From: Michael S. Tsirkin <mst@xxxxxxxxxx>
commit 1861ba626ae9b98136f3e504208cdef6b29cd3ec upstream.
A recently added error path does not mark ring unused when exiting on
OOM, which will lead to BUG on the next entry in debug builds.
TODO: refactor code so we have START_USE and END_USE in the same function.
Fixes: fc6d70f40b3d ("virtio_ring: check desc == NULL when using indirect with packed")
Cc: "Xuan Zhuo" <xuanzhuo@xxxxxxxxxxxxxxxxx>
Cc: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
Reviewed-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/virtio/virtio_ring.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1124,8 +1124,10 @@ static inline int virtqueue_add_packed(s
if (virtqueue_use_indirect(_vq, total_sg)) {
err = virtqueue_add_indirect_packed(vq, sgs, total_sg, out_sgs,
in_sgs, data, gfp);
- if (err != -ENOMEM)
+ if (err != -ENOMEM) {
+ END_USE(vq);
return err;
+ }
/* fall back on direct */
}
