============================================
WARNING: possible recursive locking detected
6.10.0-rc2-syzkaller-00366-g771ed66105de #0 Not tainted
--------------------------------------------
syz-executor.3/5911 is trying to acquire lock:
ffff88801ef64420 (sb_writers#4){.+.+}-{0:0}, at: ovl_do_copy_up fs/overlayfs/copy_up.c:967 [inline]
ffff88801ef64420 (sb_writers#4){.+.+}-{0:0}, at: ovl_copy_up_one+0x82a/0x3490 fs/overlayfs/copy_up.c:1168

but task is already holding lock:
ffff88801ef64420 (sb_writers#4){.+.+}-{0:0}, at: ovl_tmpfile+0x15b/0x6f0 fs/overlayfs/dir.c:1363

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(sb_writers#4);
  lock(sb_writers#4);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by syz-executor.3/5911:
 #0: ffff888027f8c420 (sb_writers#24){.+.+}-{0:0}, at: do_tmpfile fs/namei.c:3761 [inline]
 #0: ffff888027f8c420 (sb_writers#24){.+.+}-{0:0}, at: path_openat+0xc0f/0x29f0 fs/namei.c:3798
 #1: ffff88801ef64420 (sb_writers#4){.+.+}-{0:0}, at: ovl_tmpfile+0x15b/0x6f0 fs/overlayfs/dir.c:1363
 #2: ffff888011dc0528 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:657 [inline]
 #2: ffff888011dc0528 (&ovl_i_lock_key[depth]){+.+.}-{3:3}, at: ovl_copy_up_start+0x4d/0x2f0 fs/overlayfs/util.c:719

stack backtrace:
CPU: 3 PID: 5911 Comm: syz-executor.3 Not tainted 6.10.0-rc2-syzkaller-00366-g771ed66105de #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 check_deadlock kernel/locking/lockdep.c:3062 [inline]
 validate_chain kernel/locking/lockdep.c:3856 [inline]
 __lock_acquire+0x20e6/0x3b30 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1655 [inline]
 sb_start_write include/linux/fs.h:1791 [inline]
 ovl_start_write+0x130/0x310 fs/overlayfs/util.c:31
 ovl_do_copy_up fs/overlayfs/copy_up.c:967 [inline]
 ovl_copy_up_one+0x82a/0x3490 fs/overlayfs/copy_up.c:1168
 ovl_copy_up_flags+0x18d/0x200 fs/overlayfs/copy_up.c:1223
 ovl_create_tmpfile fs/overlayfs/dir.c:1317 [inline]
 ovl_tmpfile+0x2b8/0x6f0 fs/overlayfs/dir.c:1373
 vfs_tmpfile+0x2be/0x540 fs/namei.c:3701
 do_tmpfile fs/namei.c:3764 [inline]
 path_openat+0xc8e/0x29f0 fs/namei.c:3798
 do_filp_open+0x1dc/0x430 fs/namei.c:3834
 do_sys_openat2+0x17a/0x1e0 fs/open.c:1405
 do_sys_open fs/open.c:1420 [inline]
 __do_compat_sys_open fs/open.c:1471 [inline]
 __se_compat_sys_open fs/open.c:1469 [inline]
 __ia32_compat_sys_open+0x147/0x1e0 fs/open.c:1469
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf72aa579
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:00000000f5e9c5ac EFLAGS: 00000292 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 0000000020000100 RCX: 0000000000591002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 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