From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f69.google.com (mail-io1-f69.google.com [209.85.166.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5B866137E for ; Sun, 17 Nov 2024 01:25:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731806726; cv=none; b=lHAVTRqk/gch+x12UCiMQ8uoZJ6mj872nI/8GD0D0HAH9xgocR4U3ZMxGOxWD5hWOx7jcN6cIW8LPmy1ciJ+0eofwkXCxTB/eAY7RHJw+0nl2AQU7Bbj66s/18Jq3XCErJLO1PhirOa03fnwHQeVc7n2XBeL3uhWrMHefw5uLx0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731806726; c=relaxed/simple; bh=gtPVxxPW4PoI21b3gdNjKoJz+BVY9CMj1xfqOAcx6N8=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=WkLzEYo5M+XWliSm7eLsRLG5KfyCgwTZW1QiY+RUrkwkb6rcjTqp2TAEwRyUHTEriJh3Y2JQS5T90a22AIIKM/krry+B+ZBYujBYwv6pZkVtZ0UnOJ/NA1RrScRpzhsk3Bog75rk7DpALYzgBQJXUmkq0mM0HSzNAa0fAUWszl0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f69.google.com with SMTP id ca18e2360f4ac-83abb2b6d42so199851439f.3 for ; Sat, 16 Nov 2024 17:25:24 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1731806723; x=1732411523; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=G1ga9Foh74NctgQmJhdZFj8i06xTH41lukCFxYSYprM=; b=qM6cKWC+AAUpiGiWMEDc9/dfNmBmOYjIZpvQlxIR/ZLOg7N6gw6hTWS6ltbiKmABVY faAi/9SOj//qsOrKrooSwy/KwUpEY2o9M9ssx6yrPl18993g6lytDD+uHHAQNpJySi55 jCKy0oZDYNhMd5U5qXQHVD9vKnI31J0npsdy9sGitSQRwI7H5Fo5iKPny9vTmrw8N1Tk h7oII6AiAGU8rB1LXaSIZUv/9AGrZheWxYXFWoYNc2oilEKNVZiY2dlxImiU4SRr0bFE JHhOiiKXbA8yP690zzROX2/GpHGZHGJ6RG0b2RM9GkRcpQCp1HywaXWHqTsRfX+JjSIw DbJA== X-Forwarded-Encrypted: i=1; AJvYcCW3remVLaXLbGSPq5EA78ZEY/7WuBHTiYoW8QS0XOHmWEPfnU9aQqiMtOFoyfRLJFGhJOLiv5uz2ThNdbQ=@vger.kernel.org X-Gm-Message-State: AOJu0Yw2qdYLD4ph/bFqiILxRUxMg1NBG9Z8pHv03gMEkfia7WyLHfel 1OE3lXYnSnk8ZoK3JFkF5MudP+8TP9aYQv+hrjt07GdPe+FBDyMyw9wsvO3dLrPdMcxFJ6L42tG 4prUIOiPfNLKufayse4Ma+EuKv4qBcIMNMRVs6rhYAGksm0ybzOCor+Q= X-Google-Smtp-Source: AGHT+IFtiUrLXO7vesCVY4cJj4AioE4fjzZwhL0G4PlI05cb3OWi6E0rbbSZDcMUVNJP+OwFVXl4+/GOgrtapriEiYdamKeZtyos Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a92:ca4f:0:b0:3a7:1e4b:f32d with SMTP id e9e14a558f8ab-3a748079ecbmr74476985ab.17.1731806723647; Sat, 16 Nov 2024 17:25:23 -0800 (PST) Date: Sat, 16 Nov 2024 17:25:23 -0800 In-Reply-To: <00000000000093a1ca0621e8d336@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <67394603.050a0220.e1c64.000e.GAE@google.com> Subject: Re: [syzbot] [ocfs2?] possible deadlock in ocfs2_page_mkwrite From: syzbot To: jlbec@evilplan.org, joseph.qi@linux.alibaba.com, linux-kernel@vger.kernel.org, mark@fasheh.com, ocfs2-devel@lists.linux.dev, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" syzbot has found a reproducer for the following issue on: HEAD commit: b5a24181e461 Merge tag 'trace-ringbuffer-v6.12-rc7-2' of g.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=14ecd2c0580000 kernel config: https://syzkaller.appspot.com/x/.config?x=1503500c6f615d24 dashboard link: https://syzkaller.appspot.com/bug?extid=2e6495950edcf7fbfccf compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17f252e8580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12ecd2c0580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/048c0136cb21/disk-b5a24181.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5667b33e03d5/vmlinux-b5a24181.xz kernel image: https://storage.googleapis.com/syzbot-assets/1413f6952b55/bzImage-b5a24181.xz mounted in repro #1: https://storage.googleapis.com/syzbot-assets/2e0d55b52167/mount_0.gz mounted in repro #2: https://storage.googleapis.com/syzbot-assets/82e694655642/mount_7.