exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting
authorOleg Nesterov <oleg@redhat.com>
Wed, 10 Dec 2014 23:55:25 +0000 (15:55 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 11 Dec 2014 01:41:18 +0000 (17:41 -0800)
alloc_pid() does get_pid_ns() beforehand but forgets to put_pid_ns() if it
fails because disable_pid_allocation() was called by the exiting
child_reaper.

We could simply move get_pid_ns() down to successful return, but this fix
tries to be as trivial as possible.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Sterling Alexander <stalexan@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/pid.c

index 9b9a26698144e126486e162955e49561514b1ce8..82430c858d6970317cd71a3770cce9f723673b22 100644 (file)
@@ -341,6 +341,8 @@ out:
 
 out_unlock:
        spin_unlock_irq(&pidmap_lock);
+       put_pid_ns(ns);
+
 out_free:
        while (++i <= ns->level)
                free_pidmap(pid->numbers + i);