loop0: detected capacity change from 0 to 1024
======================================================
WARNING: possible circular locking dependency detected
6.15.0-syzkaller-03589-gfeacb1774bd5 #0 Not tainted
------------------------------------------------------
syz.0.0/5316 is trying to acquire lock:
ffff8880403c8108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458

but task is already holding lock:
ffff8880114e60b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&tree->tree_lock/1){+.+.}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:601 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746
       hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28
       hfsplus_file_truncate+0x383/0xb40 fs/hfsplus/extents.c:583
       hfsplus_delete_inode+0x180/0x230 fs/hfsplus/inode.c:-1
       hfsplus_unlink+0x4e3/0x730 fs/hfsplus/dir.c:405
       vfs_unlink+0x394/0x650 fs/namei.c:4586
       do_unlinkat+0x350/0x560 fs/namei.c:4650
       __do_sys_unlinkat fs/namei.c:4691 [inline]
       __se_sys_unlinkat fs/namei.c:4684 [inline]
       __x64_sys_unlinkat+0xd3/0xf0 fs/namei.c:4684
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3168 [inline]
       check_prevs_add kernel/locking/lockdep.c:3287 [inline]
       validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
       __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:601 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746
       hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458
       hfsplus_bmap_reserve+0x122/0x500 fs/hfsplus/btree.c:358
       __hfsplus_ext_write_extent+0x28d/0x5b0 fs/hfsplus/extents.c:104
       __hfsplus_ext_cache_extent+0x89/0xe30 fs/hfsplus/extents.c:186
       hfsplus_ext_read_extent fs/hfsplus/extents.c:218 [inline]
       hfsplus_file_extend+0x444/0x1990 fs/hfsplus/extents.c:462
       hfsplus_get_block+0x411/0x1530 fs/hfsplus/extents.c:245
       __block_write_begin_int+0x6b2/0x1900 fs/buffer.c:2151
       block_write_begin fs/buffer.c:2262 [inline]
       cont_write_begin+0x789/0xb50 fs/buffer.c:2601
       hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46
       cont_expand_zero fs/buffer.c:2528 [inline]
       cont_write_begin+0x2fa/0xb50 fs/buffer.c:2591
       hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46
       generic_cont_expand_simple+0x13f/0x210 fs/buffer.c:2492
       hfsplus_setattr+0x169/0x270 fs/hfsplus/inode.c:258
       notify_change+0xb33/0xe40 fs/attr.c:552
       do_truncate+0x1a4/0x220 fs/open.c:68
       vfs_truncate+0x493/0x520 fs/open.c:118
       do_sys_truncate+0xdb/0x190 fs/open.c:141
       __do_sys_truncate fs/open.c:153 [inline]
       __se_sys_truncate fs/open.c:151 [inline]
       __x64_sys_truncate+0x5b/0x70 fs/open.c:151
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

4 locks held by syz.0.0/5316:
 #0: ffff888034284428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
 #1: ffff8880403cb8f8 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:872 [inline]
 #1: ffff8880403cb8f8 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: do_truncate+0x171/0x220 fs/open.c:63
 #2: ffff8880403cb708 (&hip->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458
 #3: ffff8880114e60b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28

stack backtrace:
CPU: 0 UID: 0 PID: 5316 Comm: syz.0.0 Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046
 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3168 [inline]
 check_prevs_add kernel/locking/lockdep.c:3287 [inline]
 validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 __mutex_lock_common kernel/locking/mutex.c:601 [inline]
 __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746
 hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458
 hfsplus_bmap_reserve+0x122/0x500 fs/hfsplus/btree.c:358
 __hfsplus_ext_write_extent+0x28d/0x5b0 fs/hfsplus/extents.c:104
 __hfsplus_ext_cache_extent+0x89/0xe30 fs/hfsplus/extents.c:186
 hfsplus_ext_read_extent fs/hfsplus/extents.c:218 [inline]
 hfsplus_file_extend+0x444/0x1990 fs/hfsplus/extents.c:462
 hfsplus_get_block+0x411/0x1530 fs/hfsplus/extents.c:245
 __block_write_begin_int+0x6b2/0x1900 fs/buffer.c:2151
 block_write_begin fs/buffer.c:2262 [inline]
 cont_write_begin+0x789/0xb50 fs/buffer.c:2601
 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46
 cont_expand_zero fs/buffer.c:2528 [inline]
 cont_write_begin+0x2fa/0xb50 fs/buffer.c:2591
 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46
 generic_cont_expand_simple+0x13f/0x210 fs/buffer.c:2492
 hfsplus_setattr+0x169/0x270 fs/hfsplus/inode.c:258
 notify_change+0xb33/0xe40 fs/attr.c:552
 do_truncate+0x1a4/0x220 fs/open.c:68
 vfs_truncate+0x493/0x520 fs/open.c:118
 do_sys_truncate+0xdb/0x190 fs/open.c:141
 __do_sys_truncate fs/open.c:153 [inline]
 __se_sys_truncate fs/open.c:151 [inline]
 __x64_sys_truncate+0x5b/0x70 fs/open.c:151
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f019af8e969
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:00007f019bd9a038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007f019b1b5fa0 RCX: 00007f019af8e969
RDX: 0000000000000000 RSI: 00000000001fefff RDI: 0000200000000280
RBP: 00007f019b010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f019b1b5fa0 R15: 00007ffe6e397118
 </TASK>