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-next-kasan-gce-8,10.128.0.48' (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: [   55.783308] ------------[ cut here ]------------
[   55.788219] WARNING: CPU: 1 PID: 2982 at drivers/net/tun.c:1744 tun_get_user+0x2de3/0x36d0
[   55.796773] Kernel panic - not syncing: panic_on_warn set ...
[   55.796773] 
[   55.804110] CPU: 1 PID: 2982 Comm: syzkaller089313 Not tainted 4.14.0-rc4-next-20171009+ #33
[   55.812653] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   55.821980] Call Trace:
[   55.824542]  dump_stack+0x194/0x257
[   55.828143]  ? arch_local_irq_restore+0x53/0x53
[   55.832794]  panic+0x1e4/0x41c
[   55.835958]  ? refcount_error_report+0x214/0x214
[   55.840687]  ? show_regs_print_info+0x65/0x65
[   55.845170]  ? tun_get_user+0x2de3/0x36d0
[   55.849289]  __warn+0x1c4/0x1e0
[   55.852541]  ? tun_get_user+0x2de3/0x36d0
[   55.856666]  report_bug+0x211/0x2d0
[   55.860270]  fixup_bug+0x40/0x90
[   55.863606]  do_trap+0x260/0x390
[   55.866948]  do_error_trap+0x120/0x390
[   55.870806]  ? kfree_skbmem+0xe2/0x1d0
[   55.874667]  ? do_trap+0x390/0x390
[   55.878177]  ? __mutex_unlock_slowpath+0xe9/0xac0
[   55.882989]  ? tun_get_user+0x2de3/0x36d0
[   55.887109]  ? wait_for_completion+0x7b0/0x7b0
[   55.891671]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   55.896490]  do_invalid_op+0x1b/0x20
[   55.900173]  invalid_op+0x18/0x20
[   55.903597] RIP: 0010:tun_get_user+0x2de3/0x36d0
[   55.908319] RSP: 0018:ffff8801ce747730 EFLAGS: 00010286
[   55.913663] RAX: dffffc0000000000 RBX: ffff8801ce0beed8 RCX: dffffc0000000000
[   55.920902] RDX: ffffffff86e2ace0 RSI: 0000000000000000 RDI: ffffed0039ce8ea8
[   55.928180] RBP: ffff8801ce747ae0 R08: 0000000000000080 R09: 0000000000000000
[   55.935420] R10: ffffffff86e71a60 R11: 0000000000000000 R12: ffff8801ce062a80
[   55.942662] R13: ffff8801ce0bef48 R14: 0000000000000000 R15: ffff8801ce108dc0
[   55.949944]  ? tun_build_skb.isra.48+0x16e0/0x16e0
[   55.954845]  ? do_mmap+0x6a1/0xd50
[   55.958383]  ? tun_chr_close+0x60/0x60
[   55.962246]  ? lock_release+0xd70/0xd70
[   55.966194]  ? __lock_is_held+0xbc/0x140
[   55.970236]  ? tun_get+0x1d4/0x2e0
[   55.973748]  ? tun_chr_close+0x60/0x60
[   55.977608]  ? __check_object_size+0x25d/0x4f0
[   55.982169]  tun_chr_write_iter+0xbf/0x160
[   55.986379]  do_iter_readv_writev+0x531/0x7f0
[   55.990854]  ? vfs_dedupe_file_range+0x900/0x900
[   55.995588]  ? rw_verify_area+0xe5/0x2b0
[   55.999624]  do_iter_write+0x15a/0x540
[   56.003484]  ? dup_iter+0x260/0x260
[   56.007090]  vfs_writev+0x18a/0x340
[   56.010689]  ? __fget_light+0x29d/0x390
[   56.014635]  ? vfs_iter_write+0xb0/0xb0
[   56.018589]  ? up_read+0x1a/0x40
[   56.021927]  ? __do_page_fault+0x3d6/0xd60
[   56.026132]  ? security_mmap_file+0x143/0x180
[   56.030606]  ? mm_fault_error+0x2c0/0x2c0
[   56.034731]  ? __fdget_pos+0x136/0x1a0
[   56.038590]  ? __fdget_raw+0x20/0x20
[   56.042278]  ? __do_page_fault+0xd60/0xd60
[   56.046492]  do_writev+0xfc/0x2a0
[   56.049922]  ? do_writev+0xfc/0x2a0
[   56.053524]  ? vfs_writev+0x340/0x340
[   56.057297]  ? entry_SYSCALL_64_fastpath+0x5/0xbe
[   56.062113]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   56.067104]  SyS_writev+0x27/0x30
[   56.070529]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   56.075255] RIP: 0033:0x444b10
[   56.078417] RSP: 002b:00007fff039079b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
[   56.086098] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000444b10
[   56.093339] RDX: 0000000000000002 RSI: 00007fff039079c0 RDI: 0000000000000003
[   56.100580] RBP: 0000000000000082 R08: 000000000000003e R09: 0000000000000004
[   56.107820] R10: 00000000aaaaaaaa R11: 0000000000000246 R12: 0000000000402220
[   56.115058] R13: 00000000004022b0 R14: 0000000000000000 R15: 0000000000000000
[   56.122789] Dumping ftrace buffer:
[   56.126350]    (ftrace buffer empty)
[   56.130031] Kernel Offset: disabled
[   56.133639] Rebooting in 86400 seconds..