[info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 15.499622][ C1] random: crng init done [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.30' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 24.716085][ T12] usb 1-1: new high-speed USB device number 2 using dummy_hcd [ 24.956073][ T12] usb 1-1: Using ep0 maxpacket: 16 [ 25.076143][ T12] usb 1-1: config 0 has an invalid interface number: 133 but max is 0 [ 25.084376][ T12] usb 1-1: config 0 has no interface number 0 [ 25.090519][ T12] usb 1-1: New USB device found, idVendor=0841, idProduct=0001, bcdDevice=c5.d0 [ 25.099751][ T12] usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 [ 25.109025][ T12] usb 1-1: config 0 descriptor?? [ 25.147637][ T12] rio500 1-1:0.133: USB Rio found at address 2 [ 25.346360][ T1724] [ 25.348701][ T1724] ====================================================== [ 25.355696][ T1724] WARNING: possible circular locking dependency detected [ 25.362722][ T1724] 5.3.0-rc7+ #0 Not tainted [ 25.367189][ T1724] ------------------------------------------------------ [ 25.374175][ T1724] syz-executor071/1724 is trying to acquire lock: [ 25.380554][ T1724] 00000000f749c934 (rio500_mutex){+.+.}, at: open_rio+0x16/0xe0 [ 25.388162][ T1724] [ 25.388162][ T1724] but task is already holding lock: [ 25.395497][ T1724] 000000009c24ba51 (minor_rwsem){++++}, at: usb_open+0x23/0x270 [ 25.403101][ T1724] [ 25.403101][ T1724] which lock already depends on the new lock. [ 25.403101][ T1724] [ 25.413470][ T1724] [ 25.413470][ T1724] the existing dependency chain (in reverse order) is: [ 25.422479][ T1724] [ 25.422479][ T1724] -> #1 (minor_rwsem){++++}: [ 25.429216][ T1724] down_write+0x92/0x150 [ 25.433951][ T1724] usb_register_dev+0x131/0x670 [ 25.439290][ T1724] probe_rio.cold+0x53/0x237 [ 25.444371][ T1724] usb_probe_interface+0x305/0x7a0 [ 25.449970][ T1724] really_probe+0x281/0x6d0 [ 25.454964][ T1724] driver_probe_device+0x101/0x1b0 [ 25.460563][ T1724] __device_attach_driver+0x1c2/0x220 [ 25.466437][ T1724] bus_for_each_drv+0x162/0x1e0 [ 25.471779][ T1724] __device_attach+0x217/0x360 [ 25.477035][ T1724] bus_probe_device+0x1e4/0x290 [ 25.482386][ T1724] device_add+0xae6/0x16f0 [ 25.487300][ T1724] usb_set_configuration+0xdf6/0x1670 [ 25.493198][ T1724] generic_probe+0x9d/0xd5 [ 25.498105][ T1724] usb_probe_device+0x99/0x100 [ 25.503369][ T1724] really_probe+0x281/0x6d0 [ 25.508363][ T1724] driver_probe_device+0x101/0x1b0 [ 25.513969][ T1724] __device_attach_driver+0x1c2/0x220 [ 25.519831][ T1724] bus_for_each_drv+0x162/0x1e0 [ 25.525175][ T1724] __device_attach+0x217/0x360 [ 25.530429][ T1724] bus_probe_device+0x1e4/0x290 [ 25.535772][ T1724] device_add+0xae6/0x16f0 [ 25.540678][ T1724] usb_new_device.cold+0x6a4/0xe79 [ 25.546278][ T1724] hub_event+0x1b5c/0x3640 [ 25.551193][ T1724] process_one_work+0x92b/0x1530 [ 25.556634][ T1724] worker_thread+0x96/0xe20 [ 25.561633][ T1724] kthread+0x318/0x420 [ 25.566196][ T1724] ret_from_fork+0x24/0x30 [ 25.571109][ T1724] [ 25.571109][ T1724] -> #0 (rio500_mutex){+.+.}: [ 25.577935][ T1724] __lock_acquire+0x1f7c/0x3b50 [ 25.583275][ T1724] lock_acquire+0x127/0x320 [ 25.588265][ T1724] __mutex_lock+0x158/0x1360 [ 25.593343][ T1724] open_rio+0x16/0xe0 [ 25.597816][ T1724] usb_open+0x1df/0x270 [ 25.602464][ T1724] chrdev_open+0x219/0x5c0 [ 25.607370][ T1724] do_dentry_open+0x494/0x1120 [ 25.612623][ T1724] path_openat+0x1430/0x3f50 [ 25.617699][ T1724] do_filp_open+0x1a1/0x280 [ 25.622711][ T1724] do_sys_open+0x3c0/0x580 [ 25.627621][ T1724] do_syscall_64+0xb7/0x580 [ 25.632617][ T1724] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 25.638998][ T1724] [ 25.638998][ T1724] other info that might help us debug this: [ 25.638998][ T1724] [ 25.649206][ T1724] Possible unsafe locking scenario: [ 25.649206][ T1724] [ 25.656630][ T1724] CPU0 CPU1 [ 25.661976][ T1724] ---- ---- [ 25.667316][ T1724] lock(minor_rwsem); [ 25.671357][ T1724] lock(rio500_mutex); [ 25.678003][ T1724] lock(minor_rwsem); [ 25.684557][ T1724] lock(rio500_mutex); [ 25.688680][ T1724] [ 25.688680][ T1724] *** DEADLOCK *** [ 25.688680][ T1724] [ 25.696798][ T1724] 1 lock held by syz-executor071/1724: [ 25.702223][ T1724] #0: 000000009c24ba51 (minor_rwsem){++++}, at: usb_open+0x23/0x270 [ 25.710265][ T1724] [ 25.710265][ T1724] stack backtrace: [ 25.716143][ T1724] CPU: 0 PID: 1724 Comm: syz-executor071 Not tainted 5.3.0-rc7+ #0 [ 25.724001][ T1724] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.734027][ T1724] Call Trace: [ 25.737307][ T1724] dump_stack+0xca/0x13e [ 25.741524][ T1724] check_noncircular+0x345/0x3e0 [ 25.746442][ T1724] ? print_circular_bug+0x1b0/0x1b0 [ 25.751611][ T1724] ? graph_lock+0x80/0x180 [ 25.755994][ T1724] ? hlock_class+0x120/0x120 [ 25.760551][ T1724] ? mark_lock+0xbc/0x1130 [ 25.764947][ T1724] ? print_shortest_lock_dependencies+0x80/0x80 [ 25.771164][ T1724] __lock_acquire+0x1f7c/0x3b50 [ 25.775994][ T1724] ? mark_held_locks+0xe0/0xe0 [ 25.780727][ T1724] ? hlock_class+0x120/0x120 [ 25.785296][ T1724] ? find_first_zero_bit+0x94/0xb0 [ 25.790373][ T1724] lock_acquire+0x127/0x320 [ 25.794857][ T1724] ? open_rio+0x16/0xe0 [ 25.798986][ T1724] __mutex_lock+0x158/0x1360 [ 25.803544][ T1724] ? open_rio+0x16/0xe0 [ 25.807762][ T1724] ? open_rio+0x16/0xe0 [ 25.811886][ T1724] ? mutex_trylock+0x2c0/0x2c0 [ 25.816639][ T1724] ? lock_acquire+0x127/0x320 [ 25.821285][ T1724] ? usb_open+0x23/0x270 [ 25.825496][ T1724] ? down_read+0x113/0x3f0 [ 25.829880][ T1724] ? m_show+0x4f0/0x4f0 [ 25.834107][ T1724] ? down_read_killable+0x430/0x430 [ 25.839272][ T1724] ? probe_rio+0x70/0x70 [ 25.843483][ T1724] ? open_rio+0x16/0xe0 [ 25.847615][ T1724] open_rio+0x16/0xe0 [ 25.851567][ T1724] ? probe_rio+0x70/0x70 [ 25.855776][ T1724] usb_open+0x1df/0x270 [ 25.859900][ T1724] ? usb_devnode+0xa0/0xa0 [ 25.864289][ T1724] chrdev_open+0x219/0x5c0 [ 25.869717][ T1724] ? cdev_put.part.0+0x50/0x50 [ 25.874451][ T1724] do_dentry_open+0x494/0x1120 [ 25.879193][ T1724] ? cdev_put.part.0+0x50/0x50 [ 25.883925][ T1724] ? chmod_common+0x3c0/0x3c0 [ 25.888572][ T1724] ? inode_permission+0xbe/0x3a0 [ 25.893484][ T1724] path_openat+0x1430/0x3f50 [ 25.898043][ T1724] ? save_stack+0x1b/0x80 [ 25.902341][ T1724] ? do_sys_open+0x294/0x580 [ 25.906901][ T1724] ? do_syscall_64+0xb7/0x580 [ 25.911544][ T1724] ? path_lookupat.isra.0+0x8d0/0x8d0 [ 25.916883][ T1724] ? __lock_acquire+0x145e/0x3b50 [ 25.921877][ T1724] do_filp_open+0x1a1/0x280 [ 25.926346][ T1724] ? may_open_dev+0xf0/0xf0 [ 25.930842][ T1724] ? __alloc_fd+0x46d/0x600 [ 25.935325][ T1724] ? _raw_spin_unlock+0x1f/0x30 [ 25.940144][ T1724] ? __alloc_fd+0x46d/0x600 [ 25.944617][ T1724] do_sys_open+0x3c0/0x580 [ 25.949005][ T1724] ? filp_open+0x70/0x70 [ 25.953236][ T1724] ? switch_fpu_return+0x1c2/0x430 [ 25.958321][ T1724] ? hrtimer_nanosleep+0x510/0x510 [ 25.963398][ T1724] ? trace_hardirqs_off_caller+0x55/0x1e0 [ 25.969084][ T1724] do_syscall_64+0xb7/0x580 [ 25.973556][ T1724] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 25.979419][ T1724] RIP: 0033:0x401130 [ 25.983288][ T1724] Code: 01 f0 ff ff 0f 83 00 0b 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d 5d 0c 2d 00 00 75 14 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 d4 0a 00 00 c3 48 83 ec 08 e8 3a 00 00 00 [ 26.003119][ T1724] RSP: 002b:00007ffca0216788 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 [ 26.011498][ T1724] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000401130 [ 26.019439][ T1724] RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00007ffca02167a0 [ 26.027383][ T1724] RBP: 00000000006cb018 R08: 0000000000000000 R09: 000000000000000f [ 26.035323][ T1724] R10: 0000000000000064 R11: 0000000000000246 R12: 0000000000402090 [ 26.043263][ T1724] R13: 0000000000402120 R14: 0000000000000000 R15: 00