysV with SAVED_IDS + * + * Note that SAVED_ID's is deficient in that a setuid root program + * like sendmail, for example, cannot set its uid to be a normal + * user and then switch back, because if you're root, setuid() sets + * the saved uid too. If you don't like this, blame the bright people + * in the POSIX committee and/or USG. Note that the BSD-style setreuid() + * will allow a root program to temporarily drop privileges and be able to + * regain them by swapping the real and effective uid. + */ +SYSCALL_DEFINE1(setuid, uid_t, uid) +{ + const struct cred *old; + struct cred *new; + int retval; + + new = prepare_creds(); + if (!new) + return -ENOMEM; + old = current_cred(); + + retval = -EPERM; + if (nsown_capable(CAP_SETUID)) { + new->suid = new->uid = uid; + if (uid != old->uid) { + retval = set_user(new); + if (retval < 0) + goto error; + } + } else if (uid != old->uid && uid != new->suid) { + goto error; + } + + new->fsuid = new->euid = uid; + + retval = security_task_fix_setuid(new, old, LSM_SETID_ID); + if (retval < 0) + goto error; + + return commit_creds(new); + +error: + abort_creds(new); + return retval; +} + + +/* + * This function implements a generic ability to update ruid, euid, + * and suid. This allows you to implement the 4.4 compatible seteuid(). + */ +SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) +{ + const struct cred *old; + struct cred *new; + int retval; + + new = prepare_creds(); + if (!new) + return -ENOMEM; + + old = current_cred(); + + retval = -EPERM; + if (!nsown_capable(CAP_SETUID)) { + if (ruid != (uid_t) -1 && ruid != old->uid && + ruid != old->euid && ruid != old->suid) + goto error; + if (euid != (uid_t) -1 && euid != old->uid && + euid != old->euid && euid != old->suid) + goto error; + if (suid != (uid_t) -1 && suid != old->uid && + suid != old->euid && suid != old->suid) + goto error; + } + + if (ruid != (uid_t) -1) { + new->uid = ruid; + if (ruid != old->uid) { + retval = set_user(new); + if (retval < 0) + goto error; + } + } + if (euid != (uid_t) -1) + new->euid = euid; + if (suid != (uid_t) -1) + new->suid = suid; + new->fsuid = new->euid; + + retval = security_task_fix_setuid(new, old, LSM_SETID_RES); + if (retval < 0) + goto error; + + return commit_creds(new); + +error: + abort_creds(new); + return retval; +} + +SYSCALL_DEFINE3(getresuid, uid_t __user *, ruid, uid_t __user *, euid, uid_t __user *, suid) +{ + const struct cred *cred = current_cred(); + int retval; + + if (!(retval = put_user(cred->uid, ruid)) && + !(retval = put_user(cred->euid, euid))) + retval = put_user(cred->suid, suid); + + return retval; +} + +/* + * Same as above, but for rgid, egid, sgid. + */ +SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) +{ + const struct cred *old; + struct cred *new; + int retval; + + new = prepare_creds(); + if (!new) + return -ENOMEM; + old = current_cred(); + + retval = -EPERM; + if (!nsown_capable(CAP_SETGID)) { + if (rgid != (gid_t) -1 && rgid != old->gid && + rgid != old->egid && rgid != old->sgid) + goto error; + if (egid != (gid_t) -1 && egid != old->gid && + egid != old->egid && egid != old->sgid) + goto error; + if (sgid != (gid_t) -1 && sgid != old->gid && + sgid != old->egid && sgid != old->sgid) + goto error; + } + + if (rgid != (gid_t) -1) + new->gid = rgid; + if (egid != (gid_t) -1) + new->egid = egid; + if (sgid != (gid_t) -1) + new->sgid = sgid; + new->fsgid = new->egid; + + return commit_creds(new); + +error: + abort_creds(new); + return retval; +} + +SYSCALL_DEFINE3(getresgid, gid_t __user *, rgid, gid_t __user *, egid, gid_t __user *, sgid) +{ + const struct cred *cred = current_cred(); + int retval; + + if (!(retval = put_user(cred->gid, rgid)) && + !