[ OK ] Started Getty on tty3. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty2. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.21' (ECDSA) to the list of known hosts. syzkaller login: [ 27.648629] IPVS: ftp: loaded support on port[0] = 21 executing program [ 27.748289] F2FS-fs (loop0): Invalid blocksize (65536), supports only 4KB [ 27.748289] [ 27.756789] F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock [ 27.765628] F2FS-fs (loop0): invalid crc value [ 27.813283] F2FS-fs (loop0): Mounted with checkpoint version = 3e17dab0 [ 27.962393] [ 27.964019] ================================================ [ 27.969788] WARNING: lock held when returning to user space! [ 27.975564] 4.14.296-syzkaller #0 Not tainted [ 27.980030] ------------------------------------------------ [ 27.985800] syz-executor198/7982 is leaving the kernel with locks still held! [ 27.993043] 1 lock held by syz-executor198/7982: [ 27.997767] #0: (sb_writers#10){.+.+}, at: [] mnt_want_write_file+0xfd/0x3b0 [ 28.008256] ------------[ cut here ]------------ [ 28.013018] WARNING: CPU: 0 PID: 7982 at fs/namespace.c:1178 cleanup_mnt+0x222/0x2c0 [ 28.020873] Kernel panic - not syncing: panic_on_warn set ... [ 28.020873] [ 28.028208] CPU: 0 PID: 7982 Comm: syz-executor198 Not tainted 4.14.296-syzkaller #0 [ 28.036083] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 [ 28.045497] Call Trace: [ 28.048062] dump_stack+0x1b2/0x281 [ 28.051669] panic+0x1f9/0x42d [ 28.054839] ? add_taint.cold+0x16/0x16 [ 28.058787] ? cleanup_mnt+0x222/0x2c0 [ 28.062648] ? cleanup_mnt+0x222/0x2c0 [ 28.066515] __warn.cold+0x20/0x44 [ 28.070030] ? ist_end_non_atomic+0x10/0x10 [ 28.074324] ? cleanup_mnt+0x222/0x2c0 [ 28.078200] report_bug+0x208/0x250 [ 28.081821] do_error_trap+0x195/0x2d0 [ 28.085694] ? math_error+0x2d0/0x2d0 [ 28.089476] ? do_raw_spin_unlock+0x164/0x220 [ 28.093950] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 28.099229] ? trace_hardirqs_on+0x10/0x10 [ 28.103444] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 28.108266] invalid_op+0x1b/0x40 [ 28.111703] RIP: 0010:cleanup_mnt+0x222/0x2c0 [ 28.116177] RSP: 0018:ffff8880b4b17d08 EFLAGS: 00010297 [ 28.121518] RAX: ffff8880b335a380 RBX: dffffc0000000000 RCX: 0000000000000002 [ 28.128761] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8a0932e0 [ 28.136019] RBP: 0000000000000008 R08: 0000000000000001 R09: 0000000000000000 [ 28.143269] R10: 0000000000000000 R11: ffff8880b335a380 R12: ffff8880b3a2ea00 [ 28.150525] R13: 0000000000000001 R14: 0000000000000007 R15: fffffbfff1412696 [ 28.157785] ? cleanup_mnt+0x222/0x2c0 [ 28.161655] task_work_run+0x11f/0x190 [ 28.165526] do_exit+0xa44/0x2850 [ 28.168966] ? mm_update_next_owner+0x5b0/0x5b0 [ 28.173612] ? lock_downgrade+0x740/0x740 [ 28.177733] do_group_exit+0x100/0x2e0 [ 28.181599] SyS_exit_group+0x19/0x20 [ 28.185372] ? do_group_exit+0x2e0/0x2e0 [ 28.189417] do_syscall_64+0x1d5/0x640 [ 28.193286] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 28.198450] RIP: 0033:0x7f3d90052c89 [ 28.202138] RSP: 002b:00007fff68583ad8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 28.209824] RAX: ffffffffffffffda RBX: 00007f3d900c9330 RCX: 00007f3d90052c89 [ 28.217070] RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001 [ 28.224313] RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 00007f3d900c3e40 [ 28.231557] R10: 00007f3d900c3e40 R11: 0000000000000246 R12: 00007f3d900c9330 [ 28.238800] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 [ 28.246125] Kernel Offset: disabled [ 28.249737] Rebooting in 86400 seconds..