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BUG: KASAN: use-after-free in class_equal+0x40/0x50 kernel/locking/lockdep.c:1579
Read of size 8 at addr ffff88807c414390 by task syz-executor.4/9975

CPU: 1 PID: 9975 Comm: syz-executor.4 Not tainted 5.2.0-rc7-next-20190702 #27
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:

Allocated by task 2250377184:
------------[ cut here ]------------
kernel BUG at mm/slab.c:4180!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 9975 Comm: syz-executor.4 Not tainted 5.2.0-rc7-next-20190702 #27
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__check_heap_object+0xa5/0xb3 mm/slab.c:4180
Code: 2b 48 c7 c7 8d 4d 87 88 e8 78 e3 07 00 5d c3 41 8b 91 3c 01 00 00 48 29 c7 48 39 d7 77 bd 48 01 d0 48 29 c8 4c 39 c0 72 b2 c3 <0f> 0b 48 c7 c7 8d 4d 87 88 e8 99 e8 07 00 4c 8d 45 c4 89 d9 48 c7
RSP: 0018:ffff88807c413a88 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000000000000c
RDX: ffff88807c412900 RSI: 0000000000000000 RDI: ffff88807c413b40
RBP: ffff88807c413ad8 R08: 0000000000000002 R09: ffff88821bc47380
R10: 000000000000101a R11: ffffea0001f10487 R12: ffff88807c413b40
R13: ffffea0001f10480 R14: ffff88807c413b42 R15: 0000000000000001
FS:  000055555555f940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8c278838 CR3: 0000000087ec3000 CR4: 00000000001506e0
Call Trace:
Modules linked in:
---[ end trace 6b4485695cebe6ba ]---
RIP: 0010:__check_heap_object+0xa5/0xb3 mm/slab.c:4180
Code: 2b 48 c7 c7 8d 4d 87 88 e8 78 e3 07 00 5d c3 41 8b 91 3c 01 00 00 48 29 c7 48 39 d7 77 bd 48 01 d0 48 29 c8 4c 39 c0 72 b2 c3 <0f> 0b 48 c7 c7 8d 4d 87 88 e8 99 e8 07 00 4c 8d 45 c4 89 d9 48 c7
RSP: 0018:ffff88807c413a88 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000000000000c
RDX: ffff88807c412900 RSI: 0000000000000000 RDI: ffff88807c413b40
RBP: ffff88807c413ad8 R08: 0000000000000002 R09: ffff88821bc47380
R10: 000000000000101a R11: ffffea0001f10487 R12: ffff88807c413b40
R13: ffffea0001f10480 R14: ffff88807c413b42 R15: 0000000000000001
FS:  000055555555f940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8c278838 CR3: 0000000087ec3000 CR4: 00000000001506e0