[PATCH net-next] net/core: ensure features get disabled on new lower devs
From: Jarod Wilson <hidden>
Date: 2015-11-03 20:37:18
Also in:
lkml
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
With moving netdev_sync_lower_features() after the .ndo_set_features
calls, I neglected to verify that devices added *after* a flag had been
disabled on an upper device were properly added with that flag disabled as
well. This currently happens, because we exit __netdev_update_features()
when we see dev->features == features for the upper dev. We can retain the
optimization of leaving without calling .ndo_set_features with a bit of
tweaking and a goto here.
Changing err to ret was somewhat arbitrary and makes the patch look more
involved, but seems to better fit the altered use.
Fixes: fd867d51f ("net/core: generic support for disabling netdev features down stack")
CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jay Vosburgh <redacted>
CC: Veaceslav Falico <redacted>
CC: Andy Gospodarek <redacted>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Nikolay Aleksandrov <razor@blackwall.org>
CC: Michal Kubecek <redacted>
CC: Alexander Duyck <redacted>
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <redacted>
---
net/core/dev.c | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index 8ce3f74..90e0a62 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c@@ -6402,7 +6402,7 @@ int __netdev_update_features(struct net_device *dev) struct net_device *upper, *lower; netdev_features_t features; struct list_head *iter; - int err = 0; + int ret = 0; ASSERT_RTNL();
@@ -6419,31 +6419,34 @@ int __netdev_update_features(struct net_device *dev) features = netdev_sync_upper_features(dev, upper, features); if (dev->features == features) - return 0; + goto sync_lower; netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", &dev->features, &features); if (dev->netdev_ops->ndo_set_features) - err = dev->netdev_ops->ndo_set_features(dev, features); + ret = dev->netdev_ops->ndo_set_features(dev, features); - if (unlikely(err < 0)) { + if (unlikely(ret < 0)) { netdev_err(dev, "set_features() failed (%d); wanted %pNF, left %pNF\n", - err, &features, &dev->features); + ret, &features, &dev->features); return -1; } + if (!ret) { + dev->features = features; + ret = 1; + } + +sync_lower: /* some features must be disabled on lower devices when disabled * on an upper device (think: bonding master or bridge) */ netdev_for_each_lower_dev(dev, lower, iter) netdev_sync_lower_features(dev, lower, features); - if (!err) - dev->features = features; - - return 1; + return ret; } /**
--
1.8.3.1