prctl: make PR_SET_TIMERSLACK_PID pid namespace aware
Make PR_SET_TIMERSLACK_PID consider pid namespace and resolve the
target pid in the caller's namespace. Otherwise, calls from pid
namespace other than init would fail or affect the wrong task.
Change-Id: I1da15196abc4096536713ce03714e99d2e63820a
Signed-off-by: Micha Kalfon <micha@cellrox.com>
Acked-by: Oren Laadan <orenl@cellrox.com>
diff --git a/kernel/sys.c b/kernel/sys.c
index f2f766a..f66703e 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2223,11 +2223,11 @@
error = prctl_get_tid_address(me, (int __user **)arg2);
break;
case PR_SET_TIMERSLACK_PID:
- if (current->pid != (pid_t)arg3 &&
+ if (task_pid_vnr(current) != (pid_t)arg3 &&
!capable(CAP_SYS_NICE))
return -EPERM;
rcu_read_lock();
- tsk = find_task_by_pid_ns((pid_t)arg3, &init_pid_ns);
+ tsk = find_task_by_vpid((pid_t)arg3);
if (tsk == NULL) {
rcu_read_unlock();
return -EINVAL;