Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755704Ab2JPSD3 (ORCPT ); Tue, 16 Oct 2012 14:03:29 -0400 Received: from mail-ob0-f174.google.com ([209.85.214.174]:45575 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755626Ab2JPSD1 (ORCPT ); Tue, 16 Oct 2012 14:03:27 -0400 MIME-Version: 1.0 In-Reply-To: <20121016162709.GA13897@1984> References: <20121011212733.GB26025@liondog.tnic> <20121011233206.GA10370@1984> <20121016162709.GA13897@1984> Date: Tue, 16 Oct 2012 11:03:26 -0700 Message-ID: Subject: Re: amd64, v3.6.0: Kernel panic + BUG at net/netfilter/nf_conntrack_core.c:220! From: Ian Applegate To: Pablo Neira Ayuso Cc: Borislav Petkov , linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org, netfilter@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7028 Lines: 146 I will be doing much wider testing on 3.6 this week, will keep you updated if I see this issue again. I don't see a logical way into that trap myself and looking at the revision history we've been running this code path for a very long time without issue. The machine in question has a fairly high MTBF which is why I thought this odd, but it is most likely random memory corruption. Thanks! Ian Applegate On Tue, Oct 16, 2012 at 9:27 AM, Pablo Neira Ayuso wrote: > On Fri, Oct 12, 2012 at 01:32:06AM +0200, Pablo Neira Ayuso wrote: >> On Thu, Oct 11, 2012 at 11:27:33PM +0200, Borislav Petkov wrote: >> > On Thu, Oct 11, 2012 at 12:13:33PM -0700, Ian Applegate wrote: >> > > On machines serving mainly http traffic we are seeing the following >> > > panic, which is not yet reproducible. >> > >> > Must be this BUG_ON: >> > >> > if (!nf_ct_is_confirmed(ct)) { >> > BUG_ON(hlist_nulls_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode)); >> > hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); >> > } >> >> At quick glance, I think we're hitting a memory corruption, I don't >> see by now any sane code path to reach that bugtrap. > > Did you manage to obtain more information regarding this bug? > > I don't find any recent change in the conntrack source that may lead > us to hit that. > > Thanks. > >> More comments below: >> >> > Spamming some more lists and leaving the rest for reference. >> > >> > > >> > > >> > > [180926.566743] ------------[ cut here ]------------ >> > > [180926.572034] kernel BUG at net/netfilter/nf_conntrack_core.c:220! >> > > [180926.578873] invalid opcode: 0000 [#1] SMP >> > > [180926.583594] Modules linked in: xfs exportfs ipmi_devintf ipmi_si >> > > ipmi_msghandler dm_mod md_mod nf_conntr >> > > ack_ipv6 nf_defrag_ipv6 ip6table_filter ip6table_raw ip6_tables >> > > nf_conntrack_ipv4 nf_defrag_ipv4 xt_tcpudp x >> > > t_conntrack xt_multiport iptable_filter xt_NOTRACK nf_conntrack >> > > iptable_raw ip_tables x_tables nfsv4 auth_rp >> > > cgss fuse nfsv3 nfs_acl nfs fscache lockd sunrpc sfc mtd i2c_algo_bit >> > > i2c_core mdio igb dca uhci_hcd coretem >> > > p acpi_cpufreq kvm_intel kvm crc32c_intel aesni_intel ablk_helper >> > > cryptd aes_x86_64 aes_generic evdev sd_mod >> > > crc_t10dif mperf snd_pcm ahci snd_timer tpm_tis microcode snd tpm >> > > libahci tpm_bios soundcore libata snd_pag >> > > e_alloc pcspkr ehci_hcd lpc_ich usbcore mfd_core hpsa scsi_mod >> > > usb_common button processor thermal_sys >> > > [180926.657762] CPU 12 >> > > [180926.660008] Pid: 5948, comm: nginx-fl Not tainted 3.6.0-cloudflare >> > > #1 HP ProLiant DL180 G6 >> > > [180926.669820] RIP: 0010:[] [] >> > > destroy_conntrack+0x55/0xa9 [nf_conntrack] >> > > [180926.680871] RSP: 0018:ffff8805bd73fbb8 EFLAGS: 