[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 38.232274] random: sshd: uninitialized urandom read (32 bytes read) [ 38.646490] kauditd_printk_skb: 10 callbacks suppressed [ 38.646497] audit: type=1400 audit(1576436352.980:35): avc: denied { map } for pid=7049 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 38.693730] random: sshd: uninitialized urandom read (32 bytes read) [ 39.277694] random: sshd: uninitialized urandom read (32 bytes read) [ 698.203321] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.1' (ECDSA) to the list of known hosts. [ 703.891440] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program [ 704.013461] audit: type=1400 audit(1576437018.350:36): avc: denied { map } for pid=7061 comm="syz-executor206" path="/root/syz-executor206169426" dev="sda1" ino=1426 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 1001.440196] INFO: task login:7038 blocked for more than 140 seconds. [ 1001.446838] Not tainted 4.14.158-syzkaller #0 [ 1001.452293] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1001.460300] login D25920 7038 1 0x80000002 [ 1001.465934] Call Trace: [ 1001.468610] __schedule+0x7b8/0x1cd0 [ 1001.475996] ? firmware_map_remove+0x196/0x196 [ 1001.480698] ? trace_hardirqs_on+0x10/0x10 [ 1001.484956] schedule+0x92/0x1c0 [ 1001.488321] schedule_timeout+0x93b/0xe10 [ 1001.492840] ? __ldsem_down_write_nested+0x2fc/0x7b0 [ 1001.500671] ? find_held_lock+0x35/0x130 [ 1001.504729] ? usleep_range+0x130/0x130 [ 1001.508698] ? __ldsem_down_write_nested+0x2fc/0x7b0 [ 1001.514239] ? mark_held_locks+0xb1/0x100 [ 1001.518389] ? _raw_spin_unlock_irq+0x28/0x90 [ 1001.523115] ? trace_hardirqs_on_caller+0x400/0x590 [ 1001.528133] __ldsem_down_write_nested+0x304/0x7b0 [ 1001.533282] ? __ldsem_down_read_nested+0x5d0/0x5d0 [ 1001.538297] ? __wake_up_common_lock+0xe3/0x160 [ 1001.543192] ldsem_down_write+0x33/0x39 [ 1001.547163] ? ldsem_down_write+0x33/0x39 [ 1001.552184] tty_ldisc_lock+0x1e/0x50 [ 1001.555985] tty_ldisc_hangup+0x1a5/0x5e0 [ 1001.560410] __tty_hangup.part.0+0x2d3/0x6d0 [ 1001.564823] ? tty_read+0x270/0x270 [ 1001.568449] tty_vhangup_session+0x25/0x30 [ 1001.573357] disassociate_ctty.part.0+0x9b/0x6c0 [ 1001.578214] disassociate_ctty+0x78/0x90 [ 1001.582848] do_exit+0x1799/0x2c80 [ 1001.586430] ? security_file_permission+0x89/0x1f0 [ 1001.591696] ? rw_verify_area+0xea/0x2b0 [ 1001.595936] ? mm_update_next_owner+0x5d0/0x5d0 [ 1001.600905] ? vfs_write+0x104/0x500 [ 1001.604626] ? SyS_write+0x15e/0x230 [ 1001.608348] do_group_exit+0x111/0x330 [ 1001.612601] SyS_exit_group+0x1d/0x20 [ 1001.616411] ? do_group_exit+0x330/0x330 [ 1001.620707] do_syscall_64+0x1e8/0x640 [ 1001.624590] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 1001.629442] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 1001.635083] RIP: 0033:0x7f674a99a1e8 [ 1001.638806] RSP: 002b:00007ffe85c99c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 1001.647011] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f674a99a1e8 [ 1001.654753] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 1001.662406] RBP: 00007f674ac6f840 R08: 00000000000000e7 R09: ffffffffffffffa8 [ 1001.669697] R10: 00007f674ac75740 R11: 0000000000000246 R12: 00007f674ac6f840 [ 1001.677231] R13: 0000000000000001 R14: 0000000000000001 R15: 000000000060b798 [ 1001.685216] [ 1001.685216] Showing all locks held in the system: [ 1001.691783] 1 lock held by khungtaskd/1045: [ 1001.696191] #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f [ 1001.705387] 2 locks held by login/7038: [ 1001.709348] #0: (&tty->legacy_mutex){+.+.}, at: [] tty_lock+0x68/0x80 [ 1001.717789] #1: (&tty->ldisc_sem){++++}, at: [] ldsem_down_write+0x33/0x39 [ 1001.726587] 2 locks held by getty/7039: [ 1001.730579] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 1001.739278] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 1001.748598] 2 locks held by getty/7040: [ 1001.752588] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 1001.761289] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 1001.770683] 2 locks held by getty/7041: [ 1001.774654] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 1001.783395] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 1001.800750] 2 locks held by getty/7042: [ 1001.804731] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 1001.813495] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 1001.822916] 2 locks held by getty/7043: [ 1001.826894] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 1001.835630] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 1001.844979] 2 locks held by getty/7044: [ 1001.848943] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 1001.857649] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 1001.866995] [ 1001.868615] ============================================= [ 1001.868615] [ 1001.876800] NMI backtrace for cpu 0 [ 1001.880476] CPU: 0 PID: 1045 Comm: khungtaskd Not tainted 4.14.158-syzkaller #0 [ 1001.887912] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1001.897256] Call Trace: [ 1001.899930] dump_stack+0x142/0x197 [ 1001.903588] nmi_cpu_backtrace.cold+0x57/0x94 [ 1001.908293] ? irq_force_complete_move.cold+0x7d/0x7d [ 1001.913740] nmi_trigger_cpumask_backtrace+0x141/0x189 [ 1001.919723] arch_trigger_cpumask_backtrace+0x14/0x20 [ 1001.925405] watchdog+0x5e7/0xb90 [ 1001.929210] kthread+0x319/0x430 [ 1001.932609] ? hungtask_pm_notify+0x50/0x50 [ 1001.936927] ? kthread_create_on_node+0xd0/0xd0 [ 1001.941640] ret_from_fork+0x24/0x30 [ 1001.945456] Sending NMI from CPU 0 to CPUs 1: [ 1001.950497] NMI backtrace for cpu 1 [ 1001.950501] CPU: 1 PID: 7132 Comm: syz-executor206 Not tainted 4.14.158-syzkaller #0 [ 1001.950505] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1001.950507] task: ffff88808582c200 task.stack: ffff8880a0318000 [ 1001.950510] RIP: 0010:rcu_preempt_qs+0x2b/0x110 [ 1001.950512] RSP: 0018:ffff8880a031f850 EFLAGS: 00000096 [ 1001.950516] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff1066f80 [ 1001.950520] RDX: 0000000000000000 RSI: ffffffff86cba620 RDI: ffffffff87040d00 [ 1001.950523] RBP: ffff8880a031f858 R08: ffff88808582c200 R09: ffff88808582cac8 [ 1001.950526] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 1001.950528] R13: ffff88808582c200 R14: ffff88808582c200 R15: ffff8880aed2b540 [ 1001.950532] FS: 0000000000a0b880(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 [ 1001.950534] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1001.950537] CR2: 000000000203b000 CR3: 00000000a3a24000 CR4: 00000000001406e0 [ 1001.950540] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1001.950543] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1001.950545] Call Trace: [ 1001.950547] rcu_note_context_switch+0xde/0x1600 [ 1001.950549] ? __lock_is_held+0xb6/0x140 [ 1001.950552] ? nf_log_arp_packet+0x510/0x5d0 [ 1001.950553] __schedule+0x1d2/0x1cd0 [ 1001.950556] ? firmware_map_remove+0x196/0x196 [ 1001.950558] ? preempt_count_sub+0xb3/0x130 [ 1001.950560] schedule+0x92/0x1c0 [ 1001.950562] paste_selection+0x293/0x3f2 [ 1001.950564] ? find_held_lock+0x35/0x130 [ 1001.950567] ? set_selection+0xe30/0xe30 [ 1001.950569] ? lock_downgrade+0x740/0x740 [ 1001.950571] ? wake_up_q+0xf0/0xf0 [ 1001.950573] tioclinux+0x10e/0x400 [ 1001.950575] vt_ioctl+0x180c/0x2170 [ 1001.950577] ? avc_has_extended_perms+0x8ec/0xe40 [ 1001.950579] ? complete_change_console+0x360/0x360 [ 1001.950581] ? avc_ss_reset+0x110/0x110 [ 1001.950583] ? do_raw_spin_unlock+0x16b/0x260 [ 1001.950585] ? tty_jobctrl_ioctl+0x44/0xc10 [ 1001.950587] ? _raw_spin_unlock+0x2d/0x50 [ 1001.950590] ? complete_change_console+0x360/0x360 [ 1001.950592] tty_ioctl+0x841/0x1320 [ 1001.950594] ? tty_vhangup+0x30/0x30 [ 1001.950596] ? __might_sleep+0x93/0xb0 [ 1001.950598] ? save_trace+0x290/0x290 [ 1001.950600] ? tty_vhangup+0x30/0x30 [ 1001.950602] do_vfs_ioctl+0x7ae/0x1060 [ 1001.950604] ? selinux_file_mprotect+0x5d0/0x5d0 [ 1001.950606] ? ioctl_preallocate+0x1c0/0x1c0 [ 1001.950608] ? lock_downgrade+0x740/0x740 [ 1001.950611] ? security_file_ioctl+0x7d/0xb0 [ 1001.950613] ? security_file_ioctl+0x89/0xb0 [ 1001.950615] SyS_ioctl+0x8f/0xc0 [ 1001.950617] ? do_vfs_ioctl+0x1060/0x1060 [ 1001.950619] do_syscall_64+0x1e8/0x640 [ 1001.950621] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 1001.950623] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 1001.950625] RIP: 0033:0x441209 [ 1001.950628] RSP: 002b:00007ffd559be178 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1001.950632] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441209 [ 1001.950636] RDX: 0000000020000080 RSI: 000000000000541c RDI: 0000000000000003 [ 1001.950639] RBP: 00000000000acc9c R08: 00000000004002c8 R09: 00000000004002c8 [ 1001.950641] R10: 000000000000000d R11: 0000000000000246 R12: 0000000000402030 [ 1001.950644] R13: 00000000004020c0 R14: 0000000000000000 R15: 0000000000000000 [ 1001.950646] Code: 55 48 89 e5 53 e8 66 27 ff ff 85 c0 74 09 80 3d 32 5b 5f 07 00 74 1c 48 c7 c7 20 a6 cb 86 e8 ad 97 bc 01 65 66 8b 05 2d 67 b4 7e <66> 85 c0 75 6e 5b 5d c3 65 8b 05 96 93 b3 7e a9 ff ff ff 7f 75 [ 1001.951292] Kernel panic - not syncing: hung_task: blocked tasks [ 1002.292776] CPU: 0 PID: 1045 Comm: khungtaskd Not tainted 4.14.158-syzkaller #0 [ 1002.300651] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 1002.310012] Call Trace: [ 1002.312695] dump_stack+0x142/0x197 [ 1002.316333] panic+0x1f9/0x42d [ 1002.319520] ? add_taint.cold+0x16/0x16 [ 1002.323486] ? ___preempt_schedule+0x16/0x18 [ 1002.327907] watchdog+0x5f8/0xb90 [ 1002.336488] kthread+0x319/0x430 [ 1002.339857] ? hungtask_pm_notify+0x50/0x50 [ 1002.344194] ? kthread_create_on_node+0xd0/0xd0 [ 1002.348874] ret_from_fork+0x24/0x30 [ 1002.354349] Kernel Offset: disabled [ 1002.357996] Rebooting in 86400 seconds..