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 D88ADC76196 for ; Tue, 11 Apr 2023 06:54:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230501AbjDKGyP (ORCPT ); Tue, 11 Apr 2023 02:54:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43326 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230315AbjDKGyE (ORCPT ); Tue, 11 Apr 2023 02:54:04 -0400 Received: from mail-io1-f77.google.com (mail-io1-f77.google.com [209.85.166.77]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BFFB12D6B for ; Mon, 10 Apr 2023 23:53:46 -0700 (PDT) Received: by mail-io1-f77.google.com with SMTP id r14-20020a5e950e000000b0074cc9aba965so4922824ioj.11 for ; Mon, 10 Apr 2023 23:53:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1681196026; x=1683788026; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=yjfsXRlkEt9BMh+Ls8OP9AtDqH9PnXX74RZjpl1iflk=; b=Nfk7cnk7XU7HgDpDAce6BBcdUbqD69tcc58wqh786zHvGZpAsez+4o0xJ6C7asSZEM FxMiBNG94e7AQjiETgklTCP5wtjMUY8g90OacDW7toAaUuhQOsc9Z+fYvWwaQwFDsEQJ hZNAZ+2BuKxDs2NeXB0djAWzoO6Codds2c1OkfUwkRNu48pbY7i1dCl3oBOU5rOHV9iV 76W31OODAgSf9gGjAYiYcdmm2gQGEW6xvLlysaVno3OxlNDy2yPptrrppMGQHfdxDt8S Nr2O4+uty5Q+d6M0wB7/RM/sEfGDOEZ2uiwcWo2yepDqiQ3u/8Mv9McnjpiLTn0DxMpg oFcw== X-Gm-Message-State: AAQBX9dcAWlVANJvKRsFKQUZAOon0/TfTiBysLljriW9qywjv+Hbl5S5 BjXOStscLbzxIqzgooQqgcdtPhAcPCkGuBlfjZ58uwscBBl4 X-Google-Smtp-Source: AKy350aMIDRPsi0/gD3o1b/CgK2Nz0VIcM4ypkAi64sp6tgY2HHOVM5eQVductsNrk+6/lC5p71oZ5gmdXT8UeblyQxZS52w5Gr+ MIME-Version: 1.0 X-Received: by 2002:a6b:dc13:0:b0:745:4154:b571 with SMTP id s19-20020a6bdc13000000b007454154b571mr5119982ioc.3.1681196026048; Mon, 10 Apr 2023 23:53:46 -0700 (PDT) Date: Mon, 10 Apr 2023 23:53:46 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000ee3a3005f909f30a@google.com> Subject: [syzbot] [fs?] possible deadlock in sys_quotactl_fd From: syzbot To: jack@suse.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: 76f598ba7d8e Merge tag 'for-linus' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13965b21c80000 kernel config: https://syzkaller.appspot.com/x/.config?x=5666fa6aca264e42 dashboard link: https://syzkaller.appspot.com/bug?extid=aacb82fca60873422114 compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/1f01c9748997/disk-76f598ba.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b3afb4fc86b9/vmlinux-76f598ba.xz kernel image: https://storage.googleapis.com/syzbot-assets/8908040d7a31/bzImage-76f598ba.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+aacb82fca60873422114@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.3.0-rc5-syzkaller-00022-g76f598ba7d8e #0 Not tainted ------------------------------------------------------ syz-executor.0/17940 is trying to acquire lock: ffff88802a89e0e0 (&type->s_umount_key#31){++++}-{3:3}, at: __do_sys_quotactl_fd fs/quota/quota.c:999 [inline] ffff88802a89e0e0 (&type->s_umount_key#31){++++}-{3:3}, at: __se_sys_quotactl_fd+0x2fb/0x440 fs/quota/quota.c:972 but task is already holding lock: ffff88802a89e460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:394 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sb_writers#4){.+.+}-{0:0}: lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1477 [inline] sb_start_write include/linux/fs.h:1552 [inline] write_mmp_block+0xe5/0x930 fs/ext4/mmp.c:50 ext4_multi_mount_protect+0x364/0x990 fs/ext4/mmp.c:343 __ext4_remount fs/ext4/super.c:6543 [inline] ext4_reconfigure+0x29a8/0x3280 fs/ext4/super.c:6642 reconfigure_super+0x3c9/0x7c0 fs/super.c:956 vfs_fsconfig_locked fs/fsopen.c:254 [inline] __do_sys_fsconfig fs/fsopen.c:439 [inline] __se_sys_fsconfig+0xa29/0xf70 fs/fsopen.c:314 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&type->s_umount_key#31){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056 lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669 down_read+0x3d/0x50 kernel/locking/rwsem.c:1520 __do_sys_quotactl_fd fs/quota/quota.c:999 [inline] __se_sys_quotactl_fd+0x2fb/0x440 fs/quota/quota.c:972 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_writers#4); lock(&type->s_umount_key#31); lock(sb_writers#4); lock(&type->s_umount_key#31); *** DEADLOCK *** 1 lock held by syz-executor.0/17940: #0: ffff88802a89e460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:394 stack backtrace: CPU: 0 PID: 17940 Comm: syz-executor.0 Not tainted 6.3.0-rc5-syzkaller-00022-g76f598ba7d8e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2fe/0x3b0 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056 lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669 down_read+0x3d/0x50 kernel/locking/rwsem.c:1520 __do_sys_quotactl_fd fs/quota/quota.c:999 [inline] __se_sys_quotactl_fd+0x2fb/0x440 fs/quota/quota.c:972 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f3c2aa8c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3c2b826168 EFLAGS: 00000246 ORIG_RAX: 00000000000001bb RAX: ffffffffffffffda RBX: 00007f3c2ababf80 RCX: 00007f3c2aa8c169 RDX: ffffffffffffffff RSI: ffffffff80000601 RDI: 0000000000000003 RBP: 00007f3c2aae7ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000200024c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd71f38adf R14: 00007f3c2b826300 R15: 0000000000022000 --- This report is generated by a bot. 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