From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit 09c4b49457434fa74749ad6194ef28464d9f5df9 ]
This doesn't affect runtime because in the current code "idx" is always valid.
First, we read from "vgdev->capsets[idx].max_size" before checking whether "idx" is within bounds. And secondly the bounds check is off by one so we could end up reading one element beyond the end of the vgdev->capsets[] array.
Fixes: 62fb7a5e1096 ("virtio-gpu: add 3d/virgl support") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Link: http://patchwork.freedesktop.org/patch/msgid/20180704094250.m7sgvvzg3dhcvv3h... Signed-off-by: Gerd Hoffmann kraxel@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/virtio/virtgpu_vq.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index a1b3ea1ccb65b..772a5a3b0ce1a 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -681,11 +681,11 @@ int virtio_gpu_cmd_get_capset(struct virtio_gpu_device *vgdev, { struct virtio_gpu_get_capset *cmd_p; struct virtio_gpu_vbuffer *vbuf; - int max_size = vgdev->capsets[idx].max_size; + int max_size; struct virtio_gpu_drv_cap_cache *cache_ent; void *resp_buf;
- if (idx > vgdev->num_capsets) + if (idx >= vgdev->num_capsets) return -EINVAL;
if (version > vgdev->capsets[idx].max_version) @@ -695,6 +695,7 @@ int virtio_gpu_cmd_get_capset(struct virtio_gpu_device *vgdev, if (!cache_ent) return -ENOMEM;
+ max_size = vgdev->capsets[idx].max_size; cache_ent->caps_cache = kmalloc(max_size, GFP_KERNEL); if (!cache_ent->caps_cache) { kfree(cache_ent);