diff options
| author | Benjamin Poirier <bpoirier@cumulusnetworks.com> | 2020-02-12 04:41:06 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-02-17 05:34:31 +0300 |
| commit | e404b8c7cfb31654c9024d497cec58a501501692 (patch) | |
| tree | 5a24c73695f44b92f343f993d3bee588fe8bf567 | |
| parent | e8023b030ce1748930e2dc76353a262fe47d4745 (diff) | |
| download | linux-e404b8c7cfb31654c9024d497cec58a501501692.tar.xz | |
ipv6: Fix route replacement with dev-only route
After commit 27596472473a ("ipv6: fix ECMP route replacement") it is no
longer possible to replace an ECMP-able route by a non ECMP-able route.
For example,
ip route add 2001:db8::1/128 via fe80::1 dev dummy0
ip route replace 2001:db8::1/128 dev dummy0
does not work as expected.
Tweak the replacement logic so that point 3 in the log of the above commit
becomes:
3. If the new route is not ECMP-able, and no matching non-ECMP-able route
exists, replace matching ECMP-able route (if any) or add the new route.
We can now summarize the entire replace semantics to:
When doing a replace, prefer replacing a matching route of the same
"ECMP-able-ness" as the replace argument. If there is no such candidate,
fallback to the first route found.
Fixes: 27596472473a ("ipv6: fix ECMP route replacement")
Signed-off-by: Benjamin Poirier <bpoirier@cumulusnetworks.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv6/ip6_fib.c | 7 | ||||
| -rwxr-xr-x | tools/testing/selftests/net/fib_tests.sh | 6 |
2 files changed, 10 insertions, 3 deletions
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 58fbde244381..72abf892302f 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -1102,8 +1102,7 @@ static int fib6_add_rt2node(struct fib6_node *fn, struct fib6_info *rt, found++; break; } - if (rt_can_ecmp) - fallback_ins = fallback_ins ?: ins; + fallback_ins = fallback_ins ?: ins; goto next_iter; } @@ -1146,7 +1145,9 @@ next_iter: } if (fallback_ins && !found) { - /* No ECMP-able route found, replace first non-ECMP one */ + /* No matching route with same ecmp-able-ness found, replace + * first matching route + */ ins = fallback_ins; iter = rcu_dereference_protected(*ins, lockdep_is_held(&rt->fib6_table->tb6_lock)); diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh index 6dd403103800..60273f1bc7d9 100755 --- a/tools/testing/selftests/net/fib_tests.sh +++ b/tools/testing/selftests/net/fib_tests.sh @@ -910,6 +910,12 @@ ipv6_rt_replace_mpath() check_route6 "2001:db8:104::/64 via 2001:db8:101::3 dev veth1 metric 1024" log_test $? 0 "Multipath with single path via multipath attribute" + # multipath with dev-only + add_initial_route6 "nexthop via 2001:db8:101::2 nexthop via 2001:db8:103::2" + run_cmd "$IP -6 ro replace 2001:db8:104::/64 dev veth1" + check_route6 "2001:db8:104::/64 dev veth1 metric 1024" + log_test $? 0 "Multipath with dev-only" + # route replace fails - invalid nexthop 1 add_initial_route6 "nexthop via 2001:db8:101::2 nexthop via 2001:db8:103::2" run_cmd "$IP -6 ro replace 2001:db8:104::/64 nexthop via 2001:db8:111::3 nexthop via 2001:db8:103::3" |