From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1420212-1518184469-2-4329132333363270718 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES unknown, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1518184469; b=aFzfTzPRJhgkFDR2XVcU9yDIY+AEI+iBo7C3z2/zqza8E5s RbYOYizd6QechCu4HY9zxcYg3KfWhv8TMc4e/r4/gSpxLyi2QEur3Fa9CspoCc9J kaA52GmVV77jOlTo9sIf89XITYcWOL/kyza4C4r0FUYI6lY3pOUh1PDrtdMFESXK Elf2MAgAcEiG29bumSt6e2+SO4HCI4eL5u15/U1GfYyVbiqaXYYRGkYgaBI6raO4 1lDNgYnb7BzE8SZu+hwu1QCX9q6nak8WSGH2DAjTNb2wv+oXBS5fK1wwAsx9+AUu NtsrHuKwFIOLwijtwIvYdXggONrZ/aEHLLp2+wA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1518184469; bh=o0X7OHthX46YuIhrXiBUTSp1gs U6H7de3lu3M3Su6/o=; b=ILoC9EisVk/qlkX8lYNYJQuuOpH/R+REI86lz5oOVX pKZldvFqpLBeWxeBo4OzFONN4kWCbrOKflOeNGBvDlI9AtFtyWRba77+Tsp/J65V hZf/XcKkdNknvGTry8E9ggj4tpVJkv2Pf2fo7NDaPUZOPCiF/oOEUf4NnSfcpHfQ OlTTRM8xCAdUsyggcfMUyUxqOwxe4cIVHji+u9xai4MbCtqzhVNVYDAvBoDswjDa y12kn726aICu7W8FuuxUDFQdMfeDPb1J+4GXsLACPEHQSjNT1g3bYTSAebT21EOi CGvHWI1G1ydkzIq4eVJdITLvAhMKSN9+SuNZFUjHEvaQ== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753437AbeBINyI (ORCPT ); Fri, 9 Feb 2018 08:54:08 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:51978 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932117AbeBINpr (ORCPT ); Fri, 9 Feb 2018 08:45:47 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , "David S. Miller" Subject: [PATCH 4.14 05/22] net: igmp: add a missing rcu locking section Date: Fri, 9 Feb 2018 14:39:54 +0100 Message-Id: <20180209133934.423549422@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180209133934.024795822@linuxfoundation.org> References: <20180209133934.024795822@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit e7aadb27a5415e8125834b84a74477bfbee4eff5 ] Newly added igmpv3_get_srcaddr() needs to be called under rcu lock. Timer callbacks do not ensure this locking. ============================= WARNING: suspicious RCU usage 4.15.0+ #200 Not tainted ----------------------------- ./include/linux/inetdevice.h:216 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by syzkaller616973/4074: #0: (&mm->mmap_sem){++++}, at: [<00000000bfce669e>] __do_page_fault+0x32d/0xc90 arch/x86/mm/fault.c:1355 #1: ((&im->timer)){+.-.}, at: [<00000000619d2f71>] lockdep_copy_map include/linux/lockdep.h:178 [inline] #1: ((&im->timer)){+.-.}, at: [<00000000619d2f71>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316 #2: (&(&im->lock)->rlock){+.-.}, at: [<000000005f833c5c>] spin_lock_bh include/linux/spinlock.h:315 [inline] #2: (&(&im->lock)->rlock){+.-.}, at: [<000000005f833c5c>] igmpv3_send_report+0x98/0x5b0 net/ipv4/igmp.c:600 stack backtrace: CPU: 0 PID: 4074 Comm: syzkaller616973 Not tainted 4.15.0+ #200 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4592 __in_dev_get_rcu include/linux/inetdevice.h:216 [inline] igmpv3_get_srcaddr net/ipv4/igmp.c:329 [inline] igmpv3_newpack+0xeef/0x12e0 net/ipv4/igmp.c:389 add_grhead.isra.27+0x235/0x300 net/ipv4/igmp.c:432 add_grec+0xbd3/0x1170 net/ipv4/igmp.c:565 igmpv3_send_report+0xd5/0x5b0 net/ipv4/igmp.c:605 igmp_send_report+0xc43/0x1050 net/ipv4/igmp.c:722 igmp_timer_expire+0x322/0x5c0 net/ipv4/igmp.c:831 call_timer_fn+0x228/0x820 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:541 [inline] smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:938 Fixes: a46182b00290 ("net: igmp: Use correct source address on IGMPv3 reports") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/igmp.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/ipv4/igmp.c +++ b/net/ipv4/igmp.c @@ -386,7 +386,11 @@ static struct sk_buff *igmpv3_newpack(st pip->frag_off = htons(IP_DF); pip->ttl = 1; pip->daddr = fl4.daddr; + + rcu_read_lock(); pip->saddr = igmpv3_get_srcaddr(dev, &fl4); + rcu_read_unlock(); + pip->protocol = IPPROTO_IGMP; pip->tot_len = 0; /* filled in later */ ip_select_ident(net, skb, NULL);