From 3d0bc44d39bca615b72637e340317b7899b7f911 Mon Sep 17 00:00:00 2001 From: Norbert Slusarek Date: Fri, 5 Feb 2021 13:14:05 +0100 Subject: net/vmw_vsock: improve locking in vsock_connect_timeout() A possible locking issue in vsock_connect_timeout() was recognized by Eric Dumazet which might cause a null pointer dereference in vsock_transport_cancel_pkt(). This patch assures that vsock_transport_cancel_pkt() will be called within the lock, so a race condition won't occur which could result in vsk->transport to be set to NULL. Fixes: 380feae0def7 ("vsock: cancel packets when failing to connect") Reported-by: Eric Dumazet Signed-off-by: Norbert Slusarek Reviewed-by: Stefano Garzarella Link: https://lore.kernel.org/r/trinity-f8e0937a-cf0e-4d80-a76e-d9a958ba3ef1-1612535522360@3c-app-gmx-bap12 Signed-off-by: Jakub Kicinski --- net/vmw_vsock/af_vsock.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'net/vmw_vsock') diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index cb81cfb47a78..4ea301fc2bf0 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1243,7 +1243,6 @@ static void vsock_connect_timeout(struct work_struct *work) { struct sock *sk; struct vsock_sock *vsk; - int cancel = 0; vsk = container_of(work, struct vsock_sock, connect_work.work); sk = sk_vsock(vsk); @@ -1254,11 +1253,9 @@ static void vsock_connect_timeout(struct work_struct *work) sk->sk_state = TCP_CLOSE; sk->sk_err = ETIMEDOUT; sk->sk_error_report(sk); - cancel = 1; + vsock_transport_cancel_pkt(vsk); } release_sock(sk); - if (cancel) - vsock_transport_cancel_pkt(vsk); sock_put(sk); } -- cgit