======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
kworker/u4:2/154 is trying to acquire lock:
ffff8880764080b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28

but task is already holding lock:
ffff888068dda988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x87/0x200 fs/hfsplus/extents.c:149

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}:
       __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       hfsplus_file_extend+0x1b3/0x1950 fs/hfsplus/extents.c:455
       hfsplus_bmap_reserve+0x11e/0x4f0 fs/hfsplus/btree.c:357
       __hfsplus_ext_write_extent+0x28d/0x5b0 fs/hfsplus/extents.c:104
       __hfsplus_ext_cache_extent+0x89/0xe20 fs/hfsplus/extents.c:186
       hfsplus_file_truncate+0x467/0xb40 fs/hfsplus/extents.c:597
       hfsplus_setattr+0x1c0/0x280 fs/hfsplus/inode.c:267
       notify_change+0xbcd/0xee0 fs/attr.c:505
       do_truncate+0x197/0x220 fs/open.c:65
       vfs_truncate+0x262/0x2f0 fs/open.c:111
       do_sys_truncate+0xdc/0x190 fs/open.c:134
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (&tree->tree_lock/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
       lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
       __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
       hfsplus_ext_write_extent_locked fs/hfsplus/extents.c:136 [inline]
       hfsplus_ext_write_extent+0x148/0x200 fs/hfsplus/extents.c:150
       hfsplus_write_inode+0x1e/0x5b0 fs/hfsplus/super.c:167
       write_inode fs/fs-writeback.c:1505 [inline]
       __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1715
       writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1940
       wb_writeback+0x443/0xb90 fs/fs-writeback.c:2114
       wb_do_writeback fs/fs-writeback.c:2257 [inline]
       wb_workfn+0x423/0xe60 fs/fs-writeback.c:2298
       process_one_work+0x863/0x1000 kernel/workqueue.c:2310
       worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
       kthread+0x436/0x520 kernel/kthread.c:334
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&HFSPLUS_I(inode)->extents_lock);
                               lock(&tree->tree_lock/1);
                               lock(&HFSPLUS_I(inode)->extents_lock);
  lock(&tree->tree_lock/1);

 *** DEADLOCK ***

3 locks held by kworker/u4:2/154:
 #0: ffff8881425e0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90001fa7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffff888068dda988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x87/0x200 fs/hfsplus/extents.c:149

stack backtrace:
CPU: 1 PID: 154 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 hfsplus_find_init+0x150/0x1c0 fs/hfsplus/bfind.c:28
 hfsplus_ext_write_extent_locked fs/hfsplus/extents.c:136 [inline]
 hfsplus_ext_write_extent+0x148/0x200 fs/hfsplus/extents.c:150
 hfsplus_write_inode+0x1e/0x5b0 fs/hfsplus/super.c:167
 write_inode fs/fs-writeback.c:1505 [inline]
 __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1715
 writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1940
 wb_writeback+0x443/0xb90 fs/fs-writeback.c:2114
 wb_do_writeback fs/fs-writeback.c:2257 [inline]
 wb_workfn+0x423/0xe60 fs/fs-writeback.c:2298
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
hfsplus: b-tree write err: -5, ino 4