From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f206.google.com (mail-il1-f206.google.com [209.85.166.206]) (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 7C22F1FA8E9 for ; Tue, 14 Jan 2025 18:59:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.206 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736881161; cv=none; b=JGk4nY8U0wfFuoT24vRQT3ixVBsJ3qddAKDWBm0RdPbaH3GJfspIbAzdjJ9OJJ+dVzeAFXy1sVsXUp5G3dQY3bNjZkferJZujOw6BtmU86emY3Mrty8wQ7tvpgt5YA/0YgFzqLHhl8kb2YppJeewm/8+UvRacE+HmmReMsKouRg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736881161; c=relaxed/simple; bh=7OUwih4VcDwr122iXQ2/6xTlUYlWTPgfM3VBTneOxOo=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=r0t9hK97+W7zV4OUL5CSsAJqnpjb579h6WYe3JJ7EfdYiwMeqBCup+0VDalIBFYTz/6VIjv23laIgAFCiUgxj+pDMF/e+MVtLqwhQMyuvn4OVyr7yZQ3POnbBuhkGEFZPb17qdpCjnZJa7gBvCYmihs1HlpHh8fx0EEpOo4a3Nw= 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=209.85.166.206 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-il1-f206.google.com with SMTP id e9e14a558f8ab-3ce81a40f5cso3862445ab.1 for ; Tue, 14 Jan 2025 10:59:19 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736881158; x=1737485958; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=yb9bDmDy6XP2nDBqyjlVHMR7vPvqvQRNWLadM59Lqk8=; b=mPnXhUz26fxTtvZCXpaowhHZN2QPln6jIR8RbSWvyz9HMZrlbNw4oJWSypDgr1NIVX MpWzAN9MFZTNGL626Tk2IvFHMKaxyHMj+XKC32vLKWUb7l/clk9rPUTxIs8tNk4ANIaj Qi06ehcjd6QdzjuCFi639p2H5JGjcau6S17k0uyGXONbkAeM36mD5Mr3sfAkOWH9tBET mRL9SQwIo4C6etqRT/UbI79VobXHcBVYsa+KAeUXpCnaofpMxC0sXEMl9xNF63mB/cZy B8EGqan9aFK2vvXC0UZXGl93xu4sMWFbmmWc5777fZlDYa8NnAhIot5pUHJ9Cnk7VUXW wz0w== X-Forwarded-Encrypted: i=1; AJvYcCV2LY902wlpTAxeb5IZmZqRabjqADiuMqSjOhM4/ULWiUa8mZiTuG2O17QsVaRrXUHKmZoPuu8+TyybZDc=@vger.kernel.org X-Gm-Message-State: AOJu0YxD/qbUyHwtBP9c5nwV2D+BxbzIRSs5Ddh475VFtNoiJs67iEVE L0EDW0pj09lx6/e6MycT3HyuFqm/vG2eqh77fFefrWAP9Sz1oMHiS+U0x3t2L3XnhKoF1VC1d4+ zq15n2NIuYw4O3f21NsPUh/FMVTTFwrGQKdtk+cfZOwFgQXCXnX522iw= X-Google-Smtp-Source: AGHT+IF+MJBJVAEltb6LAVu5fjEwJLG6uCEANkLO7q1t68/nY/8G5eUqXwbh1rT3bolIETdjSoyTM4AP136ho+QPZycKYf3HVcXt Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:20eb:b0:3ce:7fea:21d with SMTP id e9e14a558f8ab-3ce7fea0319mr20154805ab.21.1736881158699; Tue, 14 Jan 2025 10:59:18 -0800 (PST) Date: Tue, 14 Jan 2025 10:59:18 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6786b406.050a0220.216c54.00be.GAE@google.com> Subject: [syzbot] [kernfs?] possible deadlock in mnt_want_write (5) From: syzbot To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tj@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 2144da25584e Merge tag '6.13-rc6-ksmbd-server-fixes' of gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17a621df980000 kernel config: https://syzkaller.appspot.com/x/.config?x=7ac4cd61d548c1ef dashboard link: https://syzkaller.appspot.com/bug?extid=64625f8c24fc389ae96d compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/5a70c84e2a87/disk-2144da25.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/21d41f80a658/vmlinux-2144da25.xz kernel image: https://storage.googleapis.com/syzbot-assets/fa4e5651e223/bzImage-2144da25.