[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.181' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 454.011342][ T28] audit: type=1400 audit(1597233180.078:8): avc: denied { execmem } for pid=6862 comm="syz-executor709" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 597.912276][ T1169] INFO: task syz-executor709:6862 blocked for more than 143 seconds. [ 597.922089][ T1169] Not tainted 5.8.0-syzkaller #0 [ 597.927937][ T1169] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 597.939258][ T1169] syz-executor709 D27648 6862 6856 0x80000002 [ 597.946421][ T1169] Call Trace: [ 597.949815][ T1169] __schedule+0x8e5/0x21e0 [ 597.954643][ T1169] ? io_schedule_timeout+0x140/0x140 [ 597.960147][ T1169] ? io_wq_cancel_all+0x5a0/0x5a0 [ 597.966784][ T1169] ? _raw_spin_unlock_irq+0x1f/0x80 [ 597.972525][ T1169] schedule+0xd0/0x2a0 [ 597.976632][ T1169] io_uring_flush+0x740/0xa90 [ 597.981306][ T1169] ? io_req_task_cancel+0x20/0x20 [ 597.990034][ T1169] ? add_wait_queue_exclusive+0x180/0x180 [ 597.996660][ T1169] ? find_held_lock+0x2d/0x110 [ 598.001679][ T1169] ? lock_is_held_type+0xbb/0xf0 [ 598.007052][ T1169] ? io_req_task_cancel+0x20/0x20 [ 598.012254][ T1169] filp_close+0xb4/0x170 [ 598.016690][ T1169] put_files_struct+0x1cc/0x350 [ 598.021751][ T1169] exit_files+0x7e/0xa0 [ 598.026159][ T1169] do_exit+0xb43/0x29f0 [ 598.030742][ T1169] ? mm_update_next_owner+0x7a0/0x7a0 [ 598.036306][ T1169] ? io_submit_sqes+0x2380/0x2380 [ 598.041925][ T1169] ? __sys_socket+0x16d/0x200 [ 598.046707][ T1169] ? lock_is_held_type+0xbb/0xf0 [ 598.052200][ T1169] do_group_exit+0x125/0x310 [ 598.057358][ T1169] __x64_sys_exit_group+0x3a/0x50 [ 598.062772][ T1169] do_syscall_64+0x2d/0x70 [ 598.067210][ T1169] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 598.073854][ T1169] RIP: 0033:0x43f608 [ 598.077757][ T1169] Code: Bad RIP value. [ 598.082887][ T1169] RSP: 002b:00007ffff0b28e28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 598.093317][ T1169] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f608 [ 598.102295][ T1169] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 598.111255][ T1169] RBP: 00000000004bee08 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 598.119953][ T1169] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 598.129053][ T1169] R13: 00000000006d11a0 R14: 0000000000000000 R15: 0000000000000000 [ 598.137663][ T1169] [ 598.137663][ T1169] Showing all locks held in the system: [ 598.145756][ T1169] 1 lock held by khungtaskd/1169: [ 598.151534][ T1169] #0: ffffffff89bd62c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 [ 598.161728][ T1169] 1 lock held by in:imklog/6537: [ 598.167146][ T1169] #0: ffff88809ed316b0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 [ 598.177700][ T1169] [ 598.181568][ T1169] ============================================= [ 598.181568][ T1169] [ 598.190655][ T1169] NMI backtrace for cpu 0 [ 598.195258][ T1169] CPU: 0 PID: 1169 Comm: khungtaskd Not tainted 5.8.0-syzkaller #0 [ 598.204162][ T1169] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 598.215597][ T1169] Call Trace: [ 598.219382][ T1169] dump_stack+0x18f/0x20d [ 598.224213][ T1169] nmi_cpu_backtrace.cold+0x70/0xb1 [ 598.230053][ T1169] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 598.236697][ T1169] nmi_trigger_cpumask_backtrace+0x1b3/0x223 [ 598.243538][ T1169] watchdog+0xd7d/0x1000 [ 598.248338][ T1169] ? reset_hung_task_detector+0x30/0x30 [ 598.254124][ T1169] kthread+0x3b5/0x4a0 [ 598.258681][ T1169] ? __kthread_bind_mask+0xc0/0xc0 [ 598.264575][ T1169] ? __kthread_bind_mask+0xc0/0xc0 [ 598.275505][ T1169] ret_from_fork+0x1f/0x30 [ 598.280520][ T1169] Sending NMI from CPU 0 to CPUs 1: [ 598.286385][ C1] NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 [ 598.287982][ T1169] Kernel panic - not syncing: hung_task: blocked tasks [ 598.302620][ T1169] CPU: 0 PID: 1169 Comm: khungtaskd Not tainted 5.8.0-syzkaller #0 [ 598.311465][ T1169] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 598.322696][ T1169] Call Trace: [ 598.326303][ T1169] dump_stack+0x18f/0x20d [ 598.330625][ T1169] panic+0x2e3/0x75c [ 598.334738][ T1169] ? __warn_printk+0xf3/0xf3 [ 598.340521][ T1169] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 598.346701][ T1169] ? preempt_schedule_thunk+0x16/0x18 [ 598.352367][ T1169] ? watchdog.cold+0x5/0x16b [ 598.357207][ T1169] ? watchdog+0xa82/0x1000 [ 598.361869][ T1169] watchdog.cold+0x16/0x16b [ 598.366986][ T1169] ? reset_hung_task_detector+0x30/0x30 [ 598.372928][ T1169] kthread+0x3b5/0x4a0 [ 598.377430][ T1169] ? __kthread_bind_mask+0xc0/0xc0 [ 598.383171][ T1169] ? __kthread_bind_mask+0xc0/0xc0 [ 598.391910][ T1169] ret_from_fork+0x1f/0x30 [ 598.399975][ T1169] Kernel Offset: disabled [ 598.405372][ T1169] Rebooting in 86400 seconds..