Use find_task_by_vpid in posix timers
Pavel Emelyanov [Fri, 8 Feb 2008 12:21:52 +0000 (04:21 -0800)]
All the functions that need to lookup a task by pid in posix timers obtain
this pid from a user space, and thus this value refers to a task in the same
namespace, as the current task lives in.

So the proper behavior is to call find_task_by_vpid() here.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/posix-cpu-timers.c
kernel/posix-timers.c

index 0b7c82a..2eae91f 100644 (file)
@@ -20,7 +20,7 @@ static int check_clock(const clockid_t which_clock)
                return 0;
 
        read_lock(&tasklist_lock);
-       p = find_task_by_pid(pid);
+       p = find_task_by_vpid(pid);
        if (!p || !(CPUCLOCK_PERTHREAD(which_clock) ?
                   same_thread_group(p, current) : thread_group_leader(p))) {
                error = -EINVAL;
@@ -305,7 +305,7 @@ int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp)
                 */
                struct task_struct *p;
                rcu_read_lock();
-               p = find_task_by_pid(pid);
+               p = find_task_by_vpid(pid);
                if (p) {
                        if (CPUCLOCK_PERTHREAD(which_clock)) {
                                if (same_thread_group(p, current)) {
@@ -354,7 +354,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer)
                if (pid == 0) {
                        p = current;
                } else {
-                       p = find_task_by_pid(pid);
+                       p = find_task_by_vpid(pid);
                        if (p && !same_thread_group(p, current))
                                p = NULL;
                }
@@ -362,7 +362,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer)
                if (pid == 0) {
                        p = current->group_leader;
                } else {
-                       p = find_task_by_pid(pid);
+                       p = find_task_by_vpid(pid);
                        if (p && !thread_group_leader(p))
                                p = NULL;
                }
index 122d5c7..ce26896 100644 (file)
@@ -404,7 +404,7 @@ static struct task_struct * good_sigevent(sigevent_t * event)
        struct task_struct *rtn = current->group_leader;
 
        if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
-               (!(rtn = find_task_by_pid(event->sigev_notify_thread_id)) ||
+               (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
                 !same_thread_group(rtn, current) ||
                 (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
                return NULL;