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

diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 020070d483d3..4735bd1c7321 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -648,11 +648,11 @@ 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) @@ -662,6 +662,7 @@ 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);