From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756261AbcHXOaA (ORCPT ); Wed, 24 Aug 2016 10:30:00 -0400 Received: from mail-wm0-f49.google.com ([74.125.82.49]:35977 "EHLO mail-wm0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754440AbcHXO35 (ORCPT ); Wed, 24 Aug 2016 10:29:57 -0400 To: mszeredi@redhat.com Cc: "Linux-Kernel@Vger. Kernel. Org" , netdev@vger.kernel.org From: Nikolay Borisov Subject: kernel BUG at net/unix/garbage.c:149!" Message-ID: <57BDAE06.1040400@kyup.com> Date: Wed, 24 Aug 2016 17:24:06 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, I hit the following BUG: [1851513.239831] ------------[ cut here ]------------ [1851513.240079] kernel BUG at net/unix/garbage.c:149! [1851513.240313] invalid opcode: 0000 [#1] SMP [1851513.248320] CPU: 37 PID: 11683 Comm: nginx Tainted: G O 4.4.14-clouder3 #26 [1851513.248719] Hardware name: Supermicro X10DRi/X10DRi, BIOS 1.1 04/14/2015 [1851513.248966] task: ffff883b0f6f0000 ti: ffff880189cf0000 task.ti: ffff880189cf0000 [1851513.249361] RIP: 0010:[] [] unix_notinflight+0x8d/0x90 [1851513.249846] RSP: 0018:ffff880189cf3cf8 EFLAGS: 00010246 [1851513.250082] RAX: ffff883b05491968 RBX: ffff883b05491680 RCX: ffff8807f9967330 [1851513.250476] RDX: 0000000000000001 RSI: ffff882e6d8bae00 RDI: ffffffff82073f10 [1851513.250886] RBP: ffff880189cf3d08 R08: ffff880cbc70e200 R09: 0000000180200001 [1851513.251280] R10: ffff883fff3b9dc0 R11: ffffea0032f1c380 R12: ffff883fbaf50000 [1851513.251674] R13: ffffffff815f6354 R14: ffff881a7c77b140 R15: ffff881a7c7792c0 [1851513.252083] FS: 00007f4f19573720(0000) GS:ffff883fff3a0000(0000) knlGS:0000000000000000 [1851513.252481] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1851513.252717] CR2: 00000000013062d8 CR3: 0000001712f32000 CR4: 00000000001406e0 [1851513.253116] Stack: [1851513.253345] 00000000ffffffff ffff880189cf3d40 ffff880189cf3d28 ffffffff815f4383 [1851513.254022] ffff8839ee11a800 ffff8839ee11a800 ffff880189cf3d60 ffffffff815f53b8 [1851513.254685] 0000000000000000 ffff883406788de0 0000000000000000 0000000000000000 [1851513.255360] Call Trace: [1851513.255594] [] unix_detach_fds.isra.19+0x43/0x50 [1851513.255851] [] unix_destruct_scm+0x48/0x80 [1851513.256090] [] skb_release_head_state+0x4f/0xb0 [1851513.256328] [] skb_release_all+0x12/0x30 [1851513.256564] [] kfree_skb+0x32/0xa0 [1851513.256810] [] unix_release_sock+0x1e4/0x2c0 [1851513.257046] [] unix_release+0x20/0x30 [1851513.257284] [] sock_release+0x1f/0x80 [1851513.257521] [] sock_close+0x12/0x20 [1851513.257769] [] __fput+0xea/0x1f0 [1851513.258005] [] ____fput+0xe/0x10 [1851513.258244] [] task_work_run+0x7f/0xb0 [1851513.258488] [] exit_to_usermode_loop+0xc0/0xd0 [1851513.258728] [] syscall_return_slowpath+0x80/0xf0 [1851513.258983] [] int_ret_from_sys_call+0x25/0x9f [1851513.259222] Code: 7e 5b 41 5c 5d c3 48 8b 8b e8 02 00 00 48 8b 93 f0 02 00 00 48 89 51 08 48 89 0a 48 89 83 e8 02 00 00 48 89 83 f0 02 00 00 eb b8 <0f> 0b 90 0f 1f 44 00 00 55 48 c7 c7 10 3f 07 82 48 89 e5 41 54 [1851513.268473] RIP [] unix_notinflight+0x8d/0x90 [1851513.268793] RSP That's essentially BUG_ON(list_empty(&u->link)); I see that all the code involving the ->link member hasn't really been touched since it was introduced in 2007. So this must be a latent bug. This is the first time I've observed it. The state of the struct unix_sock can be found here http://sprunge.us/WCMW . Evidently, there are no inflight sockets. Regards, Nikolay