From: Eric W. Biederman <ebiederm@xmission.com>
Date: Thu, 13 Apr 2017 15:32:16 +0000 (-0500)
Subject: posix-timers: Correct sanity check in posix_cpu_nsleep
X-Git-Tag: v4.14-rc1~990^2~6
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=01a2197485a9917216ad67ced4bafed9f7942f5a;p=platform%2Fkernel%2Flinux-rpi.git

posix-timers: Correct sanity check in posix_cpu_nsleep

CPUCLOCK_PID(which_clock) is a pid value from userspace so compare it
against task_pid_vnr, not current->pid.  As task_pid_vnr is in the tasks
pid value in the tasks pid namespace, and current->pid is in the
initial pid namespace.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---

diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 4513ad1..37f9bb8 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1312,7 +1312,7 @@ static int posix_cpu_nsleep(const clockid_t which_clock, int flags,
 	 */
 	if (CPUCLOCK_PERTHREAD(which_clock) &&
 	    (CPUCLOCK_PID(which_clock) == 0 ||
-	     CPUCLOCK_PID(which_clock) == current->pid))
+	     CPUCLOCK_PID(which_clock) == task_pid_vnr(current)))
 		return -EINVAL;
 
 	error = do_cpu_nanosleep(which_clock, flags, rqtp, &it);