[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 25.505768] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 29.177931] random: sshd: uninitialized urandom read (32 bytes read) [ 29.420753] random: sshd: uninitialized urandom read (32 bytes read) [ 30.079493] random: sshd: uninitialized urandom read (32 bytes read) [ 395.946608] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.36' (ECDSA) to the list of known hosts. [ 401.516621] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program [ 554.903504] INFO: task syz-executor630:5364 blocked for more than 140 seconds. [ 554.911221] Not tainted 4.19.0-rc4+ #27 [ 554.916549] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 554.924665] syz-executor630 D25176 5364 5349 0x00000004 [ 554.930303] Call Trace: [ 554.933007] __schedule+0x86c/0x1ed0 [ 554.936805] ? __switch_to_asm+0x34/0x70 [ 554.940858] ? __switch_to_asm+0x34/0x70 [ 554.944977] ? __sched_text_start+0x8/0x8 [ 554.949114] ? _raw_spin_unlock+0x2c/0x50 [ 554.953301] ? __sched_text_start+0x8/0x8 [ 554.957507] ? max_active_store+0x170/0x170 [ 554.961862] ? is_bpf_text_address+0xd3/0x170 [ 554.966454] ? graph_lock+0x170/0x170 [ 554.970252] schedule+0xfe/0x460 [ 554.973695] ? __local_bh_enable_ip+0x160/0x260 [ 554.978415] ? __schedule+0x1ed0/0x1ed0 [ 554.982384] ? find_held_lock+0x36/0x1c0 [ 554.986575] ? mark_held_locks+0xc7/0x130 [ 554.990817] schedule_timeout+0x1cc/0x260 [ 554.995028] ? usleep_range+0x1a0/0x1a0 [ 554.999004] ? wait_for_completion+0x41f/0x8a0 [ 555.003712] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 555.009260] ? kasan_check_write+0x14/0x20 [ 555.013560] ? do_raw_spin_lock+0xc1/0x200 [ 555.017792] wait_for_completion+0x427/0x8a0 [ 555.022190] ? wait_for_completion_interruptible+0x840/0x840 [ 555.028094] ? wake_up_q+0x100/0x100 [ 555.031868] ? pcrypt_aead_enc+0x190/0x190 [ 555.036171] ? rcu_read_lock_sched_held+0x108/0x120 [ 555.041203] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 555.046801] ? pcrypt_aead_encrypt+0x370/0x460 [ 555.051438] tls_push_record+0xf96/0x1480 [ 555.055682] ? check_preemption_disabled+0x48/0x200 [ 555.060709] tls_sw_sendmsg+0xbfd/0x1310 [ 555.064805] ? trace_hardirqs_on+0xbd/0x310 [ 555.069128] ? decrypt_skb_update+0x6a0/0x6a0 [ 555.073769] ? smack_socket_getpeersec_stream+0x1d0/0x1d0 [ 555.079341] ? usercopy_warn+0x110/0x110 [ 555.083461] inet_sendmsg+0x1a1/0x690 [ 555.087257] ? ipip_gro_receive+0x100/0x100 [ 555.091591] ? smack_socket_sendmsg+0xb0/0x190 [ 555.096218] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 555.101768] ? security_socket_sendmsg+0x94/0xc0 [ 555.106578] ? ipip_gro_receive+0x100/0x100 [ 555.110977] sock_sendmsg+0xd5/0x120 [ 555.114732] __sys_sendto+0x3d7/0x670 [ 555.118523] ? __ia32_sys_getpeername+0xb0/0xb0 [ 555.123178] ? _raw_spin_unlock_bh+0x30/0x40 [ 555.127644] ? release_sock+0x1ec/0x2c0 [ 555.131614] ? tls_sw_free_resources_rx+0x80/0x80 [ 555.136498] ? __release_sock+0x3a0/0x3a0 [ 555.140695] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 555.146349] ? _copy_from_user+0xdf/0x150 [ 555.150509] ? sk_stream_wait_memory+0x1290/0x1290 [ 555.155480] ? tls_setsockopt+0xb2/0x770 [ 555.159538] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 555.165162] ? do_syscall_64+0x9a/0x820 [ 555.169132] ? do_syscall_64+0x9a/0x820 [ 555.173099] ? lockdep_hardirqs_on+0x421/0x5c0 [ 555.177787] ? trace_hardirqs_on+0xbd/0x310 [ 555.182161] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 555.187591] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 555.193168] __x64_sys_sendto+0xe1/0x1a0 [ 555.197292] do_syscall_64+0x1b9/0x820 [ 555.201181] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 555.206602] ? syscall_return_slowpath+0x5e0/0x5e0 [ 555.211522] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 555.216409] ? trace_hardirqs_on_caller+0x310/0x310 [ 555.221419] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 555.226477] ? prepare_exit_to_usermode+0x291/0x3b0 [ 555.231496] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 555.236392] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 555.241616] RIP: 0033:0x440fd9 [ 555.244874] Code: 68 65 72 65 20 61 72 65 20 6e 6f 20 61 63 74 69 76 65 20 61 63 74 69 6f 6e 73 20 63 6f 6e 66 69 67 75 72 65 64 2e 20 49 6e 70 <75> 74 73 20 77 69 6c 6c 20 72 75 6e 2c 20 62 75 74 20 6e 6f 20 6f [ 555.263934] RSP: 002b:00007fff2d150978 EFLAGS: 00000216 ORIG_RAX: 000000000000002c [ 555.271632] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440fd9 [ 555.278953] RDX: 00000000000000b4 RSI: 0000000020000200 RDI: 0000000000000003 [ 555.286239] RBP: 0000000000000000 R08: 0000000020000040 R09: 000000000000001c [ 555.293541] R10: 0000000000000000 R11: 0000000000000216 R12: 00000000000620fc [ 555.300797] R13: 0000000000401fb0 R14: 0000000000000000 R15: 0000000000000000 [ 555.308106] [ 555.308106] Showing all locks held in the system: [ 555.314462] 1 lock held by khungtaskd/983: [ 555.318681] #0: 00000000c5c3673e (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 [ 555.327354] 1 lock held by rsyslogd/5227: [ 555.331487] #0: 000000002c662c45 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 [ 555.339609] 2 locks held by getty/5317: [ 555.343596] #0: 00000000a7df1347 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 555.351843] #1: 000000004e2bd6b9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 555.360850] 2 locks held by getty/5318: [ 555.364839] #0: 000000001f256084 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 555.373081] #1: 000000002fc7b522 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 555.381982] 2 locks held by getty/5319: [ 555.385975] #0: 00000000c234f0e1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 555.394274] #1: 00000000944e1b42 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 555.403119] 2 locks held by getty/5320: [ 555.407113] #0: 00000000f2d98e44 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 555.415379] #1: 000000008ffb783d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 555.424271] 2 locks held by getty/5321: [ 555.428227] #0: 0000000053d195e7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 555.436513] #1: 00000000bff8714a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 555.445409] 2 locks held by getty/5322: [ 555.449362] #0: 00000000e63ee762 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 555.457654] #1: 000000008e693bcc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 555.466537] 2 locks held by getty/5323: [ 555.470566] #0: 00000000d96cfc4c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 [ 555.478865] #1: 000000008004b0ef (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 [ 555.487756] 1 lock held by syz-executor630/5364: [ 555.492491] #0: 000000006ac37c29 (sk_lock-AF_INET6){+.+.