Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Andy Lutomirski <luto@kernel.org>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Tiwei Bie <tiwei.bie@intel.com>
Subject: [PATCH 4.9 22/86] virtio_ring: fix num_free handling in error case
Date:   Fri, 16 Mar 2018 16:22:45 +0100
Message-Id: <20180316152318.866123947@linuxfoundation.org>
In-Reply-To: <20180316152317.167709497@linuxfoundation.org>
References: <20180316152317.167709497@linuxfoundation.org>
User-Agent: quilt/0.65
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Tiwei Bie <tiwei.bie@intel.com>

commit e82df670235138575b37ff0ec24412a471efd97f upstream.

The vq->vq.num_free hasn't been changed when error happens,
so it shouldn't be changed when handling the error.

Fixes: 780bc7903a32 ("virtio_ring: Support DMA APIs")
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Tiwei Bie <tiwei.bie@intel.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 deletions(-)

--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -423,8 +423,6 @@ unmap_release:
 		i = vq->vring.desc[i].next;
 	}
 
-	vq->vq.num_free += total_sg;
-
 	if (indirect)
 		kfree(desc);