syzbot

ntfs3(loop0): Failed to initialize $Extend/$ObjId.
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc2-syzkaller-00260-g9e4c6c1ad9a1 #0 Not tainted
------------------------------------------------------
syz-executor363/5225 is trying to acquire lock:
ffff88802f752798 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0xaa/0x120 mm/memory.c:6700

but task is already holding lock:
ffff8880750e0100 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1109 [inline]
ffff8880750e0100 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ntfs_fiemap+0xff/0x180 fs/ntfs3/file.c:1350

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->ni_lock#2/5){+.+.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       ni_lock fs/ntfs3/ntfs_fs.h:1109 [inline]
       attr_data_get_block+0x44b/0x2f20 fs/ntfs3/attrib.c:917
       ntfs_file_mmap+0x4f2/0x850 fs/ntfs3/file.c:369
       call_mmap include/linux/fs.h:2172 [inline]
       mmap_region+0x1add/0x2990 mm/mmap.c:1440
       do_mmap+0x8f0/0x1000 mm/mmap.c:496
       vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588
       ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:542
       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 (&mm->mmap_lock){++++}-{3:3}:
       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+0x1384/0x2050 kernel/locking/lockdep.c:5202
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
       __might_fault+0xc6/0x120 mm/memory.c:6700
       _inline_copy_to_user include/linux/uaccess.h:183 [inline]
       _copy_to_user+0x2a/0xb0 lib/usercopy.c:26
       copy_to_user include/linux/uaccess.h:216 [inline]
       ni_fiemap+0x57c/0x18c0 fs/ntfs3/frecord.c:2139
       ntfs_fiemap+0x132/0x180 fs/ntfs3/file.c:1352
       ioctl_fiemap fs/ioctl.c:220 [inline]
       do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841
       __do_sys_ioctl fs/ioctl.c:905 [inline]
       __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
       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->ni_lock#2/5);
                               lock(&mm->mmap_lock);
                               lock(&ni->ni_lock#2/5);
  rlock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz-executor363/5225:
 #0: ffff8880750e0100 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1109 [inline]
 #0: ffff8880750e0100 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ntfs_fiemap+0xff/0x180 fs/ntfs3/file.c:1350

stack backtrace:
CPU: 1 UID: 0 PID: 5225 Comm: syz-executor363 Not tainted 6.12.0-rc2-syzkaller-00260-g9e4c6c1ad9a1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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+0x1384/0x2050 kernel/locking/lockdep.c:5202
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 __might_fault+0xc6/0x120 mm/memory.c:6700
 _inline_copy_to_user include/linux/uaccess.h:183 [inline]
 _copy_to_user+0x2a/0xb0 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:216 [inline]
 ni_fiemap+0x57c/0x18c0 fs/ntfs3/frecord.c:2139
 ntfs_fiemap+0x132/0x180 fs/ntfs3/file.c:1352
 ioctl_fiemap fs/ioctl.c:220 [inline]
 do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841
 __do_sys_ioctl fs/ioctl.c:905 [inline]
 __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
 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: 0033:0x7f6791588e59
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe5e73edb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6791588e59
RDX: 0000000020000280 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 00007f679161c5f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 00007ffe5e73edf0
R13: 00007ffe5e73f018 R14: 431bde82d7b634db R15: 00007f67915d203b
 </TASK>