[PATCH 4.4 012/113] virtio: fix memory leak in virtqueue_add()

Greg Kroah-Hartman
2016-09-05T16:48:40Z

From: Wei Yongjun <weiyj.lk@gmail.com>

commit 58625edf9e2515ed41dac2a24fa8004030a87b87 upstream.

When using the indirect buffers feature, 'desc' is allocated in
virtqueue_add() but isn't freed before leaving on a ring full error,
causing a memory leak.

For example, it seems rather clear that this can trigger
with virtio net if mergeable buffers are not used.

Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/virtio/virtio_ring.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -202,6 +202,8 @@ static inline int virtqueue_add(struct v
* host should service the ring ASAP. */
if (out_sgs)
vq->notify(&vq->vq);
+ if (indirect)
+ kfree(desc);
END_USE(vq);
return -ENOSPC;
}