virtio_net: check virtqueue_add_sgs() return value

As virtqueue_add_sgs() can fail, we should check the return value.

Addresses-Coverity-ID: 1464439 ("Unchecked return value")
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index b0b81458ca94eb5b0a312dbb3f55cf7e10bc1f56..13952e2dba5e97961ce7f7537d7369c5fc4192b7 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1743,6 +1743,7 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
 {
        struct scatterlist *sgs[4], hdr, stat;
        unsigned out_num = 0, tmp;
+       int ret;
 
        /* Caller should know better */
        BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
@@ -1762,7 +1763,12 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
        sgs[out_num] = &stat;
 
        BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
-       virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
+       ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
+       if (ret < 0) {
+               dev_warn(&vi->vdev->dev,
+                        "Failed to add sgs for command vq: %d\n.", ret);
+               return false;
+       }
 
        if (unlikely(!virtqueue_kick(vi->cvq)))
                return vi->ctrl->status == VIRTIO_NET_OK;