This is a note to let you know that I've just added the patch titled
vsock/virtio: Fix unsigned integer wrap around in virtio_transport_has_space()
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
vsock-virtio-fix-unsigned-integer-wrap-around-in-vir.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c31da294e92c36305029e0312db351bfda60f1c5
Author: Nikolay Kuratov <kniv@xxxxxxxxxxxxxx>
Date: Mon Dec 11 19:23:17 2023 +0300
vsock/virtio: Fix unsigned integer wrap around in virtio_transport_has_space()
[ Upstream commit 60316d7f10b17a7ebb1ead0642fee8710e1560e0 ]
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 <kniv@xxxxxxxxxxxxxx>
Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20231211162317.4116625-1-kniv@xxxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 449b5261e6610..187d0f7253a6f 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -348,7 +348,7 @@ 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;