}, at: tls_sw_sendmsg+0x226/0x1310 [ 555.501063] [ 555.502678] ============================================= [ 555.502678] [ 555.509724] NMI backtrace for cpu 0 [ 555.513369] CPU: 0 PID: 983 Comm: khungtaskd Not tainted 4.19.0-rc4+ #27 [ 555.520189] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 555.529520] Call Trace: [ 555.532182] dump_stack+0x1c4/0x2b4 [ 555.535800] ? dump_stack_print_info.cold.2+0x52/0x52 [ 555.540983] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 555.546507] nmi_cpu_backtrace.cold.3+0x63/0xa2 [ 555.551205] ? lapic_can_unplug_cpu.cold.27+0x3f/0x3f [ 555.556383] nmi_trigger_cpumask_backtrace+0x1b3/0x1ed [ 555.561674] arch_trigger_cpumask_backtrace+0x14/0x20 [ 555.566846] watchdog+0xb3e/0x1050 [ 555.570375] ? reset_hung_task_detector+0xd0/0xd0 [ 555.575201] ? __kthread_parkme+0xce/0x1a0 [ 555.579420] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 555.584537] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 555.589625] ? lockdep_hardirqs_on+0x421/0x5c0 [ 555.594192] ? trace_hardirqs_on+0xbd/0x310 [ 555.598573] ? kasan_check_read+0x11/0x20 [ 555.602714] ? __kthread_parkme+0xce/0x1a0 [ 555.606948] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 555.612411] ? kasan_check_write+0x14/0x20 [ 555.616641] ? do_raw_spin_lock+0xc1/0x200 [ 555.620863] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 555.625956] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 555.631478] ? __kthread_parkme+0xfb/0x1a0 [ 555.635701] kthread+0x35a/0x420 [ 555.639056] ? reset_hung_task_detector+0xd0/0xd0 [ 555.643889] ? kthread_bind+0x40/0x40 [ 555.647702] ret_from_fork+0x3a/0x50 [ 555.651559] Sending NMI from CPU 0 to CPUs 1: [ 555.656168] NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 [ 555.657402] Kernel panic - not syncing: hung_task: blocked tasks [ 555.669878] CPU: 0 PID: 983 Comm: khungtaskd Not tainted 4.19.0-rc4+ #27 [ 555.676701] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 555.686037] Call Trace: [ 555.688611] dump_stack+0x1c4/0x2b4 [ 555.692226] ? dump_stack_print_info.cold.2+0x52/0x52 [ 555.697407] panic+0x238/0x4e7 [ 555.700582] ? add_taint.cold.5+0x16/0x16 [ 555.704718] ? nmi_trigger_cpumask_backtrace+0x16a/0x1ed [ 555.710150] ? nmi_trigger_cpumask_backtrace+0x1c4/0x1ed [ 555.715581] ? nmi_trigger_cpumask_backtrace+0x173/0x1ed [ 555.721017] ? nmi_trigger_cpumask_backtrace+0x16a/0x1ed [ 555.726454] watchdog+0xb4f/0x1050 [ 555.729984] ? reset_hung_task_detector+0xd0/0xd0 [ 555.734815] ? __kthread_parkme+0xce/0x1a0 [ 555.739033] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 555.744122] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 555.749266] ? lockdep_hardirqs_on+0x421/0x5c0 [ 555.753844] ? trace_hardirqs_on+0xbd/0x310 [ 555.758155] ? kasan_check_read+0x11/0x20 [ 555.762286] ? __kthread_parkme+0xce/0x1a0 [ 555.766559] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 555.772005] ? kasan_check_write+0x14/0x20 [ 555.776224] ? do_raw_spin_lock+0xc1/0x200 [ 555.780445] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 555.785537] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 555.791062] ? __kthread_parkme+0xfb/0x1a0 [ 555.795288] kthread+0x35a/0x420 [ 555.798640] ? reset_hung_task_detector+0xd0/0xd0 [ 555.803462] ? kthread_bind+0x40/0x40 [ 555.807249] ret_from_fork+0x3a/0x50 [ 555.812151] Kernel Offset: disabled [ 555.815779] Rebooting in 86400 seconds..