syzbot

loop0: detected capacity change from 0 to 4096
ntfs3: loop0: Different NTFS sector size (1024) and media sector size (512).
ntfs3: loop0: Mark volume as dirty due to NTFS errors
ntfs3: loop0: Failed to load $Extend (-22).
ntfs3: loop0: Failed to initialize $Extend.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.20/5926 is trying to acquire lock:
ffff88802f0cc270 (&wnd->rw_lock){++++}-{3:3}, at: ntfs_look_for_free_space+0xda/0x650 fs/ntfs3/fsntfs.c:362

but task is already holding lock:
ffff88805e40f7b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_extend_mft+0x145/0x460 fs/ntfs3/fsntfs.c:511

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->file.run_lock#2){++++}-{3:3}:
       down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
       run_unpack_ex+0x7fb/0xb80 fs/ntfs3/run.c:1126
       ntfs_read_mft fs/ntfs3/inode.c:401 [inline]
       ntfs_iget5+0x2475/0x38a0 fs/ntfs3/inode.c:535
       dir_search_u+0x1fe/0x2e0 fs/ntfs3/dir.c:264
       ntfs_lookup+0xfb/0x1f0 fs/ntfs3/namei.c:85
       lookup_one_qstr_excl+0x112/0x250 fs/namei.c:1617
       do_unlinkat+0x19d/0x590 fs/namei.c:4385
       __do_sys_unlink fs/namei.c:4447 [inline]
       __se_sys_unlink fs/namei.c:4445 [inline]
       __x64_sys_unlink+0x49/0x50 fs/namei.c:4445
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&wnd->rw_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
       lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
       down_write_nested+0x9e/0x200 kernel/locking/rwsem.c:1689
       ntfs_look_for_free_space+0xda/0x650 fs/ntfs3/fsntfs.c:362
       attr_allocate_clusters+0x1be/0x6b0 fs/ntfs3/attrib.c:159
       attr_set_size+0x14cb/0x2ce0 fs/ntfs3/attrib.c:575
       ntfs_extend_mft+0x16a/0x460 fs/ntfs3/fsntfs.c:512
       ntfs_look_free_mft+0x644/0xd70 fs/ntfs3/fsntfs.c:709
       ntfs_create_inode+0x53d/0x3700 fs/ntfs3/inode.c:1345
       ntfs_create+0x42/0x60 fs/ntfs3/namei.c:112
       vfs_create+0x1f4/0x360 fs/namei.c:3198
       do_mknodat+0x3d0/0x500 fs/namei.c:4049
       __do_sys_mknod fs/namei.c:4082 [inline]
       __se_sys_mknod fs/namei.c:4080 [inline]
       __x64_sys_mknod+0x8e/0xa0 fs/namei.c:4080
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ni->file.run_lock#2);
                               lock(&wnd->rw_lock);
                               lock(&ni->file.run_lock#2);
  lock(&wnd->rw_lock);

 *** DEADLOCK ***

5 locks held by syz.0.20/5926:
 #0: ffff88802f0ce418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
 #1: ffff888072752ff0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:839 [inline]
 #1: ffff888072752ff0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x20c/0x480 fs/namei.c:3890
 #2: ffff888072752d40 (&ni->ni_lock#3/6){+.+.}-{3:3}, at: ni_lock_dir fs/ntfs3/ntfs_fs.h:1125 [inline]
 #2: ffff888072752d40 (&ni->ni_lock#3/6){+.+.}-{3:3}, at: ntfs_create_inode+0x18c/0x3700 fs/ntfs3/inode.c:1259
 #3: ffff88802f0cc128 (&wnd->rw_lock/1){+.+.}-{3:3}, at: ntfs_look_free_mft+0x171/0xd70 fs/ntfs3/fsntfs.c:571
 #4: ffff88805e40f7b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_extend_mft+0x145/0x460 fs/ntfs3/fsntfs.c:511

stack backtrace:
CPU: 1 PID: 5926 Comm: syz.0.20 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
 down_write_nested+0x9e/0x200 kernel/locking/rwsem.c:1689
 ntfs_look_for_free_space+0xda/0x650 fs/ntfs3/fsntfs.c:362
 attr_allocate_clusters+0x1be/0x6b0 fs/ntfs3/attrib.c:159
 attr_set_size+0x14cb/0x2ce0 fs/ntfs3/attrib.c:575
 ntfs_extend_mft+0x16a/0x460 fs/ntfs3/fsntfs.c:512
 ntfs_look_free_mft+0x644/0xd70 fs/ntfs3/fsntfs.c:709
 ntfs_create_inode+0x53d/0x3700 fs/ntfs3/inode.c:1345
 ntfs_create+0x42/0x60 fs/ntfs3/namei.c:112
 vfs_create+0x1f4/0x360 fs/namei.c:3198
 do_mknodat+0x3d0/0x500 fs/namei.c:4049
 __do_sys_mknod fs/namei.c:4082 [inline]
 __se_sys_mknod fs/namei.c:4080 [inline]
 __x64_sys_mknod+0x8e/0xa0 fs/namei.c:4080
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f68f439c629
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:00007ffe1c141de8 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f68f4615fa0 RCX: 00007f68f439c629
RDX: 0000000000000701 RSI: 0000000000000000 RDI: 0000200000000000
RBP: 00007f68f4432b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f68f4615fac R14: 00007f68f4615fa0 R15: 00007f68f4615fa0
 </TASK>
ntfs3: loop0: ino=0, attr_set_size