syzbot

loop5: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc6-next-20241108-syzkaller #0 Not tainted
------------------------------------------------------
syz.5.360/6985 is trying to acquire lock:
ffff88807ceae270 (&wnd->rw_lock){++++}-{4:4}, at: mark_as_free_ex+0x3e/0x390 fs/ntfs3/fsntfs.c:2484

but task is already holding lock:
ffff88806af16fd8 (&ni->file.run_lock#2){++++}-{4:4}, at: ntfs_truncate fs/ntfs3/file.c:505 [inline]
ffff88806af16fd8 (&ni->file.run_lock#2){++++}-{4:4}, at: ntfs_setattr+0x6d3/0xb80 fs/ntfs3/file.c:824

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->file.run_lock#2){++++}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
       down_read+0xb1/0xa40 kernel/locking/rwsem.c:1524
       run_unpack_ex+0x55e/0x9e0 fs/ntfs3/run.c:1119
       ntfs_read_mft fs/ntfs3/inode.c:401 [inline]
       ntfs_iget5+0x1f9a/0x37b0 fs/ntfs3/inode.c:537
       ntfs_dir_emit fs/ntfs3/dir.c:335 [inline]
       ntfs_read_hdr+0x700/0xb80 fs/ntfs3/dir.c:383
       ntfs_readdir+0x91f/0xf00 fs/ntfs3/dir.c:494
       iterate_dir+0x571/0x800 fs/readdir.c:108
       __do_sys_getdents fs/readdir.c:322 [inline]
       __se_sys_getdents+0x1fd/0x4e0 fs/readdir.c:308
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&wnd->rw_lock){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
       down_write_nested+0xa2/0x220 kernel/locking/rwsem.c:1693
       mark_as_free_ex+0x3e/0x390 fs/ntfs3/fsntfs.c:2484
       run_deallocate_ex+0x244/0x5f0 fs/ntfs3/attrib.c:122
       attr_set_size+0x168d/0x4300 fs/ntfs3/attrib.c:753
       ntfs_truncate fs/ntfs3/file.c:506 [inline]
       ntfs_setattr+0x7a4/0xb80 fs/ntfs3/file.c:824
       notify_change+0xbca/0xe90 fs/attr.c:552
       do_truncate+0x220/0x310 fs/open.c:65
       handle_truncate fs/namei.c:3449 [inline]
       do_open fs/namei.c:3832 [inline]
       path_openat+0x2e1e/0x3590 fs/namei.c:3987
       do_filp_open+0x27f/0x4e0 fs/namei.c:4014
       do_sys_openat2+0x13e/0x1d0 fs/open.c:1402
       do_sys_open fs/open.c:1417 [inline]
       __do_sys_creat fs/open.c:1495 [inline]
       __se_sys_creat fs/open.c:1489 [inline]
       __x64_sys_creat+0x123/0x170 fs/open.c:1489
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

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.5.360/6985:
 #0: ffff88806c208420 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
 #1: ffff88806af171c0 (&sb->s_type->i_mutex_key#36){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:817 [inline]
 #1: ffff88806af171c0 (&sb->s_type->i_mutex_key#36){+.+.}-{4:4}, at: do_truncate+0x20c/0x310 fs/open.c:63
 #2: ffff88806af16f28 (&ni->ni_lock#2/5){+.+.}-{4:4}, at: ni_lock fs/ntfs3/ntfs_fs.h:1110 [inline]
 #2: ffff88806af16f28 (&ni->ni_lock#2/5){+.+.}-{4:4}, at: ntfs_truncate fs/ntfs3/file.c:503 [inline]
 #2: ffff88806af16f28 (&ni->ni_lock#2/5){+.+.}-{4:4}, at: ntfs_setattr+0x6bf/0xb80 fs/ntfs3/file.c:824
 #3: ffff88806af16fd8 (&ni->file.run_lock#2){++++}-{4:4}, at: ntfs_truncate fs/ntfs3/file.c:505 [inline]
 #3: ffff88806af16fd8 (&ni->file.run_lock#2){++++}-{4:4}, at: ntfs_setattr+0x6d3/0xb80 fs/ntfs3/file.c:824

stack backtrace:
CPU: 1 UID: 0 PID: 6985 Comm: syz.5.360 Not tainted 6.12.0-rc6-next-20241108-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
 down_write_nested+0xa2/0x220 kernel/locking/rwsem.c:1693
 mark_as_free_ex+0x3e/0x390 fs/ntfs3/fsntfs.c:2484
 run_deallocate_ex+0x244/0x5f0 fs/ntfs3/attrib.c:122
 attr_set_size+0x168d/0x4300 fs/ntfs3/attrib.c:753
 ntfs_truncate fs/ntfs3/file.c:506 [inline]
 ntfs_setattr+0x7a4/0xb80 fs/ntfs3/file.c:824
 notify_change+0xbca/0xe90 fs/attr.c:552
 do_truncate+0x220/0x310 fs/open.c:65
 handle_truncate fs/namei.c:3449 [inline]
 do_open fs/namei.c:3832 [inline]
 path_openat+0x2e1e/0x3590 fs/namei.c:3987
 do_filp_open+0x27f/0x4e0 fs/namei.c:4014
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_creat fs/open.c:1495 [inline]
 __se_sys_creat fs/open.c:1489 [inline]
 __x64_sys_creat+0x123/0x170 fs/open.c:1489
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbf2657e719
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbf273d0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fbf26735f80 RCX: 00007fbf2657e719
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020002440
RBP: 00007fbf265f139e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbf26735f80 R15: 00007fff3ade1be8
 </TASK>