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2e6495950edcf7fbfccf@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.12.0-rc7-syzkaller-00192-gb5a24181e461 #0 Not tainted ------------------------------------------------------ syz-executor420/5970 is trying to acquire lock: ffff88807839b120 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 but task is already holding lock: ffff88807c820518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3162 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults){.+.+}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1716 [inline] sb_start_pagefault include/linux/fs.h:1881 [inline] ocfs2_page_mkwrite+0x222/0xed0 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x198/0x480 mm/memory.c:3162 do_shared_fault mm/memory.c:5373 [inline] do_fault mm/memory.c:5435 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x11fa/0x6820 mm/memory.c:5766 __handle_mm_fault mm/memory.c:5909 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6077 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (&mm->mmap_lock){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __might_fault+0xc6/0x120 mm/memory.c:6716 _inline_copy_to_user include/linux/uaccess.h:192 [inline] _copy_to_user+0x2c/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:225 [inline] fiemap_fill_next_extent+0x235/0x410 fs/ioctl.c:145 ocfs2_fiemap_inline fs/ocfs2/extent_map.c:725 [inline] ocfs2_fiemap+0xc25/0xf80 fs/ocfs2/extent_map.c:762 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x198/0x480 mm/memory.c:3162 do_shared_fault mm/memory.c:5373 [inline] do_fault mm/memory.c:5435 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x11fa/0x6820 mm/memory.c:5766 __handle_mm_fault mm/memory.c:5909 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6077 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 other info that might help us debug this: Chain exists of: &ocfs2_file_ip_alloc_sem_key --> &mm->mmap_lock --> sb_pagefaults Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults); lock(&mm->mmap_lock); lock(sb_pagefaults); lock(&ocfs2_file_ip_alloc_sem_key); *** DEADLOCK *** 2 locks held by syz-executor420/5970: #0: ffff8880303d8198 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff8880303d8198 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6114 [inline] #0: ffff8880303d8198 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6174 #1: ffff88807c820518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3162 stack backtrace: CPU: 1 UID: 0 PID: 5970 Comm: syz-executor420 Not tainted 6.12.0-rc7-syzkaller-00192-gb5a24181e461 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x198/0x480 mm/memory.c:3162 do_shared_fault mm/memory.c:5373 [inline] do_fault mm/memory.c:5435 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x11fa/0x6820 mm/memory.c:5766 __handle_mm_fault mm/memory.c:5909 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6077 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f47ff734108 Code: 48 8b 35 23 50 0b 00 ba 01 cf 20 00 31 c0 bf 4d 00 00 00 e8 5a 46 03 00 66 0f 6f 05 f2 66 08 00 48 b8 2e 2f 66 69 6c 65 31 00 04 25 c0 01 00 20 74 72 65 65 48 89 04 25 00 00 00 20 ba 03 00 RSP: 002b:00007ffdcacffc30 EFLAGS: 00010217 RAX: 0031656c69662f2e RBX: 696c6e695f78616d RCX: 00007f47ff768769 RDX: 00007f47ff768769 RSI: 000000000020cf01 RDI: 0000000000000006 RBP: 6569727261626f6e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000006 R11: 0000000000000246 R12: 00007ffdcacffc5c R13: 000000000000002d R14: 431bde82d7b634db R15: 00007ffdcacffc90 --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.