(retval = put_user(cred->egid, egid))) + retval = put_user(cred->sgid, sgid); + + return retval; +} + + +/* + * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This + * is used for "access()" and for the NFS daemon (letting nfsd stay at + * whatever uid it wants to). It normally shadows "euid", except when + * explicitly set by setfsuid() or for access.. + */ +SYSCALL_DEFINE1(setfsuid, uid_t, uid) +{ + const struct cred *old; + struct cred *new; + uid_t old_fsuid; + + new = prepare_creds(); + if (!new) + return current_fsuid(); + old = current_cred(); + old_fsuid = old->fsuid; + + if (uid == old->uid || uid == old->euid || + uid == old->suid || uid == old->fsuid || + nsown_capable(CAP_SETUID)) { + if (uid != old_fsuid) { + new->fsuid = uid; + if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) + goto change_okay; + } + } + + abort_creds(new); + return old_fsuid; + +change_okay: + commit_creds(new); + return old_fsuid; +} + +/* + * Samma på svenska.. + */ +SYSCALL_DEFINE1(setfsgid, gid_t, gid) +{ + const struct cred *old; + struct cred *new; + gid_t old_fsgid; + + new = prepare_creds(); + if (!new) + return current_fsgid(); + old = current_cred(); + old_fsgid = old->fsgid; + + if (gid == old->gid || gid == old->egid || + gid == old->sgid || gid == old->fsgid || + nsown_capable(CAP_SETGID)) { + if (gid != old_fsgid) { + new->fsgid = gid; + goto change_okay; + } + } + + abort_creds(new); + return old_fsgid; + +change_okay: + commit_creds(new); + return old_fsgid; +} + +void do_sys_times(struct tms *tms) +{ + cputime_t tgutime, tgstime, cutime, cstime; + + spin_lock_irq(¤t->sighand->siglock); + thread_group_times(current, &tgutime, &tgstime); + cutime = current->signal->cutime; + cstime = current->signal->cstime; + spin_unlock_irq(¤t->sighand->siglock); + tms->tms_utime = cputime_to_clock_t(tgutime); + tms->tms_stime = cputime_to_clock_t(tgstime); + tms->tms_cutime = cputime_to_clock_t(cutime); + tms->tms_cstime = cputime_to_clock_t(cstime); +} + +SYSCALL_DEFINE1(times, struct tms __user *, tbuf) +{ + if (tbuf) { + struct tms tmp; + + do_sys_times(&tmp); + if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) + return -EFAULT; + } + force_successful_syscall_return(); + return (long) jiffies_64_to_clock_t(get_jiffies_64()); +} + +/* + * This needs some heavy checking ... + * I just haven't the stomach for it. I also don't fully + * understand sessions/pgrp etc. Let somebody who does explain it. + * + * OK, I think I have the protection semantics right.... this is really + * only important on a multi-user system anyway, to make sure one user + * can't send a signal to a process owned by another. -TYT, 12/12/91 + * + * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. + * LBT 04.03.94 + */ +SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) +{ + struct task_struct *p; + struct task_struct *group_leader = current->group_leader; + struct pid *pgrp; + int err; + + if (!pid) + pid = task_pid_vnr(group_leader); + if (!pgid) + pgid = pid; + if (pgid < 0) + return -EINVAL; + rcu_read_lock(); + + /* From this point forward we keep holding onto the tasklist lock + * so that our parent does not change from under us. -DaveM + */ + write_lock_irq(&tasklist_lock); + + err = -ESRCH; + p = find_task_by_vpid(pid); + if (!p) + goto out; + + err = -EINVAL; + if (!thread_group_leader(p)) + goto out; + + if (same_thread_group(p->real_parent, group_leader)) { + err = -EPERM; + if (task_session(p) != task_session(group_leader)) + goto out; + err = -EACCES; + if (p->did_exec) + goto out; + } else { + err = -ESRCH; + if (p != group_leader) + goto out; + } + + err = -EPERM; + if (p->signal->leader) + goto out; + + pgrp = task_pid(p); + if (pgid != pid) { + struct task_struct *g; + + pgrp = find_vpid(pgid); + g = pid_task(pgrp, PIDTYPE_PGID); + if (!g || task_session(g) != task_session(group_leader)) + goto out; + } + + err = security_task_setpgid(p, pgid); + if (err) + goto out; + + if (task_pgrp(p) != pgrp) + change_pid(p, PIDTYPE_PGID, pgrp); + + err = 0; +out: + /* All paths lead to here, thus we are safe. -DaveM */ + write_unlock_irq(&tasklist_lock); + rcu_read_unlock(); + return err; +} + +SYSCALL_DEFINE1(getpgid, pid_t, pid) +{ + struct task_struct *p; + struct pid *grp; + int retval; + + rcu_read_lock(); + if (!pid) + grp = task_pgrp(current); + else { + retval = -ESRCH; + p = find_task_by_vpid(pid); + if (!p) + goto out; + grp = task_pgrp(p); + if (!grp) + goto out; + + retval = security_task_getpgid(p); + if (retval) + goto out; + } + retval = pid_vnr(grp); +out: + rcu_read_unlock(); + return retval; +} + +#ifdef __ARCH_WANT_SYS_GETPGRP + +SYSCALL_DEFINE0(getpgrp) +{ + return sys_getpgid(0); +} + +#endif + +SYSCALL_DEFINE1(getsid, pid_t, pid) +{ + struct task_struct *p; + struct pid *sid; + int retval; + + rcu_read_lock(); + if (!pid) + sid = task_session(current); + else { + retval = -ESRCH; + p = find_task_by_vpid(pid); + if (!p) + goto out; + sid = task_session(p); + if (!sid) + goto out; + + retval = security_task_getsid(p); + if (retval) + goto out; + } + retval = pid_vnr(sid); +out: + rcu_read_unlock(); + return retval; +} + +SYSCALL_DEFINE0(setsid) +{ + struct task_struct *group_leader = current->group_leader; + struct pid *sid = task_pid(group_leader); + pid_t session = pid_vnr(sid); + int err = -EPERM; + + write_lock_irq(&tasklist_lock); + /* Fail if I am already a session leader */ + if (group_leader->signal->leader) + goto out; + + /* Fail if a process group id already exists that equals the + * proposed session id. + */ + if (pid_task(sid, PIDTYPE_PGID)) + goto out; + + group_leader->signal->leader = 1; + __set_special_pids(sid); + + proc_clear_tty(group_leader); + + err = session; +out: + write_unlock_irq(&tasklist_lock); + if (err > 0) { + proc_sid_connector(group_leader); + sched_autogroup_create_attach(group_leader); + } + return err; +} + +DECLARE_RWSEM(uts_sem); + +#ifdef COMPAT_UTS_MACHINE +#define override_architecture(name) \ + (personality(current->personality) == PER_LINUX32 && \ + copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ + sizeof(COMPAT_UTS_MACHINE))) +#else +#define override_architecture(name) 0 +#endif + +/* + * Work around broken programs that cannot handle "Linux 3.0". + * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 + */ +static int override_release(char __user *release, int len) +{ + int ret = 0; + char buf[65]; + + if (current->personality & UNAME26) { + char *rest = UTS_RELEASE; + int ndots = 0; + unsigned v; + + while (*rest) { + if (*rest == '.' && ++ndots >= 3) + break; + if (!isdigit(*rest) && *rest != '.') + break; + rest++; + } + v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40; + snprintf(buf, len, "2.6.%u%s", v, rest); + ret = copy_to_user(release, buf, len); + } + return ret; +} + +SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) +{ + int errno = 0; + + down_read(&uts_sem); + if (copy_to_user(name, utsname(), sizeof *name)) + errno = -EFAULT; + up_read(&uts_sem); + + if (!errno && override_release(name->release, sizeof(name->release))) + errno = -EFAULT; + if (!errno && override_architecture(name)) + errno = -EFAULT; + return errno; +} + +#ifdef __ARCH_WANT_SYS_OLD_UNAME +/* + * Old cruft + */ +SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) +{ + int error = 0; + + if (!name) + return -EFAULT; + + down_read(&uts_sem); + if (copy_to_user(name, utsname(), sizeof(*name))) + error = -EFAULT; + up_read(&uts_sem); + + if (!error && override_release(name->release, sizeof(name->release))) + error = -EFAULT; + if (!error && override_architecture(name)) + error = -EFAULT; + return error; +} + +SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) +{ + int error; + + if (!name) + return -EFAULT; + if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname))) + return -EFAULT; + + down_read(&uts_sem); + error = __copy_to_user(&name->sysname, &utsname()->sysname, + __OLD_UTS_LEN); + error |= __put_user(0, name->sysname + __OLD_UTS_LEN); + error |= __copy_to_user(&name->nodename, &utsname()->nodename, + __OLD_UTS_LEN); + error |= __put_user(0, name->nodename + __OLD_UTS_LEN); + error |= __copy_to_user(&name->release, &utsname()->release, + __OLD_UTS_LEN); + error |= __put_user(0, name->release + __OLD_UTS_LEN); + error |= __copy_to_user(&name->version, &utsname()->version, + __OLD_UTS_LEN); + error |= __put_user(0, name->version + __OLD_UTS_LEN); + error |= __copy_to_user(&name->machine, &utsname()->machine, + __OLD_UTS_LEN); + error |= __put_user(0, name->machine + __OLD_UTS_LEN); + up_read(&uts_sem); + + if (!error && override_architecture(name)) + error = -EFAULT; + if (!error && override_release(name->release, sizeof(name->release))) + error = -EFAULT; + return error ? -EFAULT : 0; +} +#endif + +SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) +{ + int errno; + char tmp[__NEW_UTS_LEN]; + + if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + + if (len < 0 || len > __NEW_UTS_LEN) + return -EINVAL; + down_write(&uts_sem); + errno = -EFAULT; + if (!copy_from_user(tmp, name, len)) { + struct new_utsname *u = utsname(); + + memcpy(u->nodename, tmp, len); + memset(u->nodename + len, 0, sizeof(u->nodename) - len); + errno = 0; + } + uts_proc_notify(UTS_PROC_HOSTNAME); + up_write(&uts_sem); + return errno; +} + +#ifdef __ARCH_WANT_SYS_GETHOSTNAME + +SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) +{ + int i, errno; + struct new_utsname *u; + + if (len < 0) + return -EINVAL; + down_read(&uts_sem); + u = utsname(); + i = 1 + strlen(u->nodename); + if (i > len) + i = len; + errno = 0; + if (copy_to_user(name, u->nodename, i)) + errno = -EFAULT; + up_read(&uts_sem); + return errno; +} + +#endif + +/* + * Only setdomainname; getdomainname can be implemented by calling + * uname() + */ +SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) +{ + int errno; + char tmp[__NEW_UTS_LEN]; + + if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + if (len < 0 || len > __NEW_UTS_LEN) + return -EINVAL; + + down_write(&uts_sem); + errno = -EFAULT; + if (!copy_from_user(tmp, name, len)) { + struct new_utsname *u = utsname(); + + memcpy(u->domainname, tmp, len); + memset(u->domainname + len, 0, sizeof(u->domainname) - len); + errno = 0; + } + uts_proc_notify(UTS_PROC_DOMAINNAME); + up_write(&uts_sem); + return errno; +} + +SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) +{ + struct rlimit value; + int ret; + + ret = do_prlimit(current, resource, NULL, &value); + if (!ret) + ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; + + return ret; +} + +#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT + +/* + * Back compatibility for getrlimit. Needed for some apps. + */ + +SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, + struct rlimit __user *, rlim) +{ + struct rlimit x; + if (resource >= RLIM_NLIMITS) + return -EINVAL; + + task_lock(current->group_leader); + x = current->signal->rlim[resource]; + task_unlock(current->group_leader); + if (x.rlim_cur > 0x7FFFFFFF) + x.rlim_cur = 0x7FFFFFFF; + if (x.rlim_max > 0x7FFFFFFF) + x.rlim_max = 0x7FFFFFFF; + return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; +} + +#endif + +static inline bool rlim64_is_infinity(__u64 rlim64) +{ +#if BITS_PER_LONG < 64 + return rlim64 >= ULONG_MAX; +#else + return rlim64 == RLIM64_INFINITY; +#endif +} + +static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) +{ + if (rlim->rlim_cur == RLIM_INFINITY) + rlim64->rlim_cur = RLIM64_INFINITY; + else + rlim64->rlim_cur = rlim->rlim_cur; + if (rlim->rlim_max == RLIM_INFINITY) + rlim64->rlim_max = RLIM64_INFINITY; + else + rlim64->rlim_max = rlim->rlim_max; +} + +static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) +{ + if (rlim64_is_infinity(rlim64->rlim_cur)) + rlim->rlim_cur = RLIM_INFINITY; + else + rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; + if (rlim64_is_infinity(rlim64->rlim_max)) + rlim->rlim_max = RLIM_INFINITY; + else + rlim->rlim_max = (unsigned long)rlim64->rlim_max; +} + +/* make sure you are allowed to change @tsk limits before calling this */ +int do_prlimit(struct task_struct *tsk, unsigned int resource, + struct rlimit *new_rlim, struct rlimit *old_rlim) +{ + struct rlimit *rlim; + int retval = 0; + + if (resource >= RLIM_NLIMITS) + return -EINVAL; + if (new_rlim) { + if (new_rlim->rlim_cur > new_rlim->rlim_max) + return -EINVAL; + if (resource == RLIMIT_NOFILE && + new_rlim->rlim_max > sysctl_nr_open) + return -EPERM; + } + + /* protect tsk->signal and tsk->sighand from disappearing */ + read_lock(&tasklist_lock); + if (!tsk->sighand) { + retval = -ESRCH; + goto out; + } + + rlim = tsk->signal->rlim + resource; + task_lock(tsk->group_leader); + if (new_rlim) { + /* Keep the capable check against init_user_ns until + cgroups can contain all limits */ + if (new_rlim->rlim_max > rlim->rlim_max && + !capable(CAP_SYS_RESOURCE)) + retval = -EPERM; + if (!retval) + retval = security_task_setrlimit(tsk->group_leader, + resource, new_rlim); + if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) { + /* + * The caller is asking for an immediate RLIMIT_CPU + * expiry. But we use the zero value to mean "it was + * never set". So let's cheat and make it one second + * instead + */ + new_rlim->rlim_cur = 1; + } + } + if (!retval) { + if (old_rlim) + *old_rlim = *rlim; + if (new_rlim) + *rlim = *new_rlim; + } + task_unlock(tsk->group_leader); + + /* + * RLIMIT_CPU handling. Note that the kernel fails to return an error + * code if it rejected the user's attempt to set RLIMIT_CPU. This is a + * very long-standing error, and fixing it now risks breakage of + * applications, so we live with it + */ + if (!retval && new_rlim && resource == RLIMIT_CPU && + new_rlim->rlim_cur != RLIM_INFINITY) + update_rlimit_cpu(tsk, new_rlim->rlim_cur); +out: + read_unlock(&tasklist_lock); + return retval; +} + +/* rcu lock must be held */ +static int check_prlimit_permission(struct task_struct *task) +{ + const struct cred *cred = current_cred(), *tcred; + + if (current == task) + return 0; + + tcred = __task_cred(task); + if (cred->user->user_ns == tcred->user->user_ns && + (cred->uid == tcred->euid && + cred->uid == tcred->suid && + cred->uid == tcred->uid && + cred->gid == tcred->egid && + cred->gid == tcred->sgid && + cred->gid == tcred->gid)) + return 0; + if (ns_capable(tcred->user->user_ns, CAP_SYS_RESOURCE)) + return 0; + + return -EPERM; +} + +SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, + const struct rlimit64 __user *, new_rlim, + struct rlimit64 __user *, old_rlim) +{ + struct rlimit64 old64, new64; + struct rlimit old, new; + struct task_struct *tsk; + int ret; + + if (new_rlim) { + if (copy_from_user(&new64, new_rlim, sizeof(new64))) + return -EFAULT; + rlim64_to_rlim(&new64, &new); + } + + rcu_read_lock(); + tsk = pid ? find_task_by_vpid(pid) : current; + if (!tsk) { + rcu_read_unlock(); + return -ESRCH; + } + ret = check_prlimit_permission(tsk); + if (ret) { + rcu_read_unlock(); + return ret; + } + get_task_struct(tsk); + rcu_read_unlock(); + + ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, + old_rlim ? &old : NULL); + + if (!ret && old_rlim) { + rlim_to_rlim64(&old, &old64); + if (copy_to_user(old_rlim, &old64, sizeof(old64))) + ret = -EFAULT; + } + + put_task_struct(tsk); + return ret; +} + +SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) +{ + struct rlimit new_rlim; + + if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) + return -EFAULT; + return do_prlimit(current, resource, &new_rlim, NULL); +} + +/* + * It would make sense to put struct rusage in the task_struct, + * except that would make the task_struct be *really big*. After + * task_struct gets moved into malloc'ed memory, it would + * make sense to do this. It will make moving the rest of the information + * a lot simpler! (Which we're not doing right now because we're