Commit ae7352d3 authored May 27, 2019 by Eric Dumazet Committed by David S. Miller May 28, 2019

inet: frags: call inet_frags_fini() after unregister_pernet_subsys()



Both IPv6 and 6lowpan are calling inet_frags_fini() too soon.

inet_frags_fini() is dismantling a kmem_cache, that might be needed
later when unregister_pernet_subsys() eventually has to remove
frags queues from hash tables and free them.

This fixes potential use-after-free, and is a prereq for the following patch.

Fixes: d4ad4d22 ("inet: frags: use kmem_cache for inet_frag_queue")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 6b73d197

net/ieee802154/6lowpan/reassembly.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -540,7 +540,7 @@ err_sysctl:

		void lowpan_net_frag_exit(void)
		{
		inet_frags_fini(&lowpan_frags);
		lowpan_frags_sysctl_unregister();
		unregister_pernet_subsys(&lowpan_frags_ops);
		inet_frags_fini(&lowpan_frags);
		}

net/ipv6/reassembly.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -583,8 +583,8 @@ err_protocol:

		void ipv6_frag_exit(void)
		{
		inet_frags_fini(&ip6_frags);
		ip6_frags_sysctl_unregister();
		unregister_pernet_subsys(&ip6_frags_ops);
		inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT);
		inet_frags_fini(&ip6_frags);
		}

Admin message