INIT: Entering runlevel: 2

[info] Using makefile-style concurrent boot in runlevel 2.
[....] 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.

Debian GNU/Linux 7 syzkaller ttyS0

Warning: Permanently added 'ci-upstream-mmots-kasan-gce-5,10.128.0.50' (ECDSA) to the list of known hosts.
net.ipv6.conf.syz0.accept_dad = 0
net.ipv6.conf.syz0.router_solicitations = 0
executing program
syzkaller login: [   34.170134] ------------[ cut here ]------------
[   34.175547] WARNING: CPU: 0 PID: 2979 at drivers/net/tun.c:1744 tun_get_user+0x2de3/0x36d0
[   34.184224] Kernel panic - not syncing: panic_on_warn set ...
[   34.184224] 
[   34.191563] CPU: 0 PID: 2979 Comm: syzkaller282635 Not tainted 4.14.0-rc4-mm1+ #16
[   34.199241] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   34.208571] Call Trace:
[   34.211137]  dump_stack+0x194/0x257
[   34.214744]  ? arch_local_irq_restore+0x53/0x53
[   34.219400]  panic+0x1e4/0x41c
[   34.222571]  ? refcount_error_report+0x214/0x214
[   34.227299]  ? show_regs_print_info+0x65/0x65
[   34.231783]  ? tun_get_user+0x2de3/0x36d0
[   34.235905]  __warn+0x1c4/0x1e0
[   34.239157]  ? tun_get_user+0x2de3/0x36d0
[   34.243283]  report_bug+0x211/0x2d0
[   34.246891]  fixup_bug+0x40/0x90
[   34.250230]  do_trap+0x260/0x390
[   34.253576]  do_error_trap+0x120/0x390
[   34.257447]  ? kfree_skbmem+0xe2/0x1d0
[   34.261314]  ? do_trap+0x390/0x390
[   34.264826]  ? __mutex_unlock_slowpath+0xe9/0xac0
[   34.269641]  ? tun_get_user+0x2de3/0x36d0
[   34.273766]  ? wait_for_completion+0x7b0/0x7b0
[   34.278325]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   34.283145]  do_invalid_op+0x1b/0x20
[   34.286833]  invalid_op+0x18/0x20
[   34.290259] RIP: 0010:tun_get_user+0x2de3/0x36d0
[   34.294985] RSP: 0018:ffff8801ce03f730 EFLAGS: 00010286
[   34.300323] RAX: dffffc0000000000 RBX: ffff8801ceb645d8 RCX: dffffc0000000000
[   34.307565] RDX: ffffffff86e2ace0 RSI: 0000000000000000 RDI: ffffed0039c07ea8
[   34.315068] RBP: ffff8801ce03fae0 R08: 0000000000000080 R09: 0000000000000000
[   34.322306] R10: ffffffff86e71a60 R11: 0000000000000000 R12: ffff8801cd7418c0
[   34.329546] R13: ffff8801ceb64648 R14: 0000000000000000 R15: ffff8801ce170dc0
[   34.336828]  ? tun_build_skb.isra.48+0x16e0/0x16e0
[   34.341732]  ? do_mmap+0x6a1/0xd50
[   34.345272]  ? tun_chr_close+0x60/0x60
[   34.349138]  ? lock_release+0xd70/0xd70
[   34.353088]  ? __lock_is_held+0xbc/0x140
[   34.357133]  ? tun_get+0x1d4/0x2e0
[   34.360645]  ? tun_chr_close+0x60/0x60
[   34.364504]  ? __check_object_size+0x25d/0x4f0
[   34.369065]  tun_chr_write_iter+0xbf/0x160
[   34.373273]  do_iter_readv_writev+0x531/0x7f0
[   34.377745]  ? vfs_dedupe_file_range+0x900/0x900
[   34.382477]  ? rw_verify_area+0xe5/0x2b0
[   34.386511]  do_iter_write+0x15a/0x540
[   34.390370]  ? dup_iter+0x260/0x260
[   34.393977]  vfs_writev+0x18a/0x340
[   34.397577]  ? __fget_light+0x29d/0x390
[   34.401528]  ? vfs_iter_write+0xb0/0xb0
[   34.405476]  ? up_read+0x1a/0x40
[   34.408823]  ? __do_page_fault+0x3d6/0xd60
[   34.413029]  ? security_mmap_file+0x143/0x180
[   34.417505]  ? mm_fault_error+0x2c0/0x2c0
[   34.421635]  ? __fdget_pos+0x136/0x1a0
[   34.425496]  ? __fdget_raw+0x20/0x20
[   34.429187]  ? __do_page_fault+0xd60/0xd60
[   34.433400]  do_writev+0xfc/0x2a0
[   34.436829]  ? do_writev+0xfc/0x2a0
[   34.440438]  ? vfs_writev+0x340/0x340
[   34.444211]  ? entry_SYSCALL_64_fastpath+0x5/0xbe
[   34.449028]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   34.454029]  SyS_writev+0x27/0x30
[   34.457456]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   34.462185] RIP: 0033:0x444b10
[   34.465348] RSP: 002b:00007ffde0023708 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
[   34.473030] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000444b10
[   34.480273] RDX: 0000000000000002 RSI: 00007ffde0023710 RDI: 0000000000000003
[   34.487518] RBP: 0000000000000082 R08: 000000000000003e R09: 0000000000000004
[   34.494761] R10: 00000000aaaaaaaa R11: 0000000000000246 R12: 0000000000402220
[   34.502001] R13: 00000000004022b0 R14: 0000000000000000 R15: 0000000000000000
[   34.509440] Dumping ftrace buffer:
[   34.513023]    (ftrace buffer empty)
[   34.516709] Kernel Offset: disabled
[   34.520321] Rebooting in 86400 seconds..