ntfs3(loop1): failed to c
ntfs3(loop1): failed to convert "0080" to macinuit
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.1.272/6734 is trying to acquire lock:
ffff88802c5862b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:609

but task is already holding lock:
ffff88805e9f6478 (&ni->ni_lock/5){+.+.}-{4:4}, at: ni_lock fs/ntfs3/ntfs_fs.h:1247 [inline]
ffff88805e9f6478 (&ni->ni_lock/5){+.+.}-{4:4}, at: ntfs_readdir+0x717/0xf70 fs/ntfs3/dir.c:541

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->ni_lock/5){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/rtmutex_api.c:561 [inline]
       mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:580
       ni_lock fs/ntfs3/ntfs_fs.h:1247 [inline]
       attr_data_get_block+0x1cd/0x2c0 fs/ntfs3/attrib.c:976
       ntfs_file_mmap_prepare+0x5b3/0xa20 fs/ntfs3/file.c:430
       vfs_mmap_prepare include/linux/fs.h:2069 [inline]
       call_mmap_prepare mm/vma.c:2776 [inline]
       __mmap_region mm/vma.c:2865 [inline]
       mmap_region+0xea5/0x2220 mm/vma.c:2966
       do_mmap+0xe0e/0x1310 mm/mmap.c:573
       vm_mmap_pgoff+0x275/0x4e0 mm/util.c:581
       ksys_mmap_pgoff+0x4a6/0x720 mm/mmap.c:619
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&mm->mmap_lock){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3209 [inline]
       check_prevs_add kernel/locking/lockdep.c:3328 [inline]
       validate_chain kernel/locking/lockdep.c:3952 [inline]
       __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
       lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
       down_read_killable+0xa4/0x220 kernel/locking/rwsem.c:1599
       mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:609
       get_mmap_lock_carefully mm/mmap_lock.c:450 [inline]
       lock_mm_and_find_vma+0x2d6/0x340 mm/mmap_lock.c:501
       do_user_addr_fault+0x343/0x1340 arch/x86/mm/fault.c:1366
       handle_page_fault arch/x86/mm/fault.c:1483 [inline]
       exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
       filldir64+0x2bc/0x620 fs/readdir.c:-1
       dir_emit include/linux/fs.h:3607 [inline]
       ntfs_dir_emit fs/ntfs3/dir.c:388 [inline]
       ntfs_read_hdr+0x8a7/0xc10 fs/ntfs3/dir.c:429
       ntfs_readdir+0x9ab/0xf70 fs/ntfs3/dir.c:589
       iterate_dir+0x2f1/0x4e0 fs/readdir.c:110
       __do_sys_getdents64 fs/readdir.c:399 [inline]
       __se_sys_getdents64+0xf1/0x280 fs/readdir.c:384
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ni->ni_lock/5);
                               lock(&mm->mmap_lock);
                               lock(&ni->ni_lock/5);
  rlock(&mm->mmap_lock);

 *** DEADLOCK ***

locks held by syz.1.272/6734: 3, last CPU#1:
 #0: ffff888036d02d28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259
 #1: ffff88805e9f6740 (&type->i_mutex_dir_key#8){++++}-{4:4}, at: iterate_dir+0x215/0x4e0 fs/readdir.c:103
 #2: ffff88805e9f6478 (&ni->ni_lock/5){+.+.}-{4:4}, at: ni_lock fs/ntfs3/ntfs_fs.h:1247 [inline]
 #2: ffff88805e9f6478 (&ni->ni_lock/5){+.+.}-{4:4}, at: ntfs_readdir+0x717/0xf70 fs/ntfs3/dir.c:541

stack backtrace:
CPU: 1 UID: 0 PID: 6734 Comm: syz.1.272 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087
 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219
 check_prev_add kernel/locking/lockdep.c:3209 [inline]
 check_prevs_add kernel/locking/lockdep.c:3328 [inline]
 validate_chain kernel/locking/lockdep.c:3952 [inline]
 __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288
 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
 down_read_killable+0xa4/0x220 kernel/locking/rwsem.c:1599
 mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:609
 get_mmap_lock_carefully mm/mmap_lock.c:450 [inline]
 lock_mm_and_find_vma+0x2d6/0x340 mm/mmap_lock.c:501
 do_user_addr_fault+0x343/0x1340 arch/x86/mm/fault.c:1366
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0010:filldir64+0x2bc/0x620 fs/readdir.c:369
Code: ea 2f 7f ff 0f 01 cb 48 8b 44 24 28 49 89 47 08 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 58 48 89 03 8b 4c 24 04 48 8d 43 10 <66> 89 08 8b 4c 24 14 80 e1 0f 48 8d 43 12 88 08 4a 8d 04 2b 48 83
RSP: 0018:ffffc90005bb7ab0 EFLAGS: 00050293
RAX: 0000200000001000 RBX: 0000200000000ff0 RCX: 0000000000000020
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000007
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10061833e9 R12: ffff88806291e000
R13: 0000000000000009 R14: 0000000000000009 R15: 0000200000000fd8
 dir_emit include/linux/fs.h:3607 [inline]
 ntfs_dir_emit fs/ntfs3/dir.c:388 [inline]
 ntfs_read_hdr+0x8a7/0xc10 fs/ntfs3/dir.c:429
 ntfs_readdir+0x9ab/0xf70 fs/ntfs3/dir.c:589
 iterate_dir+0x2f1/0x4e0 fs/readdir.c:110
 __do_sys_getdents64 fs/readdir.c:399 [inline]
 __se_sys_getdents64+0xf1/0x280 fs/readdir.c:384
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d71cde159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2d7133e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f2d71f65fa0 RCX: 00007f2d71cde159
RDX: 00000000000000e0 RSI: 0000200000000fc0 RDI: 0000000000000004
RBP: 00007f2d71d7506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2d71f66038 R14: 00007f2d71f65fa0 R15: 00007ffefc74e278
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	7f ff                	jg     0x1
   2:	0f 01 cb             	stac
   5:	48 8b 44 24 28       	mov    0x28(%rsp),%rax
   a:	49 89 47 08          	mov    %rax,0x8(%r15)
   e:	48 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%rbp
  15:	fc ff df
  18:	48 8b 44 24 58       	mov    0x58(%rsp),%rax
  1d:	48 89 03             	mov    %rax,(%rbx)
  20:	8b 4c 24 04          	mov    0x4(%rsp),%ecx
  24:	48 8d 43 10          	lea    0x10(%rbx),%rax
* 28:	66 89 08             	mov    %cx,(%rax) <-- trapping instruction
  2b:	8b 4c 24 14          	mov    0x14(%rsp),%ecx
  2f:	80 e1 0f             	and    $0xf,%cl
  32:	48 8d 43 12          	lea    0x12(%rbx),%rax
  36:	88 08                	mov    %cl,(%rax)
  38:	4a 8d 04 2b          	lea    (%rbx,%r13,1),%rax
  3c:	48                   	rex.W
  3d:	83                   	.byte 0x83