This patch fixes following problems :
1) percpu_counter_init() can return an error, therefore
init_frag_mem_limit() must propagate this error so that
inet_frags_init_net() can do the same up to its callers.
2) If ip[46]_frags_ns_ctl_register() fail, we must unwind
properly and free the percpu_counter.
Without this fix, we leave freed object in percpu_counters
global list (if CONFIG_HOTPLUG_CPU) leading to crashes.
This bug was detected by KASAN and syzkaller tool
(http://github.com/google/syzkaller)
Fixes: 6d7b857d54 ("net: use lib/percpu_counter API for fragmentation mem accounting")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
1d6119baf0