[ OK ] Started Getty on tty5. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.188' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 60.506823][ T8799] [ 60.509452][ T8799] ====================================================== [ 60.516701][ T8799] WARNING: possible circular locking dependency detected [ 60.524547][ T8799] 5.13.0-rc5-syzkaller #0 Not tainted [ 60.530716][ T8799] ------------------------------------------------------ [ 60.538014][ T8799] systemd-udevd/8799 is trying to acquire lock: [ 60.544232][ T8799] ffffffff8ca6de28 (loop_ctl_mutex){+.+.}-{3:3}, at: loop_probe+0xc7/0x150 [ 60.553026][ T8799] [ 60.553026][ T8799] but task is already holding lock: [ 60.560395][ T8799] ffffffff8c7e03a8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x25/0x1d0 [ 60.569856][ T8799] [ 60.569856][ T8799] which lock already depends on the new lock. [ 60.569856][ T8799] [ 60.580237][ T8799] [ 60.580237][ T8799] the existing dependency chain (in reverse order) is: [ 60.589232][ T8799] [ 60.589232][ T8799] -> #3 (major_names_lock){+.+.}-{3:3}: [ 60.596947][ T8799] __mutex_lock+0x139/0x10c0 [ 60.602752][ T8799] __register_blkdev+0x2b/0x3e0 [ 60.608359][ T8799] register_mtd_blktrans+0x85/0x3c0 [ 60.614241][ T8799] do_one_initcall+0x103/0x650 [ 60.619518][ T8799] kernel_init_freeable+0x6c4/0x74d [ 60.625249][ T8799] kernel_init+0xd/0x1b8 [ 60.630172][ T8799] ret_from_fork+0x1f/0x30 [ 60.635180][ T8799] [ 60.635180][ T8799] -> #2 (mtd_table_mutex){+.+.}-{3:3}: [ 60.642801][ T8799] __mutex_lock+0x139/0x10c0 [ 60.647895][ T8799] blktrans_open+0x69/0x600 [ 60.652903][ T8799] __blkdev_get+0x182/0xa30 [ 60.657913][ T8799] blkdev_get_by_dev+0x200/0x660 [ 60.663361][ T8799] blkdev_open+0x154/0x2b0 [ 60.668284][ T8799] do_dentry_open+0x4b9/0x11b0 [ 60.673557][ T8799] path_openat+0x1c0e/0x27e0 [ 60.678826][ T8799] do_filp_open+0x190/0x3d0 [ 60.683834][ T8799] do_sys_openat2+0x16d/0x420 [ 60.689017][ T8799] __x64_sys_open+0x119/0x1c0 [ 60.694197][ T8799] do_syscall_64+0x3a/0xb0 [ 60.699119][ T8799] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 60.705517][ T8799] [ 60.705517][ T8799] -> #1 (&bdev->bd_mutex){+.+.}-{3:3}: [ 60.713164][ T8799] __mutex_lock+0x139/0x10c0 [ 60.718264][ T8799] del_gendisk+0x24b/0xa00 [ 60.723211][ T8799] loop_control_ioctl+0x3e7/0x4c0 [ 60.728777][ T8799] __x64_sys_ioctl+0x193/0x200 [ 60.734046][ T8799] do_syscall_64+0x3a/0xb0 [ 60.738968][ T8799] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 60.745454][ T8799] [ 60.745454][ T8799] -> #0 (loop_ctl_mutex){+.+.}-{3:3}: [ 60.753248][ T8799] __lock_acquire+0x2a17/0x5230 [ 60.758608][ T8799] lock_acquire+0x1ab/0x740 [ 60.763622][ T8799] __mutex_lock+0x139/0x10c0 [ 60.768720][ T8799] loop_probe+0xc7/0x150 [ 60.773467][ T8799] blk_request_module+0x111/0x1d0 [ 60.778999][ T8799] blkdev_get_no_open+0x1d8/0x250 [ 60.784531][ T8799] blkdev_get_by_dev+0x76/0x660 [ 60.789888][ T8799] blkdev_open+0x154/0x2b0 [ 60.794813][ T8799] do_dentry_open+0x4b9/0x11b0 [ 60.800082][ T8799] path_openat+0x1c0e/0x27e0 [ 60.805180][ T8799] do_filp_open+0x190/0x3d0 [ 60.810193][ T8799] do_sys_openat2+0x16d/0x420 [ 60.815375][ T8799] __x64_sys_open+0x119/0x1c0 [ 60.820555][ T8799] do_syscall_64+0x3a/0xb0 [ 60.825481][ T8799] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 60.831885][ T8799] [ 60.831885][ T8799] other info that might help us debug this: [ 60.831885][ T8799] [ 60.842097][ T8799] Chain exists of: [ 60.842097][ T8799] loop_ctl_mutex --> mtd_table_mutex --> major_names_lock [ 60.842097][ T8799] [ 60.855149][ T8799] Possible unsafe locking scenario: [ 60.855149][ T8799] [ 60.862606][ T8799] CPU0 CPU1 [ 60.867950][ T8799] ---- ---- [ 60.873295][ T8799] lock(major_names_lock); [ 60.877780][ T8799] lock(mtd_table_mutex); [ 60.884698][ T8799] lock(major_names_lock); [ 60.891815][ T8799] lock(loop_ctl_mutex); [ 60.896125][ T8799] [ 60.896125][ T8799] *** DEADLOCK *** [ 60.896125][ T8799] [ 60.904246][ T8799] 1 lock held by systemd-udevd/8799: [ 60.909510][ T8799] #0: ffffffff8c7e03a8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x25/0x1d0 [ 60.919409][ T8799] [ 60.919409][ T8799] stack backtrace: [ 60.925452][ T8799] CPU: 0 PID: 8799 Comm: systemd-udevd Not tainted 5.13.0-rc5-syzkaller #0 [ 60.934023][ T8799] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.944059][ T8799] Call Trace: [ 60.947328][ T8799] dump_stack+0x141/0x1d7 [ 60.951651][ T8799] check_noncircular+0x25f/0x2e0 [ 60.956577][ T8799] ? print_circular_bug+0x1e0/0x1e0 [ 60.961903][ T8799] ? mark_lock+0xef/0x17b0 [ 60.966306][ T8799] ? lockdep_lock+0xc6/0x200 [ 60.970881][ T8799] ? call_rcu_zapped+0xb0/0xb0 [ 60.975641][ T8799] ? tomoyo_check_open_permission+0x172/0x380 [ 60.981691][ T8799] ? security_file_open+0x52/0x4f0 [ 60.986787][ T8799] __lock_acquire+0x2a17/0x5230 [ 60.991625][ T8799] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 60.997589][ T8799] lock_acquire+0x1ab/0x740 [ 61.002079][ T8799] ? loop_probe+0xc7/0x150 [ 61.006481][ T8799] ? lock_release+0x720/0x720 [ 61.011147][ T8799] __mutex_lock+0x139/0x10c0 [ 61.015843][ T8799] ? loop_probe+0xc7/0x150 [ 61.020248][ T8799] ? loop_probe+0xc7/0x150 [ 61.024653][ T8799] ? mutex_lock_io_nested+0xf20/0xf20 [ 61.030013][ T8799] ? __mutex_lock+0x5d5/0x10c0 [ 61.034762][ T8799] ? blk_request_module+0x25/0x1d0 [ 61.039863][ T8799] ? find_held_lock+0x2d/0x110 [ 61.044613][ T8799] ? mutex_lock_io_nested+0xf20/0xf20 [ 61.049972][ T8799] ? ilookup+0xb3/0x230 [ 61.054117][ T8799] loop_probe+0xc7/0x150 [ 61.058373][ T8799] ? loop_control_ioctl+0x4c0/0x4c0 [ 61.063588][ T8799] ? find_inode_fast+0x16f/0x220 [ 61.068516][ T8799] ? do_raw_spin_unlock+0x171/0x230 [ 61.073699][ T8799] ? loop_control_ioctl+0x4c0/0x4c0 [ 61.078884][ T8799] blk_request_module+0x111/0x1d0 [ 61.083896][ T8799] blkdev_get_no_open+0x1d8/0x250 [ 61.088909][ T8799] blkdev_get_by_dev+0x76/0x660 [ 61.093920][ T8799] blkdev_open+0x154/0x2b0 [ 61.098322][ T8799] do_dentry_open+0x4b9/0x11b0 [ 61.103099][ T8799] ? blkdev_get_by_dev+0x660/0x660 [ 61.108195][ T8799] ? may_open+0x1f6/0x420 [ 61.112622][ T8799] path_openat+0x1c0e/0x27e0 [ 61.117299][ T8799] ? path_lookupat+0x850/0x850 [ 61.122050][ T8799] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 61.128028][ T8799] do_filp_open+0x190/0x3d0 [ 61.132519][ T8799] ? may_open_dev+0xf0/0xf0 [ 61.137008][ T8799] ? do_raw_spin_lock+0x120/0x2b0 [ 61.142017][ T8799] ? rwlock_bug.part.0+0x90/0x90 [ 61.146939][ T8799] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 61.153170][ T8799] ? _find_next_bit+0x1e3/0x260 [ 61.158012][ T8799] ? _raw_spin_unlock+0x24/0x40 [ 61.162851][ T8799] ? alloc_fd+0x2e6/0x660 [ 61.167172][ T8799] do_sys_openat2+0x16d/0x420 [ 61.171844][ T8799] ? build_open_flags+0x6f0/0x6f0 [ 61.176854][ T8799] ? __context_tracking_exit+0xb8/0xe0 [ 61.182319][ T8799] __x64_sys_open+0x119/0x1c0 [ 61.186985][ T8799] ? do_sys_open+0x140/0x140 [ 61.191559][ T8799] ? __secure_computing+0x104/0x360 [ 61.196743][ T8799] do_syscall_64+0x3a/0xb0 [ 61.201146][ T8799] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 61.207027][ T8799] RIP: 0033:0x7f85958d8840 [ 61.211451][ T8799] Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 [ 61.231066][ T8799] RSP: 002b:00007fffb5dc5ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 [ 61.239462][ T8799] RAX: ffffffffffffffda RBX: 000055a668cd38f0 RCX: 00007f85958d8840 [ 61.247418][ T8799] RDX: 000055a6682aafe3 RSI: 00000000000a0800 RDI: 000055a668cd3830 [ 61.255374][ T8799] RBP: 00007fffb5dc5e60 R08: 000055a6682aa670 R09: 0000000000000010 [ 61.263358][ T8799] R10: 00007f8595652d70 R11: 0000000000000246 R12: 00007fffb5dc5db0 [ 61.271316][ T8799] R13: 000055a668cd5010 R14: 0000000000000003 R15: 000000000000000e 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