[PATCH] posix-cpu-timers: Fix pid refcount leak in do_cpu_nanosleep() error path

[WenTao Liang]

In do_cpu_nanosleep(), posix_cpu_timer_create() takes a pid reference
via get_pid() and stores it in timer.it.cpu.pid. If the subsequent
posix_cpu_timer_set() call fails, the function returns immediately
without calling posix_cpu_timer_del() to release the pid reference,
causing a leak.

Fix it by calling posix_cpu_timer_del() before the unlock-and-return
on the error path, consistent with the other exit paths in the same
function.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: WenTao Liang <vulab@xxxxxxxxxxx>
---
 kernel/time/posix-cpu-timers.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 0de2bb7cbec0..6f3ddb2b1f46 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1504,6 +1504,7 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
 		spin_lock_irq(&timer.it_lock);
 		error = posix_cpu_timer_set(&timer, flags, &it, NULL);
 		if (error) {
+			posix_cpu_timer_del(&timer);
 			spin_unlock_irq(&timer.it_lock);
 			return error;
 		}
-- 
2.50.1 (Apple Git-155)