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-2,10.128.0.10' (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: [   36.754476] ------------[ cut here ]------------
[   36.755486] WARNING: CPU: 0 PID: 2993 at drivers/net/tun.c:1744 tun_get_user+0x2de3/0x36d0
[   36.757117] Kernel panic - not syncing: panic_on_warn set ...
[   36.757117] 
[   36.758148] CPU: 0 PID: 2993 Comm: syzkaller849951 Not tainted 4.14.0-rc5-mm1+ #20
[   36.759156] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   36.760373] Call Trace:
[   36.760736]  dump_stack+0x194/0x257
[   36.761229]  ? arch_local_irq_restore+0x53/0x53
[   36.761858]  ? vsnprintf+0x1ed/0x1900
[   36.762377]  panic+0x1e4/0x41c
[   36.762812]  ? refcount_error_report+0x214/0x214
[   36.763463]  ? show_regs_print_info+0x65/0x65
[   36.764070]  ? __warn+0x1a9/0x1e0
[   36.764542]  ? tun_get_user+0x2de3/0x36d0
[   36.765098]  __warn+0x1c4/0x1e0
[   36.765545]  ? tun_get_user+0x2de3/0x36d0
[   36.766127]  report_bug+0x211/0x2d0
[   36.766623]  fixup_bug+0x40/0x90
[   36.767079]  do_trap+0x260/0x390
[   36.767542]  do_error_trap+0x120/0x390
[   36.768064]  ? kfree_skbmem+0xe2/0x1d0
[   36.768606]  ? do_trap+0x390/0x390
[   36.769083]  ? __mutex_unlock_slowpath+0xe9/0xac0
[   36.769732]  ? tun_get_user+0x2de3/0x36d0
[   36.770357]  ? wait_for_completion+0x770/0x770
[   36.770975]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   36.771628]  do_invalid_op+0x1b/0x20
[   36.772132]  invalid_op+0x18/0x20
[   36.772644] RIP: 0010:tun_get_user+0x2de3/0x36d0
[   36.773297] RSP: 0018:ffff8801d27af730 EFLAGS: 00010286
[   36.774008] RAX: dffffc0000000000 RBX: ffff8801d49dea98 RCX: dffffc0000000000
[   36.777475] RDX: ffffffff87024180 RSI: 0000000000000000 RDI: 0000000000000282
[   36.784711] RBP: ffff8801d27afae0 R08: 0000000000000001 R09: 0000000000000000
[   36.791963] R10: ffffffff87069320 R11: 0000000000000000 R12: ffff8801d1205e40
[   36.799199] R13: ffff8801d49deb08 R14: 0000000000000000 R15: ffff8801d29f0d40
[   36.806473]  ? tun_build_skb.isra.48+0x16e0/0x16e0
[   36.811371]  ? kmem_cache_alloc+0x12e/0x760
[   36.815660]  ? do_mmap+0x69b/0xd40
[   36.819167]  ? vm_mmap_pgoff+0x1de/0x280
[   36.823197]  ? SyS_mmap+0x16/0x20
[   36.826617]  ? entry_SYSCALL_64_fastpath+0x1f/0xbe
[   36.831518]  ? find_held_lock+0x35/0x1d0
[   36.835546]  ? check_noncircular+0x20/0x20
[   36.839761]  ? tun_get+0x1ab/0x2e0
[   36.843273]  ? lock_release+0xa40/0xa40
[   36.847220]  ? __lock_is_held+0xb6/0x140
[   36.851260]  ? tun_get+0x1d4/0x2e0
[   36.854768]  ? tun_chr_close+0x60/0x60
[   36.858624]  ? __check_object_size+0x25d/0x4f0
[   36.863177]  ? rcu_note_context_switch+0x710/0x710
[   36.868081]  tun_chr_write_iter+0xb9/0x160
[   36.872287]  do_iter_readv_writev+0x525/0x7f0
[   36.876754]  ? vfs_dedupe_file_range+0x8f0/0x8f0
[   36.881483]  ? rw_verify_area+0xe5/0x2b0
[   36.885526]  do_iter_write+0x154/0x540
[   36.889382]  ? dup_iter+0x260/0x260
[   36.892985]  vfs_writev+0x18a/0x340
[   36.896575]  ? __fget_light+0x297/0x380
[   36.900519]  ? vfs_iter_write+0xb0/0xb0
[   36.904462]  ? up_read+0x1a/0x40
[   36.907797]  ? __do_page_fault+0x3d6/0xd60
[   36.911999]  ? security_mmap_file+0x143/0x180
[   36.916470]  ? mm_fault_error+0x2c0/0x2c0
[   36.920594]  ? __fdget_pos+0x130/0x190
[   36.924450]  ? __fdget_raw+0x20/0x20
[   36.928134]  ? __do_page_fault+0xd60/0xd60
[   36.932341]  do_writev+0xfc/0x2a0
[   36.935761]  ? do_writev+0xfc/0x2a0
[   36.939361]  ? vfs_writev+0x340/0x340
[   36.943129]  ? entry_SYSCALL_64_fastpath+0x5/0xbe
[   36.947941]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   36.952930]  SyS_writev+0x27/0x30
[   36.956354]  entry_SYSCALL_64_fastpath+0x1f/0xbe
[   36.961076] RIP: 0033:0x4449a0
[   36.964232] RSP: 002b:00007fffbb3fd858 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
[   36.971906] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004449a0
[   36.979143] RDX: 0000000000000002 RSI: 00007fffbb3fd860 RDI: 0000000000000003
[   36.986381] RBP: 0000000000000082 R08: 0000000000000011 R09: 0000000000000004
[   36.993618] R10: 0000000068f78f4d R11: 0000000000000246 R12: 00000000004020b0
[   37.000857] R13: 0000000000402140 R14: 0000000000000000 R15: 0000000000000000
[   37.008243] Dumping ftrace buffer:
[   37.011792]    (ftrace buffer empty)
[   37.015471] Kernel Offset: disabled
[   37.019067] Rebooting in 86400 seconds..