From 1da06ea85c6fba572d21b8985549807235fb23a3 Mon Sep 17 00:00:00 2001 From: Jiang Wang Date: Mon, 4 Oct 2021 23:25:28 +0000 Subject: [PATCH] unix: Fix an issue in unix_shutdown causing the other end read/write failures Commit d4a1875ddd1e ("af_unix: Add unix_stream_proto for sockmap") sets unix domain socket peer state to TCP_CLOSE in unix_shutdown. This could happen when the local end is shutdown but the other end is not. Then, the other end will get read or write failures which is not expected. Fix the issue by setting the local state to shutdown. Fixes: d4a1875ddd1e ("af_unix: Add unix_stream_proto for sockmap") Reported-by: Casey Schaufler Suggested-by: Cong Wang Signed-off-by: Jiang Wang Signed-off-by: Daniel Borkmann Tested-by: Casey Schaufler Reviewed-by: Casey Schaufler Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20211004232530.2377085-1-jiang.wang@bytedance.com --- net/unix/af_unix.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index f505b89bda6ad..915afcae6a121 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -2860,6 +2860,9 @@ static int unix_shutdown(struct socket *sock, int mode) unix_state_lock(sk); sk->sk_shutdown |= mode; + if ((sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) && + mode == SHUTDOWN_MASK) + sk->sk_state = TCP_CLOSE; other = unix_peer(sk); if (other) sock_hold(other); @@ -2882,12 +2885,10 @@ static int unix_shutdown(struct socket *sock, int mode) other->sk_shutdown |= peer_mode; unix_state_unlock(other); other->sk_state_change(other); - if (peer_mode == SHUTDOWN_MASK) { + if (peer_mode == SHUTDOWN_MASK) sk_wake_async(other, SOCK_WAKE_WAITD, POLL_HUP); - other->sk_state = TCP_CLOSE; - } else if (peer_mode & RCV_SHUTDOWN) { + else if (peer_mode & RCV_SHUTDOWN) sk_wake_async(other, SOCK_WAKE_WAITD, POLL_IN); - } } if (other) sock_put(other); -- 2.39.5