page:ffffea000712e200 count:1 mapcount:0 mapping:ffff8801c4b88c00 index:0x0 compound_mapcount: 0
flags: 0x200000000008100(slab|head)
raw: 0200000000008100 ffff8801c4b88c00 0000000000000000 0000000100000001
raw: ffffea00072d2a20 ffffea0007110820 ffff8801dac02200 0000000000000000
page dumped because: kasan: bad access detected
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 577 Comm: syz-executor4 Tainted: G    B           4.14.0-rc5+ #141
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 panic+0x1e4/0x417 kernel/panic.c:181
 kasan_end_report+0x50/0x50 mm/kasan/report.c:176
 kasan_report_error mm/kasan/report.c:356 [inline]
 kasan_report+0x144/0x340 mm/kasan/report.c:409
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:435
 hlist_add_head include/linux/list.h:673 [inline]
 enqueue_timer kernel/time/timer.c:520 [inline]
 __internal_add_timer+0x275/0x2d0 kernel/time/timer.c:531
 internal_add_timer kernel/time/timer.c:573 [inline]
 __mod_timer kernel/time/timer.c:1024 [inline]
 mod_timer+0x622/0x15b0 kernel/time/timer.c:1071
 tun_flow_init drivers/net/tun.c:1098 [inline]
 tun_set_iff drivers/net/tun.c:2060 [inline]
 __tun_chr_ioctl+0x1b17/0x3d20 drivers/net/tun.c:2278
 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2523
 vfs_ioctl fs/ioctl.c:45 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685
 SYSC_ioctl fs/ioctl.c:700 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x452719
RSP: 002b:00007f6dcf361be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452719
RDX: 0000000020c4c000 RSI: 00000000400454ca RDI: 0000000000000020
RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a6f7ff R14: 00007f6dcf3629c0 R15: 0000000000000000
Shutting down cpus with NMI
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..