[dpdk-stable] [dpdk-dev] [PATCH v3] net/virtio-user: fix return value of tap offload sets not checked

[Yunjian Wang <wangyunjian@huawei.com>]

The function vhost_kernel_tap_set_offload() could return errors,
the return value need to be checked. And there is no need to fail
when error is -ENOTSUP.

Fixes: 1db4d2330bc8 ("net/virtio-user: check negotiated features before set")
Cc: stable@dpdk.org

Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
---
v3:
  * Fix return value check incorrectly in v2
v2:
  * No need to fail when error is -ENOTSUP.
---
 drivers/net/virtio/virtio_user/vhost_kernel_tap.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio/virtio_user/vhost_kernel_tap.c b/drivers/net/virtio/virtio_user/vhost_kernel_tap.c
index 76bf75423..52f3ee529 100644
--- a/drivers/net/virtio/virtio_user/vhost_kernel_tap.c
+++ b/drivers/net/virtio/virtio_user/vhost_kernel_tap.c
@@ -66,6 +66,7 @@ vhost_kernel_open_tap(char **p_ifname, int hdr_size, int req_mq,
 	int sndbuf = INT_MAX;
 	struct ifreq ifr;
 	int tapfd;
+	int ret;
 
 	/* TODO:
 	 * 1. verify we can get/set vnet_hdr_len, tap_probe_vnet_hdr_len
@@ -131,7 +132,9 @@ vhost_kernel_open_tap(char **p_ifname, int hdr_size, int req_mq,
 		goto error;
 	}
 
-	vhost_kernel_tap_set_offload(tapfd, features);
+	ret = vhost_kernel_tap_set_offload(tapfd, features);
+	if (ret < 0 && ret != -ENOTSUP)
+		goto error;
 
 	memset(&ifr, 0, sizeof(ifr));
 	ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER;
-- 
2.19.1