From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58262 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751185AbdIOGVh (ORCPT ); Fri, 15 Sep 2017 02:21:37 -0400 Subject: Patch "ipv6: do not set sk_destruct in IPV6_ADDRFORM sockopt" has been added to the 4.12-stable tree To: lucien.xin@gmail.com, chunwang@redhat.com, davem@davemloft.net, gregkh@linuxfoundation.org, pabeni@redhat.com Cc: , From: Date: Thu, 14 Sep 2017 23:21:31 -0700 Message-ID: <1505456491303@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled ipv6: do not set sk_destruct in IPV6_ADDRFORM sockopt to the 4.12-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ipv6-do-not-set-sk_destruct-in-ipv6_addrform-sockopt.patch and it can be found in the queue-4.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Thu Sep 14 23:20:23 PDT 2017 From: Xin Long Date: Mon, 28 Aug 2017 10:45:01 +0800 Subject: ipv6: do not set sk_destruct in IPV6_ADDRFORM sockopt From: Xin Long [ Upstream commit e8d411d2980723b8f8ba8e4dd78b694c5fd9ea3e ] ChunYu found a kernel warn_on during syzkaller fuzzing: [40226.038539] WARNING: CPU: 5 PID: 23720 at net/ipv4/af_inet.c:152 inet_sock_destruct+0x78d/0x9a0 [40226.144849] Call Trace: [40226.147590] [40226.149859] dump_stack+0xe2/0x186 [40226.176546] __warn+0x1a4/0x1e0 [40226.180066] warn_slowpath_null+0x31/0x40 [40226.184555] inet_sock_destruct+0x78d/0x9a0 [40226.246355] __sk_destruct+0xfa/0x8c0 [40226.290612] rcu_process_callbacks+0xaa0/0x18a0 [40226.336816] __do_softirq+0x241/0x75e [40226.367758] irq_exit+0x1f6/0x220 [40226.371458] smp_apic_timer_interrupt+0x7b/0xa0 [40226.376507] apic_timer_interrupt+0x93/0xa0 The warn_on happned when sk->sk_rmem_alloc wasn't 0 in inet_sock_destruct. As after commit f970bd9e3a06 ("udp: implement memory accounting helpers"), udp has changed to use udp_destruct_sock as sk_destruct where it would udp_rmem_release all rmem. But IPV6_ADDRFORM sockopt sets sk_destruct with inet_sock_destruct after changing family to PF_INET. If rmem is not 0 at that time, and there is no place to release rmem before calling inet_sock_destruct, the warn_on will be triggered. This patch is to fix it by not setting sk_destruct in IPV6_ADDRFORM sockopt any more. As IPV6_ADDRFORM sockopt only works for tcp and udp. TCP sock has already set it's sk_destruct with inet_sock_destruct and UDP has set with udp_destruct_sock since they're created. Fixes: f970bd9e3a06 ("udp: implement memory accounting helpers") Reported-by: ChunYu Wang Signed-off-by: Xin Long Acked-by: Paolo Abeni Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ipv6_sockglue.c | 1 - 1 file changed, 1 deletion(-) --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -242,7 +242,6 @@ static int do_ipv6_setsockopt(struct soc pktopt = xchg(&np->pktoptions, NULL); kfree_skb(pktopt); - sk->sk_destruct = inet_sock_destruct; /* * ... and add it to the refcnt debug socks count * in the new family. -acme Patches currently in stable-queue which might be from lucien.xin@gmail.com are queue-4.12/ip6_gre-update-mtu-properly-in-ip6gre_err.patch queue-4.12/ipv6-set-dst.obsolete-when-a-cached-route-has-expired.patch queue-4.12/ipv6-do-not-set-sk_destruct-in-ipv6_addrform-sockopt.patch queue-4.12/sctp-avoid-out-of-bounds-reads-from-address-storage.patch