00010246 >> > > [180926.686930] RAX: 0000000000000000 RBX: ffff8806b6f56c30 RCX: >> > > ffff8805bd73fc48 >> > > [180926.695055] RDX: 0000000000000000 RSI: 0000000000000006 RDI: >> > > ffff8806b6f56c30 >> > > [180926.703179] RBP: ffffffff81651780 R08: 00000000000172e0 R09: >> > > ffffffff812cef91 >> > > [180926.711304] R10: dead000000200200 R11: dead000000100100 R12: >> > > ffff8806b6f56c30 >> > > [180926.727451] R13: 0000000000000000 R14: ffffffffa02d6030 R15: >> > > 0000000000000000 >> > > [180926.735575] FS: 00007f382cdb2710(0000) GS:ffff880627cc0000(0000) >> > > knlGS:0000000000000000 >> > > [180926.744766] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> > > [180926.751312] CR2: ffffffffff600400 CR3: 00000005bd8d3000 CR4: >> > > 00000000000007e0 >> > > [180926.759436] DR0: 0000000000000000 DR1: 0000000000000000 DR2: >> > > 0000000000000000 >> > > [180926.767560] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: >> > > 0000000000000400 >> > > [180926.775686] Process nginx-fl (pid: 5948, threadinfo >> > > ffff8805bd73e000, task ffff8805c9755960) >> > > [180926.785265] Stack: >> > > [180926.787634] 0000000000000000 ffffffff81651780 ffff8802720c2900 >> > > ffffffffa02cde78 >> > > [180926.796087] ffffffff81651ec0 ffffffffa02d6030 00000000bff0efab >> > > ffff8805ffffffff >> > > [180926.804532] 0002880500000002 0000000300000014 0000001400000003 >> > > 06ff880600000002 >> > > [180926.812985] Call Trace: >> > > [180926.815845] [] ? nf_conntrack_in+0x4ed/0x5bc >> > > [nf_conntrack] >> >> Here below the trace shows the output path to close a tcp socket. But >> the line above refers to a conntrack function that is called in the >> input path. >> >> If this process is just acting as plain http server, this backtrace >> doesn't seem consistent to me. >> >> > > [180926.824069] [] ? nf_iterate+0x41/0x77 >> > > [180926.830131] [] ? ip_options_echo+0x2ed/0x2ed >> > > [180926.836873] [] ? nf_hook_slow+0x68/0xfd >> > > [180926.843127] [] ? ip_options_echo+0x2ed/0x2ed >> > > [180926.849866] [] ? __ip_local_out+0x98/0x9d >> > > [180926.856315] [] ? ip_local_out+0x9/0x19 >> > > [180926.862465] [] ? tcp_transmit_skb+0x7ae/0x7f1 >> > > [180926.869305] [] ? virt_to_head_page+0x9/0x2c >> > > [180926.875949] [] ? tcp_send_active_reset+0xd5/0x101 >> > > [180926.883175] [] ? tcp_close+0x118/0x354 >> > > [180926.889334] [] ? inet_release+0x75/0x7b >> > > [180926.895591] [] ? sock_release+0x19/0x73 >> > > [180926.901845] [] ? sock_close+0x22/0x27 >> > > [180926.907906] [] ? __fput+0xe9/0x1ae >> > > [180926.913677] [] ? task_work_run+0x53/0x67 >> > > [180926.920031] [] ? do_notify_resume+0x79/0x8d >> > > [180926.926673] [] ? int_signal+0x12/0x17 >> > > [180926.932732] Code: 05 48 89 df ff d0 48 c7 c7 30 66 2d a0 e8 11 b0 >> > > 07 e1 48 89 df e8 72 25 00 00 48 8b 43 >> > > 78 a8 08 75 2a 48 8b 53 10 48 85 d2 75 04 <0f> 0b eb fe 48 8b 43 08 >> > > 48 89 02 a8 01 75 04 48 89 50 08 48 be >> > > [180926.954788] RIP [] destroy_conntrack+0x55/0xa9 >> > > [nf_conntrack] >> > > [180926.963217] RSP >> > > [180926.967700] ---[ end trace 54a660a52afd5820 ]--- >> > > [180926.973038] Kernel panic - not syncing: Fatal exception in interrupt >> > > >> > > --- >> > > Ian Applegate >> > > CloudFlare >> > > -- >> > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> > > the body of a message to majordomo@vger.kernel.org >> > > More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > Please read the FAQ at http://www.tux.org/lkml/ >> > >> > -- >> > Regards/Gruss, >> > Boris. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/