Warning: Permanently added '10.128.0.251' (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 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program 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: [ 1001.407148] INFO: task syz-executor046:8416 blocked for more than 140 seconds. [ 1001.407156] Not tainted 4.14.209-syzkaller #0 [ 1001.407160] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1001.407165] syz-executor046 D28912 8416 7986 0x00000004 [ 1001.407279] Call Trace: [ 1001.407386] __schedule+0x88b/0x1de0 [ 1001.407442] ? kernel_poison_pages+0x1b/0x250 [ 1001.407478] ? io_schedule_timeout+0x140/0x140 [ 1001.407519] ? __lock_acquire+0x5fc/0x3f20 [ 1001.407531] ? __down+0x124/0x260 [ 1001.407538] schedule+0x8d/0x1b0 [ 1001.407547] schedule_timeout+0x80a/0xe90 [ 1001.407554] ? __lock_acquire+0x5fc/0x3f20 [ 1001.407565] ? usleep_range+0x130/0x130 [ 1001.407572] ? trace_hardirqs_on+0x10/0x10 [ 1001.407579] ? __down+0x165/0x260 [ 1001.407591] ? lock_downgrade+0x740/0x740 [ 1001.407625] ? _raw_spin_unlock_irq+0x24/0x80 [ 1001.407636] ? __down+0x124/0x260 [ 1001.407642] __down+0x16d/0x260 [ 1001.407653] ? ww_mutex_lock+0x180/0x180 [ 1001.407692] down+0x57/0x80 [ 1001.407730] console_lock+0x24/0x70 [ 1001.407785] do_fb_ioctl+0x2e7/0xa70 [ 1001.407835] ? wp_page_copy+0xc31/0x25c0 [ 1001.407844] ? register_framebuffer+0x8e0/0x8e0 [ 1001.407854] ? lock_downgrade+0x740/0x740 [ 1001.407911] ? __lru_cache_add+0x178/0x250 [ 1001.407939] ? page_remove_rmap.part.0+0xe/0x190 [ 1001.407949] ? do_raw_spin_unlock+0x164/0x220 [ 1001.407958] ? _raw_spin_unlock+0x29/0x40 [ 1001.407966] ? wp_page_copy+0xf91/0x25c0 [ 1001.407982] ? tlb_flush_mmu_free+0x1a0/0x1a0 [ 1001.407990] ? __lock_acquire+0x5fc/0x3f20 [ 1001.408012] ? __handle_mm_fault+0x80f/0x4620 [ 1001.408024] fb_ioctl+0xdd/0x130 [ 1001.408031] ? do_fb_ioctl+0xa70/0xa70 [ 1001.408076] do_vfs_ioctl+0x75a/0xff0 [ 1001.408088] ? ioctl_preallocate+0x1a0/0x1a0 [ 1001.408101] ? lock_downgrade+0x740/0x740 [ 1001.408139] ? security_file_ioctl+0x83/0xb0 [ 1001.408149] SyS_ioctl+0x7f/0xb0 [ 1001.408157] ? do_vfs_ioctl+0xff0/0xff0 [ 1001.408192] do_syscall_64+0x1d5/0x640 [ 1001.408206] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1001.408214] RIP: 0033:0x445189 [ 1001.408219] RSP: 002b:00007ffcec01b8b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1001.408229] RAX: ffffffffffffffda RBX: 0000000020000080 RCX: 0000000000445189 [ 1001.408234] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 [ 1001.408239] RBP: 00000000000bed59 R08: 00000000004002e0 R09: 00000000004002e0 [ 1001.408244] R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000402350 [ 1001.408249] R13: 00000000004023e0 R14: 0000000000000000 R15: 0000000000000000 [ 1001.408266] [ 1001.408266] Showing all locks held in the system: [ 1001.408275] 1 lock held by khungtaskd/1532: [ 1001.408279] #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a [ 1001.408312] 1 lock held by in:imklog/7651: [ 1001.408315] #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x1fb/0x2b0 [ 1001.408337] 2 locks held by agetty/7701: [ 1001.408340] #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 [ 1001.408386] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e3/0x1680 [ 1001.408427] [ 1001.408431] ============================================= [ 1001.408431] [ 1001.408435] NMI backtrace for cpu 1 [ 1001.408444] CPU: 1 PID: 1532 Comm: khungtaskd Not tainted 4.14.209-syzkaller #0 [ 1001.408455] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1001.408458] Call Trace: [ 1001.408488] dump_stack+0x1b2/0x283 [ 1001.408500] nmi_cpu_backtrace.cold+0x57/0x93 [ 1001.408531] ? irq_force_complete_move.cold+0x89/0x89 [ 1001.408540] nmi_trigger_cpumask_backtrace+0x13a/0x17f [ 1001.408571] watchdog+0x5b9/0xb40 [ 1001.408582] ? hungtask_pm_notify+0x50/0x50 [ 