4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <[email protected]>


[ 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 <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Tejun Heo <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 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)


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