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Diffstat (limited to 'kernel/sys.c')
-rw-r--r--kernel/sys.c275
1 files changed, 244 insertions, 31 deletions
diff --git a/kernel/sys.c b/kernel/sys.c
index fd2b5259ad7a..b95d3c72ba21 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -49,6 +49,11 @@
#include <linux/user_namespace.h>
#include <linux/binfmts.h>
+#include <linux/sched.h>
+#include <linux/rcupdate.h>
+#include <linux/uidgid.h>
+#include <linux/cred.h>
+
#include <linux/kmsg_dump.h>
/* Move somewhere else to avoid recompiling? */
#include <generated/utsrelease.h>
@@ -324,7 +329,6 @@ void kernel_restart_prepare(char *cmd)
system_state = SYSTEM_RESTART;
usermodehelper_disable();
device_shutdown();
- syscore_shutdown();
}
/**
@@ -370,6 +374,7 @@ void kernel_restart(char *cmd)
{
kernel_restart_prepare(cmd);
disable_nonboot_cpus();
+ syscore_shutdown();
if (!cmd)
printk(KERN_EMERG "Restarting system.\n");
else
@@ -395,6 +400,7 @@ static void kernel_shutdown_prepare(enum system_states state)
void kernel_halt(void)
{
kernel_shutdown_prepare(SYSTEM_HALT);
+ disable_nonboot_cpus();
syscore_shutdown();
printk(KERN_EMERG "System halted.\n");
kmsg_dump(KMSG_DUMP_HALT);
@@ -1043,6 +1049,67 @@ change_okay:
return old_fsgid;
}
+/**
+ * sys_getpid - return the thread group id of the current process
+ *
+ * Note, despite the name, this returns the tgid not the pid. The tgid and
+ * the pid are identical unless CLONE_THREAD was specified on clone() in
+ * which case the tgid is the same in all threads of the same group.
+ *
+ * This is SMP safe as current->tgid does not change.
+ */
+SYSCALL_DEFINE0(getpid)
+{
+ return task_tgid_vnr(current);
+}
+
+/* Thread ID - the internal kernel "pid" */
+SYSCALL_DEFINE0(gettid)
+{
+ return task_pid_vnr(current);
+}
+
+/*
+ * Accessing ->real_parent is not SMP-safe, it could
+ * change from under us. However, we can use a stale
+ * value of ->real_parent under rcu_read_lock(), see
+ * release_task()->call_rcu(delayed_put_task_struct).
+ */
+SYSCALL_DEFINE0(getppid)
+{
+ int pid;
+
+ rcu_read_lock();
+ pid = task_tgid_vnr(rcu_dereference(current->real_parent));
+ rcu_read_unlock();
+
+ return pid;
+}
+
+SYSCALL_DEFINE0(getuid)
+{
+ /* Only we change this so SMP safe */
+ return from_kuid_munged(current_user_ns(), current_uid());
+}
+
+SYSCALL_DEFINE0(geteuid)
+{
+ /* Only we change this so SMP safe */
+ return from_kuid_munged(current_user_ns(), current_euid());
+}
+
+SYSCALL_DEFINE0(getgid)
+{
+ /* Only we change this so SMP safe */
+ return from_kgid_munged(current_user_ns(), current_gid());
+}
+
+SYSCALL_DEFINE0(getegid)
+{
+ /* Only we change this so SMP safe */
+ return from_kgid_munged(current_user_ns(), current_egid());
+}
+
void do_sys_times(struct tms *tms)
{
cputime_t tgutime, tgstime, cutime, cstime;
@@ -1804,7 +1871,6 @@ SYSCALL_DEFINE1(umask, int, mask)
return mask;
}
-#ifdef CONFIG_CHECKPOINT_RESTORE
static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
{
struct fd exe;
@@ -1998,17 +2064,12 @@ out:
return error;
}
+#ifdef CONFIG_CHECKPOINT_RESTORE
static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
{
return put_user(me->clear_child_tid, tid_addr);
}
-
-#else /* CONFIG_CHECKPOINT_RESTORE */
-static int prctl_set_mm(int opt, unsigned long addr,
- unsigned long arg4, unsigned long arg5)
-{
- return -EINVAL;
-}
+#else
static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
{
return -EINVAL;
@@ -2199,9 +2260,8 @@ SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep,
char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff";
-static int __orderly_poweroff(void)
+static int __orderly_poweroff(bool force)
{
- int argc;
char **argv;
static char *envp[] = {
"HOME=/",
@@ -2210,20 +2270,40 @@ static int __orderly_poweroff(void)
};
int ret;
- argv = argv_split(GFP_ATOMIC, poweroff_cmd, &argc);
- if (argv == NULL) {
+ argv = argv_split(GFP_KERNEL, poweroff_cmd, NULL);
+ if (argv) {
+ ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
+ argv_free(argv);
+ } else {
printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n",
- __func__, poweroff_cmd);
- return -ENOMEM;
+ __func__, poweroff_cmd);
+ ret = -ENOMEM;
}
- ret = call_usermodehelper_fns(argv[0], argv, envp, UMH_WAIT_EXEC,
- NULL, NULL, NULL);
- argv_free(argv);
+ 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;
}
+static bool poweroff_force;
+
+static void poweroff_work_func(struct work_struct *work)
+{
+ __orderly_poweroff(poweroff_force);
+}
+
+static DECLARE_WORK(poweroff_work, poweroff_work_func);
+
/**
* orderly_poweroff - Trigger an orderly system poweroff
* @force: force poweroff if command execution fails
@@ -2233,21 +2313,154 @@ static int __orderly_poweroff(void)
*/
int orderly_poweroff(bool force)
{
- int ret = __orderly_poweroff();
+ if (force) /* do not override the pending "true" */
+ poweroff_force = true;
+ schedule_work(&poweroff_work);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(orderly_poweroff);
- if (ret && force) {
- printk(KERN_WARNING "Failed to start orderly shutdown: "
- "forcing the issue\n");
+/**
+ * do_sysinfo - fill in sysinfo struct
+ * @info: pointer to buffer to fill
+ */
+static int do_sysinfo(struct sysinfo *info)
+{
+ unsigned long mem_total, sav_total;
+ unsigned int mem_unit, bitcount;
+ struct timespec tp;
- /*
- * 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();
+ memset(info, 0, sizeof(struct sysinfo));
+
+ ktime_get_ts(&tp);
+ monotonic_to_bootbased(&tp);
+ info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
+
+ get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
+
+ info->procs = nr_threads;
+
+ si_meminfo(info);
+ si_swapinfo(info);
+
+ /*
+ * If the sum of all the available memory (i.e. ram + swap)
+ * is less than can be stored in a 32 bit unsigned long then
+ * we can be binary compatible with 2.2.x kernels. If not,
+ * well, in that case 2.2.x was broken anyways...
+ *
+ * -Erik Andersen <andersee@debian.org>
+ */
+
+ mem_total = info->totalram + info->totalswap;
+ if (mem_total < info->totalram || mem_total < info->totalswap)
+ goto out;
+ bitcount = 0;
+ mem_unit = info->mem_unit;
+ while (mem_unit > 1) {
+ bitcount++;
+ mem_unit >>= 1;
+ sav_total = mem_total;
+ mem_total <<= 1;
+ if (mem_total < sav_total)
+ goto out;
}
- return ret;
+ /*
+ * If mem_total did not overflow, multiply all memory values by
+ * info->mem_unit and set it to 1. This leaves things compatible
+ * with 2.2.x, and also retains compatibility with earlier 2.4.x
+ * kernels...
+ */
+
+ info->mem_unit = 1;
+ info->totalram <<= bitcount;
+ info->freeram <<= bitcount;
+ info->sharedram <<= bitcount;
+ info->bufferram <<= bitcount;
+ info->totalswap <<= bitcount;
+ info->freeswap <<= bitcount;
+ info->totalhigh <<= bitcount;
+ info->freehigh <<= bitcount;
+
+out:
+ return 0;
}
-EXPORT_SYMBOL_GPL(orderly_poweroff);
+
+SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
+{
+ struct sysinfo val;
+
+ do_sysinfo(&val);
+
+ if (copy_to_user(info, &val, sizeof(struct sysinfo)))
+ return -EFAULT;
+
+ return 0;
+}
+
+#ifdef CONFIG_COMPAT
+struct compat_sysinfo {
+ s32 uptime;
+ u32 loads[3];
+ u32 totalram;
+ u32 freeram;
+ u32 sharedram;
+ u32 bufferram;
+ u32 totalswap;
+ u32 freeswap;
+ u16 procs;
+ u16 pad;
+ u32 totalhigh;
+ u32 freehigh;
+ u32 mem_unit;
+ char _f[20-2*sizeof(u32)-sizeof(int)];
+};
+
+COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
+{
+ struct sysinfo s;
+
+ do_sysinfo(&s);
+
+ /* Check to see if any memory value is too large for 32-bit and scale
+ * down if needed
+ */
+ if ((s.totalram >> 32) || (s.totalswap >> 32)) {
+ int bitcount = 0;
+
+ while (s.mem_unit < PAGE_SIZE) {
+ s.mem_unit <<= 1;
+ bitcount++;
+ }
+
+ s.totalram >>= bitcount;
+ s.freeram >>= bitcount;
+ s.sharedram >>= bitcount;
+ s.bufferram >>= bitcount;
+ s.totalswap >>= bitcount;
+ s.freeswap >>= bitcount;
+ s.totalhigh >>= bitcount;
+ s.freehigh >>= bitcount;
+ }
+
+ if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
+ __put_user(s.uptime, &info->uptime) ||
+ __put_user(s.loads[0], &info->loads[0]) ||
+ __put_user(s.loads[1], &info->loads[1]) ||
+ __put_user(s.loads[2], &info->loads[2]) ||
+ __put_user(s.totalram, &info->totalram) ||
+ __put_user(s.freeram, &info->freeram) ||
+ __put_user(s.sharedram, &info->sharedram) ||
+ __put_user(s.bufferram, &info->bufferram) ||
+ __put_user(s.totalswap, &info->totalswap) ||
+ __put_user(s.freeswap, &info->freeswap) ||
+ __put_user(s.procs, &info->procs) ||
+ __put_user(s.totalhigh, &info->totalhigh) ||
+ __put_user(s.freehigh, &info->freehigh) ||
+ __put_user(s.mem_unit, &info->mem_unit))
+ return -EFAULT;
+
+ return 0;
+}
+#endif /* CONFIG_COMPAT */