netdev - [PATCH net-next 04/10] netvsc: check error return when restoring channels and mtu

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed,  9 Aug 2017 17:46:06 -0700
From:   Stephen Hemminger <stephen@...workplumber.org>
To:     kys@...rosoft.com, haiyangz@...rosoft.com, sthemmin@...rosoft.com
Cc:     devel@...uxdriverproject.org, netdev@...r.kernel.org
Subject: [PATCH net-next 04/10] netvsc: check error return when restoring channels and mtu

If setting new values fails, and the attempt to restore original
settings fails. Then log an error and leave device down.
This should never happen, but if it does don't go down in flames.

Signed-off-by: Stephen Hemminger <sthemmin@...rosoft.com>
---
 drivers/net/hyperv/netvsc_drv.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 07015b1c42c6..c7391889938b 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -845,7 +845,13 @@ static int netvsc_set_channels(struct net_device *net,
 	} else {
 		ret = PTR_ERR(nvdev);
 		device_info.num_chn = orig;
-		rndis_filter_device_add(dev, &device_info);
+		nvdev = rndis_filter_device_add(dev, &device_info);
+
+		if (IS_ERR(nvdev)) {
+			netdev_err(net, "restoring channel setting failed: %ld\n",
+				   PTR_ERR(nvdev));
+			return ret;
+		}
 	}
 
 	if (was_opened)
@@ -953,10 +959,16 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 
 		/* Attempt rollback to original MTU */
 		ndev->mtu = orig_mtu;
-		rndis_filter_device_add(hdev, &device_info);
+		nvdev = rndis_filter_device_add(hdev, &device_info);
 
 		if (vf_netdev)
 			dev_set_mtu(vf_netdev, orig_mtu);
+
+		if (IS_ERR(nvdev)) {
+			netdev_err(ndev, "restoring mtu failed: %ld\n",
+				   PTR_ERR(nvdev));
+			return ret;
+		}
 	}
 
 	if (was_opened)
-- 
2.11.0