Patch "macvlan: filter out unsupported feature flags" has been added to the 4.15-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    macvlan: filter out unsupported feature flags

to the 4.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     macvlan-filter-out-unsupported-feature-flags.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Wed Mar 28 18:37:51 CEST 2018
From: Shannon Nelson <shannon.nelson@oracle.com>
Date: Thu, 8 Mar 2018 16:17:23 -0800
Subject: macvlan: filter out unsupported feature flags

From: Shannon Nelson <shannon.nelson@oracle.com>


[ Upstream commit 13fbcc8dc573482dd3f27568257fd7087f8935f4 ]

Adding a macvlan device on top of a lowerdev that supports
the xfrm offloads fails with a new regression:
  # ip link add link ens1f0 mv0 type macvlan
  RTNETLINK answers: Operation not permitted

Tracing down the failure shows that the macvlan device inherits
the NETIF_F_HW_ESP and NETIF_F_HW_ESP_TX_CSUM feature flags
from the lowerdev, but with no dev->xfrmdev_ops API filled
in, it doesn't actually support xfrm.  When the request is
made to add the new macvlan device, the XFRM listener for
NETDEV_REGISTER calls xfrm_api_check() which fails the new
registration because dev->xfrmdev_ops is NULL.

The macvlan creation succeeds when we filter out the ESP
feature flags in macvlan_fix_features(), so let's filter them
out like we're already filtering out ~NETIF_F_NETNS_LOCAL.
When XFRM support is added in the future, we can add the flags
into MACVLAN_FEATURES.

This same problem could crop up in the future with any other
new feature flags, so let's filter out any flags that aren't
defined as supported in macvlan.

Fixes: d77e38e612a0 ("xfrm: Add an IPsec hardware offloading API")
Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/macvlan.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1036,7 +1036,7 @@ static netdev_features_t macvlan_fix_fea
 	lowerdev_features &= (features | ~NETIF_F_LRO);
 	features = netdev_increment_features(lowerdev_features, features, mask);
 	features |= ALWAYS_ON_FEATURES;
-	features &= ~NETIF_F_NETNS_LOCAL;
+	features &= (ALWAYS_ON_FEATURES | MACVLAN_FEATURES);
 
 	return features;
 }


Patches currently in stable-queue which might be from shannon.nelson@oracle.com are

queue-4.15/macvlan-filter-out-unsupported-feature-flags.patch