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: 16757 Comm: syz-executor6 Not tainted 4.15.0-rc9+ #208
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__ptr_ring_peek include/linux/ptr_ring.h:190 [inline]
RIP: 0010:__ptr_ring_consume include/linux/ptr_ring.h:286 [inline]
RIP: 0010:ptr_ring_consume include/linux/ptr_ring.h:322 [inline]
RIP: 0010:tun_ring_recv drivers/net/tun.c:2127 [inline]
RIP: 0010:tun_do_read+0xf05/0x2600 drivers/net/tun.c:2178
RSP: 0018:ffff8801c0307920 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000010 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000002 RDI: ffff8801d5e17d0c
RBP: ffff8801c0307c88 R08: 1ffff10038060e63 R09: 0000000000000004
R10: ffff8801c03077d8 R11: 0000000000000004 R12: ffff8801c0307c60
R13: ffff8801d5e17640 R14: 0000000000000800 R15: 0000000000000000
FS:  0000000001660940(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000047e5d0 CR3: 00000001c0708004 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tun_chr_read_iter+0xe5/0x1e0 drivers/net/tun.c:2210
 call_read_iter include/linux/fs.h:1766 [inline]
 new_sync_read fs/read_write.c:401 [inline]
 __vfs_read+0x6a7/0xa00 fs/read_write.c:413
 vfs_read+0x11e/0x350 fs/read_write.c:447
 SYSC_read fs/read_write.c:573 [inline]
 SyS_read+0xef/0x220 fs/read_write.c:566
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x40d130
RSP: 002b:0000000000a2fa18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000001660914 RCX: 000000000040d130
RDX: 00000000000003e8 RSI: 0000000000a2fb50 RDI: 0000000000000012
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000001660940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000002d9a
R13: 000000000000000f R14: 0000000000067591 R15: 0000000000000001
Code: ea 03 80 3c 02 00 0f 85 0a 12 00 00 49 8b 95 08 07 00 00 49 63 cf 48 b8 00 00 00 00 00 fc ff df 48 8d 1c ca 48 89 de 48 c1 ee 03 <80> 3c 06 00 0f 85 b8 11 00 00 48 8b 1b 48 89 8d b8 fc ff ff 48 
RIP: __ptr_ring_peek include/linux/ptr_ring.h:190 [inline] RSP: ffff8801c0307920
RIP: __ptr_ring_consume include/linux/ptr_ring.h:286 [inline] RSP: ffff8801c0307920
RIP: ptr_ring_consume include/linux/ptr_ring.h:322 [inline] RSP: ffff8801c0307920
RIP: tun_ring_recv drivers/net/tun.c:2127 [inline] RSP: ffff8801c0307920
RIP: tun_do_read+0xf05/0x2600 drivers/net/tun.c:2178 RSP: ffff8801c0307920
---[ end trace 77361a7331fb3281 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..