[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 28.523340] kauditd_printk_skb: 7 callbacks suppressed [ 28.523353] audit: type=1800 audit(1543143875.948:29): pid=5850 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 28.548589] audit: type=1800 audit(1543143875.948:30): pid=5850 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.117' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 35.605954] ================================================================== [ 35.613405] BUG: KASAN: slab-out-of-bounds in queue_stack_map_push_elem+0x185/0x290 [ 35.621218] Write of size 262146 at addr ffff8881bf9b7b88 by task syz-executor254/6005 [ 35.629396] [ 35.631015] CPU: 1 PID: 6005 Comm: syz-executor254 Not tainted 4.20.0-rc3+ #313 [ 35.638444] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 35.647781] Call Trace: [ 35.650352] dump_stack+0x244/0x39d [ 35.653964] ? dump_stack_print_info.cold.1+0x20/0x20 [ 35.659136] ? printk+0xa7/0xcf [ 35.662400] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 35.667143] print_address_description.cold.7+0x9/0x1ff [ 35.672491] kasan_report.cold.8+0x242/0x309 [ 35.676886] ? queue_stack_map_push_elem+0x185/0x290 [ 35.681976] check_memory_region+0x13e/0x1b0 [ 35.686380] memcpy+0x37/0x50 [ 35.689470] queue_stack_map_push_elem+0x185/0x290 [ 35.694382] ? queue_map_pop_elem+0x30/0x30 [ 35.698687] map_update_elem+0x605/0xf60 [ 35.702736] __x64_sys_bpf+0x32d/0x520 [ 35.706608] ? bpf_prog_get+0x20/0x20 [ 35.710405] do_syscall_64+0x1b9/0x820 [ 35.714276] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 35.719627] ? syscall_return_slowpath+0x5e0/0x5e0 [ 35.724539] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 35.729367] ? trace_hardirqs_on_caller+0x310/0x310 [ 35.734370] ? prepare_exit_to_usermode+0x291/0x3b0 [ 35.739375] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 35.744205] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 35.749376] RIP: 0033:0x4400e9 [ 35.752552] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 35.771434] RSP: 002b:00007fff816ba4b8 EFLAGS: 00000213 ORIG_RAX: 0000000000000141 [ 35.779126] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400e9 [ 35.786378] RDX: 0000000000000020 RSI: 0000000020000040 RDI: 0000000000000002 [ 35.793629] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 35.800880] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401970 [ 35.808131] R13: 0000000000401a00 R14: 0000000000000000 R15: 0000000000000000 [ 35.815389] [ 35.817001] Allocated by task 6005: [ 35.820617] save_stack+0x43/0xd0 [ 35.824050] kasan_kmalloc+0xc7/0xe0 [ 35.827746] __kmalloc_node+0x50/0x70 [ 35.831530] bpf_map_area_alloc+0x3f/0x90 [ 35.835658] queue_stack_map_alloc+0x192/0x290 [ 35.840219] map_create+0x3bd/0x1110 [ 35.843912] __x64_sys_bpf+0x303/0x520 [ 35.847783] do_syscall_64+0x1b9/0x820 [ 35.851654] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 35.856816] [ 35.858424] Freed by task 3717: [ 35.861685] save_stack+0x43/0xd0 [ 35.865119] __kasan_slab_free+0x102/0x150 [ 35.869338] kasan_slab_free+0xe/0x10 [ 35.873121] kfree+0xcf/0x230 [ 35.876207] kernfs_fop_release+0x12b/0x1a0 [ 35.880514] __fput+0x385/0xa30 [ 35.883774] ____fput+0x15/0x20 [ 35.887034] task_work_run+0x1e8/0x2a0 [ 35.890905] exit_to_usermode_loop+0x318/0x380 [ 35.895470] do_syscall_64+0x6be/0x820 [ 35.899342] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 35.904510] [ 35.906123] The buggy address belongs to the object at ffff8881bf9b7a40 [ 35.906123] which belongs to the cache kmalloc-512 of size 512 [ 35.918762] The buggy address is located 328 bytes inside of [ 35.918762] 512-byte region [ffff8881bf9b7a40, ffff8881bf9b7c40) [ 35.930616] The buggy address belongs to the page: [ 35.935542] page:ffffea0006fe6dc0 count:1 mapcount:0 mapping:ffff8881da800940 index:0xffff8881bf9b72c0 [ 35.944970] flags: 0x2fffc0000000200(slab) [ 35.949196] raw: 02fffc0000000200 ffffea0006fe6d08 ffffea0006f12148 ffff8881da800940 [ 35.957064] raw: ffff8881bf9b72c0 ffff8881bf9b7040 0000000100000003 0000000000000000 [ 35.964922] page dumped because: kasan: bad access detected [ 35.970607] [ 35.972216] Memory state around the buggy address: [ 35.977126] ffff8881bf9b7a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 35.984466] ffff8881bf9b7b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 35.991823] >ffff8881bf9b7b80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 35.999160] ^ [ 36.004588] ffff8881bf9b7c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 36.011927] ffff8881bf9b7c80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 36.019264] ================================================================== [ 36.026614] Disabling lock debugging due to kernel taint [ 36.032042] Kernel panic - not syncing: panic_on_warn set ... [ 36.037908] CPU: 1 PID: 6005 Comm: syz-executor254 Tainted: G B 4.20.0-rc3+ #313 [ 36.046719] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.056055] Call Trace: [ 36.058628] dump_stack+0x244/0x39d [ 36.062250] ? dump_stack_print_info.cold.1+0x20/0x20 [ 36.067440] panic+0x2ad/0x55c [ 36.070618] ? add_taint.cold.5+0x16/0x16 [ 36.074750] ? add_taint.cold.5+0x5/0x16 [ 36.078794] ? trace_hardirqs_off+0xaf/0x310 [ 36.083186] kasan_end_report+0x47/0x4f [ 36.087142] kasan_report.cold.8+0x76/0x309 [ 36.091445] ? queue_stack_map_push_elem+0x185/0x290 [ 36.096536] check_memory_region+0x13e/0x1b0 [ 36.100929] memcpy+0x37/0x50 [ 36.104032] queue_stack_map_push_elem+0x185/0x290 [ 36.108944] ? queue_map_pop_elem+0x30/0x30 [ 36.113246] map_update_elem+0x605/0xf60 [ 36.117289] __x64_sys_bpf+0x32d/0x520 [ 36.121157] ? bpf_prog_get+0x20/0x20 [ 36.124948] do_syscall_64+0x1b9/0x820 [ 36.128816] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 36.134160] ? syscall_return_slowpath+0x5e0/0x5e0 [ 36.139074] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 36.143900] ? trace_hardirqs_on_caller+0x310/0x310 [ 36.148899] ? prepare_exit_to_usermode+0x291/0x3b0 [ 36.153901] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 36.158726] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.163897] RIP: 0033:0x4400e9 [ 36.167073] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 36.185953] RSP: 002b:00007fff816ba4b8 EFLAGS: 00000213 ORIG_RAX: 0000000000000141 [ 36.193662] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400e9 [ 36.200912] RDX: 0000000000000020 RSI: 0000000020000040 RDI: 0000000000000002 [ 36.208165] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 36.215442] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401970 [ 36.222706] R13: 0000000000401a00 R14: 0000000000000000 R15: 0000000000000000 [ 36.230916] Kernel Offset: disabled [ 36.234536] Rebooting in 86400 seconds..