==================================================================
BUG: KASAN: slab-out-of-bounds in class_equal+0x40/0x50 kernel/locking/lockdep.c:1579
Read of size 8 at addr ffff88807b8d9dd0 by task syz-executor.4/9829

CPU: 0 PID: 9829 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 2072876792:
usercopy: Kernel memory overwrite attempt detected to SLAB object 'kmalloc-4k' (offset 4160, size 2)!
------------[ cut here ]------------
kernel BUG at mm/usercopy.c:98!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9829 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:usercopy_abort+0xbd/0xbf mm/usercopy.c:98
Code: c0 e8 3b 1f be ff 48 8b 55 c0 49 89 d9 4d 89 f0 ff 75 c8 4c 89 e1 4c 89 ee 48 c7 c7 20 41 96 87 ff 75 d0 41 57 e8 ab c5 a7 ff <0f> 0b e8 10 1f be ff e8 2b 38 f8 ff 8b 55 d4 4c 89 e1 49 89 d8 4c
RSP: 0018:ffff88807b8d9458 EFLAGS: 00010082
RAX: 0000000000000068 RBX: ffffffff8887113d RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815c0c96 RDI: ffffed100f71b27d
RBP: ffff88807b8d94b0 R08: 0000000000000068 R09: ffffed1015d044fa
R10: ffffed1015d044f9 R11: ffff8880ae8227cf R12: ffffffff88874d8d
R13: ffffffff87963f80 R14: ffffffff87963ec0 R15: ffffffff87963e80
FS:  0000555555801940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8c23cc40 CR3: 00000000892c6000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
Modules linked in:
---[ end trace ef5d5cc139c7a54b ]---
RIP: 0010:usercopy_abort+0xbd/0xbf mm/usercopy.c:98
Code: c0 e8 3b 1f be ff 48 8b 55 c0 49 89 d9 4d 89 f0 ff 75 c8 4c 89 e1 4c 89 ee 48 c7 c7 20 41 96 87 ff 75 d0 41 57 e8 ab c5 a7 ff <0f> 0b e8 10 1f be ff e8 2b 38 f8 ff 8b 55 d4 4c 89 e1 49 89 d8 4c
RSP: 0018:ffff88807b8d9458 EFLAGS: 00010082
RAX: 0000000000000068 RBX: ffffffff8887113d RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815c0c96 RDI: ffffed100f71b27d
RBP: ffff88807b8d94b0 R08: 0000000000000068 R09: ffffed1015d044fa
R10: ffffed1015d044f9 R11: ffff8880ae8227cf R12: ffffffff88874d8d
R13: ffffffff87963f80 R14: ffffffff87963ec0 R15: ffffffff87963e80
FS:  0000555555801940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff8c23cc40 CR3: 00000000892c6000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400