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+64625f8c24fc389ae96d@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc6-syzkaller-00130-g2144da25584e #0 Not tainted ------------------------------------------------------ syz.5.330/7423 is trying to acquire lock: ffff88807ef2c420 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 but task is already holding lock: ffff88805a8a2418 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline] (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: open_last_lookups fs/namei.c:3745 [inline] (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: path_openat+0x89a/0x3590 fs/namei.c:3984 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1524 inode_lock_shared include/linux/fs.h:828 [inline] lookup_slow+0x45/0x70 fs/namei.c:1807 walk_component+0x2e1/0x410 fs/namei.c:2112 lookup_last fs/namei.c:2610 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2634 filename_lookup+0x2a3/0x670 fs/namei.c:2663 kern_path+0x35/0x50 fs/namei.c:2771 lookup_bdev+0xc5/0x290 block/bdev.c:1163 resume_store+0x1a0/0x710 kernel/power/hibernate.c:1242 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 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 -> #2 (&of->mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] do_splice+0xd68/0x18e0 fs/splice.c:1354 __do_splice fs/splice.c:1436 [inline] __do_sys_splice fs/splice.c:1639 [inline] __se_sys_splice+0x2e0/0x450 fs/splice.c:1621 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 -> #1 (&pipe->mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 iter_file_splice_write+0x330/0x1510 fs/splice.c:687 backing_file_splice_write+0x35a/0x570 fs/backing-file.c:315 ovl_splice_write+0x4b8/0x630 fs/overlayfs/file.c:440 do_splice_from fs/splice.c:941 [inline] do_splice+0xd68/0x18e0 fs/splice.c:1354 __do_splice fs/splice.c:1436 [inline] __do_sys_splice fs/splice.c:1639 [inline] __se_sys_splice+0x2e0/0x450 fs/splice.c:1621 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 (sb_writers#5){.+.+}-{0:0}: 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+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1725 [inline] sb_start_write+0x4d/0x1c0 include/linux/fs.h:1861 mnt_want_write+0x3f/0x90 fs/namespace.c:515 ovl_create_object+0x13a/0x3a0 fs/overlayfs/dir.c:656 lookup_open fs/namei.c:3649 [inline] open_last_lookups fs/namei.c:3748 [inline] path_openat+0x1c03/0x3590 fs/namei.c:3984 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1428 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 other info that might help us debug this: Chain exists of: sb_writers#5 --> &of->mutex --> &ovl_i_mutex_dir_key[depth] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ovl_i_mutex_dir_key[depth]); lock(&of->mutex); lock(&ovl_i_mutex_dir_key[depth]); rlock(sb_writers#5); *** DEADLOCK *** 2 locks held by syz.5.330/7423: #0: ffff888142bfa420 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88805a8a2418 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline] #1: ffff88805a8a2418 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: open_last_lookups fs/namei.c:3745 [inline] #1: ffff88805a8a2418 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: path_openat+0x89a/0x3590 fs/namei.c:3984 stack backtrace: CPU: 1 UID: 0 PID: 7423 Comm: syz.5.330 Not tainted 6.13.0-rc6-syzkaller-00130-g2144da25584e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1725 [inline] sb_start_write+0x4d/0x1c0 include/linux/fs.h:1861 mnt_want_write+0x3f/0x90 fs/namespace.c:515 ovl_create_object+0x13a/0x3a0 fs/overlayfs/dir.c:656 lookup_open fs/namei.c:3649 [inline] open_last_lookups fs/namei.c:3748 [inline] path_openat+0x1c03/0x3590 fs/namei.c:3984 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1428 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 RIP: 0033:0x7fd5a0185d29 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd5a1059038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fd5a0376080 RCX: 00007fd5a0185d29 RDX: 000000000000275a RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fd5a0201b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd5a0376080 R15: 00007ffc67faf488 --- This report is generated by a bot. 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