not + * measuring them yet). + * + * When sampling multiple threads for RUSAGE_SELF, under SMP we might have + * races with threads incrementing their own counters. But since word + * reads are atomic, we either get new values or old values and we don't + * care which for the sums. We always take the siglock to protect reading + * the c* fields from p->signal from races with exit.c updating those + * fields when reaping, so a sample either gets all the additions of a + * given child after it's reaped, or none so this sample is before reaping. + * + * Locking: + * We need to take the siglock for CHILDEREN, SELF and BOTH + * for the cases current multithreaded, non-current single threaded + * non-current multithreaded. Thread traversal is now safe with + * the siglock held. + * Strictly speaking, we donot need to take the siglock if we are current and + * single threaded, as no one else can take our signal_struct away, no one + * else can reap the children to update signal->c* counters, and no one else + * can race with the signal-> fields. If we do not take any lock, the + * signal-> fields could be read out of order while another thread was just + * exiting. So we should place a read memory barrier when we avoid the lock. + * On the writer side, write memory barrier is implied in __exit_signal + * as __exit_signal releases the siglock spinlock after updating the signal-> + * fields. But we don't do this yet to keep things simple. + * + */ + +static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) +{ + r->ru_nvcsw += t->nvcsw; + r->ru_nivcsw += t->nivcsw; + r->ru_minflt += t->min_flt; + r->ru_majflt += t->maj_flt; + r->ru_inblock += task_io_get_inblock(t); + r->ru_oublock += task_io_get_oublock(t); +} + +static void k_getrusage(struct task_struct *p, int who, struct rusage *r) +{ + struct task_struct *t; + unsigned long flags; + cputime_t tgutime, tgstime, utime, stime; + unsigned long maxrss = 0; + + memset((char *) r, 0, sizeof *r); + utime = stime = 0; + + if (who == RUSAGE_THREAD) { + task_times(current, &utime, &stime); + accumulate_thread_rusage(p, r); + maxrss = p->signal->maxrss; + goto out; + } + + if (!lock_task_sighand(p, &flags)) + return; + + switch (who) { + case RUSAGE_BOTH: + case RUSAGE_CHILDREN: + utime = p->signal->cutime; + stime = p->signal->cstime; + r->ru_nvcsw = p->signal->cnvcsw; + r->ru_nivcsw = p->signal->cnivcsw; + r->ru_minflt = p->signal->cmin_flt; + r->ru_majflt = p->signal->cmaj_flt; + r->ru_inblock = p->signal->cinblock; + r->ru_oublock = p->signal->coublock; + maxrss = p->signal->cmaxrss; + + if (who == RUSAGE_CHILDREN) + break; + + case RUSAGE_SELF: + thread_group_times(p, &tgutime, &tgstime); + utime += tgutime; + stime += tgstime; + r->ru_nvcsw += p->signal->nvcsw; + r->ru_nivcsw += p->signal->nivcsw; + r->ru_minflt += p->signal->min_flt; + r->ru_majflt += p->signal->maj_flt; + r->ru_inblock += p->signal->inblock; + r->ru_oublock += p->signal->oublock; + if (maxrss < p->signal->maxrss) + maxrss = p->signal->maxrss; + t = p; + do { + accumulate_thread_rusage(t, r); + t = next_thread(t); + } while (t != p); + break; + + default: + BUG(); + } + unlock_task_sighand(p, &flags); + +out: + cputime_to_timeval(utime, &r->ru_utime); + cputime_to_timeval(stime, &r->ru_stime); + + if (who != RUSAGE_CHILDREN) { + struct mm_struct *mm = get_task_mm(p); + if (mm) { + setmax_mm_hiwater_rss(&maxrss, mm); + mmput(mm); + } + } + r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ +} + +int getrusage(struct task_struct *p, int who, struct rusage __user *ru) +{ + struct rusage r; + k_getrusage(p, who, &r); + return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; +} + +SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) +{ + if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && + who != RUSAGE_THREAD) + return -EINVAL; + return getrusage(current, who, ru); +} + +SYSCALL_DEFINE1(umask, int, mask) +{ + mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); + return mask; +} + +#ifdef CONFIG_CHECKPOINT_RESTORE +static int prctl_set_mm(int opt, unsigned long addr, + unsigned long arg4, unsigned long arg5) +{ + unsigned long rlim = rlimit(RLIMIT_DATA); + unsigned long vm_req_flags; + unsigned long vm_bad_flags; + struct vm_area_struct *vma; + int error = 0; + struct mm_struct *mm = current->mm; + + if (arg4 | arg5) + return -EINVAL; + + if (!capable(CAP_SYS_RESOURCE)) + return -EPERM; + + if (addr >= TASK_SIZE) + return -EINVAL; + + down_read(&mm->mmap_sem); + vma = find_vma(mm, addr); + + if (opt != PR_SET_MM_START_BRK && opt != PR_SET_MM_BRK) { + /* It must be existing VMA */ + if (!vma || vma->vm_start > addr) + goto out; + } + + error = -EINVAL; + switch (opt) { + case PR_SET_MM_START_CODE: + case PR_SET_MM_END_CODE: + vm_req_flags = VM_READ | VM_EXEC; + vm_bad_flags = VM_WRITE | VM_MAYSHARE; + + if ((vma->vm_flags & vm_req_flags) != vm_req_flags || + (vma->vm_flags & vm_bad_flags)) + goto out; + + if (opt == PR_SET_MM_START_CODE) + mm->start_code = addr; + else + mm->end_code = addr; + break; + + case PR_SET_MM_START_DATA: + case PR_SET_MM_END_DATA: + vm_req_flags = VM_READ | VM_WRITE; + vm_bad_flags = VM_EXEC | VM_MAYSHARE; + + if ((vma->vm_flags & vm_req_flags) != vm_req_flags || + (vma->vm_flags & vm_bad_flags)) + goto out; + + if (opt == PR_SET_MM_START_DATA) + mm->start_data = addr; + else + mm->end_data = addr; + break; + + case PR_SET_MM_START_STACK: + +#ifdef CONFIG_STACK_GROWSUP + vm_req_flags = VM_READ | VM_WRITE | VM_GROWSUP; +#else + vm_req_flags = VM_READ | VM_WRITE | VM_GROWSDOWN; +#endif + if ((vma->vm_flags & vm_req_flags) != vm_req_flags) + goto out; + + mm->start_stack = addr; + break; + + case PR_SET_MM_START_BRK: + if (addr <= mm->end_data) + goto out; + + if (rlim < RLIM_INFINITY && + (mm->brk - addr) + + (mm->end_data - mm->start_data) > rlim) + goto out; + + mm->start_brk = addr; + break; + + case PR_SET_MM_BRK: + if (addr <= mm->end_data) + goto out; + + if (rlim < RLIM_INFINITY && + (addr - mm->start_brk) + + (mm->end_data - mm->start_data) > rlim) + goto out; + + mm->brk = addr; + break; + + default: + error = -EINVAL; + goto out; + } + + error = 0; + +out: + up_read(&mm->mmap_sem); + + return error; +} +#else /* CONFIG_CHECKPOINT_RESTORE */ +static int prctl_set_mm(int opt, unsigned long addr, + unsigned long arg4, unsigned long arg5) +{ + return -EINVAL; +} +#endif + +SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, + unsigned long, arg4, unsigned long, arg5) +{ + struct task_struct *me = current; + unsigned char comm[sizeof(me->comm)]; + long error; + + error = security_task_prctl(option, arg2, arg3, arg4, arg5); + if (error != -ENOSYS) + return error; + + error = 0; + switch (option) { + case PR_SET_PDEATHSIG: + if (!valid_signal(arg2)) { + error = -EINVAL; + break; + } + me->pdeath_signal = arg2; + error = 0; + break; + case PR_GET_PDEATHSIG: + error = put_user(me->pdeath_signal, (int __user *)arg2); + break; + case PR_GET_DUMPABLE: + error = get_dumpable(me->mm); + break; + case PR_SET_DUMPABLE: + if (arg2 < 0 || arg2 > 1) { + error = -EINVAL; + break; + } + set_dumpable(me->mm, arg2); + error = 0; + break; + + case PR_SET_UNALIGN: + error = SET_UNALIGN_CTL(me, arg2); + break; + case PR_GET_UNALIGN: + error = GET_UNALIGN_CTL(me, arg2); + break; + case PR_SET_FPEMU: + error = SET_FPEMU_CTL(me, arg2); + break; + case PR_GET_FPEMU: + error = GET_FPEMU_CTL(me, arg2); + break; + case PR_SET_FPEXC: + error = SET_FPEXC_CTL(me, arg2); + break; + case PR_GET_FPEXC: + error = GET_FPEXC_CTL(me, arg2); + break; + case PR_GET_TIMING: + error = PR_TIMING_STATISTICAL; + break; + case PR_SET_TIMING: + if (arg2 != PR_TIMING_STATISTICAL) + error = -EINVAL; + else + error = 0; + break; + + case PR_SET_NAME: + comm[sizeof(me->comm)-1] = 0; + if (strncpy_from_user(comm, (char __user *)arg2, + sizeof(me->comm) - 