[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.027327] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.636160] random: sshd: uninitialized urandom read (32 bytes read) [ 22.998942] random: sshd: uninitialized urandom read (32 bytes read) [ 23.791651] random: sshd: uninitialized urandom read (32 bytes read) [ 23.956554] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.9' (ECDSA) to the list of known hosts. [ 29.858088] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 29.948904] ================================================================== [ 29.956356] BUG: KASAN: slab-out-of-bounds in strlen+0x83/0xa0 [ 29.962324] Read of size 1 at addr ffff8801d7039258 by task syz-executor745/4503 [ 29.969871] [ 29.971486] CPU: 0 PID: 4503 Comm: syz-executor745 Not tainted 4.17.0-rc7+ #78 [ 29.978911] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.988260] Call Trace: [ 29.990846] dump_stack+0x1b9/0x294 [ 29.994631] ? dump_stack_print_info.cold.2+0x52/0x52 [ 29.999804] ? printk+0x9e/0xba [ 30.003085] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 30.007825] ? kasan_check_write+0x14/0x20 [ 30.012047] print_address_description+0x6c/0x20b [ 30.016875] ? strlen+0x83/0xa0 [ 30.020139] kasan_report.cold.7+0x242/0x2fe [ 30.024549] __asan_report_load1_noabort+0x14/0x20 [ 30.029463] strlen+0x83/0xa0 [ 30.032554] getname_kernel+0x24/0x370 [ 30.036429] kern_path_mountpoint+0x23/0x40 [ 30.040738] find_autofs_mount.isra.5+0x8c/0x2b0 [ 30.045479] ? autofs_dev_ioctl_protosubver+0x80/0x80 [ 30.050653] ? autofs_dev_ioctl_compat+0x30/0x30 [ 30.055397] ? check_same_owner+0x320/0x320 [ 30.059705] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 30.064709] ? __check_object_size+0x95/0x5d9 [ 30.069191] autofs_dev_ioctl_openmount+0x183/0x340 [ 30.074192] ? autofs_dev_ioctl_requester+0x5a0/0x5a0 [ 30.079365] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.084885] ? _copy_from_user+0xdf/0x150 [ 30.089018] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.094538] ? autofs_dev_ioctl_requester+0x5a0/0x5a0 [ 30.099717] _autofs_dev_ioctl+0x67a/0x890 [ 30.103937] ? autofs_dev_ioctl_closemount+0x90/0x90 [ 30.109023] ? trace_hardirqs_off+0xd/0x10 [ 30.113240] ? debug_check_no_obj_freed+0x2ff/0x584 [ 30.118240] ? _autofs_dev_ioctl+0x890/0x890 [ 30.122634] autofs_dev_ioctl+0x1b/0x30 [ 30.126597] do_vfs_ioctl+0x1cf/0x16a0 [ 30.130470] ? rcu_pm_notify+0xc0/0xc0 [ 30.134356] ? trace_hardirqs_off+0xd/0x10 [ 30.138592] ? ioctl_preallocate+0x2e0/0x2e0 [ 30.142983] ? fget_raw+0x20/0x20 [ 30.146419] ? kmem_cache_free+0x25c/0x2d0 [ 30.150649] ? putname+0xf7/0x130 [ 30.154086] ? do_sys_open+0x3c3/0x740 [ 30.157958] ? security_file_ioctl+0x94/0xc0 [ 30.162355] ksys_ioctl+0xa9/0xd0 [ 30.165790] __x64_sys_ioctl+0x73/0xb0 [ 30.169659] do_syscall_64+0x1b1/0x800 [ 30.173555] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 30.178382] ? syscall_return_slowpath+0x5c0/0x5c0 [ 30.183295] ? syscall_return_slowpath+0x30f/0x5c0 [ 30.188208] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 30.193552] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.198386] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.203554] RIP: 0033:0x43fd19 [ 30.206733] RSP: 002b:00007fffa5b980a8 EFLAGS: 00000213 ORIG_RAX: 0000000000000010 [ 30.214420] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd19 [ 30.221668] RDX: 0000000020000080 RSI: 8000000000009374 RDI: 0000000000000003 [ 30.228917] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 30.236164] R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401640 [ 30.243413] R13: 00000000004016d0 R14: 0000000000000000 R15: 0000000000000000 [ 30.250667] [ 30.252272] Allocated by task 4503: [ 30.256072] save_stack+0x43/0xd0 [ 30.259513] kasan_kmalloc+0xc4/0xe0 [ 30.263205] __kmalloc_track_caller+0x14a/0x760 [ 30.267854] memdup_user+0x2c/0xa0 [ 30.271374] _autofs_dev_ioctl+0x1a8/0x890 [ 30.275589] autofs_dev_ioctl+0x1b/0x30 [ 30.279544] do_vfs_ioctl+0x1cf/0x16a0 [ 30.283412] ksys_ioctl+0xa9/0xd0 [ 30.286844] __x64_sys_ioctl+0x73/0xb0 [ 30.290710] do_syscall_64+0x1b1/0x800 [ 30.294574] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.299733] [ 30.301336] Freed by task 2842: [ 30.304593] save_stack+0x43/0xd0 [ 30.308026] __kasan_slab_free+0x11a/0x170 [ 30.312237] kasan_slab_free+0xe/0x10 [ 30.316012] kfree+0xd9/0x260 [ 30.319094] single_release+0x8f/0xb0 [ 30.322870] __fput+0x34d/0x890 [ 30.326126] ____fput+0x15/0x20 [ 30.329382] task_work_run+0x1e4/0x290 [ 30.333246] exit_to_usermode_loop+0x2bd/0x310 [ 30.337814] do_syscall_64+0x6ac/0x800 [ 30.341679] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.346850] [ 