[ OK ] Listening on Load/Save RF Kill Switch Status /dev/rfkill Watch. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... Debian GNU/Linux 9 syzkaller ttyS0 syzkaller login: [ 171.659894][ T8423] cron (8423) used greatest stack depth: 22744 bytes left Warning: Permanently added '10.128.1.57' (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 [ 191.520668][ T8432] [ 191.523134][ T8432] ====================================================== [ 191.530134][ T8432] WARNING: possible circular locking dependency detected [ 191.537136][ T8432] 5.13.0-syzkaller #0 Not tainted [ 191.542143][ T8432] ------------------------------------------------------ [ 191.549141][ T8432] syz-executor762/8432 is trying to acquire lock: [ 191.555888][ T8432] ffffffff8cc7cba8 (loop_ctl_mutex){+.+.}-{3:3}, at: loop_probe+0xc7/0x150 [ 191.564513][ T8432] [ 191.564513][ T8432] but task is already holding lock: [ 191.571888][ T8432] ffffffff8c9e9de8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x25/0x1d0 [ 191.581364][ T8432] [ 191.581364][ T8432] which lock already depends on the new lock. [ 191.581364][ T8432] [ 191.592012][ T8432] [ 191.592012][ T8432] the existing dependency chain (in reverse order) is: [ 191.601012][ T8432] [ 191.601012][ T8432] -> #3 (major_names_lock){+.+.}-{3:3}: [ 191.608731][ T8432] __mutex_lock+0x12a/0x10a0 [ 191.613962][ T8432] __register_blkdev+0x2b/0x3e0 [ 191.619327][ T8432] register_mtd_blktrans+0x85/0x3c0 [ 191.625043][ T8432] do_one_initcall+0x103/0x650 [ 191.630324][ T8432] kernel_init_freeable+0x6b8/0x741 [ 191.636126][ T8432] kernel_init+0x1a/0x1d0 [ 191.640974][ T8432] ret_from_fork+0x1f/0x30 [ 191.646076][ T8432] [ 191.646076][ T8432] -> #2 (mtd_table_mutex){+.+.}-{3:3}: [ 191.653707][ T8432] __mutex_lock+0x12a/0x10a0 [ 191.658814][ T8432] blktrans_open+0x69/0x600 [ 191.663838][ T8432] blkdev_get_whole+0xa1/0x420 [ 191.669150][ T8432] blkdev_get_by_dev.part.0+0x30c/0xdd0 [ 191.675214][ T8432] blkdev_open+0x295/0x300 [ 191.680148][ T8432] do_dentry_open+0x4c8/0x11c0 [ 191.685424][ T8432] path_openat+0x1c0e/0x27e0 [ 191.690527][ T8432] do_filp_open+0x190/0x3d0 [ 191.695545][ T8432] do_sys_openat2+0x16d/0x420 [ 191.700734][ T8432] __x64_sys_open+0x119/0x1c0 [ 191.705930][ T8432] do_syscall_64+0x35/0xb0 [ 191.710949][ T8432] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 191.717364][ T8432] [ 191.717364][ T8432] -> #1 (&disk->open_mutex){+.+.}-{3:3}: [ 191.725171][ T8432] __mutex_lock+0x12a/0x10a0 [ 191.730276][ T8432] del_gendisk+0x8b/0x770 [ 191.735121][ T8432] loop_control_ioctl+0x3e7/0x480 [ 191.740668][ T8432] __x64_sys_ioctl+0x193/0x200 [ 191.745951][ T8432] do_syscall_64+0x35/0xb0 [ 191.750883][ T8432] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 191.757295][ T8432] [ 191.757295][ T8432] -> #0 (loop_ctl_mutex){+.+.