1001.408637] kthread+0x30d/0x420 [ 1001.408647] ? kthread_create_on_node+0xd0/0xd0 [ 1001.408657] ret_from_fork+0x24/0x30 [ 1001.408674] Sending NMI from CPU 1 to CPUs 0: [ 1001.409240] NMI backtrace for cpu 0 [ 1001.409245] CPU: 0 PID: 22 Comm: kworker/u4:1 Not tainted 4.14.209-syzkaller #0 [ 1001.409249] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1001.409252] Workqueue: events_unbound flush_to_ldisc [ 1001.409257] task: ffff8880b55f85c0 task.stack: ffff8880b5600000 [ 1001.409260] RIP: 0010:__sanitizer_cov_trace_pc+0x23/0x50 [ 1001.409262] RSP: 0018:ffff8880b56075f8 EFLAGS: 00000246 [ 1001.409268] RAX: ffff8880b55f85c0 RBX: ffff8880000a0035 RCX: 0000000000000000 [ 1001.409271] RDX: 0000000000000000 RSI: ffff8880b5607690 RDI: ffff8880b56076a0 [ 1001.409275] RBP: 0000000000000050 R08: 0000000000000010 R09: 0000000000000280 [ 1001.409278] R10: ffffffff8c8ad014 R11: 0000000000000000 R12: 00000000aa32f28e [ 1001.409282] R13: ffffffffffffffb0 R14: ffff8880000a0050 R15: 0000000000000000 [ 1001.409286] FS: 0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 [ 1001.409289] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1001.409292] CR2: 00000000006cf090 CR3: 00000000b3a82000 CR4: 00000000001406f0 [ 1001.409296] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1001.409299] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1001.409301] Call Trace: [ 1001.409304] vga16fb_fillrect+0x910/0x1820 [ 1001.409306] bit_clear+0x32a/0x450 [ 1001.409309] ? bit_bmove+0x1e0/0x1e0 [ 1001.409311] fbcon_clear+0x558/0x650 [ 1001.409313] ? bit_bmove+0x1e0/0x1e0 [ 1001.409316] fbcon_scroll+0x3c1/0x31e0 [ 1001.409318] con_scroll+0x2c5/0x360 [ 1001.409321] ? lock_acquire+0x170/0x3f0 [ 1001.409323] lf+0x226/0x270 [ 1001.409325] ? con_scroll+0x360/0x360 [ 1001.409328] ? __atomic_notifier_call_chain+0xbd/0x140 [ 1001.409330] do_con_write+0xf9b/0x19b0 [ 1001.409333] ? do_con_trol+0x51e0/0x51e0 [ 1001.409335] ? do_con_write+0x19b0/0x19b0 [ 1001.409337] con_put_char+0x78/0xa0 [ 1001.409340] ? do_con_write+0x19b0/0x19b0 [ 1001.409342] ? do_con_write+0x19b0/0x19b0 [ 1001.409345] ? con_put_char+0x80/0xa0 [ 1001.409347] tty_put_char+0xa3/0x120 [ 1001.409349] ? dev_match_devt+0x80/0x80 [ 1001.409352] ? tty_put_char+0xab/0x120 [ 1001.409354] do_output_char+0x126/0x750 [ 1001.409357] __process_echoes+0x313/0x8c0 [ 1001.409359] n_tty_receive_buf_common+0x9a3/0x25a0 [ 1001.409362] ? n_tty_receive_buf_common+0x25a0/0x25a0 [ 1001.409365] tty_ldisc_receive_buf+0x9e/0x170 [ 1001.409368] tty_port_default_receive_buf+0x6e/0xa0 [ 1001.409370] flush_to_ldisc+0x1dd/0x3f0 [ 1001.409373] process_one_work+0x793/0x14a0 [ 1001.409375] ? work_busy+0x320/0x320 [ 1001.409377] ? worker_thread+0x158/0xff0 [ 1001.409380] ? _raw_spin_unlock_irq+0x24/0x80 [ 1001.409382] worker_thread+0x5cc/0xff0 [ 1001.409385] ? rescuer_thread+0xc80/0xc80 [ 1001.409387] kthread+0x30d/0x420 [ 1001.409390] ? kthread_create_on_node+0xd0/0xd0 [ 1001.409392] ret_from_fork+0x24/0x30 [ 1001.409394] Code: 00 00 e9 c6 ed ff ff 90 65 48 8b 04 25 80 df 01 00 48 85 c0 74 1a 65 8b 15 bb 9f aa 7e 81 e2 00 01 1f 00 75 0b 8b 90 58 13 00 00 <83> fa 01 74 01 c3 48 8b 34 24 48 8b 88 60 13 00 00 8b 80 5c 13 [ 1001.409689] Kernel panic - not syncing: hung_task: blocked tasks [ 1001.409697] CPU: 1 PID: 1532 Comm: khungtaskd Not tainted 4.14.209-syzkaller #0 [ 1001.409701] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1001.409704] Call Trace: [ 1001.409713] dump_stack+0x1b2/0x283 [ 1001.409765] panic+0x1f9/0x42d [ 1001.409775] ? add_taint.cold+0x16/0x16 [ 1001.409786] ? printk_safe_flush+0xa9/0x110 [ 1001.409800] watchdog+0x5ca/0xb40 [ 1001.409810] ? hungtask_pm_notify+0x50/0x50 [ 1001.409820] kthread+0x30d/0x420 [ 1001.409828] ? kthread_create_on_node+0xd0/0xd0 [ 1001.409837] ret_from_fork+0x24/0x30 [ 1001.410340] Kernel Offset: disabled