30.348458] The buggy address belongs to the object at ffff8801d7039240 [ 30.348458] which belongs to the cache kmalloc-32 of size 32 [ 30.360930] The buggy address is located 24 bytes inside of [ 30.360930] 32-byte region [ffff8801d7039240, ffff8801d7039260) [ 30.372606] The buggy address belongs to the page: [ 30.377516] page:ffffea00075c0e40 count:1 mapcount:0 mapping:ffff8801d7039000 index:0xffff8801d7039fc1 [ 30.386940] flags: 0x2fffc0000000100(slab) [ 30.391154] raw: 02fffc0000000100 ffff8801d7039000 ffff8801d7039fc1 000000010000003f [ 30.399185] raw: ffffea00075c0c20 ffff8801da801248 ffff8801da8001c0 0000000000000000 [ 30.407042] page dumped because: kasan: bad access detected [ 30.412727] [ 30.414329] Memory state around the buggy address: [ 30.419235] ffff8801d7039100: 00 04 fc fc fc fc fc fc fb fb fb fb fc fc fc fc [ 30.426572] ffff8801d7039180: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc [ 30.433915] >ffff8801d7039200: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc [ 30.441250] ^ [ 30.447458] ffff8801d7039280: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc [ 30.454805] ffff8801d7039300: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc [ 30.462136] ================================================================== [ 30.469468] Disabling lock debugging due to kernel taint [ 30.475058] Kernel panic - not syncing: panic_on_warn set ... [ 30.475058] [ 30.482404] CPU: 0 PID: 4503 Comm: syz-executor745 Tainted: G B 4.17.0-rc7+ #78 [ 30.491128] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.500458] Call Trace: [ 30.503032] dump_stack+0x1b9/0x294 [ 30.506641] ? dump_stack_print_info.cold.2+0x52/0x52 [ 30.511811] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 30.516559] ? strlen+0x40/0xa0 [ 30.519823] panic+0x22f/0x4de [ 30.522991] ? add_taint.cold.5+0x16/0x16 [ 30.527124] ? do_raw_spin_unlock+0x9e/0x2e0 [ 30.531511] ? do_raw_spin_unlock+0x9e/0x2e0 [ 30.535900] ? strlen+0x83/0xa0 [ 30.539158] kasan_end_report+0x47/0x4f [ 30.543110] kasan_report.cold.7+0x76/0x2fe [ 30.547410] __asan_report_load1_noabort+0x14/0x20 [ 30.552315] strlen+0x83/0xa0 [ 30.555396] getname_kernel+0x24/0x370 [ 30.559257] kern_path_mountpoint+0x23/0x40 [ 30.563557] find_autofs_mount.isra.5+0x8c/0x2b0 [ 30.568291] ? autofs_dev_ioctl_protosubver+0x80/0x80 [ 30.573471] ? autofs_dev_ioctl_compat+0x30/0x30 [ 30.578204] ? check_same_owner+0x320/0x320 [ 30.582512] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 30.587512] ? __check_object_size+0x95/0x5d9 [ 30.591987] autofs_dev_ioctl_openmount+0x183/0x340 [ 30.596979] ? autofs_dev_ioctl_requester+0x5a0/0x5a0 [ 30.602145] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.607659] ? _copy_from_user+0xdf/0x150 [ 30.611785] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.617296] ? autofs_dev_ioctl_requester+0x5a0/0x5a0 [ 30.622463] _autofs_dev_ioctl+0x67a/0x890 [ 30.626674] ? autofs_dev_ioctl_closemount+0x90/0x90 [ 30.631751] ? trace_hardirqs_off+0xd/0x10 [ 30.635962] ? debug_check_no_obj_freed+0x2ff/0x584 [ 30.640966] ? _autofs_dev_ioctl+0x890/0x890 [ 30.645359] autofs_dev_ioctl+0x1b/0x30 [ 30.649310] do_vfs_ioctl+0x1cf/0x16a0 [ 30.653177] ? rcu_pm_notify+0xc0/0xc0 [ 30.657038] ? trace_hardirqs_off+0xd/0x10 [ 30.661249] ? ioctl_preallocate+0x2e0/0x2e0 [ 30.665645] ? fget_raw+0x20/0x20 [ 30.669076] ? kmem_cache_free+0x25c/0x2d0 [ 30.673294] ? putname+0xf7/0x130 [ 30.676726] ? do_sys_open+0x3c3/0x740 [ 30.680595] ? security_file_ioctl+0x94/0xc0 [ 30.684981] ksys_ioctl+0xa9/0xd0 [ 30.688411] __x64_sys_ioctl+0x73/0xb0 [ 30.692283] do_syscall_64+0x1b1/0x800 [ 30.696145] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 30.700971] ? syscall_return_slowpath+0x5c0/0x5c0 [ 30.705875] ? syscall_return_slowpath+0x30f/0x5c0 [ 30.710782] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 30.716131] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.720949] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.726116] RIP: 0033:0x43fd19 [ 30.729281] RSP: 002b:00007fffa5b980a8 EFLAGS: 00000213 ORIG_RAX: 0000000000000010 [ 30.736975] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd19 [ 30.744232] RDX: 0000000020000080 RSI: 8000000000009374 RDI: 0000000000000003 [ 30.751478] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 30.758722] R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401640 [ 30.765974] R13: 00000000004016d0 R14: 0000000000000000 R15: 0000000000000000 [ 30.773706] Dumping ftrace buffer: [ 30.777219] (ftrace buffer empty) [ 30.780904] Kernel Offset: disabled [ 30.784507] Rebooting in 86400 seconds..