[ OK ] Started OpenBSD Secure Shell server. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.1' (ECDSA) to the list of known hosts. syzkaller login: [ 616.332787][ T1166] INFO: task syz-executor488:6806 blocked for more than 143 seconds. [ 616.341009][ T1166] Not tainted 5.8.0-syzkaller #0 [ 616.348523][ T1166] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 616.357694][ T1166] syz-executor488 D28368 6806 6800 0x80004002 [ 616.364469][ T1166] Call Trace: [ 616.367972][ T1166] __schedule+0x979/0xce0 [ 616.372280][ T1166] ? schedule+0x188/0x220 [ 616.377758][ T1166] ? io_uring_flush+0x8fd/0xb50 [ 616.383148][ T1166] ? init_wait_entry+0xd0/0xd0 [ 616.387898][ T1166] ? io_uring_mmap+0x330/0x330 [ 616.393473][ T1166] ? filp_close+0xad/0x150 [ 616.398070][ T1166] ? put_files_struct+0x1d1/0x360 [ 616.403928][ T1166] ? do_exit+0x5a5/0x1f20 [ 616.408280][ T1166] ? __se_sys_io_uring_enter+0x10cc/0x1300 [ 616.414843][ T1166] ? do_group_exit+0x161/0x2d0 [ 616.419674][ T1166] ? syscall_enter_from_user_mode+0x24/0x190 [ 616.426443][ T1166] ? __do_sys_exit_group+0x13/0x20 [ 616.431565][ T1166] ? __se_sys_exit_group+0x10/0x10 [ 616.437787][ T1166] ? __x64_sys_exit_group+0x37/0x40 [ 616.443460][ T1166] ? do_syscall_64+0x31/0x70 [ 616.448121][ T1166] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 616.454939][ T1166] [ 616.454939][ T1166] Showing all locks held in the system: [ 616.463260][ T1166] 1 lock held by khungtaskd/1166: [ 616.468272][ T1166] #0: ffffffff894fe1d0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 [ 616.478920][ T1166] 1 lock held by in:imklog/6486: [ 616.484304][ T1166] #0: ffff88809946b870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x253/0x2f0 [ 616.493963][ T1166] [ 616.496283][ T1166] ============================================= [ 616.496283][ T1166] [ 616.507466][ T1166] NMI backtrace for cpu 1 [ 616.511860][ T1166] CPU: 1 PID: 1166 Comm: khungtaskd Not tainted 5.8.0-syzkaller #0 [ 616.519914][ T1166] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 616.530376][ T1166] Call Trace: [ 616.533741][ T1166] dump_stack+0x1f0/0x31e [ 616.538149][ T1166] nmi_cpu_backtrace+0x9f/0x180 [ 616.543044][ T1166] ? arch_trigger_cpumask_backtrace+0x10/0x10 [ 616.549098][ T1166] nmi_trigger_cpumask_backtrace+0x16a/0x280 [ 616.555109][ T1166] watchdog+0xd65/0xdb0 [ 616.559326][ T1166] kthread+0x37e/0x3a0 [ 616.563370][ T1166] ? hungtask_pm_notify+0x50/0x50 [ 616.568364][ T1166] ? kthread_blkcg+0xd0/0xd0 [ 616.573023][ T1166] ret_from_fork+0x1f/0x30 [ 616.577776][ T1166] Sending NMI from CPU 1 to CPUs 0: [ 616.583763][ C0] NMI backtrace for cpu 0 [ 616.583772][ C0] CPU: 0 PID: 3897 Comm: systemd-journal Not tainted 5.8.0-syzkaller #0 [ 616.583776][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 616.583781][ C0] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0xa0 [ 616.583793][ C0] Code: c1 e0 03 48 83 c8 18 48 89 34 01 4c 89 44 f9 18 49 ff c2 4c 89 11 c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 4c 8b 04 24 <65> 48 8b 14 25 00 fe 01 00 65 8b 05 a8 0b 8d 7e a9 00 01 ff 00 74 [ 616.583798][ C0] RSP: 0018:ffffc900054e7ae8 EFLAGS: 00000246 [ 616.583803][ C0] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff8880a928a200 [ 616.583806][ C0] RDX: ffff8880a928a200 RSI: 0000000000000000 RDI: 0000000000000000 [ 616.583809][ C0] RBP: 0000000000000001 R08: ffffffff83618087 R09: ffffc900054e7bc8 [ 616.583812][ C0] R10: fffff52000a9cf7d R11: 0000000000000000 R12: ffffffff890a72d3 [ 616.583815][ C0] R13: 0000000000000000 R14: ffffc900054e7ba0 R15: ffffffff890a72d3 [ 616.583818][ C0] FS: 00007f91708398c0(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 [ 616.583821][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 616.583827][ C0] CR2: 00007f916dbd6000 CR3: 0000000092812000 CR4: 00000000001506f0 [ 616.583832][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 616.583838][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 616.583842][ C0] Call Trace: [ 616.583844][ C0] smack_log+0x87/0x490 [ 616.583849][ C0] smk_tskacc+0x2e5/0x390 [ 616.583853][ C0] smack_inode_permission+0x241/0x2b0 [ 616.583858][ C0] security_inode_permission+0x92/0x110 [ 616.583863][ C0] link_path_walk+0x20e/0xba0 [ 616.583865][ C0] path_lookupat+0xab/0x960 [ 616.583867][ C0] filename_lookup+0x1ab/0x5d0 [ 616.583868][ C0] ? getname_flags+0x20d/0x610 [ 616.583873][ C0] do_faccessat+0x3a0/0x870 [ 616.583878][ C0] do_syscall_64+0x31/0x70 [ 616.583883][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 616.583888][ C0] RIP: 0033:0x7f916faf59c7 [ 616.583901][ C0] Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 [ 616.583904][ C0] RSP: 002b:00007fffc39a1ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 [ 616.583914][ C0] RAX: ffffffffffffffda RBX: 00007fffc39a4c00 RCX: 00007f916faf59c7 [ 616.583923][ C0] RDX: 00007f9170566a00 RSI: 0000000000000000 RDI: 00005610c43429a3 [ 616.583928][ C0] RBP: 00007fffc39a1d20 R08: 0000000000000000 R09: 0000000000000000 [ 616.583934][ C0] R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 [ 616.583939][ C0] R13: 0000000000000000 R14: 00007fffc39a4c00 R15: 00007fffc39a2210 [ 616.584214][ T1166] Kernel panic - not syncing: hung_task: blocked tasks [ 616.856465][ T1166] CPU: 1 PID: 1166 Comm: khungtaskd Not tainted 5.8.0-syzkaller #0 [ 616.864325][ T1166] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 616.874368][ T1166] Call Trace: [ 616.877808][ T1166] dump_stack+0x1f0/0x31e [ 616.882167][ T1166] panic+0x264/0x7a0 [ 616.886036][ T1166] ? nmi_trigger_cpumask_backtrace+0x206/0x280 [ 616.892160][ T1166] watchdog+0xda5/0xdb0 [ 616.896317][ T1166] kthread+0x37e/0x3a0 [ 616.900382][ T1166] ? hungtask_pm_notify+0x50/0x50 [ 616.905376][ T1166] ? kthread_blkcg+0xd0/0xd0 [ 616.909937][ T1166] ret_from_fork+0x1f/0x30 [ 616.916077][ T1166] Kernel Offset: disabled [ 616.920399][ T1166] Rebooting in 86400 seconds..