====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc5-syzkaller-00234-g8cb1f10d8c4b #0 Not tainted ------------------------------------------------------ syz-executor.1/14620 is trying to acquire lock: ffff8880680e00e0 (&type->s_umount_key#25){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] ffff8880680e00e0 (&type->s_umount_key#25){++++}-{3:3}, at: super_lock+0x23c/0x380 fs/super.c:117 but task is already holding lock: ffff88804272d188 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] ffff88804272d188 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:502 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&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_check_media_change block/disk-events.c:284 [inline] disk_check_media_change+0x204/0x2b0 block/disk-events.c:275 sr_block_open+0xe1/0x260 drivers/scsi/sr.c:497 blkdev_get_whole+0x93/0x2c0 block/bdev.c:640 blkdev_get_by_dev.part.0+0x211/0xb20 block/bdev.c:795 blkdev_get_by_dev+0x75/0x80 block/bdev.c:829 blkdev_open+0x112/0x380 block/fops.c:589 do_dentry_open+0x88b/0x1730 fs/open.c:929 do_open fs/namei.c:3639 [inline] path_openat+0x19af/0x29c0 fs/namei.c:3796 do_filp_open+0x1de/0x430 fs/namei.c:3823 do_sys_openat2+0x176/0x1e0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1448 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 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 blkdev_get_by_dev.part.0+0x4f0/0xb20 block/bdev.c:786 blkdev_get_by_dev+0x75/0x80 block/bdev.c:829 journal_init_dev fs/reiserfs/journal.c:2626 [inline] journal_init+0xbb8/0x6470 fs/reiserfs/journal.c:2786 reiserfs_fill_super+0xcc6/0x3150 fs/reiserfs/super.c:2022 mount_bdev+0x1f3/0x2e0 fs/super.c:1629 legacy_get_tree+0x109/0x220 fs/fs_context.c:638 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] __ia32_sys_mount+0x291/0x310 fs/namespace.c:3861 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 -> #0 (&type->s_umount_key#25){++++}-{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 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 compat_blkdev_ioctl+0x262/0x7c0 block/ioctl.c:684 __do_compat_sys_ioctl+0x2bf/0x330 fs/ioctl.c:972 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 other info that might help us debug this: Chain exists of: &type->s_umount_key#25 --> &disk->open_mutex --> &bdev->bd_holder_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bdev->bd_holder_lock); lock(&disk->open_mutex); lock(&bdev->bd_holder_lock); rlock(&type->s_umount_key#25); *** DEADLOCK *** 1 lock held by syz-executor.1/14620: #0: ffff88804272d188 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] #0: ffff88804272d188 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:502 stack backtrace: CPU: 3 PID: 14620 Comm: syz-executor.1 Not tainted 6.6.0-rc5-syzkaller-00234-g8cb1f10d8c4b #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __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 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 compat_blkdev_ioctl+0x262/0x7c0 block/ioctl.c:684 __do_compat_sys_ioctl+0x2bf/0x330 fs/ioctl.c:972 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f45579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f405ac EFLAGS: 00000292 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000001261 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi