This is a note to let you know that I've just added the patch titled vsock: notify server to shutdown when client has pending signal to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: vsock-notify-server-to-shutdown-when-client-has-pend.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f44ec38312423f0cfc3c1170419d6f6d316fe1db Author: Longpeng(Mike) <longpeng2@xxxxxxxxxx> Date: Mon Jun 21 14:26:01 2021 +0800 vsock: notify server to shutdown when client has pending signal [ Upstream commit c7ff9cff70601ea19245d997bb977344663434c7 ] The client's sk_state will be set to TCP_ESTABLISHED if the server replay the client's connect request. However, if the client has pending signal, its sk_state will be set to TCP_CLOSE without notify the server, so the server will hold the corrupt connection. client server 1. sk_state=TCP_SYN_SENT | 2. call ->connect() | 3. wait reply | | 4. sk_state=TCP_ESTABLISHED | 5. insert to connected list | 6. reply to the client 7. sk_state=TCP_ESTABLISHED | 8. insert to connected list | 9. *signal pending* <--------------------- the user kill client 10. sk_state=TCP_CLOSE | client is exiting... | 11. call ->release() | virtio_transport_close if (!(sk->sk_state == TCP_ESTABLISHED || sk->sk_state == TCP_CLOSING)) return true; *return at here, the server cannot notice the connection is corrupt* So the client should notify the peer in this case. Cc: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Jakub Kicinski <kuba@xxxxxxxxxx> Cc: Jorgen Hansen <jhansen@xxxxxxxxxx> Cc: Norbert Slusarek <nslusarek@xxxxxxx> Cc: Andra Paraschiv <andraprs@xxxxxxxxxx> Cc: Colin Ian King <colin.king@xxxxxxxxxxxxx> Cc: David Brazdil <dbrazdil@xxxxxxxxxx> Cc: Alexander Popov <alex.popov@xxxxxxxxx> Suggested-by: Stefano Garzarella <sgarzare@xxxxxxxxxx> Link: https://lkml.org/lkml/2021/5/17/418 Signed-off-by: lixianming <lixianming5@xxxxxxxxxx> Signed-off-by: Longpeng(Mike) <longpeng2@xxxxxxxxxx> Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index c82e7b52ab1f..d4104144bab1 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1217,7 +1217,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr, if (signal_pending(current)) { err = sock_intr_errno(timeout); - sk->sk_state = TCP_CLOSE; + sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; sock->state = SS_UNCONNECTED; vsock_transport_cancel_pkt(vsk); goto out_wait;