------------[ cut here ]------------
WARNING: CPU: 0 PID: 7878 at fs/inode.c:417 drop_nlink+0xac/0xd0 fs/inode.c:417
Modules linked in:
CPU: 0 UID: 0 PID: 7878 Comm: syz.0.441 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:drop_nlink+0xac/0xd0 fs/inode.c:417
Code: 48 8b 5d 28 be 08 00 00 00 48 8d bb 78 07 00 00 e8 09 eb e5 ff f0 48 ff 83 78 07 00 00 5b 5d e9 7a 80 80 ff e8 75 80 80 ff 90 <0f> 0b 90 c7 45 48 ff ff ff ff 5b 5d e9 63 80 80 ff e8 de e2 e5 ff
RSP: 0018:ffffc9000709f988 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff823a87bf
RDX: ffff888021504880 RSI: ffffffff823a882b RDI: 0000000000000005
RBP: ffff888023ef42d0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880124c4d38
R13: ffff888023ef42d0 R14: 0000000017521e33 R15: 0000000000002000
FS:  0000000000000000(0000) GS:ffff8880974c3000(0063) knlGS:00000000f548db40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000080000d00 CR3: 00000000655c1000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 shmem_unlink+0x183/0x350 mm/shmem.c:4041
 shmem_rename2+0x1f5/0x3a0 mm/shmem.c:4127
 vfs_rename+0xfba/0x22c0 fs/namei.c:5129
 ovl_do_rename fs/overlayfs/overlayfs.h:374 [inline]
 ovl_cleanup_and_whiteout+0x37f/0xba0 fs/overlayfs/dir.c:148
 ovl_remove_and_whiteout fs/overlayfs/dir.c:796 [inline]
 ovl_do_remove+0x98a/0x1040 fs/overlayfs/dir.c:915
 vfs_unlink+0x2fe/0x9b0 fs/namei.c:4586
 do_unlinkat+0x4c5/0x6a0 fs/namei.c:4650
 __do_sys_unlink fs/namei.c:4696 [inline]
 __se_sys_unlink fs/namei.c:4694 [inline]
 __ia32_sys_unlink+0xc4/0x110 fs/namei.c:4694
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf70be579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f548d55c EFLAGS: 00000296 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 0000000080000200 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	ret
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi