[ OK ] Reached target Login Prompts. [ 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 '10.128.0.218' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 1053.194777] audit: type=1400 audit(1601849290.252:8): avc: denied { execmem } for pid=6375 comm="syz-executor714" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 1288.031190] INFO: task syz-executor714:6382 blocked for more than 140 seconds. [ 1288.031197] Not tainted 4.14.198-syzkaller #0 [ 1288.031200] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1288.031204] syz-executor714 D28912 6382 6381 0x00000004 [ 1288.031223] Call Trace: [ 1288.031276] __schedule+0x88b/0x1de0 [ 1288.031322] ? kernel_poison_pages+0x1b/0x250 [ 1288.031335] ? io_schedule_timeout+0x140/0x140 [ 1288.031385] ? __lock_acquire+0x5fc/0x3f20 [ 1288.031415] ? __down+0x124/0x260 [ 1288.031422] schedule+0x8d/0x1b0 [ 1288.031431] schedule_timeout+0x80a/0xe90 [ 1288.031439] ? __lock_acquire+0x5fc/0x3f20 [ 1288.031449] ? usleep_range+0x130/0x130 [ 1288.031456] ? trace_hardirqs_on+0x10/0x10 [ 1288.031464] ? __down+0x165/0x260 [ 1288.031476] ? lock_downgrade+0x740/0x740 [ 1288.031485] ? _raw_spin_unlock_irq+0x24/0x80 [ 1288.031496] ? __down+0x124/0x260 [ 1288.031503] __down+0x16d/0x260 [ 1288.031513] ? ww_mutex_lock+0x180/0x180 [ 1288.031527] down+0x57/0x80 [ 1288.031553] console_lock+0x24/0x70 [ 1288.031600] do_fb_ioctl+0x2e7/0xa70 [ 1288.031610] ? register_framebuffer+0x8e0/0x8e0 [ 1288.031643] ? avc_has_extended_perms+0x6e4/0xbf0 [ 1288.031666] ? _raw_spin_unlock+0x29/0x40 [ 1288.031673] ? avc_ss_reset+0x100/0x100 [ 1288.031718] ? tlb_flush_mmu_free+0x1a0/0x1a0 [ 1288.031726] ? __lock_acquire+0x5fc/0x3f20 [ 1288.031751] fb_ioctl+0xdd/0x130 [ 1288.031758] ? do_fb_ioctl+0xa70/0xa70 [ 1288.031782] do_vfs_ioctl+0x75a/0xff0 [ 1288.031808] ? selinux_inode_setxattr+0x730/0x730 [ 1288.031817] ? ioctl_preallocate+0x1a0/0x1a0 [ 1288.031828] ? lock_downgrade+0x740/0x740 [ 1288.031856] ? security_file_ioctl+0x83/0xb0 [ 1288.031886] SyS_ioctl+0x7f/0xb0 [ 1288.031894] ? do_vfs_ioctl+0xff0/0xff0 [ 1288.031904] do_syscall_64+0x1d5/0x640 [ 1288.031916] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1288.031923] RIP: 0033:0x4414e9 [ 1288.031927] RSP: 002b:00007ffe8b7eab28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1288.031936] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004414e9 [ 1288.031941] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 [ 1288.031946] RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8 [ 1288.031950] R10: 0000000000000004 R11: 0000000000000246 R12: 00000000004021e0 [ 1288.031955] R13: 0000000000402270 R14: 0000000000000000 R15: 0000000000000000 [ 1288.031971] INFO: task syz-executor714:6384 blocked for more than 140 seconds. [ 1288.031975] Not tainted 4.14.198-syzkaller #0 [ 1288.031978] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1288.031982] syz-executor714 D28912 6384 6377 0x00000004 [ 1288.031997] Call Trace: [ 1288.032008] __schedule+0x88b/0x1de0 [ 1288.032015] ? kernel_poison_pages+0x1b/0x250 [ 1288.032026] ? io_schedule_timeout+0x140/0x140 [ 1288.032034] ? __lock_acquire+0x5fc/0x3f20 [ 1288.032044] ? __down+0x124/0x260 [ 1288.032051] schedule+0x8d/0x1b0 [ 1288.032059] schedule_timeout+0x80a/0xe90 [ 1288.032066] ? __lock_acquire+0x5fc/0x3f20 [ 1288.032076] ? usleep_range+0x130/0x130 [ 1288.032083] ? trace_hardirqs_on+0x10/0x10 [ 1288.032091] ? __down+0x165/0x260 [ 1288.032102] ? lock_downgrade+0x740/0x740 [ 1288.032111] ? _raw_spin_unlock_irq+0x24/0x80 [ 1288.032121] ? __down+0x124/0x260 [ 1288.032128] __down+0x16d/0x260 [ 1288.032137] ? ww_mutex_lock+0x180/0x180 [ 1288.032150] down+0x57/0x80 [ 1288.032157] console_lock+0x24/0x70 [ 1288.032165] do_fb_ioctl+0x2e7/0xa70 [ 1288.032174] ? register_framebuffer+0x8e0/0x8e0 [ 1288.032185] ? avc_has_extended_perms+0x6e4/0xbf0 [ 1288.032195] ? _raw_spin_unlock+0x29/0x40 [ 1288.032203] ? avc_ss_reset+0x100/0x100 [ 1288.032215] ? tlb_flush_mmu_free+0x1a0/0x1a0 [ 1288.032223] ? __lock_acquire+0x5fc/0x3f20 [ 1288.032248] fb_ioctl+0xdd/0x130 [ 1288.032255] ? do_fb_ioctl+0xa70/0xa70 [ 1288.032264] do_vfs_ioctl+0x75a/0xff0 [ 1288.032272] ? selinux_inode_setxattr+0x730/0x730 [ 1288.032280] ? ioctl_preallocate+0x1a0/0x1a0 [ 1288.032292] ? lock_downgrade+0x740/0x740 [ 1288.032303] ? security_file_ioctl+0x83/0xb0 [ 1288.032313] SyS_ioctl+0x7f/0xb0 [ 1288.032320] ? do_vfs_ioctl+0xff0/0xff0 [ 1288.032329] do_syscall_64+0x1d5/0x640 [ 1288.032341] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1288.032346] RIP: 0033:0x4414e9 [ 1288.032350] RSP: 002b:00007ffe8b7eab28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1288.032357] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004414e9 [ 1288.032362] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 [ 1288.032366] RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8 [ 1288.032369] R10: 0000000000000004 R11: 0000000000000246 R12: 00000000004021e0 [ 1288.032434] R13: 0000000000402270 R14: 0000000000000000 R15: 0000000000000000 [ 1288.032454] INFO: task syz-executor714:6385 blocked for more than 140 seconds. [ 1288.032459] Not tainted 4.14.198-syzkaller #0 [ 1288.032462] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1288.032466] syz-executor714 D28912 6385 6380 0x00000004 [ 1288.032482] Call Trace: [ 1288.032496] __schedule+0x88b/0x1de0 [ 1288.032506] ? kernel_poison_pages+0x1b/0x250 [ 1288.032518] ? io_schedule_timeout+0x140/0x140 [ 1288.032526] ? __lock_acquire+0x5fc/0x3f20 [ 1288.032537] ? __down+0x124/0x260 [ 1288.032543] schedule+0x8d/0x1b0 [ 1288.032552] schedule_timeout+0x80a/0xe90 [ 1288.032560] ? __lock_acquire+0x5fc/0x3f20 [ 1288.032570] ? usleep_range+0x130/0x130 [ 1288.032577] ? trace_hardirqs_on+0x10/0x10 [ 1288.032585] ? __down+0x165/0x260 [ 1288.032597] ? lock_downgrade+0x740/0x740 [ 1288.032606] ? _raw_spin_unlock_irq+0x24/0x80 [ 1288.032616] ? __down+0x124/0x260 [ 1288.032623] __down+0x16d/0x260 [ 1288.032633] ? ww_mutex_lock+0x180/0x180 [ 1288.032646] down+0x57/0x80 [ 1288.032654] console_lock+0x24/0x70 [ 1288.032662] do_fb_ioctl+0x2e7/0xa70 [ 1288.032672] ? register_framebuffer+0x8e0/0x8e0 [ 1288.032701] ? avc_has_extended_perms+0x6e4/0xbf0 [ 1288.032712] ? _raw_spin_unlock+0x29/0x40 [ 1288.032733] ? avc_ss_reset+0x100/0x100 [ 1288.032747] ? tlb_flush_mmu_free+0x1a0/0x1a0 [ 1288.032756] ? __lock_acquire+0x5fc/0x3f20 [ 1288.032781] fb_ioctl+0xdd/0x130 [ 1288.032788] ? do_fb_ioctl+0xa70/0xa70 [ 1288.032797] do_vfs_ioctl+0x75a/0xff0 [ 1288.032806] ? selinux_inode_setxattr+0x730/0x730 [ 1288.032815] ? ioctl_preallocate+0x1a0/0x1a0 [ 1288.032827] ? lock_downgrade+0x740/0x740 [ 1288.032839] ? security_file_ioctl+0x83/0xb0 [ 1288.032849] SyS_ioctl+0x7f/0xb0 [ 1288.032856] ? do_vfs_ioctl+0xff0/0xff0 [ 1288.032866] do_syscall_64+0x1d5/0x640 [ 1288.032878] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1288.032884] RIP: 0033:0x4414e9 [ 1288.032888] RSP: 002b:00007ffe8b7eab28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1288.032896] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004414e9 [ 1288.032901] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 [ 1288.032906] RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8 [ 1288.032910] R10: 0000000000000004 R11: 0000000000000246 R12: 00000000004021e0 [ 1288.032914] R13: 0000000000402270 R14: 0000000000000000 R15: 0000000000000000 [ 1288.032930] INFO: task syz-executor714:6386 blocked for more than 140 seconds. [ 1288.032934] Not tainted 4.14.198-syzkaller #0 [ 1288.032937] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1288.032940] syz-executor714 D28912 6386 6378 0x00000004 [ 1288.032955] Call Trace: [ 1288.032965] __schedule+0x88b/0x1de0 [ 1288.032972] ? kernel_poison_pages+0x1b/0x250 [ 1288.032984] ? io_schedule_timeout+0x140/0x140 [ 1288.032991] ? __lock_acquire+0x5fc/0x3f20 [ 1288.033001] ? __down+0x124/0x260 [ 1288.033008] schedule+0x8d/0x1b0 [ 1288.033016] schedule_timeout+0x80a/0xe90 [ 1288.033024] ? __lock_acquire+0x5fc/0x3f20 [ 1288.033034] ? usleep_range+0x130/0x130 [ 1288.033041] ? trace_hardirqs_on+0x10/0x10 [ 1288.033049] ? __down+0x165/0x260 [ 1288.033060] ? lock_downgrade+0x740/0x740 [ 1288.033069] ? _raw_spin_unlock_irq+0x24/0x80 [ 1288.033079] ? __down+0x124/0x260 [ 1288.033086] __down+0x16d/0x260 [ 1288.033095] ? ww_mutex_lock+0x180/0x180 [ 1288.033108] down+0x57/0x80 [ 1288.033116] console_lock+0x24/0x70 [ 1288.033123] do_fb_ioctl+0x2e7/0xa70 [ 1288.033132] ? register_framebuffer+0x8e0/0x8e0 [ 1288.033143] ? avc_has_extended_perms+0x6e4/0xbf0 [ 1288.033154] ? _raw_spin_unlock+0x29/0x40 [ 1288.033167] ? avc_ss_reset+0x100/0x100 [ 1288.033180] ? tlb_flush_mmu_free+0x1a0/0x1a0 [ 1288.033188] ? __lock_acquire+0x5fc/0x3f20 [ 1288.033216] fb_ioctl+0xdd/0x130 [ 1288.033224] ? do_fb_ioctl+0xa70/0xa70 [ 1288.033232] do_vfs_ioctl+0x75a/0xff0 [ 1288.033240] ? selinux_inode_setxattr+0x730/0x730 [ 1288.033249] ? ioctl_preallocate+0x1a0/0x1a0 [ 1288.033261] ? lock_downgrade+0x740/0x740 [ 1288.033273] ? security_file_ioctl+0x83/0xb0 [ 1288.033283] SyS_ioctl+0x7f/0xb0 [ 1288.033290] ? do_vfs_ioctl+0xff0/0xff0 [ 1288.033316] do_syscall_64+0x1d5/0x640 [ 1288.033328] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1288.033334] RIP: 0033:0x4414e9 [ 1288.033338] RSP: 002b:00007ffe8b7eab28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1288.033345] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004414e9 [ 1288.033350] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 [ 1288.033363] RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8 [ 1288.033367] R10: 0000000000000004 R11: 0000000000000246 R12: 00000000004021e0 [ 1288.033372] R13: 0000000000402270 R14: 0000000000000000 R15: 0000000000000000 [ 1288.033387] INFO: task syz-executor714:6387 blocked for more than 140 seconds. [ 1288.033391] Not tainted 4.14.198-syzkaller #0 [ 1288.033394] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1288.033397] syz-executor714 D28912 6387 6376 0x00000004 [ 1288.033413] Call Trace: [ 1288.033424] __schedule+0x88b/0x1de0 [ 1288.033449] ? io_schedule_timeout+0x140/0x140 [ 1288.033456] ? lock_downgrade+0x740/0x740 [ 1288.033467] schedule+0x8d/0x1b0 [ 1288.033475] schedule_preempt_disabled+0xf/0x20 [ 1288.033483] __mutex_lock+0x669/0x1310 [ 1288.033494] ? fb_open+0xfb/0x4a0 [ 1288.033502] ? lock_downgrade+0x740/0x740 [ 1288.033511] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 1288.033522] ? __mutex_unlock_slowpath+0x75/0x770 [ 1288.033567] ? chrdev_open+0xf7/0x6d0 [ 1288.033579] ? lock_downgrade+0x740/0x740 [ 1288.033588] fb_open+0xfb/0x4a0 [ 1288.033598] ? fb_get_color_depth+0x200/0x200 [ 1288.033605] chrdev_open+0x23c/0x6d0 [ 1288.033615] ? __register_chrdev+0x3d0/0x3d0 [ 1288.033645] do_dentry_open+0x44b/0xec0 [ 1288.033653] ? __register_chrdev+0x3d0/0x3d0 [ 1288.033663] ? __inode_permission+0xcd/0x2f0 [ 1288.033672] vfs_open+0x105/0x220 [ 1288.033682] path_openat+0x628/0x2970 [ 1288.033696] ? path_lookupat+0x780/0x780 [ 1288.033705] ? trace_hardirqs_on+0x10/0x10 [ 1288.033719] do_filp_open+0x179/0x3c0 [ 1288.033727] ? may_open_dev+0xe0/0xe0 [ 1288.033759] ? lock_downgrade+0x740/0x740 [ 1288.033770] ? do_raw_spin_unlock+0x164/0x220 [ 1288.033793] ? _raw_spin_unlock+0x29/0x40 [ 1288.033807] ? __alloc_fd+0x1be/0x490 [ 1288.033819] do_sys_open+0x296/0x410 [ 1288.033828] ? filp_open+0x60/0x60 [ 1288.033856] ? __do_page_fault+0x19a/0xb50 [ 1288.033864] ? do_syscall_64+0x4c/0x640 [ 1288.033870] ? SyS_open+0x30/0x30 [ 1288.033879] do_syscall_64+0x1d5/0x640 [ 1288.033891] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1288.033896] RIP: 0033:0x4414e9 [ 1288.033900] RSP: 002b:00007ffe8b7eab28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 [ 1288.033908] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004414e9 [ 1288.033913] RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c [ 1288.033917] RBP: 00000000006cb018 R08: 0000000000000004 R09: 00000000004002c8 [ 1288.033921] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004021e0 [ 1288.033925] R13: 0000000000402270 R14: 0000000000000000 R15: 0000000000000000 [ 1288.033939] [ 1288.033939] Showing all locks held in the system: [ 1288.033947] 1 lock held by khungtaskd/1068: [ 1288.033951] #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a [ 1288.033987] 1 lock held by in:imklog/6004: [ 1288.033990] #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x1fb/0x2b0 [ 1288.034012] 1 lock held by syz-executor714/6387: [ 1288.034014] #0: (&fb_info->lock){+.+.}, at: [] fb_open+0xfb/0x4a0 [ 1288.034049] [ 1288.034051] ============================================= [ 1288.034051] [ 1288.034056] NMI backtrace for cpu 0 [ 1288.034063] CPU: 0 PID: 1068 Comm: khungtaskd Not tainted 4.14.198-syzkaller #0 [ 1288.034068] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1288.034070] Call Trace: [ 1288.034135] dump_stack+0x1b2/0x283 [ 1288.034180] nmi_cpu_backtrace.cold+0x57/0x93 [ 1288.034206] ? irq_force_complete_move.cold+0x7c/0x7c [ 1288.034216] nmi_trigger_cpumask_backtrace+0x13a/0x17f [ 1288.034243] watchdog+0x5b9/0xb40 [ 1288.034253] ? hungtask_pm_notify+0x50/0x50 [ 1288.034281] kthread+0x30d/0x420 [ 1288.034289] ? kthread_create_on_node+0xd0/0xd0 [ 1288.034297] ret_from_fork+0x24/0x30 [ 1288.034313] Sending NMI from CPU 0 to CPUs 1: [ 1288.034820] NMI backtrace for cpu 1 [ 1288.034824] CPU: 1 PID: 6383 Comm: syz-executor714 Not tainted 4.14.198-syzkaller #0 [ 1288.034828] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1288.034830] task: ffff888095a62340 task.stack: ffff888081fc8000 [ 1288.034833] RIP: 0010:__sanitizer_cov_trace_pc+0x23/0x50 [ 1288.034835] RSP: 0018:ffff888081fcf3d8 EFLAGS: 00000246 [ 1288.034840] RAX: ffff888095a62340 RBX: ffff8880000a0008 RCX: 0000000000000000 [ 1288.034843] RDX: 0000000000000000 RSI: ffff888081fcf470 RDI: ffff888081fcf480 [ 1288.034846] RBP: 0000000000000050 R08: 0000000000000001 R09: ffffed104324332b [ 1288.034849] R10: ffff88821921995f R11: 0000000000000000 R12: 0000000015cefdeb [ 1288.034851] R13: ffffffffffffffb0 R14: ffff8880000a0050 R15: 0000000000000000 [ 1288.034860] FS: 0000000001586880(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 [ 1288.034863] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1288.034865] CR2: 00000000006cc080 CR3: 00000000a0e84000 CR4: 00000000001406e0 [ 1288.034868] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1288.034871] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1288.034873] Call Trace: [ 1288.034875] vga16fb_fillrect+0x910/0x1820 [ 1288.034877] ? fb_copy_cmap+0x280/0x340 [ 1288.034879] ? vga16fb_setcolreg+0xfe/0x350 [ 1288.034881] bit_clear_margins+0x2a4/0x480 [ 1288.034895] ? bit_clear+0x450/0x450 [ 1288.034897] fbcon_clear_margins+0x1bb/0x300 [ 1288.034899] fbcon_switch+0xdb4/0x1b1f [ 1288.034901] ? fbcon_startup+0xef0/0xef0 [ 1288.034903] ? bit_update_start+0x1f0/0x1f0 [ 1288.034905] ? vga16fb_setcolreg+0xfe/0x350 [ 1288.034907] ? fbcon_set_origin+0x1c/0x40 [ 1288.034909] ? fbcon_scrolldelta+0x1170/0x1170 [ 1288.034910] redraw_screen+0x32c/0x790 [ 1288.034912] ? con_shutdown+0x90/0x90 [ 1288.034914] ? fbcon_set_palette+0x466/0x580 [ 1288.034916] fbcon_modechanged+0x68a/0x980 [ 1288.034918] fbcon_event_notify+0x107/0x1760 [ 1288.034920] notifier_call_chain+0x108/0x1a0 [ 1288.034922] blocking_notifier_call_chain+0x79/0x90 [ 1288.034924] fb_set_var+0xac5/0xc90 [ 1288.034926] ? fb_set_suspend+0x110/0x110 [ 1288.034928] ? __lock_acquire+0x5fc/0x3f20 [ 1288.034930] ? lock_acquire+0x170/0x3f0 [ 1288.034932] ? do_fb_ioctl+0x2f1/0xa70 [ 1288.034934] ? _raw_spin_unlock_irq+0x24/0x80 [ 1288.034936] ? do_fb_ioctl+0x2e7/0xa70 [ 1288.034937] do_fb_ioctl+0x36d/0xa70 [ 1288.034939] ? register_framebuffer+0x8e0/0x8e0 [ 1288.034942] ? avc_has_extended_perms+0x6e4/0xbf0 [ 1288.034944] ? _raw_spin_unlock+0x29/0x40 [ 1288.034945] ? avc_ss_reset+0x100/0x100 [ 1288.034947] ? tlb_flush_mmu_free+0x1a0/0x1a0 [ 1288.034949] fb_ioctl+0xdd/0x130 [ 1288.034951] ? do_fb_ioctl+0xa70/0xa70 [ 1288.034953] do_vfs_ioctl+0x75a/0xff0 [ 1288.034955] ? selinux_inode_setxattr+0x730/0x730 [ 1288.034957] ? ioctl_preallocate+0x1a0/0x1a0 [ 1288.034959] ? lock_downgrade+0x740/0x740 [ 1288.034961] ? security_file_ioctl+0x83/0xb0 [ 1288.034963] SyS_ioctl+0x7f/0xb0 [ 1288.034964] ? do_vfs_ioctl+0xff0/0xff0 [ 1288.034966] do_syscall_64+0x1d5/0x640 [ 1288.034969] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 1288.034970] RIP: 0033:0x4414e9 [ 1288.034972] RSP: 002b:00007ffe8b7eab28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1288.034977] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004414e9 [ 1288.034980] RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 [ 1288.034983] RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8 [ 1288.034986] R10: 0000000000000004 R11: 0000000000000246 R12: 00000000004021e0 [ 1288.034989] R13: 0000000000402270 R14: 0000000000000000 R15: 0000000000000000 [ 1288.034990] Code: 00 00 e9 c6 ed ff ff 90 65 48 8b 04 25 40 ee 01 00 48 85 c0 74 1a 65 8b 15 ab 56 a6 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 [ 1288.035326] Kernel panic - not syncing: hung_task: blocked tasks [ 1288.035332] CPU: 0 PID: 1068 Comm: khungtaskd Not tainted 4.14.198-syzkaller #0 [ 1288.035337] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1288.035339] Call Trace: [ 1288.035347] dump_stack+0x1b2/0x283 [ 1288.035402] panic+0x1f9/0x42d [ 1288.035410] ? add_taint.cold+0x16/0x16 [ 1288.035419] ? printk_safe_flush+0xa9/0x110 [ 1288.035431] watchdog+0x5ca/0xb40 [ 1288.035440] ? hungtask_pm_notify+0x50/0x50 [ 1288.035448] kthread+0x30d/0x420 [ 1288.035455] ? kthread_create_on_node+0xd0/0xd0 [ 1288.035463] ret_from_fork+0x24/0x30 [ 1288.037399] Kernel Offset: disabled