Hello, syzbot found the following issue on: HEAD commit: 401644852d0b Merge tag 'fs_for_v6.6-rc6' of git://git.kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1516d9c1680000 kernel config: https://syzkaller.appspot.com/x/.config?x=1531f6ad09decf37 dashboard link: https://syzkaller.appspot.com/bug?extid=0c538bd7f64c3c6e9a3c compiler: gcc (Debian 12.2.0-14) 12.2.0, 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/f214cbf53142/disk-40164485.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c07186eb3504/vmlinux-40164485.xz kernel image: https://storage.googleapis.com/syzbot-assets/3b8af11497b6/bzImage-40164485.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0c538bd7f64c3c6e9a3c@xxxxxxxxxxxxxxxxxxxxxxxxx EXT4-fs (loop4): external journal device major/minor numbers have changed EXT4-fs (loop4): external journal has bad superblock ====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc5-syzkaller-00072-g401644852d0b #0 Not tainted ------------------------------------------------------ syz-executor.4/13442 is trying to acquire lock: ffff88801c9eb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xb0/0x8e0 block/bdev.c:884 but task is already holding lock: ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_get_journal_blkdev fs/ext4/super.c:5861 [inline] ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_open_dev_journal fs/ext4/super.c:5933 [inline] ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_load_journal fs/ext4/super.c:5996 [inline] ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_load_and_init_journal+0x949/0x28f0 fs/ext4/super.c:4906 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&type->s_umount_key#32){++++}-{3:3}: down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x23c/0x380 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0x94/0x1b0 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x1550/0x1ce0 block/ioctl.c:502 blkdev_ioctl+0x249/0x770 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&bdev->bd_holder_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 bdev_mark_dead+0x25/0x230 block/bdev.c:961 disk_force_media_change+0x51/0x80 block/disk-events.c:302 __loop_clr_fd+0x3ab/0x8f0 drivers/block/loop.c:1174 lo_release+0x188/0x1c0 drivers/block/loop.c:1743 blkdev_put_whole+0xa5/0xe0 block/bdev.c:663 blkdev_put+0x40f/0x8e0 block/bdev.c:898 kill_block_super+0x58/0x70 fs/super.c:1649 exfat_kill_sb+0x3b/0xb0 fs/exfat/super.c:771 deactivate_locked_super+0x9a/0x170 fs/super.c:481 deactivate_super+0xde/0x100 fs/super.c:514 cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254 task_work_run+0x14d/0x240 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x215/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&disk->open_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 blkdev_put+0xb0/0x8e0 block/bdev.c:884 ext4_get_journal_blkdev fs/ext4/super.c:5920 [inline] ext4_open_dev_journal fs/ext4/super.c:5933 [inline] ext4_load_journal fs/ext4/super.c:5996 [inline] ext4_load_and_init_journal+0x1deb/0x28f0 fs/ext4/super.c:4906 __ext4_fill_super fs/ext4/super.c:5374 [inline] ext4_fill_super+0x8c4b/0xad30 fs/ext4/super.c:5703 get_tree_bdev+0x3b5/0x650 fs/super.c:1577 vfs_get_tree+0x8c/0x370 fs/super.c:1750 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &disk->open_mutex --> &bdev->bd_holder_lock --> &type->s_umount_key#32 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&type->s_umount_key#32); lock(&bdev->bd_holder_lock); lock(&type->s_umount_key#32); lock(&disk->open_mutex); *** DEADLOCK *** 1 lock held by syz-executor.4/13442: #0: ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_get_journal_blkdev fs/ext4/super.c:5861 [inline] #0: ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_open_dev_journal fs/ext4/super.c:5933 [inline] #0: ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_load_journal fs/ext4/super.c:5996 [inline] #0: ffff88807adce0e0 (&type->s_umount_key#32){++++}-{3:3}, at: ext4_load_and_init_journal+0x949/0x28f0 fs/ext4/super.c:4906 stack backtrace: CPU: 0 PID: 13442 Comm: syz-executor.4 Not tainted 6.6.0-rc5-syzkaller-00072-g401644852d0b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 blkdev_put+0xb0/0x8e0 block/bdev.c:884 ext4_get_journal_blkdev fs/ext4/super.c:5920 [inline] ext4_open_dev_journal fs/ext4/super.c:5933 [inline] ext4_load_journal fs/ext4/super.c:5996 [inline] ext4_load_and_init_journal+0x1deb/0x28f0 fs/ext4/super.c:4906 __ext4_fill_super fs/ext4/super.c:5374 [inline] ext4_fill_super+0x8c4b/0xad30 fs/ext4/super.c:5703 get_tree_bdev+0x3b5/0x650 fs/super.c:1577 vfs_get_tree+0x8c/0x370 fs/super.c:1750 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fba0307e1ea Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fba03d12ee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fba03d12f80 RCX: 00007fba0307e1ea RDX: 0000000020000000 RSI: 0000000020000500 RDI: 00007fba03d12f40 RBP: 0000000020000000 R08: 00007fba03d12f80 R09: 0000000000004503 R10: 0000000000004503 R11: 0000000000000202 R12: 0000000020000500 R13: 00007fba03d12f40 R14: 00000000000004c1 R15: 000000000000002c </TASK> --- This report 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@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