1) < 0) + return -EFAULT; + set_task_comm(me, comm); + proc_comm_connector(me); + return 0; + case PR_GET_NAME: + get_task_comm(comm, me); + if (copy_to_user((char __user *)arg2, comm, + sizeof(comm))) + return -EFAULT; + return 0; + case PR_GET_ENDIAN: + error = GET_ENDIAN(me, arg2); + break; + case PR_SET_ENDIAN: + error = SET_ENDIAN(me, arg2); + break; + + case PR_GET_SECCOMP: + error = prctl_get_seccomp(); + break; + case PR_SET_SECCOMP: + error = prctl_set_seccomp(arg2); + break; + case PR_GET_TSC: + error = GET_TSC_CTL(arg2); + break; + case PR_SET_TSC: + error = SET_TSC_CTL(arg2); + break; + case PR_TASK_PERF_EVENTS_DISABLE: + error = perf_event_task_disable(); + break; + case PR_TASK_PERF_EVENTS_ENABLE: + error = perf_event_task_enable(); + break; + case PR_GET_TIMERSLACK: + error = current->timer_slack_ns; + break; + case PR_SET_TIMERSLACK: + if (arg2 <= 0) + current->timer_slack_ns = + current->default_timer_slack_ns; + else + current->timer_slack_ns = arg2; + error = 0; + break; + case PR_MCE_KILL: + if (arg4 | arg5) + return -EINVAL; + switch (arg2) { + case PR_MCE_KILL_CLEAR: + if (arg3 != 0) + return -EINVAL; + current->flags &= ~PF_MCE_PROCESS; + break; + case PR_MCE_KILL_SET: + current->flags |= PF_MCE_PROCESS; + if (arg3 == PR_MCE_KILL_EARLY) + current->flags |= PF_MCE_EARLY; + else if (arg3 == PR_MCE_KILL_LATE) + current->flags &= ~PF_MCE_EARLY; + else if (arg3 == PR_MCE_KILL_DEFAULT) + current->flags &= + ~(PF_MCE_EARLY|PF_MCE_PROCESS); + else + return -EINVAL; + break; + default: + return -EINVAL; + } + error = 0; + break; + case PR_MCE_KILL_GET: + if (arg2 | arg3 | arg4 | arg5) + return -EINVAL; + if (current->flags & PF_MCE_PROCESS) + error = (current->flags & PF_MCE_EARLY) ? + PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; + else + error = PR_MCE_KILL_DEFAULT; + break; + case PR_SET_MM: + error = prctl_set_mm(arg2, arg3, arg4, arg5); + break; + case PR_SET_CHILD_SUBREAPER: + me->signal->is_child_subreaper = !!arg2; + error = 0; + break; + case PR_GET_CHILD_SUBREAPER: + error = put_user(me->signal->is_child_subreaper, + (int __user *) arg2); + break; + default: + error = -EINVAL; + break; + } + return error; +} + +SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, + struct getcpu_cache __user *, unused) +{ + int err = 0; + int cpu = raw_smp_processor_id(); + if (cpup) + err |= put_user(cpu, cpup); + if (nodep) + err |= put_user(cpu_to_node(cpu), nodep); + return err ? -EFAULT : 0; +} + +char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; + +static void argv_cleanup(struct subprocess_info *info) +{ + argv_free(info->argv); +} + +/** + * orderly_poweroff - Trigger an orderly system poweroff + * @force: force poweroff if command execution fails + * + * This may be called from any context to trigger a system shutdown. + * If the orderly shutdown fails, it will force an immediate shutdown. + */ +int orderly_poweroff(bool force) +{ + int argc; + char **argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc); + static char *envp[] = { + "HOME=/", + "PATH=/sbin:/bin:/usr/sbin:/usr/bin", + NULL + }; + int ret = -ENOMEM; + struct subprocess_info *info; + + if (argv == NULL) { + printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", + __func__, poweroff_cmd); + goto out; + } + + info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC); + if (info == NULL) { + argv_free(argv); + goto out; + } + + call_usermodehelper_setfns(info, NULL, argv_cleanup, NULL); + + ret = call_usermodehelper_exec(info, UMH_NO_WAIT); + + out: + if (ret && force) { + printk(KERN_WARNING "Failed to start orderly shutdown: " + "forcing the issue\n"); + + /* I guess this should try to kick off some daemon to + sync and poweroff asap. Or not even bother syncing + if we're doing an emergency shutdown? */ + emergency_sync(); + kernel_power_off(); + } + + return ret; +} +EXPORT_SYMBOL_GPL(orderly_poweroff); |