}-{3:3}: [ 191.764929][ T8432] __lock_acquire+0x2a07/0x54a0 [ 191.770295][ T8432] lock_acquire+0x1ab/0x510 [ 191.775312][ T8432] __mutex_lock+0x12a/0x10a0 [ 191.780421][ T8432] loop_probe+0xc7/0x150 [ 191.785180][ T8432] blk_request_module+0x111/0x1d0 [ 191.790719][ T8432] blkdev_get_no_open+0x1d5/0x250 [ 191.796262][ T8432] blkdev_get_by_dev.part.0+0x25/0xdd0 [ 191.802236][ T8432] blkdev_open+0x295/0x300 [ 191.807169][ T8432] do_dentry_open+0x4c8/0x11c0 [ 191.812445][ T8432] path_openat+0x1c0e/0x27e0 [ 191.817547][ T8432] do_filp_open+0x190/0x3d0 [ 191.822568][ T8432] do_sys_openat2+0x16d/0x420 [ 191.827762][ T8432] __x64_sys_openat+0x13f/0x1f0 [ 191.833133][ T8432] do_syscall_64+0x35/0xb0 [ 191.838061][ T8432] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 191.844471][ T8432] [ 191.844471][ T8432] other info that might help us debug this: [ 191.844471][ T8432] [ 191.854682][ T8432] Chain exists of: [ 191.854682][ T8432] loop_ctl_mutex --> mtd_table_mutex --> major_names_lock [ 191.854682][ T8432] executing program [ 191.867705][ T8432] Possible unsafe locking scenario: [ 191.867705][ T8432] [ 191.875140][ T8432] CPU0 CPU1 [ 191.880488][ T8432] ---- ---- [ 191.885837][ T8432] lock(major_names_lock); [ 191.890327][ T8432] lock(mtd_table_mutex); [ 191.897247][ T8432] lock(major_names_lock); [ 191.904257][ T8432] lock(loop_ctl_mutex); [ 191.908572][ T8432] [ 191.908572][ T8432] *** DEADLOCK *** [ 191.908572][ T8432] [ 191.916700][ T8432] 1 lock held by syz-executor762/8432: executing program [ 191.922142][ T8432] #0: ffffffff8c9e9de8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x25/0x1d0 [ 191.932061][ T8432] [ 191.932061][ T8432] stack backtrace: [ 191.937935][ T8432] CPU: 1 PID: 8432 Comm: syz-executor762 Not tainted 5.13.0-syzkaller #0 [ 191.946336][ T8432] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 191.956379][ T8432] Call Trace: [ 191.959646][ T8432] dump_stack_lvl+0xcd/0x134 [ 191.964235][ T8432] check_noncircular+0x25f/0x2e0 executing program [ 191.969168][ T8432] ? print_circular_bug+0x1e0/0x1e0 [ 191.974365][ T8432] ? mark_lock+0xef/0x17b0 [ 191.978774][ T8432] ? kasan_save_stack+0x32/0x40 [ 191.983744][ T8432] ? kasan_save_stack+0x1b/0x40 [ 191.988593][ T8432] ? lockdep_lock+0xc6/0x200 [ 191.993179][ T8432] ? call_rcu_zapped+0xb0/0xb0 [ 191.997939][ T8432] ? do_filp_open+0x190/0x3d0 [ 192.002610][ T8432] ? __x64_sys_openat+0x13f/0x1f0 [ 192.007631][ T8432] __lock_acquire+0x2a07/0x54a0 [ 192.012482][ T8432] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 192.018458][ T8432] lock_acquire+0x1ab/0x510 [ 192.022954][ T8432] ? loop_probe+0xc7/0x150 [ 192.027370][ T8432] ? lock_release+0x720/0x720 [ 192.032042][ T8432] __mutex_lock+0x12a/0x10a0 [ 192.036630][ T8432] ? loop_probe+0xc7/0x150 [ 192.041042][ T8432] ? loop_probe+0xc7/0x150 [ 192.045455][ T8432] ? mutex_lock_io_nested+0xf00/0xf00 [ 192.050821][ T8432] ? __mutex_lock+0x5bf/0x10a0 [ 192.055581][ T8432] ? find_held_lock+0x2d/0x110 [ 192.060342][ T8432] ? blk_request_module+0x25/0x1d0 [ 192.065449][ T8432] ? ilookup+0xb3/0x230 [ 192.069602][ T8432] loop_probe+0xc7/0x150 [ 192.073867][ T8432] ? loop_control_ioctl+0x480/0x480 [ 192.079213][ T8432] ? find_inode_fast+0x16f/0x220 [ 192.084232][ T8432] ? do_raw_spin_unlock+0x171/0x230 [ 192.089464][ T8432] ? loop_control_ioctl+0x480/0x480 [ 192.094670][ T8432] blk_request_module+0x111/0x1d0 [ 192.099691][ T8432] blkdev_get_no_open+0x1d5/0x250 [ 192.104714][ T8432] blkdev_get_by_dev.part.0+0x25/0xdd0 [ 192.110170][ T8432] ? devcgroup_check_permission+0x1a8/0x420 [ 192.116057][ T8432] blkdev_open+0x295/0x300 executing program [ 192.120473][ T8432] do_dentry_open+0x4c8/0x11c0 [ 192.125258][ T8432] ? blkdev_get_by_dev+0x80/0x80 [ 192.130198][ T8432] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 192.136435][ T8432] ? may_open+0x1f6/0x420 [ 192.140939][ T8432] path_openat+0x1c0e/0x27e0 [ 192.145525][ T8432] ? path_lookupat+0x850/0x850 [ 192.150281][ T8432] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 192.156265][ T8432] do_filp_open+0x190/0x3d0 [ 192.160770][ T8432] ? may_open_dev+0xf0/0xf0 [ 192.165269][ T8432] ? do_raw_spin_lock+0x120/0x2b0 executing program [ 192.170297][ T8432] ? rwlock_bug.part.0+0x90/0x90 [ 192.175234][ T8432] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 192.181469][ T8432] ? _find_next_bit+0x1e3/0x260 [ 192.186323][ T8432] ? _raw_spin_unlock+0x24/0x40 [ 192.191175][ T8432] ? alloc_fd+0x2e6/0x660 [ 192.195503][ T8432] do_sys_openat2+0x16d/0x420 [ 192.200177][ T8432] ? build_open_flags+0x6f0/0x6f0 [ 192.205200][ T8432] ? __context_tracking_exit+0xb8/0xe0 [ 192.210657][ T8432] ? lock_downgrade+0x6e0/0x6e0 [ 192.215506][ T8432] ? lock_downgrade+0x6e0/0x6e0 [ 192.220350][ T8432] __x64_sys_openat+0x13f/0x1f0 [ 192.225200][ T8432] ? __ia32_sys_open+0x1c0/0x1c0 [ 192.230139][ T8432] ? syscall_enter_from_user_mode+0x21/0x70 [ 192.236032][ T8432] do_syscall_64+0x35/0xb0 [ 192.240706][ T8432] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 192.246599][ T8432] RIP: 0033:0x406ca7 [ 192.250486][ T8432] Code: 25 00 00 41 00 3d 00 00 41 00 74 47 64 8b 04 25 18 00 00 00 85 c0 75 6b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 95 00 00 00 48 8b 4c 24 28 64 48 2b 0c 25 executing program executing program [ 192.270173][ T8432] RSP: 002b:00007ffd50f910e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 [ 192.278723][ T8432] RAX: ffffffffffffffda RBX: 00007ffd50f911e0 RCX: 0000000000406ca7 [ 192.286686][ T8432] RDX: 0000000000000002 RSI: 00007ffd50f911e0 RDI: 00000000ffffff9c [ 192.294673][ T8432] RBP: 00007ffd50f911e0 R08: 0000000000000000 R09: 00007ffd50f90ff0 [ 192.302928][ T8432] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 [ 192.311141][ T8432] R13: 0000000000002113 R14: 00007ffd50f911d0 R15: 00007ffd50f91184 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 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 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 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 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 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 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 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 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