From 4a815de7d390494d8b9936302431348b263e5f70 Mon Sep 17 00:00:00 2001
From: Colin Ian King <colin.king@canonical.com>
Date: Thu, 30 Sep 2021 11:19:41 +0100
Subject: drm/virtio: fix potential integer overflow on shift of a int
Git-commit: 8f4502fa284478a5264afa8a5a95511276fa9b80
Patch-mainline: v5.17-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
The left shift of unsigned int 32 bit integer constant 1 is evaluated
using 32 bit arithmetic and then assigned to a signed 64 bit integer.
In the case where i is 32 or more this can lead to an overflow. Fix
this by shifting the value 1ULL instead.
Addresses-Coverity: ("Uninitentional integer overflow")
Fixes: 8d6b006e1f51 ("drm/virtio: implement context init: handle VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210930101941.16546-1-colin.king@canonical.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/virtio/virtgpu_ioctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index 3607646d3229..5e8103a197a9 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -819,7 +819,7 @@ static int virtio_gpu_context_init_ioctl(struct drm_device *dev,
if (vfpriv->ring_idx_mask) {
valid_ring_mask = 0;
for (i = 0; i < vfpriv->num_rings; i++)
- valid_ring_mask |= 1 << i;
+ valid_ring_mask |= 1ULL << i;
if (~valid_ring_mask & vfpriv->ring_idx_mask) {
ret = -EINVAL;
--
2.38.1