VSOCK: do not disconnect socket when peer has shutdown SEND only

[ Upstream commit dedc58e067d8c379a15a8a183c5db318201295bb ]

The peer may be expecting a reply having sent a request and then done a
shutdown(SHUT_WR), so tearing down the whole socket at this point seems
wrong and breaks for me with a client which does a SHUT_WR.

Looking at other socket family's stream_recvmsg callbacks doing a shutdown
here does not seem to be the norm and removing it does not seem to have
had any adverse effects that I can see.

I'm using Stefan's RFC virtio transport patches, I'm unsure of the impact
on the vmci transport.

Signed-off-by: Ian Campbell <ian.campbell@docker.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Cc: Andy King <acking@vmware.com>
Cc: Dmitry Torokhov <dtor@vmware.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Adit Ranadive <aditr@vmware.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 7fd1220fbfa0bb2477e2b7e6edcf714a5ae6a097..9b5bd6d142dc4c1daf0acacb3f8abbf3b805b275 100644 (file)
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1794,27 +1794,8 @@ vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
        else if (sk->sk_shutdown & RCV_SHUTDOWN)
                err = 0;
 
-       if (copied > 0) {
-               /* We only do these additional bookkeeping/notification steps
-                * if we actually copied something out of the queue pair
-                * instead of just peeking ahead.
-                */
-
-               if (!(flags & MSG_PEEK)) {
-                       /* If the other side has shutdown for sending and there
-                        * is nothing more to read, then modify the socket
-                        * state.
-                        */
-                       if (vsk->peer_shutdown & SEND_SHUTDOWN) {
-                               if (vsock_stream_has_data(vsk) <= 0) {
-                                       sk->sk_state = SS_UNCONNECTED;
-                                       sock_set_flag(sk, SOCK_DONE);
-                                       sk->sk_state_change(sk);
-                               }
-                       }
-               }
+       if (copied > 0)
                err = copied;
-       }
 
 out_wait:
        finish_wait(sk_sleep(sk), &wait);