[....] 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. [ 28.952565] kauditd_printk_skb: 7 callbacks suppressed [ 28.952579] audit: type=1800 audit(1543870752.813:29): pid=5891 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 [ 28.983623] audit: type=1800 audit(1543870752.823:30): pid=5891 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 syzkaller login: [ 31.060011] sshd (6030) used greatest stack depth: 15744 bytes left Warning: Permanently added '10.128.0.2' (ECDSA) to the list of known hosts. executing program [ 37.690883] [ 37.692589] ==================================== [ 37.697330] WARNING: syz-executor797/6047 still has locks held! [ 37.703417] 4.20.0-rc5+ #361 Not tainted [ 37.707471] ------------------------------------ [ 37.712253] 1 lock held by syz-executor797/6047: [ 37.717013] #0: 00000000280703f3 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x53/0x120 [ 37.726294] [ 37.726294] stack backtrace: [ 37.730896] CPU: 0 PID: 6047 Comm: syz-executor797 Not tainted 4.20.0-rc5+ #361 [ 37.738328] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.747660] Call Trace: [ 37.750232] dump_stack+0x244/0x39d [ 37.753842] ? dump_stack_print_info.cold.1+0x20/0x20 [ 37.759029] ? vprintk_func+0x85/0x181 [ 37.762916] debug_check_no_locks_held.cold.49+0x93/0x9f [ 37.768348] flush_old_exec+0x1ea2/0x2480 [ 37.772481] ? save_stack+0x43/0xd0 [ 37.776089] ? __kmalloc+0x15b/0x760 [ 37.779789] ? copy_strings_kernel+0x110/0x110 [ 37.784371] ? iov_iter_init+0xe5/0x210 [ 37.788341] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 37.793861] ? __vfs_read+0x11f/0x9b0 [ 37.797644] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.803166] ? fsnotify+0x50e/0xef0 [ 37.806773] ? fsnotify+0xef0/0xef0 [ 37.810382] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.815901] ? fsnotify_first_mark+0x350/0x350 [ 37.820473] ? __fsnotify_parent+0xcc/0x430 [ 37.824779] ? fsnotify+0xef0/0xef0 [ 37.828389] ? rw_verify_area+0x118/0x360 [ 37.832527] ? vfs_read+0x1ce/0x3c0 [ 37.836153] ? kernel_read+0xab/0x120 [ 37.839977] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 37.845008] ? load_elf_phdrs+0x1e4/0x270 [ 37.849137] ? writenote+0x3d0/0x3d0 [ 37.852832] ? __kasan_slab_free+0x119/0x150 [ 37.857224] load_elf_binary+0xa9a/0x5cf0 [ 37.861354] ? find_held_lock+0x36/0x1c0 [ 37.865403] ? notesize.isra.6+0x80/0x80 [ 37.869444] ? ima_file_mmap+0x160/0x160 [ 37.873488] ? lock_downgrade+0x900/0x900 [ 37.877620] ? kasan_check_write+0x14/0x20 [ 37.881839] search_binary_handler+0x17d/0x570 [ 37.886423] __do_execve_file.isra.33+0x1661/0x25d0 [ 37.891424] ? prepare_bprm_creds+0x120/0x120 [ 37.895904] ? usercopy_warn+0x110/0x110 [ 37.899952] ? check_preemption_disabled+0x48/0x280 [ 37.904960] ? rcu_lockdep_current_cpu_online+0x1a4/0x210 [ 37.910496] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 37.916051] ? strncpy_from_user+0x411/0x5a0 [ 37.920455] ? digsig_verify+0x1530/0x1530 [ 37.924674] ? kmem_cache_alloc+0x33a/0x730 [ 37.928977] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 37.933545] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.939075] __x64_sys_execveat+0xed/0x130 [ 37.943298] do_syscall_64+0x1b9/0x820 [ 37.947182] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 37.952543] ? syscall_return_slowpath+0x5e0/0x5e0 [ 37.957460] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 37.962292] ? trace_hardirqs_on_caller+0x310/0x310 [ 37.967291] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 37.972290] ? prepare_exit_to_usermode+0x291/0x3b0 [ 37.977291] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 37.982117] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 37.987312] RIP: 0033:0x445789 [ 37.990517] Code: e8 6c b6 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 38.009415] RSP: 002b:00007f560ea8cdb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000142 [ 38.017147] RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 0000000000445789 [ 38.024429] RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 [ 38.031681] RBP: 00000000006dac20 R08: 0000000000001000 R09: 0000000000000000 [ 38.038930] R10: 0000000000000000 R11: