From cddcc9959a32999ce2d38018900595a5ab453eb2 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 1 Oct 2018 23:24:26 -0700 Subject: tcp: do not release socket ownership in tcp_close() commit 8873c064d1de579ea23412a6d3eee972593f142b upstream. syzkaller was able to hit the WARN_ON(sock_owned_by_user(sk)); in tcp_close() While a socket is being closed, it is very possible other threads find it in rtnetlink dump. tcp_get_info() will acquire the socket lock for a short amount of time (slow = lock_sock_fast(sk)/unlock_sock_fast(sk, slow);), enough to trigger the warning. Fixes: 67db3e4bfbc9 ("tcp: no longer hold ehash lock while calling tcp_get_info()") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/sock.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/net/sock.h b/include/net/sock.h index c64a1cff9eb3..f18dbd6da906 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1491,6 +1491,7 @@ static inline void lock_sock(struct sock *sk) lock_sock_nested(sk, 0); } +void __release_sock(struct sock *sk); void release_sock(struct sock *sk); /* BH context may only use the following locking interface. */ -- cgit v1.2.3