From 83690b82d228b3570565ebd0b41873933238b97f Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Tue, 4 Jun 2024 09:52:39 -0700 Subject: [PATCH] af_unix: Use skb_queue_empty_lockless() in unix_release_sock(). If the socket type is SOCK_STREAM or SOCK_SEQPACKET, unix_release_sock() checks the length of the peer socket's recvq under unix_state_lock(). However, unix_stream_read_generic() calls skb_unlink() after releasing the lock. Also, for SOCK_SEQPACKET, __skb_try_recv_datagram() unlinks skb without unix_state_lock(). Thues, unix_state_lock() does not protect qlen. Let's use skb_queue_empty_lockless() in unix_release_sock(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Signed-off-by: Paolo Abeni --- net/unix/af_unix.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index eb3ba3448ed3..80846279de9f 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -631,7 +631,7 @@ static void unix_release_sock(struct sock *sk, int embrion) unix_state_lock(skpair); /* No more writes */ WRITE_ONCE(skpair->sk_shutdown, SHUTDOWN_MASK); - if (!skb_queue_empty(&sk->sk_receive_queue) || embrion) + if (!skb_queue_empty_lockless(&sk->sk_receive_queue) || embrion) WRITE_ONCE(skpair->sk_err, ECONNRESET); unix_state_unlock(skpair); skpair->sk_state_change(skpair);