==================================================================
BUG: KASAN: stack-out-of-bounds in __debug_check_no_obj_freed lib/debugobjects.c:777 [inline]
BUG: KASAN: stack-out-of-bounds in debug_check_no_obj_freed+0x45f/0x58d lib/debugobjects.c:817
Read of size 8 at addr ffff8881baa45e00 by task syz-executor3/17628

CPU: 1 PID: 17628 Comm: syz-executor3 Not tainted 4.20.0-rc6-next-20181217+ #172
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+0x244/0x39d lib/dump_stack.c:113
PANIC: double fault, error_code: 0x0
CPU: 0 PID: 6557 Comm: syz-executor4 Not tainted 4.20.0-rc6-next-20181217+ #172
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 print_address_description.cold.4+0x9/0x1ff mm/kasan/report.c:187
RIP: 0010:write_comp_data+0x0/0x70 kernel/kcov.c:116
Code: ff ff e8 43 7e 44 00 e9 a4 fc ff ff 4c 89 f7 e8 96 7d 44 00 e9 6d fc ff ff e8 fc e4 c8 ff 90 90 90 90 90 90 90 90 90 90 90 90 <55> 48 89 e5 [ 1022.304902]  kasan_report.cold.5+0x1b/0x39 mm/kasan/report.c:317