loop3: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.356/5728 is trying to acquire lock:
ffff888075747958 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0xa6/0x120 mm/memory.c:5850

but task is already holding lock:
ffff8880540e5980 (&ni->ni_lock/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1103 [inline]
ffff8880540e5980 (&ni->ni_lock/5){+.+.}-{3:3}, at: ntfs_fiemap+0xc4/0x130 fs/ntfs3/file.c:1171

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->ni_lock/5){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747
       ni_lock fs/ntfs3/ntfs_fs.h:1103 [inline]
       attr_data_get_block+0x339/0x1b60 fs/ntfs3/attrib.c:951
       ntfs_get_block_vbo+0x406/0xc80 fs/ntfs3/inode.c:597
       __block_write_begin_int+0x55d/0x1a80 fs/buffer.c:1991
       __block_write_begin fs/buffer.c:2041 [inline]
       block_write_begin+0x96/0x1e0 fs/buffer.c:2102
       ntfs_extend_initialized_size+0x374/0x760 fs/ntfs3/file.c:159
       ntfs_file_mmap+0x556/0x700 fs/ntfs3/file.c:324
       call_mmap include/linux/fs.h:2270 [inline]
       mmap_file+0x5d/0xb0 mm/util.c:1109
       __mmap_region mm/mmap.c:2772 [inline]
       mmap_region+0xdda/0x1ca0 mm/mmap.c:2916
       do_mmap+0x964/0xfd0 mm/mmap.c:1436
       vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520
       ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
       lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
       __might_fault+0xc2/0x120 mm/memory.c:5850
       _copy_to_user+0x27/0x130 lib/usercopy.c:36
       copy_to_user include/linux/uaccess.h:169 [inline]
       ni_fiemap+0x1136/0x1370 fs/ntfs3/frecord.c:2142
       ntfs_fiemap+0xd7/0x130 fs/ntfs3/file.c:1173
       ioctl_fiemap fs/ioctl.c:219 [inline]
       do_vfs_ioctl+0x1418/0x1d40 fs/ioctl.c:810
       __do_sys_ioctl fs/ioctl.c:868 [inline]
       __se_sys_ioctl+0x83/0x170 fs/ioctl.c:856
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/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->ni_lock/5);
                               lock(&mm->mmap_lock);
                               lock(&ni->ni_lock/5);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz.3.356/5728:
 #0: ffff8880540e5980 (&ni->ni_lock/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1103 [inline]
 #0: ffff8880540e5980 (&ni->ni_lock/5){+.+.}-{3:3}, at: ntfs_fiemap+0xc4/0x130 fs/ntfs3/file.c:1171

stack backtrace:
CPU: 0 PID: 5728 Comm: syz.3.356 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
 __might_fault+0xc2/0x120 mm/memory.c:5850
 _copy_to_user+0x27/0x130 lib/usercopy.c:36
 copy_to_user include/linux/uaccess.h:169 [inline]
 ni_fiemap+0x1136/0x1370 fs/ntfs3/frecord.c:2142
 ntfs_fiemap+0xd7/0x130 fs/ntfs3/file.c:1173
 ioctl_fiemap fs/ioctl.c:219 [inline]
 do_vfs_ioctl+0x1418/0x1d40 fs/ioctl.c:810
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl+0x83/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcb1599acb9
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:00007fcb1678b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcb15c15fa0 RCX: 00007fcb1599acb9
RDX: 0000200000000280 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 00007fcb15a08bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcb15c16038 R14: 00007fcb15c15fa0 R15: 00007fffe13e4e88
 </TASK>