Commit 91751e24 authored by Stefano Garzarella's avatar Stefano Garzarella Committed by Paolo Abeni
Browse files

vsock: prevent null-ptr-deref in vsock_*[has_data|has_space] 

Recent reports have shown how we sometimes call vsock_*_has_data()
when a vsock socket has been de-assigned from a transport (see attached
links), but we shouldn't.

Previous commits should have solved the real problems, but we may have
more in the future, so to avoid null-ptr-deref, we can return 0
(no space, no data available) but with a warning.

This way the code should continue to run in a nearly consistent state
and have a warning that allows us to debug future problems.

Fixes: c0cfa2d8 ("vsock: add multi-transports support")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/netdev/Z2K%2FI4nlHdfMRTZC@v4bel-B760M-AORUS-ELITE-AX/
Link: https://lore.kernel.org/netdev/5ca20d4c-1017-49c2-9516-f6f75fd331e9@rbox.co/
Link: https://lore.kernel.org/netdev/677f84a8.050a0220.25a300.01b3.GAE@google.com/


Co-developed-by: default avatarHyunwoo Kim <v4bel@theori.io>
Signed-off-by: default avatarHyunwoo Kim <v4bel@theori.io>
Co-developed-by: default avatarWongi Lee <qwerty@theori.io>
Signed-off-by: default avatarWongi Lee <qwerty@theori.io>
Signed-off-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Reviewed-by: default avatarLuigi Leonardi <leonardi@redhat.com>
Reviewed-by: default avatarHyunwoo Kim <v4bel@theori.io>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent a24009bc

net/vmw_vsock/af_vsock.c

+9 −0
Original line number Diff line number Diff line
@@ -879,6 +879,9 @@ EXPORT_SYMBOL_GPL(vsock_create_connected); 


s64 vsock_stream_has_data(struct vsock_sock *vsk)

{

	if (WARN_ON(!vsk->transport))

		return 0;



	return vsk->transport->stream_has_data(vsk);

}

EXPORT_SYMBOL_GPL(vsock_stream_has_data);
@@ -887,6 +890,9 @@ s64 vsock_connectible_has_data(struct vsock_sock *vsk) 
{

	struct sock *sk = sk_vsock(vsk);



	if (WARN_ON(!vsk->transport))

		return 0;



	if (sk->sk_type == SOCK_SEQPACKET)

		return vsk->transport->seqpacket_has_data(vsk);

	else
@@ -896,6 +902,9 @@ EXPORT_SYMBOL_GPL(vsock_connectible_has_data); 


s64 vsock_stream_has_space(struct vsock_sock *vsk)

{

	if (WARN_ON(!vsk->transport))

		return 0;



	return vsk->transport->stream_has_space(vsk);

}

EXPORT_SYMBOL_GPL(vsock_stream_has_space);