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-0,10.128.0.38' (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: [   43.455829] ------------[ cut here ]------------
[   43.456646] WARNING: CPU: 0 PID: 2991 at drivers/net/tun.c:1744 tun_get_user+0x2de3/0x36d0
[   43.457837] Kernel panic - not syncing: panic_on_warn set ...
[   43.457837] 
[   43.458846] CPU: 0 PID: 2991 Comm: syzkaller789715 Not tainted 4.14.0-rc5-next-20171018+ #36
[   43.459966] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   43.461183] Call Trace:
[   43.461541]  dump_stack+0x194/0x257
[   43.462036]  ? arch_local_irq_restore+0x53/0x53
[   43.462665]  ? vsnprintf+0x1ed/0x1900
[   43.463181]  panic+0x1e4/0x41c
[   43.463616]  ? refcount_error_report+0x214/0x214
[   43.464249]  ? show_regs_print_info+0x65/0x65
[   43.464857]  ? __warn+0x1a9/0x1e0
[   43.465328]  ? tun_get_user+0x2de3/0x36d0
[   43.465883]  __warn+0x1c4/0x1e0
[   43.466328]  ? tun_get_user+0x2de3/0x36d0
[   43.466887]  report_bug+0x211/0x2d0
[   43.467385]  fixup_bug+0x40/0x90
[   43.467859]  do_trap+0x260/0x390
[   43.468321]  do_error_trap+0x120/0x390
[   43.468847]  ? kfree_skbmem+0xe2/0x1d0
[   43.469373]  ? do_trap+0x390/0x390
[   43.469849]  ? __mutex_unlock_slowpath+0xe9/0xac0
[   43.470493]  ? tun_get_user+0x2de3/0x36d0
[   43.471051]  ? wait_for_completion+0x770/0x770
[   43.471669]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   43.472319]  do_invalid_op+0x1b/0x20
[   43.472820]  invalid_op+0x18/0x20
[   43.473286] RIP: 0010:tun_get_user+0x2de3/0x36d0
[   43.473917] RSP: 0018:ffff8801d21ef730 EFLAGS: 00010286
[   43.474628] RAX: dffffc0000000000 RBX: ffff8801d1db9658 RCX: dffffc0000000000
[   43.475580] RDX: ffffffff87024140 RSI: 0000000000000000 RDI: 0000000000000282
[   43.476533] RBP: ffff8801d21efae0 R08: 0000000000000001 R09: 0000000000000000
[   43.483771] R10: ffffffff870692e0 R11: 0000000000000000 R12: ffff8801c16c7500
[   43.491006] R13: ffff8801d1db96c8 R14: 0000000000000000 R15: ffff8801d1cf0d40
[   43.498283]  ? tun_build_skb.isra.48+0x16e0/0x16e0
[   43.503177]  ? kmem_cache_alloc+0x12e/0x760
[   43.507466]  ? do_mmap+0x69b/0xd40
[   43.510972]  ? vm_mmap_pgoff+0x1de/0x280
[   43.514999]  ? SyS_mmap+0x16/0x20
[   43.518416]  ? entry_SYSCALL_64_fastpath+0x1f/0xbe
[   43.523316]  ? avc_has_extended_perms+0x12c0/0x12c0
[   43.528300]  ? check_noncircular+0x20/0x20
[   43.532514]  ? tun_get+0x1ab/0x2e0
[   43.536026]  ? lock_release+0xa40/0xa40
[   43.539970]  ? __lock_is_held+0xb6/0x140
[   43.544009]  ? tun_get+0x1d4/0x2e0
[   43.547515]  ? tun_chr_close+0x60/0x60
[   43.551369]  ? __check_object_size+0x25d/0x4f0
[   43.555919]  ? rcu_note_context_switch+0x710/0x710
[   43.560820]  tun_chr_write_iter+0xb9/0x160
[   43.565023]  do_iter_readv_writev+0x525/0x7f0
[   43.569491]  ? vfs_dedupe_file_range+0x8f0/0x8f0
[   43.574220]  ? rw_verify_area+0xe5/0x2b0
[   43.578252]  do_iter_write+0x154/0x540
[   43.582108]  ? dup_iter+0x260/0x260
[   43.585726]  vfs_writev+0x18a/0x340
[   43.589320]  ? __fget_light+0x297/0x380
[   43.593267]  ? vfs_iter_write+0xb0/0xb0
[   43.597212]  ? up_read+0x1a/0x40
[   43.600551]  ? __do_page_fault+0x3d6/0xd60
[   43.604754]  ? security_mmap_file+0x143/0x180
[   43.609224]  ? mm_fault_error+0x2c0/0x2c0
[   43.613345]  ? __fdget_pos+0x130/0x190
[   43.617200]  ? __fdget_raw+0x20/0x20
[   43.620884]  ? __do_page_fault+0xd60/0xd60
[   43.625088]  do_writev+0xfc/0x2a0
[   43.628506]  ? do_writev+0xfc/0x2a0
[   43.632105]  ? vfs_writev+0x340/0x340
[   43.635871]  ? entry_SYSCALL_64_fastpath+0x5/0xbe
[   43.640682]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   43.645671]  SyS_writev+0x27/0x30
[   43.649093]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   43.653815] RIP: 0033:0x4449a0
[   43.656972] RSP: 002b:00007ffc616a3778 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
[   43.664646] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004449a0
[   43.671882] RDX: 0000000000000002 RSI: 00007ffc616a3780 RDI: 0000000000000003
[   43.679117] RBP: 0000000000000082 R08: 0000000000000011 R09: 0000000000000004
[   43.686352] R10: 0000000068f78f4d R11: 0000000000000246 R12: 00000000004020b0
[   43.693590] R13: 0000000000402140 R14: 0000000000000000 R15: 0000000000000000
[   43.700973] Dumping ftrace buffer:
[   43.704520]    (ftrace buffer empty)
[   43.708202] Kernel Offset: disabled
[   43.711801] Rebooting in 86400 seconds..