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: 0 PID: 10274 Comm: syz-executor6 Not tainted 4.15.0-rc2-next-20171204+ #58
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: 00000000dc7bc5e8 task.stack: 000000004392b2d7
RIP: 0010:string+0xb4/0x200 lib/vsprintf.c:595
RSP: 0018:ffff8801d8b17868 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: fffffffffffffffe RCX: ffffffff8514cfef
RDX: 000dccad8dce4e8e RSI: ffffc900043ee000 RDI: ffff8801d8b17888
RBP: ffff8801d8b178b8 R08: ffffed0039f504ce R09: ffffed0039f504ce
R10: 0000000000000002 R11: ffffed0039f504cd R12: 006e656c6e727474
R13: 006e656c6e727473 R14: ffffffffffffffff R15: ffff8801cfa8266b
FS:  00007f1c125be700(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020508000 CR3: 00000001ce84d000 CR4: 00000000001406f0
Call Trace:
 vsnprintf+0x863/0x1900 lib/vsprintf.c:2282
 seq_vprintf+0xe3/0x1a0 fs/seq_file.c:397
 seq_printf+0xb3/0xe0 fs/seq_file.c:412
 show_timer+0x1ee/0x2b0 fs/proc/base.c:2303
 seq_read+0xb5a/0x13d0 fs/seq_file.c:269
 do_loop_readv_writev fs/read_write.c:673 [inline]
 do_iter_read+0x3db/0x5b0 fs/read_write.c:897
 vfs_readv+0x121/0x1c0 fs/read_write.c:959
 do_preadv+0x11b/0x1a0 fs/read_write.c:1043
 SYSC_preadv fs/read_write.c:1093 [inline]
 SyS_preadv+0x30/0x40 fs/read_write.c:1088
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x4529d9
RSP: 002b:00007f1c125bdc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 00000000004529d9
RDX: 0000000000000008 RSI: 0000000020508000 RDI: 0000000000000013
RBP: 0000000000000324 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f1c00
R13: 00000000ffffffff R14: 00007f1c125be6d4 R15: 0000000000000000
Code: 01 00 00 e8 5f 6c 5b fc 4d 85 f6 0f 84 10 01 00 00 e8 51 6c 5b fc 4c 89 ea 48 b8 00 00 00 00 00 fc ff df 4d 8d 65 01 48 c1 ea 03 <0f> b6 04 02 4c 89 ea 83 e2 07 38 d0 7f 08 84 c0 0f 85 ec 00 00 
RIP: string+0xb4/0x200 lib/vsprintf.c:595 RSP: ffff8801d8b17868
---[ end trace a888d6e464c99c9a ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
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Kernel Offset: disabled