[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.441932] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.218187] random: sshd: uninitialized urandom read (32 bytes read) [ 22.618432] random: sshd: uninitialized urandom read (32 bytes read) [ 23.405197] random: sshd: uninitialized urandom read (32 bytes read) [ 23.559502] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.39' (ECDSA) to the list of known hosts. [ 29.061555] random: sshd: uninitialized urandom read (32 bytes read) 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 [ 29.192261] ================================================================== [ 29.199781] BUG: KASAN: user-memory-access in n_tty_set_termios+0x106/0xe80 [ 29.206894] Write of size 512 at addr 0000000000001060 by task syz-executor526/4529 [ 29.214690] [ 29.216337] CPU: 1 PID: 4529 Comm: syz-executor526 Not tainted 4.17.0-rc5+ #58 [ 29.223704] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.233069] Call Trace: [ 29.235676] dump_stack+0x1b9/0x294 [ 29.239332] ? dump_stack_print_info.cold.2+0x52/0x52 [ 29.244542] ? kasan_check_write+0x14/0x20 [ 29.248797] ? do_raw_spin_lock+0xc1/0x200 [ 29.253053] ? vprintk_func+0x81/0xe7 [ 29.256872] ? n_tty_set_termios+0x106/0xe80 [ 29.261301] kasan_report.cold.7+0x6d/0x2fe [ 29.265647] check_memory_region+0x13e/0x1b0 [ 29.270073] memset+0x23/0x40 [ 29.273201] n_tty_set_termios+0x106/0xe80 [ 29.277457] ? n_tty_receive_signal_char+0x120/0x120 [ 29.282577] tty_set_termios+0x7a0/0xac0 [ 29.286668] ? tty_wait_until_sent+0x5b0/0x5b0 [ 29.291281] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 29.296836] ? ldsem_up_read+0x54/0x90 [ 29.300750] set_termios+0x41e/0x7d0 [ 29.304485] ? tty_perform_flush+0x80/0x80 [ 29.308749] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 29.314312] tty_mode_ioctl+0x855/0xb50 [ 29.318311] ? set_termios+0x7d0/0x7d0 [ 29.322397] ? check_same_owner+0x320/0x320 [ 29.326735] ? exit_robust_list+0x290/0x290 [ 29.331100] n_tty_ioctl_helper+0x54/0x3b0 [ 29.335354] n_tty_ioctl+0x54/0x320 [ 29.338991] ? ldsem_down_read+0x37/0x40 [ 29.343064] ? ldsem_down_read+0x37/0x40 [ 29.347145] tty_ioctl+0x5e1/0x1870 [ 29.350788] ? commit_echoes+0x1d0/0x1d0 [ 29.354865] ? tty_vhangup+0x30/0x30 [ 29.358583] ? rcu_is_watching+0x85/0x140 [ 29.362739] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 29.367937] ? __fget+0x40c/0x650 [ 29.371435] ? expand_files.part.8+0x9a0/0x9a0 [ 29.376037] ? trace_hardirqs_off+0xd/0x10 [ 29.380288] ? _raw_spin_unlock_irqrestore+0x63/0xc0 [ 29.385478] ? tty_vhangup+0x30/0x30 [ 29.389217] do_vfs_ioctl+0x1cf/0x16a0 [ 29.393130] ? ioctl_preallocate+0x2e0/0x2e0 [ 29.398239] ? fget_raw+0x20/0x20 [ 29.401714] ? kmem_cache_free+0x25c/0x2d0 [ 29.405976] ? __x64_sys_futex+0x477/0x680 [ 29.410217] ? exit_to_usermode_loop+0x87/0x310 [ 29.414886] ? do_futex+0x27d0/0x27d0 [ 29.418703] ? security_file_ioctl+0x94/0xc0 [ 29.423137] ksys_ioctl+0xa9/0xd0 [ 29.426614] __x64_sys_ioctl+0x73/0xb0 [ 29.430522] do_syscall_64+0x1b1/0x800 [ 29.434415] ? finish_task_switch+0x1ca/0x840 [ 29.438906] ? syscall_return_slowpath+0x5c0/0x5c0 [ 29.443843] ? syscall_return_slowpath+0x30f/0x5c0 [ 29.448790] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 29.454185] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.459056] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 29.464253] RIP: 0033:0x445cf9 [ 29.467444] RSP: 002b:00007f1e5d890d18 EFLAGS: 00000297 ORIG_RAX: 0000000000000010 [ 29.475158] RAX: ffffffffffffffda RBX: 00000000006dac24 RCX: 0000000000445cf9 [ 29.482431] RDX: 0000000020000040 RSI: 0000000000005402 RDI: 0000000000000006 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 [ 29.489695] RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000 [ 29.496955] R10: 0000000000000000 R11: 0000000000000297 R12: 6d74702f7665642f [ 29.504213] R13: 00007ffdf1446d9f R14: 00007f1e5d8919c0 R15: 0000000000000007 [ 29.511490] ================================================================== [ 29.518835] Disabling lock debugging due to kernel taint [ 29.524388] Kernel panic - not syncing: panic_on_warn set ... [ 29.524388] [ 29.531758] CPU: 1 PID: 4529 Comm: syz-executor526 Tainted: G B 4.17.0-rc5+ #58 [ 29.540498] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.549853] Call Trace: [ 29.552442] dump_stack+0x1b9/0x294 [ 29.556057] ? dump_stack_print_info.cold.2+0x52/0x52 [ 29.561242] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.565990] ? n_tty_set_termios+0x70/0xe80 [ 29.570302] panic+0x22f/0x4de [ 29.573494] ? add_taint.cold.5+0x16/0x16 [ 29.577635] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.582039] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.586440] ? n_tty_set_termios+0x106/0xe80 [ 29.590847] kasan_end_report+0x47/0x4f [ 29.594812] kasan_report.cold.7+0x76/0x2fe [ 29.599130] check_memory_region+0x13e/0x1b0 [ 29.603524] memset+0x23/0x40 [ 29.606625] n_tty_set_termios+0x106/0xe80 [ 29.610851] ? n_tty_receive_signal_char+0x120/0x120 [ 29.615951] tty_set_termios+0x7a0/0xac0 [ 29.620011] ? tty_wait_until_sent+0x5b0/0x5b0 [ 29.624605] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 29.630129] ? ldsem_up_read+0x54/0x90 [ 29.634010] set_termios+0x41e/0x7d0 [ 29.637727] ? tty_perform_flush+0x80/0x80 [ 29.641964] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 29.647509] tty_mode_ioctl+0x855/0xb50 [ 29.651501] ? set_termios+0x7d0/0x7d0 [ 29.655410] ? check_same_owner+0x320/0x320 [ 29.659739] ? exit_robust_list+0x290/0x290 [ 29.664077] n_tty_ioctl_helper+0x54/0x3b0 [ 29.668322] n_tty_ioctl+0x54/0x320 [ 29.671968] ? ldsem_down_read+0x37/0x40 [ 29.676035] ? ldsem_down_read+0x37/0x40 [ 29.680108] tty_ioctl+0x5e1/0x1870 [ 29.683747] ? commit_echoes+0x1d0/0x1d0 [ 29.687819] ? tty_vhangup+0x30/0x30 [ 29.691543] ? rcu_is_watching+0x85/0x140 [ 29.695704] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 29.700915] ? __fget+0x40c/0x650 [ 29.704387] ? expand_files.part.8+0x9a0/0x9a0 [ 29.708980] ? trace_hardirqs_off+0xd/0x10 [ 29.713227] ? _raw_spin_unlock_irqrestore+0x63/0xc0 [ 29.718347] ? tty_vhangup+0x30/0x30 [ 29.722068] do_vfs_ioctl+0x1cf/0x16a0 [ 29.725968] ? ioctl_preallocate+0x2e0/0x2e0 [ 29.730383] ? fget_raw+0x20/0x20 [ 29.733845] ? kmem_cache_free+0x25c/0x2d0 [ 29.738094] ? __x64_sys_futex+0x477/0x680 [ 29.742353] ? exit_to_usermode_loop+0x87/0x310 [ 29.747036] ? do_futex+0x27d0/0x27d0 [ 29.750845] ? security_file_ioctl+0x94/0xc0 [ 29.755270] ksys_ioctl+0xa9/0xd0 [ 29.758734] __x64_sys_ioctl+0x73/0xb0 [ 29.762631] do_syscall_64+0x1b1/0x800 [ 29.766524] ? finish_task_switch+0x1ca/0x840 [ 29.771030] ? syscall_return_slowpath+0x5c0/0x5c0 [ 29.775972] ? syscall_return_slowpath+0x30f/0x5c0 [ 29.780913] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 29.786292] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.791149] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 29.796345] RIP: 0033:0x445cf9 [ 29.799534] RSP: 002b:00007f1e5d890d18 EFLAGS: 00000297 ORIG_RAX: 0000000000000010 [ 29.807252] RAX: ffffffffffffffda RBX: 00000000006dac24 RCX: 0000000000445cf9 [ 29.814527] RDX: 0000000020000040 RSI: 0000000000005402 RDI: 0000000000000006 [ 29.821810] RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000 [ 29.829081] R10: 0000000000000000 R11: 0000000000000297 R12: 6d74702f7665642f [ 29.836356] R13: 00007ffdf1446d9f R14: 00007f1e5d8919c0 R15: 0000000000000007 [ 29.844207] Dumping ftrace buffer: [ 29.847735] (ftrace buffer empty) [ 29.851457] Kernel Offset: disabled [ 29.855080] Rebooting in 86400 seconds..