Commit 71abb94f authored by Andrea Parri (Microsoft)'s avatar Andrea Parri (Microsoft) Committed by Wei Liu
Browse files

hv_sock: Check hv_pkt_iter_first_raw()'s return value 



The function returns NULL if the ring buffer doesn't contain enough
readable bytes to constitute a packet descriptor.  The ring buffer's
write_index is in memory which is shared with the Hyper-V host, an
erroneous or malicious host could thus change its value and overturn
the result of hvs_stream_has_data().

Signed-off-by: default avatarAndrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: default avatarMichael Kelley <mikelley@microsoft.com>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20220428145107.7878-2-parri.andrea@gmail.com


Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
parent a765ed47

net/vmw_vsock/hyperv_transport.c

+2 −0
Original line number Diff line number Diff line
@@ -603,6 +603,8 @@ static ssize_t hvs_stream_dequeue(struct vsock_sock *vsk, struct msghdr *msg, 


	if (need_refill) {

		hvs->recv_desc = hv_pkt_iter_first_raw(hvs->chan);

		if (!hvs->recv_desc)

			return -ENOBUFS;

		ret = hvs_update_recv_data(hvs);

		if (ret)

			return ret;