posix_cpu_timer: Exit early when process has been reaped

Variable "now" seems to be genuinely used unintialized
if branch

	if (CPUCLOCK_PERTHREAD(timer->it_clock)) {

is not taken and branch

	if (unlikely(sighand == NULL)) {

is taken. In this case the process has been reaped and the timer is marked as
disarmed anyway. So none of the postprocessing of the sample is
required. Return right away.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20160707223911.GA26483@p183.telecom.by
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 1cafba860b08ceb6030fa2a1f237e3950a4e0aa7..39008d78927acb4f9a62f582cb7baba3f27620ee 100644 (file)
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -777,6 +777,7 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp)
                        timer->it.cpu.expires = 0;
                        sample_to_timespec(timer->it_clock, timer->it.cpu.expires,
                                           &itp->it_value);
+                       return;
                } else {
                        cpu_timer_sample_group(timer->it_clock, p, &now);
                        unlock_task_sighand(p, &flags);