The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025012004-rise-cavity-58aa@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella sgarzare@redhat.com Date: Fri, 10 Jan 2025 09:35:07 +0100 Subject: [PATCH] vsock/virtio: discard packets if the transport changes
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 Reviewed-by: Hyunwoo Kim v4bel@theori.io Signed-off-by: Paolo Abeni pabeni@redhat.com
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)) { (void)virtio_transport_reset_no_sock(t, skb); release_sock(sk); sock_put(sk);