@@ -1579,7 +1579,15 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
if (signal_pending(current)) {
err = sock_intr_errno(timeout);
- sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE;
+ if (sk->sk_state == TCP_ESTABLISHED) {
+ /* Might have raced with a sockmap update. */
+ if (sk->sk_prot->unhash)
+ sk->sk_prot->unhash(sk);
+
+ sk->sk_state = TCP_CLOSING;
+ } else {
+ sk->sk_state = TCP_CLOSE;
+ }
sock->state = SS_UNCONNECTED;
vsock_transport_cancel_pkt(vsk);
vsock_remove_connected(vsk);
@@ -127,6 +127,7 @@ static void vsock_bpf_rebuild_protos(struct proto *prot, const struct proto *bas
{
*prot = *base;
prot->close = sock_map_close;
+ prot->unhash = sock_map_unhash;
prot->recvmsg = vsock_bpf_recvmsg;
prot->sock_is_readable = sk_msg_is_readable;
}
Signal delivery during connect() may result in a disconnect of an already TCP_ESTABLISHED socket. Problem is that such established socket might have been placed in a sockmap before the connection was closed. We end up with a SS_UNCONNECTED vsock in a sockmap. And this, combined with the ability to reassign (unconnected) vsock's transport to NULL, breaks the sockmap contract. As manifested by WARN_ON_ONCE. connect / state = SS_CONNECTED / sock_map_update_elem if signal_pending state = SS_UNCONNECTED connect transport = NULL vsock_bpf_recvmsg WARN_ON_ONCE(!vsk->transport) Ensure the socket does not stay in sockmap. WARNING: CPU: 8 PID: 1228 at net/vmw_vsock/vsock_bpf.c:97 vsock_bpf_recvmsg+0xb43/0xe00 CPU: 8 UID: 0 PID: 1228 Comm: a.out Not tainted 6.14.0-rc5+ RIP: 0010:vsock_bpf_recvmsg+0xb43/0xe00 sock_recvmsg+0x1b2/0x220 __sys_recvfrom+0x190/0x270 __x64_sys_recvfrom+0xdc/0x1b0 do_syscall_64+0x93/0x1b0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Fixes: 634f1a7110b4 ("vsock: support sockmap") Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Michal Luczaj <mhal@rbox.co> --- net/vmw_vsock/af_vsock.c | 10 +++++++++- net/vmw_vsock/vsock_bpf.c | 1 + 2 files changed, 10 insertions(+), 1 deletion(-)