From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8899DC04AB1 for ; Thu, 9 May 2019 10:55:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 637A9216C4 for ; Thu, 9 May 2019 10:55:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726438AbfEIKzO (ORCPT ); Thu, 9 May 2019 06:55:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36680 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726415AbfEIKzO (ORCPT ); Thu, 9 May 2019 06:55:14 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B9F77C064293; Thu, 9 May 2019 10:55:13 +0000 (UTC) Received: from [172.16.176.1] (ovpn-112-5.rdu2.redhat.com [10.10.112.5]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8D6505DF4C; Thu, 9 May 2019 10:55:11 +0000 (UTC) From: "Benjamin Coddington" To: anna.schumaker@netapp.com Cc: linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, syzkaller-bugs@googlegroups.com, trond.myklebust@hammerspace.com, "Roberto Bergantinos Corpas" , syzbot Subject: Re: WARNING: locking bug in nfs_get_client Date: Thu, 09 May 2019 06:55:10 -0400 Message-ID: In-Reply-To: <000000000000c3e9dc0588695e22@google.com> References: <000000000000c3e9dc0588695e22@google.com> MIME-Version: 1.0 Content-Type: text/plain; format=flowed X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Thu, 09 May 2019 10:55:13 +0000 (UTC) Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org We need to return from nfs_match_client() while still holding the nfs_client_lock, or maybe fixed with ISERR_OR_NULL in nfs_match client(). Anna, would you like a patch to fix it, or can that commit be pulled out and fixed up at this point? Ben On 8 May 2019, at 20:17, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 31ccad9b Add linux-next specific files for 20190508 > git tree: linux-next > console output: > https://syzkaller.appspot.com/x/log.txt?x=1082d2aca00000 > kernel config: > https://syzkaller.appspot.com/x/.config?x=63cd766601c6c9fc > dashboard link: > https://syzkaller.appspot.com/bug?extid=228a82b263b5da91883d > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: > https://syzkaller.appspot.com/x/repro.syz?x=140fdce8a00000 > C reproducer: > https://syzkaller.appspot.com/x/repro.c?x=134dce02a00000 > > IMPORTANT: if you fix the bug, please add the following tag to the > commit: > Reported-by: syzbot+228a82b263b5da91883d@syzkaller.appspotmail.com > > ------------[ cut here ]------------ > DEBUG_LOCKS_WARN_ON(depth <= 0) > WARNING: CPU: 1 PID: 7948 at kernel/locking/lockdep.c:4052 > __lock_release kernel/locking/lockdep.c:4052 [inline] > WARNING: CPU: 1 PID: 7948 at kernel/locking/lockdep.c:4052 > lock_release+0x667/0xa00 kernel/locking/lockdep.c:4321 > Kernel panic - not syncing: panic_on_warn set ... > CPU: 1 PID: 7948 Comm: syz-executor561 Not tainted 5.1.0-next-20190508 > #3 > Hardware name: Google Google Compute Engine/Google Compute Engine, > BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x172/0x1f0 lib/dump_stack.c:113 > panic+0x2cb/0x75a kernel/panic.c:218 > __warn.cold+0x20/0x47 kernel/panic.c:575 > report_bug+0x263/0x2b0 lib/bug.c:186 > fixup_bug arch/x86/kernel/traps.c:179 [inline] > fixup_bug arch/x86/kernel/traps.c:174 [inline] > do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272 > do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291 > invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:972 > RIP: 0010:__lock_release kernel/locking/lockdep.c:4052 [inline] > RIP: 0010:lock_release+0x667/0xa00 kernel/locking/lockdep.c:4321 > Code: 0f 85 a0 03 00 00 8b 35 a7 02 09 08 85 f6 75 23 48 c7 c6 e0 57 > 6b 87 48 c7 c7 80 27 6b 87 4c 89 85 70 ff ff ff e8 37 7c eb ff <0f> 0b > 4c 8b 85 70 ff ff ff 4c 89 ea 4c 89 e6 4c 89 c7 e8 52 63 ff > RSP: 0018:ffff888095867730 EFLAGS: 00010082 > RAX: 0000000000000000 RBX: 1ffff11012b0ceec RCX: 0000000000000000 > RDX: 0000000000000000 RSI: ffffffff815b20c6 RDI: ffffed1012b0ced8 > RBP: ffff8880958677e8 R08: ffff88809a5b83c0 R09: fffffbfff1133071 > R10: fffffbfff1133070 R11: ffffffff88998383 R12: ffff888219eeb700 > R13: ffffffff821668ab R14: ffffffff8a45bd40 R15: ffff8880958677c0 > __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline] > _raw_spin_unlock+0x1b/0x50 kernel/locking/spinlock.c:183 > spin_unlock include/linux/spinlock.h:378 [inline] > nfs_get_client+0xc1b/0x1300 fs/nfs/client.c:412 > nfs_init_server+0x26f/0xea0 fs/nfs/client.c:675 > nfs_create_server+0x12b/0x6d0 fs/nfs/client.c:962 > nfs_try_mount+0x15a/0x910 fs/nfs/super.c:1882 > nfs_fs_mount+0x184a/0x2690 fs/nfs/super.c:2718 > legacy_get_tree+0x10a/0x220 fs/fs_context.c:665 > vfs_get_tree+0x93/0x3a0 fs/super.c:1476 > do_new_mount fs/namespace.c:2790 [inline] > do_mount+0x138c/0x1c00 fs/namespace.c:3110 > ksys_mount+0xdb/0x150 fs/namespace.c:3319 > __do_sys_mount fs/namespace.c:3333 [inline] > __se_sys_mount fs/namespace.c:3330 [inline] > __x64_sys_mount+0xbe/0x150 fs/namespace.c:3330 > do_syscall_64+0x103/0x670 arch/x86/entry/common.c:298 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x4467d9 > Code: e8 5c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 > 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d > 01 f0 ff ff 0f 83 0b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007f54c53e0db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 > RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 00000000004467d9 > RDX: 0000000020fb5ffc RSI: 0000000020343ff8 RDI: 0000000000000000 > RBP: 00000000006dbc30 R08: 000000002000a000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc3c > R13: 00007ffe22037e2f R14: 00007f54c53e19c0 R15: 20c49ba5e353f7cf > Kernel Offset: disabled > Rebooting in 86400 seconds.. > > > --- > This bug is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > syzbot can test patches for this bug, for details see: > https://goo.gl/tpsmEJ#testing-patches