From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756513AbcIUTuI (ORCPT ); Wed, 21 Sep 2016 15:50:08 -0400 Received: from mailrelay105.isp.belgacom.be ([195.238.20.132]:25506 "EHLO mailrelay105.isp.belgacom.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752502AbcIUTuF (ORCPT ); Wed, 21 Sep 2016 15:50:05 -0400 X-Belgacom-Dynamic: yes X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: =?us-ascii?q?A2A4AwDK4+JX/yJEiNleHAEBBAEBCgEBg?= =?us-ascii?q?wI5AQEBAQEegVONM6k1gg+CBIYegWc5FAECAQEBAQEBAV4nhT4jKXEkE4hPtUa?= =?us-ascii?q?GfzGGN452BZl1j2ICj2qQYx42gkkBTAMcgVI8NIQXKoIEAQEB?= From: Fabian Frederick To: Florian Westphal Cc: Eric Dumazet , Pablo Neira Ayuso , linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org, fabf@skynet.be Subject: [PATCH 1/1 linux-next] netfilter: conntrack: fix kmemleak false positive Date: Wed, 21 Sep 2016 21:49:57 +0200 Message-Id: <1474487397-11032-1-git-send-email-fabf@skynet.be> X-Mailer: git-send-email 2.8.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since commit f330a7fdbe16 ("netfilter: conntrack: get rid of conntrack timer") closed connections remain longer in /proc/net/nf_conntrack Running current kernel; just after boot: cat /proc/net/nf_conntrack | wc -l = 5 4 minutes required to clean up the table. Going back to kernel version before commit above there are no connections after some seconds. Referring to the commit changelog this was an expected behaviour but it results in temporary kmemleak reports: unreferenced object 0xffff88003b0e6600 (size 248): comm "rsyslogd", pid 1595, jiffies 4294741312 (age 7.343s) ... backtrace: [] kmemleak_alloc+0x23/0x40 [] kmem_cache_alloc+0xd9/0x180 [] __nf_conntrack_alloc.isra.50+0x48/0x170 [] nf_conntrack_in+0x3a2/0x5f0 [] ipv4_conntrack_local+0x40/0x50 [] nf_iterate+0x5d/0x70 [] nf_hook_slow+0x5f/0xb0 [] __ip_local_out+0xad/0xe0 [] ip_local_out+0x17/0x40 [] ip_send_skb+0x14/0x40 [] udp_send_skb+0x91/0x260 [] udp_sendmsg+0x2f5/0x950 [] inet_sendmsg+0x60/0x90 [] sock_sendmsg+0x33/0x40 [] SYSC_sendto+0xee/0x160 [] SyS_sendto+0x9/0x10 (248 bytes being an nf_conn structure) Those structures being cleared in gc_worker() later on we can't talk about unreferenced object so this patch uses kmemleak_not_leak() to prevent those warnings. Signed-off-by: Fabian Frederick --- net/netfilter/nf_conntrack_core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 50106a1..59396f3 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1022,6 +1022,7 @@ __nf_conntrack_alloc(struct net *net, * SLAB_DESTROY_BY_RCU. */ ct = kmem_cache_alloc(nf_conntrack_cachep, gfp); + kmemleak_not_leak(ct); if (ct == NULL) goto out; -- 2.8.1