hfs: new node 0 already hashed?
------------[ cut here ]------------
WARNING: fs/hfs/bnode.c:520 at hfs_bnode_create+0x461/0x4f0 fs/hfs/bnode.c:520, CPU#0: syz.8.645/9095
Modules linked in:
CPU: 0 UID: 0 PID: 9095 Comm: syz.8.645 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:hfs_bnode_create+0x461/0x4f0 fs/hfs/bnode.c:520
Code: 82 8b 89 ee e8 50 44 87 fe e9 cf fc ff ff e8 46 3b 20 ff 4c 89 ef e8 0e 90 b7 08 48 c7 c7 60 4a 82 8b 89 ee e8 30 44 87 fe 90 <0f> 0b 90 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c d6 fb ff ff
RSP: 0018:ffffc9000bd7ee20 EFLAGS: 00010246
RAX: 000000000000001f RBX: ffff88807ab76000 RCX: dfabdea5a210f400
RDX: ffffc9000bf99000 RSI: 000000000002537a RDI: 000000000002537b
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bba6f0 R12: 0000000000000000
R13: ffff88807ab760e0 R14: ffff88805777a600 R15: dffffc0000000000
FS:  00007fb446e026c0(0000) GS:ffff888125ee2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000032000 CR3: 000000002823e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 hfs_bmap_alloc+0x5bb/0x640 fs/hfs/btree.c:326
 hfs_btree_inc_height+0xf6/0xac0 fs/hfs/brec.c:490
 hfs_brec_insert+0x7ee/0xc80 fs/hfs/brec.c:148
 __hfs_ext_write_extent+0x2a1/0x470 fs/hfs/extent.c:124
 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x31e/0x1540 fs/hfs/extent.c:401
 hfs_get_block+0x3d7/0xbd0 fs/hfs/extent.c:353
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
 block_write_begin fs/buffer.c:2256 [inline]
 cont_write_begin+0x78c/0xb50 fs/buffer.c:2594
 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4313
 generic_file_write_iter+0x117/0x550 mm/filemap.c:4456
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c9/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb445f8efc9
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:00007fb446e02038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fb4461e5fa0 RCX: 00007fb445f8efc9
RDX: 00000000000101bf RSI: 0000200000000380 RDI: 0000000000000004
RBP: 00007fb446011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb4461e6038 R14: 00007fb4461e5fa0 R15: 00007ffff53451c8
 </TASK>