hfs: new node 0 already hashed?
------------[ cut here ]------------
WARNING: CPU: 0 PID: 19393 at fs/hfs/bnode.c:520 hfs_bnode_create+0x3b9/0x440 fs/hfs/bnode.c:519
Modules linked in:
CPU: 0 PID: 19393 Comm: kworker/u4:1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:hfs_bnode_create+0x3b9/0x440 fs/hfs/bnode.c:520
Code: d4 e0 8a 89 ee e8 47 8c 1f 08 e9 73 fd ff ff e8 1d 1c 2d ff 4c 89 ef e8 45 bc 34 08 48 c7 c7 c0 d4 e0 8a 89 ee e8 27 8c 1f 08 <0f> 0b eb b7 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 7f fc ff ff 4c
RSP: 0018:ffffc9001b666e18 EFLAGS: 00010246
RAX: 000000000000001f RBX: ffff88802f544000 RCX: ebc864ad61e32300
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffc9001b666b27 R09: 1ffff920036ccd64
R10: dffffc0000000000 R11: fffff520036ccd65 R12: 0000000000000000
R13: ffff88802f5440e0 R14: ffff888019a72b00 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f821ff8 CR3: 0000000060d33000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 hfs_bmap_alloc+0x541/0x5d0 fs/hfs/btree.c:326
 hfs_btree_inc_height+0x101/0xac0 fs/hfs/brec.c:490
 hfs_brec_insert+0x748/0xbd0 fs/hfs/brec.c:148
 __hfs_ext_write_extent+0x2a1/0x470 fs/hfs/extent.c:124
 hfs_ext_write_extent+0x17f/0x210 fs/hfs/extent.c:144
 hfs_write_inode+0xdc/0x880 fs/hfs/inode.c:434
 write_inode fs/fs-writeback.c:1483 [inline]
 __writeback_single_inode+0x705/0xec0 fs/fs-writeback.c:1700
 writeback_sb_inodes+0x7cd/0xf50 fs/fs-writeback.c:1926
 wb_writeback+0x46a/0xbf0 fs/fs-writeback.c:2105
 wb_do_writeback fs/fs-writeback.c:2252 [inline]
 wb_workfn+0x400/0xe60 fs/fs-writeback.c:2292
 process_one_work kernel/workqueue.c:2653 [inline]
 process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>