syzbot

======================================================
WARNING: possible circular locking dependency detected
6.1.69-syzkaller #0 Not tainted
------------------------------------------------------
kworker/u4:2/33 is trying to acquire lock:
ffff8880743c0940 (&rl->lock){++++}-{3:3}, at: ntfs_read_block fs/ntfs/aops.c:248 [inline]
ffff8880743c0940 (&rl->lock){++++}-{3:3}, at: ntfs_read_folio+0x14c9/0x29d0 fs/ntfs/aops.c:436

but task is already holding lock:
ffff88807102ecd0 (&ni->mrec_lock){+.+.}-{3:3}, at: map_mft_record+0x48/0x630 fs/ntfs/mft.c:154

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->mrec_lock){+.+.}-{3:3}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
       map_mft_record+0x48/0x630 fs/ntfs/mft.c:154
       ntfs_attr_extend_allocation+0x535/0x4340 fs/ntfs/attrib.c:2002
       ntfs_prepare_file_for_write fs/ntfs/file.c:391 [inline]
       ntfs_file_write_iter+0x3a9/0x19f0 fs/ntfs/file.c:1915
       call_write_iter include/linux/fs.h:2248 [inline]
       new_sync_write fs/read_write.c:491 [inline]
       vfs_write+0x7ae/0xba0 fs/read_write.c:584
       ksys_write+0x19c/0x2c0 fs/read_write.c:637
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&rl->lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       down_read+0xad/0xa30 kernel/locking/rwsem.c:1520
       ntfs_read_block fs/ntfs/aops.c:248 [inline]
       ntfs_read_folio+0x14c9/0x29d0 fs/ntfs/aops.c:436
       filemap_read_folio+0x199/0x780 mm/filemap.c:2461
       do_read_cache_folio+0x2ee/0x810 mm/filemap.c:3589
       do_read_cache_page+0x32/0x220 mm/filemap.c:3631
       read_mapping_page include/linux/pagemap.h:758 [inline]
       ntfs_map_page fs/ntfs/aops.h:75 [inline]
       ntfs_sync_mft_mirror+0x25b/0x1ad0 fs/ntfs/mft.c:480
       write_mft_record_nolock+0x1151/0x18d0 fs/ntfs/mft.c:787
       write_mft_record+0x149/0x310 fs/ntfs/mft.h:95
       __ntfs_write_inode+0x6ff/0xbb0 fs/ntfs/inode.c:3050
       write_inode fs/fs-writeback.c:1460 [inline]
       __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677
       writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903
       __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974
       wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079
       wb_check_background_flush fs/fs-writeback.c:2145 [inline]
       wb_do_writeback fs/fs-writeback.c:2233 [inline]
       wb_workfn+0xc9e/0x1020 fs/fs-writeback.c:2260
       process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
       worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
       kthread+0x28d/0x320 kernel/kthread.c:376
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ni->mrec_lock);
                               lock(&rl->lock);
                               lock(&ni->mrec_lock);
  lock(&rl->lock);

 *** DEADLOCK ***

4 locks held by kworker/u4:2/33:
 #0: ffff888141ab6938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90000aa7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffff88807b7b40e0 (&type->s_umount_key#63){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415
 #3: ffff88807102ecd0 (&ni->mrec_lock){+.+.}-{3:3}, at: map_mft_record+0x48/0x630 fs/ntfs/mft.c:154

stack backtrace:
CPU: 0 PID: 33 Comm: kworker/u4:2 Not tainted 6.1.69-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: writeback wb_workfn
 (flush-7:2)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2fa/0x3b0 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+0x1661/0x5950 kernel/locking/lockdep.c:3825
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 down_read+0xad/0xa30 kernel/locking/rwsem.c:1520
 ntfs_read_block fs/ntfs/aops.c:248 [inline]
 ntfs_read_folio+0x14c9/0x29d0 fs/ntfs/aops.c:436
 filemap_read_folio+0x199/0x780 mm/filemap.c:2461
 do_read_cache_folio+0x2ee/0x810 mm/filemap.c:3589
 do_read_cache_page+0x32/0x220 mm/filemap.c:3631
 read_mapping_page include/linux/pagemap.h:758 [inline]
 ntfs_map_page fs/ntfs/aops.h:75 [inline]
 ntfs_sync_mft_mirror+0x25b/0x1ad0 fs/ntfs/mft.c:480
 write_mft_record_nolock+0x1151/0x18d0 fs/ntfs/mft.c:787
 write_mft_record+0x149/0x310 fs/ntfs/mft.h:95
 __ntfs_write_inode+0x6ff/0xbb0 fs/ntfs/inode.c:3050
 write_inode fs/fs-writeback.c:1460 [inline]
 __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677
 writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903
 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974
 wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079
 wb_check_background_flush fs/fs-writeback.c:2145 [inline]
 wb_do_writeback fs/fs-writeback.c:2233 [inline]
 wb_workfn+0xc9e/0x1020 fs/fs-writeback.c:2260
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>