loop4: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.4.1620/10358 is trying to acquire lock:
ffff88801979c270 (&wnd->rw_lock){++++}-{3:3}, at: ntfs_look_for_free_space+0xda/0x650 fs/ntfs3/fsntfs.c:362

but task is already holding lock:
ffff88805de7d2d0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_set_size+0x140/0x200 fs/ntfs3/inode.c:849

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
       ntfs_dir_emit fs/ntfs3/dir.c:338 [inline]
       ntfs_read_hdr+0x7d4/0xc30 fs/ntfs3/dir.c:386
       ntfs_readdir+0xacb/0xeb0 fs/ntfs3/dir.c:497
       iterate_dir+0x1c2/0x580 fs/readdir.c:106
       __do_sys_getdents fs/readdir.c:322 [inline]
       __se_sys_getdents+0xf6/0x260 fs/readdir.c:307
       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_set_size+0x164/0x200 fs/ntfs3/inode.c:851
       ntfs_extend+0x157/0x4d0 fs/ntfs3/file.c:335
       ntfs3_setattr+0x2aa/0xb80 fs/ntfs3/file.c:708
       notify_change+0xb0d/0xe10 fs/attr.c:499
       do_truncate+0x1b0/0x240 fs/open.c:66
       vfs_truncate+0x266/0x300 fs/open.c:112
       do_sys_truncate+0xf6/0x1c0 fs/open.c:135
       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 ***

4 locks held by syz.4.1620/10358:
 #0: ffff888019798418 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
 #1: ffff88805de7d4d0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #1: ffff88805de7d4d0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: do_truncate+0x19c/0x240 fs/open.c:64
 #2: ffff88805de7d220 (&ni->ni_lock#3/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1120 [inline]
 #2: ffff88805de7d220 (&ni->ni_lock#3/5){+.+.}-{3:3}, at: ntfs_set_size+0x131/0x200 fs/ntfs3/inode.c:848
 #3: ffff88805de7d2d0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_set_size+0x140/0x200 fs/ntfs3/inode.c:849

stack backtrace:
CPU: 0 PID: 10358 Comm: syz.4.1620 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_set_size+0x164/0x200 fs/ntfs3/inode.c:851
 ntfs_extend+0x157/0x4d0 fs/ntfs3/file.c:335
 ntfs3_setattr+0x2aa/0xb80 fs/ntfs3/file.c:708
 notify_change+0xb0d/0xe10 fs/attr.c:499
 do_truncate+0x1b0/0x240 fs/open.c:66
 vfs_truncate+0x266/0x300 fs/open.c:112
 do_sys_truncate+0xf6/0x1c0 fs/open.c:135
 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: 0033:0x7fef3579c629
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:00007fef365fa028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007fef35a15fa0 RCX: 00007fef3579c629
RDX: 0000000000000000 RSI: 0000000000103000 RDI: 0000200000000000
RBP: 00007fef35832b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fef35a16038 R14: 00007fef35a15fa0 R15: 00007fff6537d5f8
 </TASK>
ntfs3: loop4: ino=0, "file1" failed to extend initialized size to 103000.