releases/4.15.10/virtio_ring-fix-num_free-handling-in-error-case.patch

   1 From e82df670235138575b37ff0ec24412a471efd97f Mon Sep 17 00:00:00 2001
   2 From: Tiwei Bie <tiwei.bie@intel.com>
   3 Date: Fri, 23 Feb 2018 19:41:30 +0800
   4 Subject: virtio_ring: fix num_free handling in error case
   5
   6 From: Tiwei Bie <tiwei.bie@intel.com>
   7
   8 commit e82df670235138575b37ff0ec24412a471efd97f upstream.
   9
  10 The vq->vq.num_free hasn't been changed when error happens,
  11 so it shouldn't be changed when handling the error.
  12
  13 Fixes: 780bc7903a32 ("virtio_ring: Support DMA APIs")
  14 Cc: Andy Lutomirski <luto@kernel.org>
  15 Cc: Michael S. Tsirkin <mst@redhat.com>
  16 Cc: stable@vger.kernel.org
  17 Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
  18 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20
  21 ---
  22  drivers/virtio/virtio_ring.c |    2 --
  23  1 file changed, 2 deletions(-)
  24
  25 --- a/drivers/virtio/virtio_ring.c
  26 +++ b/drivers/virtio/virtio_ring.c
  27 @@ -428,8 +428,6 @@ unmap_release:
  28                 i = virtio16_to_cpu(_vq->vdev, vq->vring.desc[i].next);
  29         }
  30
  31 -       vq->vq.num_free += total_sg;
  32 -
  33         if (indirect)
  34                 kfree(desc);
  35