Commit 5bd4f20d authored by liuyuntao's avatar liuyuntao Committed by Gerd Hoffmann
Browse files

virtio-gpu: fix possible memory allocation failure 



When kmem_cache_zalloc in virtio_gpu_get_vbuf fails, it will return
an error code. But none of its callers checks this error code, and
a core dump will take place.

Considering many of its callers can't handle such error, I add
a __GFP_NOFAIL flag when calling kmem_cache_zalloc to make sure
it won't fail, and delete those unused error handlings.

Fixes: dc5698e8 ("Add virtio gpu driver.")
Signed-off-by: default avatarYuntao Liu <liuyuntao10@huawei.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210828104321.3410312-1-liuyuntao10@huawei.com


Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
parent 91241ee2

drivers/gpu/drm/virtio/virtgpu_vq.c

+1 −7
Original line number Diff line number Diff line
@@ -91,9 +91,7 @@ virtio_gpu_get_vbuf(struct virtio_gpu_device *vgdev, 
{

	struct virtio_gpu_vbuffer *vbuf;



	vbuf = kmem_cache_zalloc(vgdev->vbufs, GFP_KERNEL);

	if (!vbuf)

		return ERR_PTR(-ENOMEM);

	vbuf = kmem_cache_zalloc(vgdev->vbufs, GFP_KERNEL | __GFP_NOFAIL);



	BUG_ON(size > MAX_INLINE_CMD_SIZE ||

	       size < sizeof(struct virtio_gpu_ctrl_hdr));
@@ -147,10 +145,6 @@ static void *virtio_gpu_alloc_cmd_resp(struct virtio_gpu_device *vgdev, 


	vbuf = virtio_gpu_get_vbuf(vgdev, cmd_size,

				   resp_size, resp_buf, cb);

	if (IS_ERR(vbuf)) {

		*vbuffer_p = NULL;

		return ERR_CAST(vbuf);

	}

	*vbuffer_p = vbuf;

	return (struct virtio_gpu_command *)vbuf->buf;

}