4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit c0576e3975084d4699b7bfef578613fb8e1144f6 ]
If for some reason, the newly allocated child need to be freed,
we will call cgroup_put() (via sk_free_unlock_clone()) while the
corresponding cgroup_get() was not yet done, and we will free memory
too soon.
Fixes: d979a39d7242 ("cgroup: duplicate cgroup reference when cloning sockets")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/core/sock.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1526,6 +1526,7 @@ struct sock *sk_clone_lock(const struct
newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
sock_reset_flag(newsk, SOCK_DONE);
+ cgroup_sk_alloc(&newsk->sk_cgrp_data);
skb_queue_head_init(&newsk->sk_error_queue);
filter = rcu_dereference_protected(newsk->sk_filter, 1);
@@ -1560,8 +1561,6 @@ struct sock *sk_clone_lock(const struct
atomic64_set(&newsk->sk_cookie, 0);
mem_cgroup_sk_alloc(newsk);
- cgroup_sk_alloc(&newsk->sk_cgrp_data);
-
/*
* Before updating sk_refcnt, we must commit prior changes to memory
* (Documentation/RCU/rculist_nulls.txt for details)