kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 3297 Comm: syz-executor4 Not tainted 4.14.0-rc5-mm1+ #18
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801c99ba580 task.stack: ffff8801c9a60000
RIP: 0010:__read_once_size include/linux/compiler.h:276 [inline]
RIP: 0010:hrtimer_active+0x211/0x410 kernel/time/hrtimer.c:1142
RSP: 0018:ffff8801c9a67738 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff1003934cf14 RCX: ffffffff815ef93f
RDX: 0000000000000069 RSI: ffffc90003365000 RDI: ffff8801c9b9fa60
RBP: ffff8801c9a67878 R08: ffffffff83f9e367 R09: 0000000000000004
R10: ffff8801c9a67be0 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffed003934cef2 R15: dffffc0000000000
FS:  00007f5c140f1700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000001ab4cd8 CR3: 00000001c99d8000 CR4: 00000000001406e0
DR0: 0000000020001000 DR1: 0000000020001000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 hrtimer_try_to_cancel+0x91/0x5c0 kernel/time/hrtimer.c:1006
 hrtimer_cancel+0x22/0x40 kernel/time/hrtimer.c:1032
 napi_disable+0x87/0xa0 net/core/dev.c:5551
 tun_napi_disable drivers/net/tun.c:290 [inline]
 __tun_detach+0xe26/0x1570 drivers/net/tun.c:617
 tun_detach drivers/net/tun.c:664 [inline]
 tun_chr_close+0x44/0x60 drivers/net/tun.c:2835
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:112
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x296/0x310 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath+0x42f/0x510 arch/x86/entry/common.c:266
 entry_SYSCALL_64_fastpath+0xbc/0xbe
RIP: 0033:0x452719
RSP: 002b:00007f5c140f0be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000021
RAX: 0000000000000015 RBX: 0000000000758020 RCX: 0000000000452719
RDX: 0000000000000000 RSI: 0000000000000015 RDI: 0000000000000014
RBP: 0000000000000059 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006ee8f8
R13: 00000000ffffffff R14: 00007f5c140f16d4 R15: 0000000000000000
Code: c6 00 00 48 8b 85 d8 fe ff ff 48 c1 e8 03 42 80 3c 38 00 0f 85 f2 01 00 00 48 8b 85 e8 fe ff ff 4c 8b 60 30 4c 89 e0 48 c1 e8 03 <42> 80 3c 38 00 0f 85 c8 01 00 00 48 8b 85 f0 fe ff ff 49 8b 1c 
RIP: __read_once_size include/linux/compiler.h:276 [inline] RSP: ffff8801c9a67738
RIP: hrtimer_active+0x211/0x410 kernel/time/hrtimer.c:1142 RSP: ffff8801c9a67738
---[ end trace 6ab47228e973f865 ]---