On Fri, Jan 10, 2025 at 09:35:07AM +0100, Stefano Garzarella wrote:
If the socket has been de-assigned or assigned to another transport, we must discard any packets received because they are not expected and would cause issues when we access vsk->transport.
A possible scenario is described by Hyunwoo Kim in the attached link, where after a first connect() interrupted by a signal, and a second connect() failed, we can find `vsk->transport` at NULL, leading to a NULL pointer dereference.
Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Cc: stable@vger.kernel.org Reported-by: Hyunwoo Kim v4bel@theori.io Reported-by: Wongi Lee qwerty@theori.io Closes: https://lore.kernel.org/netdev/Z2LvdTTQR7dBmPb5@v4bel-B760M-AORUS-ELITE-AX/ Signed-off-by: Stefano Garzarella sgarzare@redhat.com
net/vmw_vsock/virtio_transport_common.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 9acc13ab3f82..51a494b69be8 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1628,8 +1628,11 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, lock_sock(sk);
- /* Check if sk has been closed before lock_sock */
- if (sock_flag(sk, SOCK_DONE)) {
- /* Check if sk has been closed or assigned to another transport before
* lock_sock (note: listener sockets are not assigned to any transport)*/- if (sock_flag(sk, SOCK_DONE) ||
(sk->sk_state != TCP_LISTEN && vsk->transport != &t->transport)) {-- 2.47.1
Reviewed-by: Hyunwoo Kim v4bel@theori.io
Regards, Hyunwoo Kim