Re: [PATCH net 0/2] ip: fix creation flags reported in RTM_NEWROUTE events

On Fri, Sep 09, 2016 at 04:51:26PM -0700, David Miller wrote:

From: Guillaume Nault <redacted>
Date: Wed, 7 Sep 2016 17:18:50 +0200

quoted

Netlink messages sent to user-space upon RTM_NEWROUTE events have their
nlmsg_flags field inconsistently set. While the NLM_F_REPLACE and
NLM_F_APPEND bits are correctly handled, NLM_F_CREATE and NLM_F_EXCL
are always 0.

This series sets the NLM_F_CREATE and NLM_F_EXCL bits when applicable,
for IPv4 and IPv6.

Since IPv6 ignores the NLM_F_APPEND flags in requests, this flag isn't
reported in RTM_NEWROUTE IPv6 events. This keeps IPv6 internal
consistency (same flag semantic for user requests and kernel events) at
the cost of bringing different flag interpretation for IPv4 and IPv6.

I'm applying this series to net-next so that it has time to cook and
expose anything in userland that might break due to these changes.

I briefly considered applying this to net but I think that is
premature at least for the time being.

Makes sense, and this could be considered a feature enhancement after
all.
Thanks David.