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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A725DC433FE for ; Wed, 23 Nov 2022 02:33:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234729AbiKWCdq (ORCPT ); Tue, 22 Nov 2022 21:33:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235119AbiKWCdm (ORCPT ); Tue, 22 Nov 2022 21:33:42 -0500 Received: from mail-io1-f69.google.com (mail-io1-f69.google.com [209.85.166.69]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A38145E3D0 for ; Tue, 22 Nov 2022 18:33:40 -0800 (PST) Received: by mail-io1-f69.google.com with SMTP id c20-20020a5d9754000000b006dbd4e6a5abso1861593ioo.17 for ; Tue, 22 Nov 2022 18:33:40 -0800 (PST) X-Google-DKIM-Signature: v=1; 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charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzbot has found a reproducer for the following issue on: HEAD commit: eb7081409f94 Linux 6.1-rc6 git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=155d6d45880000 kernel config: https://syzkaller.appspot.com/x/.config?x=8cdf448d3b35234 dashboard link: https://syzkaller.appspot.com/bug?extid=1047e42179f502f2b0a2 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1167648d880000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1562d6c5880000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/4a019f55c517/disk-eb708140.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/eb36e890aa8b/vmlinux-eb708140.xz kernel image: https://storage.googleapis.com/syzbot-assets/feee2c23ec64/bzImage-eb708140.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/aa387a5f9eda/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1047e42179f502f2b0a2@syzkaller.appspotmail.com REISERFS (device loop0): Using tea hash to sort names REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage. ====================================================== WARNING: possible circular locking dependency detected 6.1.0-rc6-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor139/3633 is trying to acquire lock: ffff888026b18460 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write_file+0x5a/0x1f0 fs/namespace.c:437 but task is already holding lock: ffff88801f89c090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x77/0xd0 fs/reiserfs/lock.c:27 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sbi->lock){+.+.}-{3:3}: lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668 __mutex_lock_common+0x1bd/0x26e0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 reiserfs_write_lock+0x77/0xd0 fs/reiserfs/lock.c:27 reiserfs_lookup+0x147/0x490 fs/reiserfs/namei.c:364 __lookup_slow+0x266/0x3a0 fs/namei.c:1685 lookup_one_len+0x430/0x690 fs/namei.c:2711 reiserfs_lookup_privroot+0x85/0x1e0 fs/reiserfs/xattr.c:973 reiserfs_fill_super+0x2071/0x24a0 fs/reiserfs/super.c:2174 mount_bdev+0x26c/0x3a0 fs/super.c:1401 legacy_get_tree+0xea/0x180 fs/fs_context.c:610 vfs_get_tree+0x88/0x270 fs/super.c:1531 do_new_mount+0x289/0xad0 fs/namespace.c:3040 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount+0x2d3/0x3c0 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&type->i_mutex_dir_key#6){+.+.}-{3:3}: lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668 down_write+0x9c/0x270 kernel/locking/rwsem.c:1562 inode_lock include/linux/fs.h:756 [inline] open_last_lookups fs/namei.c:3478 [inline] path_openat+0x7b9/0x2df0 fs/namei.c:3710 do_filp_open+0x264/0x4f0 fs/namei.c:3740 do_sys_openat2+0x124/0x4e0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_creat fs/open.c:1402 [inline] __se_sys_creat fs/open.c:1396 [inline] __x64_sys_creat+0x11f/0x160 fs/open.c:1396 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (sb_writers#9){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain+0x1898/0x6ae0 kernel/locking/lockdep.c:3831 __lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055 lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1826 [inline] sb_start_write+0x4d/0x1a0 include/linux/fs.h:1901 mnt_want_write_file+0x5a/0x1f0 fs/namespace.c:437 reiserfs_ioctl+0x16e/0x340 fs/reiserfs/ioctl.c:103 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: sb_writers#9 --> &type->i_mutex_dir_key#6 --> &sbi->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sbi->lock); lock(&type->i_mutex_dir_key#6); lock(&sbi->lock); lock(sb_writers#9); *** DEADLOCK *** 1 lock held by syz-executor139/3633: #0: ffff88801f89c090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x77/0xd0 fs/reiserfs/lock.c:27 stack backtrace: CPU: 1 PID: 3633 Comm: syz-executor139 Not tainted 6.1.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106 check_noncircular+0x2cc/0x390 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain+0x1898/0x6ae0 kernel/locking/lockdep.c:3831 __lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055 lock_acquire+0x182/0x3c0 kernel/locking/lockdep.c:5668 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1826 [inline] sb_start_write+0x4d/0x1a0 include/linux/fs.h:1901 mnt_want_write_file+0x5a/0x1f0 fs/namespace.c:437 reiserfs_ioctl+0x16e/0x340 fs/reiserfs/ioctl.c:103 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f9c2c672829 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffffe9d1ea8 EFLAGS: