[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.508669] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 25.460180] random: sshd: uninitialized urandom read (32 bytes read) [ 25.891169] random: sshd: uninitialized urandom read (32 bytes read) [ 26.651933] random: sshd: uninitialized urandom read (32 bytes read) [ 26.802598] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.26' (ECDSA) to the list of known hosts. [ 32.222077] random: sshd: uninitialized urandom read (32 bytes read) 2018/06/06 12:01:29 parsed 1 programs [ 33.217364] random: cc1: uninitialized urandom read (8 bytes read) 2018/06/06 12:01:31 executed programs: 0 [ 34.446903] IPVS: ftp: loaded support on port[0] = 21 [ 34.572726] bridge0: port 1(bridge_slave_0) entered blocking state [ 34.579169] bridge0: port 1(bridge_slave_0) entered disabled state [ 34.586678] device bridge_slave_0 entered promiscuous mode [ 34.603585] bridge0: port 2(bridge_slave_1) entered blocking state [ 34.609987] bridge0: port 2(bridge_slave_1) entered disabled state [ 34.617160] device bridge_slave_1 entered promiscuous mode [ 34.632341] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 34.648176] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 34.689504] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 34.707616] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 34.770148] IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready [ 34.778011] team0: Port device team_slave_0 added [ 34.792733] IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready [ 34.799836] team0: Port device team_slave_1 added [ 34.815803] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 34.833441] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 34.850277] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 34.867560] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 34.983207] bridge0: port 2(bridge_slave_1) entered blocking state [ 34.989645] bridge0: port 2(bridge_slave_1) entered forwarding state [ 34.996609] bridge0: port 1(bridge_slave_0) entered blocking state [ 35.002993] bridge0: port 1(bridge_slave_0) entered forwarding state [ 35.413152] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 35.419266] 8021q: adding VLAN 0 to HW filter on device bond0 [ 35.462190] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 35.504632] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 35.513390] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 35.551166] 8021q: adding VLAN 0 to HW filter on device team0 [ 35.806678] FAULT_INJECTION: forcing a failure. [ 35.806678] name failslab, interval 1, probability 0, space 0, times 1 [ 35.819286] CPU: 1 PID: 4774 Comm: syz-executor0 Not tainted 4.17.0+ #111 [ 35.826217] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 35.835549] Call Trace: [ 35.838128] dump_stack+0x1b9/0x294 [ 35.841747] ? dump_stack_print_info.cold.2+0x52/0x52 [ 35.846918] ? trace_hardirqs_off+0x10/0x10 [ 35.851237] should_fail.cold.4+0xa/0x1a [ 35.855299] ? fault_create_debugfs_attr+0x1f0/0x1f0 [ 35.860404] ? graph_lock+0x170/0x170 [ 35.864196] ? debug_check_no_locks_freed+0x310/0x310 [ 35.869371] ? process_echoes+0xb6/0x170 [ 35.873419] ? check_same_owner+0x320/0x320 [ 35.877724] ? print_usage_bug+0xc0/0xc0 [ 35.881779] ? __might_sleep+0x95/0x190 [ 35.885738] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 35.891260] __should_failslab+0x124/0x180 [ 35.895482] should_failslab+0x9/0x14 [ 35.899261] __kmalloc+0x63/0x760 [ 35.902707] ? mutex_trylock+0x2a0/0x2a0 [ 35.906764] ? __tty_buffer_request_room+0x2d2/0x7f0 [ 35.911854] __tty_buffer_request_room+0x2d2/0x7f0 [ 35.916770] ? flush_to_ldisc+0x560/0x560 [ 35.920923] ? lock_acquire+0x1dc/0x520 [ 35.924903] ? pty_write+0xf9/0x1f0 [ 35.928514] ? lock_release+0xa10/0xa10 [ 35.932470] ? kasan_check_read+0x11/0x20 [ 35.936601] ? do_raw_spin_unlock+0x9e/0x2e0 [ 35.940992] tty_insert_flip_string_fixed_flag+0x8d/0x1f0 [ 35.946525] ? do_raw_spin_lock+0xc1/0x200 [ 35.950746] pty_write+0x12c/0x1f0 [ 35.954279] tty_put_char+0x129/0x150 [ 35.958062] ? dev_match_devt+0x90/0x90 [ 35.962023] ? pty_write_room+0xc9/0xf0 [ 35.965985] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 35.971159] __process_echoes+0x4d9/0x8d0 [ 35.975288] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 35.980374] process_echoes+0xfc/0x170 [ 35.984242] n_tty_set_termios+0xb56/0xe80 [ 35.988488] ? n_tty_receive_signal_char+0x120/0x120 [ 35.993588] tty_set_termios+0x7a0/0xac0 [ 35.997638] ? tty_wait_until_sent+0x5b0/0x5b0 [ 36.002208] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.007738] set_termios+0x41e/0x7d0 [ 36.011445] ? tty_perform_flush+0x80/0x80 [ 36.015675] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.021195] tty_mode_ioctl+0x871/0xb50 [ 36.025153] ? set_termios+0x7d0/0x7d0 [ 36.029036] ? check_same_owner+0x320/0x320 [ 36.033347] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 36.038525] n_tty_ioctl_helper+0x54/0x3b0 [ 36.042749] n_tty_ioctl+0x54/0x320 [ 36.046360] ? ldsem_down_read+0x37/0x40 [ 36.050403] ? ldsem_down_read+0x37/0x40 [ 36.054454] tty_ioctl+0x5e1/0x1870 [ 36.058064] ? commit_echoes+0x1d0/0x1d0 [ 36.062106] ? tty_vhangup+0x30/0x30 [ 36.065800] ? zap_class+0x720/0x720 [ 36.069496] ? lock_release+0xa10/0xa10 [ 36.074161] ? proc_cwd_link+0x1d0/0x1d0 [ 36.078219] ? graph_lock+0x170/0x170 [ 36.082001] ? do_raw_spin_unlock+0x9e/0x2e0 [ 36.086397] ? find_held_lock+0x36/0x1c0 [ 36.090458] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.095979] ? find_held_lock+0x36/0x1c0 [ 36.100035] ? tty_vhangup+0x30/0x30 [ 36.103735] do_vfs_ioctl+0x1cf/0x16f0 [ 36.107604] ? lock_downgrade+0x8e0/0x8e0 [ 36.111736] ? ioctl_preallocate+0x2e0/0x2e0 [ 36.116127] ? check_same_owner+0x320/0x320 [ 36.120431] ? rcu_note_context_switch+0x710/0x710 [ 36.125373] ? __sb_end_write+0xac/0xe0 [ 36.129342] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.134864] ? ldsem_up_read+0x54/0x90 [ 36.138743] ? tty_ldisc_deref+0x35/0x40 [ 36.142788] ? tty_compat_ioctl+0x1ce/0x290 [ 36.147104] __ia32_compat_sys_ioctl+0x43e/0x640 [ 36.151864] do_fast_syscall_32+0x345/0xf9b [ 36.156168] ? do_int80_syscall_32+0x880/0x880 [ 36.160733] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 36.165475] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 36.171000] ? syscall_return_slowpath+0x30f/0x5c0 [ 36.175922] ? sysret32_from_system_call+0x5/0x46 [ 36.180750] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 36.185577] entry_SYSENTER_compat+0x70/0x7f [ 36.189964] RIP: 0023:0xf7ffbcb9 [ 36.193303] Code: 55 08 8b 88 64 cd ff ff 8b 98 68 cd ff ff 89 c8 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 1c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 [ 36.212451] RSP: 002b:00000000ff8664ec EFLAGS: 00000286 ORIG_RAX: 0000000000000036 [ 36.220142] RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000005406 [ 36.227395] RDX: 0000000020000040 RSI: 0000000000000000 RDI: 0000000000000000 [ 36.234654] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 36.241920] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 36.249171] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 36.256446] [ 36.256451] ====================================================== [ 36.256455] WARNING: possible circular locking dependency detected [ 36.256456] 4.17.0+ #111 Not tainted [ 36.256460] ------------------------------------------------------ [ 36.256462] syz-executor0/4774 is trying to acquire lock: [ 36.256464] (ptrval) (console_owner){-...}, at: console_unlock+0x583/0x1100 [ 36.256472] [ 36.256475] but task is already holding lock: [ 36.256476] (ptrval) (&(&port->lock)->rlock){-.-.}, at: pty_write+0xf9/0x1f0 [ 36.256484] [ 36.256487] which lock already depends on the new lock. [ 36.256488] [ 36.256489] [ 36.256492] the existing dependency chain (in reverse order) is: [ 36.256493] [ 36.256494] -> #2 (&(&port->lock)->rlock){-.-.}: [ 36.256502] _raw_spin_lock_irqsave+0x96/0xc0 [ 36.256504] tty_port_tty_get+0x20/0x80 [ 36.256507] tty_port_default_wakeup+0x15/0x40 [ 36.256509] tty_port_tty_wakeup+0x5d/0x70 [ 36.256511] uart_write_wakeup+0x44/0x60 [ 36.256514] serial8250_tx_chars+0x4be/0xb60 [ 36.256516] serial8250_handle_irq.part.25+0x1ee/0x280 [ 36.256519] serial8250_default_handle_irq+0xc8/0x150 [ 36.256521] serial8250_interrupt+0xfa/0x1d0 [ 36.256524] __handle_irq_event_percpu+0x1c0/0xad0 [ 36.256526] handle_irq_event_percpu+0x98/0x1c0 [ 36.256528] handle_irq_event+0xa7/0x135 [ 36.256530] handle_edge_irq+0x20f/0x870 [ 36.256533] handle_irq+0x18c/0x2e7 [ 36.256535] do_IRQ+0x78/0x190 [ 36.256537] ret_from_intr+0x0/0x1e [ 36.256539] native_safe_halt+0x6/0x10 [ 36.256541] default_idle+0xc2/0x440 [ 36.256543] arch_cpu_idle+0x10/0x20 [ 36.256546] default_idle_call+0x6d/0x90 [ 36.256548] do_idle+0x395/0x560 [ 36.256550] cpu_startup_entry+0x104/0x120 [ 36.256552] start_secondary+0x42b/0x5c0 [ 36.256555] secondary_startup_64+0xa5/0xb0 [ 36.256556] [ 36.256557] -> #1 (&port_lock_key){-.-.}: [ 36.256565] _raw_spin_lock_irqsave+0x96/0xc0 [ 36.256567] serial8250_console_write+0x8d5/0xb00 [ 36.256570] univ8250_console_write+0x5f/0x70 [ 36.256572] console_unlock+0xac2/0x1100 [ 36.256574] vprintk_emit+0x6ad/0xdd0 [ 36.256576] vprintk_default+0x28/0x30 [ 36.256578] vprintk_func+0x7a/0xe7 [ 36.256580] printk+0x9e/0xba [ 36.256582] register_console+0x7e7/0xc00 [ 36.256584] univ8250_console_init+0x3f/0x4b [ 36.256587] console_init+0x6d9/0xa38 [ 36.256589] start_kernel+0x608/0x92d [ 36.256591] x86_64_start_reservations+0x29/0x2b [ 36.256593] x86_64_start_kernel+0x76/0x79 [ 36.256596] secondary_startup_64+0xa5/0xb0 [ 36.256597] [ 36.256598] -> #0 (console_owner){-...}: [ 36.256605] lock_acquire+0x1dc/0x520 [ 36.256608] console_unlock+0x5ef/0x1100 [ 36.256610] vprintk_emit+0x6ad/0xdd0 [ 36.256612] vprintk_default+0x28/0x30 [ 36.256614] vprintk_func+0x7a/0xe7 [ 36.256616] printk+0x9e/0xba [ 36.256618] should_fail+0x97a/0xbcd [ 36.256620] __should_failslab+0x124/0x180 [ 36.256622] should_failslab+0x9/0x14 [ 36.256624] __kmalloc+0x63/0x760 [ 36.256627] __tty_buffer_request_room+0x2d2/0x7f0 [ 36.256629] tty_insert_flip_string_fixed_flag+0x8d/0x1f0 [ 36.256631] pty_write+0x12c/0x1f0 [ 36.256634] tty_put_char+0x129/0x150 [ 36.256636] __process_echoes+0x4d9/0x8d0 [ 36.256638] process_echoes+0xfc/0x170 [ 36.256640] n_tty_set_termios+0xb56/0xe80 [ 36.256642] tty_set_termios+0x7a0/0xac0 [ 36.256644] set_termios+0x41e/0x7d0 [ 36.256647] tty_mode_ioctl+0x871/0xb50 [ 36.256649] n_tty_ioctl_helper+0x54/0x3b0 [ 36.256651] n_tty_ioctl+0x54/0x320 [ 36.256653] tty_ioctl+0x5e1/0x1870 [ 36.256655] do_vfs_ioctl+0x1cf/0x16f0 [ 36.256658] __ia32_compat_sys_ioctl+0x43e/0x640 [ 36.256660] do_fast_syscall_32+0x345/0xf9b [ 36.256662] entry_SYSENTER_compat+0x70/0x7f [ 36.256664] [ 36.256666] other info that might help us debug this: [ 36.256667] [ 36.256669] Chain exists of: [ 36.256670] console_owner --> &port_lock_key --> &(&port->lock)->rlock [ 36.256680] [ 36.256682] Possible unsafe locking scenario: [ 36.256683] [ 36.256685] CPU0 CPU1 [ 36.256687] ---- ---- [ 36.256689] lock(&(&port->lock)->rlock); [ 36.256694] lock(&port_lock_key); [ 36.256699] lock(&(&port->lock)->rlock); [ 36.256703] lock(console_owner); [ 36.256707] [ 36.256709] *** DEADLOCK *** [ 36.256710] [ 36.256713] 6 locks held by syz-executor0/4774: [ 36.256714] #0: (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 36.256723] #1: (ptrval) (&o_tty->termios_rwsem/1){++++}, at: tty_set_termios+0xfd/0xac0 [ 36.256733] #2: (ptrval) (&tty->ldisc_sem){++++}, at: tty_ldisc_ref+0x22/0x90 [ 36.256742] #3: (ptrval) (&ldata->output_lock){+.+.}, at: process_echoes+0xb6/0x170 [ 36.256751] #4: (ptrval) (&(&port->lock)->rlock){-.-.}, at: pty_write+0xf9/0x1f0 [ 36.256760] #5: (ptrval) (console_lock){+.+.}, at: vprintk_emit+0x694/0xdd0 [ 36.256769] [ 36.256770] stack backtrace: [ 36.256774] CPU: 1 PID: 4774 Comm: syz-executor0 Not tainted 4.17.0+ #111 [ 36.256778] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.256780] Call Trace: [ 36.256782] dump_stack+0x1b9/0x294 [ 36.256784] ? dump_stack_print_info.cold.2+0x52/0x52 [ 36.256786] ? vprintk_func+0xd0/0xe7 [ 36.256789] print_circular_bug.isra.36.cold.56+0x1bd/0x27d [ 36.256791] ? save_trace+0xe0/0x290 [ 36.256793] __lock_acquire+0x343e/0x5140 [ 36.256796] ? debug_check_no_locks_freed+0x310/0x310 [ 36.256798] ? kasan_check_read+0x11/0x20 [ 36.256800] ? put_dec_trunc8+0x273/0x300 [ 36.256802] ? number+0x967/0xc90 [ 36.256804] ? perf_trace_lock+0xd6/0x900 [ 36.256807] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 36.256809] ? zap_class+0x720/0x720 [ 36.256811] ? graph_lock+0x170/0x170 [ 36.256814] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.256816] ? pointer+0xa10/0xa10 [ 36.256818] lock_acquire+0x1dc/0x520 [ 36.256820] ? console_unlock+0x583/0x1100 [ 36.256822] ? lock_release+0xa10/0xa10 [ 36.256824] ? kasan_check_read+0x11/0x20 [ 36.256826] ? do_raw_spin_unlock+0x9e/0x2e0 [ 36.256829] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 36.256831] ? kasan_check_write+0x14/0x20 [ 36.256833] ? do_raw_spin_lock+0xc1/0x200 [ 36.256835] console_unlock+0x5ef/0x1100 [ 36.256837] ? console_unlock+0x583/0x1100 [ 36.256839] ? wake_up_klogd+0x100/0x100 [ 36.256842] ? kasan_check_write+0x14/0x20 [ 36.256844] ? do_raw_spin_lock+0xc1/0x200 [ 36.256846] ? trace_hardirqs_off+0xd/0x10 [ 36.256848] ? _raw_spin_unlock_irqrestore+0x63/0xc0 [ 36.256851] ? vprintk_emit+0x694/0xdd0 [ 36.256853] ? __down_trylock_console_sem+0x155/0x200 [ 36.256855] vprintk_emit+0x6ad/0xdd0 [ 36.256857] ? console_unlock+0x1100/0x1100 [ 36.256859] ? check_usage+0x19f/0x770 [ 36.256862] ? rcu_report_qs_rnp+0x790/0x790 [ 36.256864] ? __bfs+0x388/0x790 [ 36.256866] vprintk_default+0x28/0x30 [ 36.256868] vprintk_func+0x7a/0xe7 [ 36.256869] printk+0x9e/0xba [ 36.256872] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 36.256874] ? trace_hardirqs_off+0x10/0x10 [ 36.256876] should_fail+0x97a/0xbcd [ 36.256879] ? fault_create_debugfs_attr+0x1f0/0x1f0 [ 36.256881] ? graph_lock+0x170/0x170 [ 36.256883] ? debug_check_no_locks_freed+0x310/0x310 [ 36.256885] ? process_echoes+0xb6/0x170 [ 36.256888] ? check_same_owner+0x320/0x320 [ 36.256890] ? print_usage_bug+0xc0/0xc0 [ 36.256892] ? __might_sleep+0x95/0x190 [ 36.256894] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.256897] __should_failslab+0x124/0x180 [ 36.256899] should_failslab+0x9/0x14 [ 36.256901] __kmalloc+0x63/0x760 [ 36.256903] ? mutex_trylock+0x2a0/0x2a0 [ 36.256905] ? __tty_buffer_request_room+0x2d2/0x7f0 [ 36.256908] __tty_buffer_request_room+0x2d2/0x7f0 [ 36.256910] ? flush_to_ldisc+0x560/0x560 [ 36.256912] ? lock_acquire+0x1dc/0x520 [ 36.256914] ? pty_write+0xf9/0x1f0 [ 36.256916] ? lock_release+0xa10/0xa10 [ 36.256918] ? kasan_check_read+0x11/0x20 [ 36.256920] ? do_raw_spin_unlock+0x9e/0x2e0 [ 36.256923] tty_insert_flip_string_fixed_flag+0x8d/0x1f0 [ 36.256925] ? do_raw_spin_lock+0xc1/0x200 [ 36.256927] pty_write+0x12c/0x1f0 [ 36.256929] tty_put_char+0x129/0x150 [ 36.256931] ? dev_match_devt+0x90/0x90 [ 36.256933] ? pty_write_room+0xc9/0xf0 [ 36.256936] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 36.256938] __process_echoes+0x4d9/0x8d0 [ 36.256940] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 36.256942] process_echoes+0xfc/0x170 [ 36.256945] n_tty_set_termios+0xb56/0xe80 [ 36.256947] ? n_tty_receive_signal_char+0x120/0x120 [ 36.256949] tty_set_termios+0x7a0/0xac0 [ 36.256952] ? tty_wait_until_sent+0x5b0/0x5b0 [ 36.256954] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.256957] set_termios+0x41e/0x7d0 [ 36.256959] ? tty_perform_flush+0x80/0x80 [ 36.256962] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.256964] tty_mode_ioctl+0x871/0xb50 [ 36.256966] ? set_termios+0x7d0/0x7d0 [ 36.256968] ? check_same_owner+0x320/0x320 [ 36.256971] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 36.256973] n_tty_ioctl_helper+0x54/0x3b0 [ 36.256975] n_tty_ioctl+0x54/0x320 [ 36.256977] ? ldsem_down_read+0x37/0x40 [ 36.256980] ? ldsem_down_read+0x37/0x40 [ 36.256981] tty_ioctl+0x5e1/0x1870 [ 36.256984] ? commit_echoes+0x1d0/0x1d0 [ 36.256986] ? tty_vhangup+0x30/0x30 [ 36.256988] ? zap_class+0x720/0x720 [ 36.256990] ? lock_release+0xa10/0xa10 [ 36.256992] ? proc_cwd_link+0x1d0/0x1d0 [ 36.256994] ? graph_lock+0x170/0x170 [ 36.256996] ? do_raw_spin_unlock+0x9e/0x2e0 [ 36.256998] ? find_held_lock+0x36/0x1c0 [ 36.257001] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.257005] ? find_held_lock+0x36/0x1c0 [ 36.257008] ? tty_vhangup+0x30/0x30 [ 36.257012] do_vfs_ioctl+0x1cf/0x16f0 [ 36.257016] ? lock_downgrade+0x8e0/0x8e0 [ 36.257019] ? ioctl_preallocate+0x2e0/0x2e0 [ 36.257023] ? check_same_owner+0x320/0x320 [ 36.257028] ? rcu_note_context_switch+0x710/0x710 [ 36.257030] ? __sb_end_write+0xac/0xe0 [ 36.257033] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.257035] ? ldsem_up_read+0x54/0x90 [ 36.257037] ? tty_ldisc_deref+0x35/0x40 [ 36.257039] ? tty_compat_ioctl+0x1ce/0x290 [ 36.257042] __ia32_compat_sys_ioctl+0x43e/0x640 [