cgroup: duplicate cgroup reference when cloning sockets
authorJohannes Weiner <jweiner@fb.com>
Mon, 19 Sep 2016 21:44:38 +0000 (14:44 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 19 Sep 2016 22:36:17 +0000 (15:36 -0700)
commitd979a39d7242e0601bf9b60e89628fb8ac577179
treef790aa92992c9bf54088de8d8bf0fa275252ab1f
parentdb2ba40c277dc545bab531671c3f45ac0afea6f8
cgroup: duplicate cgroup reference when cloning sockets

When a socket is cloned, the associated sock_cgroup_data is duplicated
but not its reference on the cgroup.  As a result, the cgroup reference
count will underflow when both sockets are destroyed later on.

Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup")
Link: http://lkml.kernel.org/r/20160914194846.11153-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: <stable@vger.kernel.org> [4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/cgroup.c
net/core/sock.c