From: David Ahern <dsah...@kernel.org>
Date: Wed, 1 May 2019 18:08:34 -0700
> From: David Ahern <dsah...@gmail.com>
>
> Ian and Alan both reported seeing overflows after upgrades to 5.x kernels:
> neighbour: arp_cache: neighbor table overflow!
>
> Alan's mpls script helped get to the bottom of this bug. When a new entry
> is created the gc_entries counter is bumped in neigh_alloc to check if a
> new one is allowed to be created. ___neigh_create then searches for an
> existing entry before inserting the just allocated one. If an entry
> already exists, the new one is dropped in favor of the existing one. In
> this case the cleanup path needs to drop the gc_entries counter. There
> is no memory leak, only a counter leak.
>
> Fixes: 58956317c8d ("neighbor: Improve garbage collection")
> Reported-by: Ian Kumlien <ian.kuml...@gmail.com>
> Reported-by: Alan Maguire <alan.magu...@oracle.com>
> Signed-off-by: David Ahern <dsah...@gmail.com>
Applied and queued up for -stable.
