KASAN: stack-out-of-bounds Read in __delayacct_add

==================================================================
BUG: KASAN: stack-out-of-bounds in __delayacct_add_tsk+0x62c/0x650 kernel/delayacct.c:134
Read of size 8 at addr ffff8801b9d36c88 by task syz-executor6/16642

CPU: 1 PID: 16642 Comm: syz-executor6 Not tainted 4.18.0-rc3+ #48
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
PANIC: double fault, error_code: 0x0
CPU: 0 PID: 16629 Comm: syz-executor2 Not tainted 4.18.0-rc3+ #48
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__lock_acquire+0x2e/0x5020 kernel/locking/lockdep.c:3294
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
Code: 41 57 
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
41 
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
89 cf 
 __delayacct_add_tsk+0x62c/0x650 kernel/delayacct.c:134
41 56 
 delayacct_add_tsk include/linux/delayacct.h:137 [inline]
 fill_tgid_exit kernel/taskstats.c:282 [inline]
 taskstats_exit+0x2d2/0xf10 kernel/taskstats.c:611
41 55 
49 89 
fd 41 
54 45 
89 
cc 53 
65 4c 
8b 34 
25 
40 ee 
01 00 
 do_exit+0x52c/0x2750 kernel/exit.c:850
48 83 
e4 f0 
48 81 
ec 60 
03 
00 00 
48 8b 
45 10 
<89> 94 
24 80 
00 00 
00 48 
ba 00 
00 00 
00 00 
fc ff 
df 48 
89 84 
24 98 
RSP: 0018:ffff8801b5ffef20 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 1ffff10036bffe61 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff88f92620
RBP: ffff8801b5fff2b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000000 R12: 0000000000000000
R13: ffffffff88f92620 R14: ffff88019a27a700 R15: 0000000000000002
FS:  0000000001094940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8801b5ffef18 CR3: 00000001c869a000 CR4: 00000000001406f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace: