From: Nikolay Kuratov Date: Mon, 11 Dec 2023 16:23:17 +0000 (+0300) Subject: vsock/virtio: Fix unsigned integer wrap around in virtio_transport_has_space() X-Git-Tag: v6.7-rc6~21^2~7 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=60316d7f10b17a7ebb1ead0642fee8710e1560e0;p=linux-2.6-block.git vsock/virtio: Fix unsigned integer wrap around in virtio_transport_has_space() We need to do signed arithmetic if we expect condition `if (bytes < 0)` to be possible Found by Linux Verification Center (linuxtesting.org) with SVACE Fixes: 06a8fc78367d ("VSOCK: Introduce virtio_vsock_common.ko") Signed-off-by: Nikolay Kuratov Reviewed-by: Stefano Garzarella Link: https://lore.kernel.org/r/20231211162317.4116625-1-kniv@yandex-team.ru Signed-off-by: Jakub Kicinski --- diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index c8e162c9d1df..6df246b53260 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -843,7 +843,7 @@ static s64 virtio_transport_has_space(struct vsock_sock *vsk) struct virtio_vsock_sock *vvs = vsk->trans; s64 bytes; - bytes = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt); + bytes = (s64)vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt); if (bytes < 0) bytes = 0;