[PATCH 5.19 0348/1157] virtio-gpu: fix a missing check to avoid NULL dereference
From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 19:28:32 EST
From: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx>
[ Upstream commit bd63f11f4c3c46afec07d821f74736161ff6e526 ]
'cache_ent' could be set NULL inside virtio_gpu_cmd_get_capset()
and it will lead to a NULL dereference by a lately use of it
(i.e., ptr = cache_ent->caps_cache). Fix it with a NULL check.
Fixes: 62fb7a5e10962 ("virtio-gpu: add 3d/virgl support")
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx>
Reviewed-by: Chia-I Wu <olvaffe@xxxxxxxxx>
Link: http://patchwork.freedesktop.org/patch/msgid/20220327050945.1614-1-xiam0nd.tong@xxxxxxxxx
[ kraxel: minor codestyle fixup ]
Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/virtio/virtgpu_ioctl.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index f8d83358d2a0..9b2702116f93 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -580,8 +580,10 @@ static int virtio_gpu_get_caps_ioctl(struct drm_device *dev,
spin_unlock(&vgdev->display_info_lock);
/* not in cache - need to talk to hw */
- virtio_gpu_cmd_get_capset(vgdev, found_valid, args->cap_set_ver,
- &cache_ent);
+ ret = virtio_gpu_cmd_get_capset(vgdev, found_valid, args->cap_set_ver,
+ &cache_ent);
+ if (ret)
+ return ret;
virtio_gpu_notify(vgdev);
copy_exit:
--
2.35.1