fib_rules: Added NLM_F_EXCL support to fib_nl_newrule
authorMateusz Bajorski <mateusz.bajorski@nokia.com>
Wed, 29 Jun 2016 07:22:10 +0000 (09:22 +0200)
committerDavid S. Miller <davem@davemloft.net>
Thu, 30 Jun 2016 12:23:19 +0000 (08:23 -0400)
commit153380ec4b9b6802bba61ebd34da432a54994e9d
tree0391517ef88107a49eae9825f4a7cd077c8537c4
parent2631b79f6cb8b634fe41b77de9c4add0ec6b3cae
fib_rules: Added NLM_F_EXCL support to fib_nl_newrule

When adding rule with NLM_F_EXCL flag then check if the same rule exist.
If yes then exit with -EEXIST.

This is already implemented in iproute2:
        if (cmd == RTM_NEWRULE) {
                req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL;
                req.r.rtm_type = RTN_UNICAST;
        }

Tested ipv4 and ipv6 with net-next linux on qemu x86

expected behavior after patch:
localhost ~ # ip rule
0:    from all lookup local
32766:    from all lookup main
32767:    from all lookup default
localhost ~ # ip rule add from 10.46.177.97 lookup 104 pref 1005
localhost ~ # ip rule add from 10.46.177.97 lookup 104 pref 1005
RTNETLINK answers: File exists
localhost ~ # ip rule
0:    from all lookup local
1005:    from 10.46.177.97 lookup 104
32766:    from all lookup main
32767:    from all lookup default

There was already topic regarding this but I don't see any changes
merged and problem still occurs.
https://lkml.kernel.org/r/1135778809.5944.7.camel+%28%29+localhost+%21+localdomain

Signed-off-by: Mateusz Bajorski <mateusz.bajorski@nokia.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/core/fib_rules.c