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

ipv6: change route cache aging logic

to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: ipv6-change-route-cache-aging-logic.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 Feb 7 11:29:33 PST 2018

From: Wei Wang weiwan@google.com Date: Fri, 26 Jan 2018 11:40:17 -0800 Subject: ipv6: change route cache aging logic

From: Wei Wang weiwan@google.com

[ Upstream commit 31afeb425f7fad8bcf9561aeb0b8405479f97a98 ]

In current route cache aging logic, if a route has both RTF_EXPIRE and RTF_GATEWAY set, the route will only be removed if the neighbor cache has no NTF_ROUTER flag. Otherwise, even if the route has expired, it won't get deleted. Fix this logic to always check if the route has expired first and then do the gateway neighbor cache check if previous check decide to not remove the exception entry.

Fixes: 1859bac04fb6 ("ipv6: remove from fib tree aged out RTF_CACHE dst") Signed-off-by: Wei Wang weiwan@google.com Signed-off-by: Eric Dumazet edumazet@google.com Acked-by: Martin KaFai Lau kafai@fb.com Acked-by: Paolo Abeni pabeni@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv6/route.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-)

--- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1586,12 +1586,19 @@ static void rt6_age_examine_exception(st * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when * expired, independently from their aging, as per RFC 8201 section 4 */ - if (!(rt->rt6i_flags & RTF_EXPIRES) && - time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) { - RT6_TRACE("aging clone %p\n", rt); + if (!(rt->rt6i_flags & RTF_EXPIRES)) { + if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) { + RT6_TRACE("aging clone %p\n", rt); + rt6_remove_exception(bucket, rt6_ex); + return; + } + } else if (time_after(jiffies, rt->dst.expires)) { + RT6_TRACE("purging expired route %p\n", rt); rt6_remove_exception(bucket, rt6_ex); return; - } else if (rt->rt6i_flags & RTF_GATEWAY) { + } + + if (rt->rt6i_flags & RTF_GATEWAY) { struct neighbour *neigh; __u8 neigh_flags = 0;

@@ -1606,11 +1613,8 @@ static void rt6_age_examine_exception(st rt6_remove_exception(bucket, rt6_ex); return; } - } else if (__rt6_check_expired(rt)) { - RT6_TRACE("purging expired route %p\n", rt); - rt6_remove_exception(bucket, rt6_ex); - return; } + gc_args->more++; }

Patches currently in stable-queue which might be from weiwan@google.com are

queue-4.15/ipv6-change-route-cache-aging-logic.patch