hfsplus: new node 0 already hashed?
------------[ cut here ]------------
WARNING: fs/hfsplus/bnode.c:631 at hfsplus_bnode_create+0x461/0x4f0 fs/hfsplus/bnode.c:631, CPU#1: syz.1.18/6018
Modules linked in:
CPU: 1 UID: 0 PID: 6018 Comm: syz.1.18 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:hfsplus_bnode_create+0x461/0x4f0 fs/hfsplus/bnode.c:631
Code: a2 8b 89 ee e8 70 d3 83 fe e9 cf fc ff ff e8 56 5e 1e ff 4c 89 ef e8 8e b1 d7 08 48 c7 c7 c0 94 a2 8b 89 ee e8 50 d3 83 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:ffffc90004197500 EFLAGS: 00010246
RAX: 0000000000000023 RBX: ffff88816e2f2000 RCX: 79c13499d9df3d00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffc90004197287 R09: 1ffff92000832e50
R10: dffffc0000000000 R11: fffff52000832e51 R12: 0000000000000000
R13: ffff88816e2f20e0 R14: ffff88816d39a800 R15: dffffc0000000000
FS:  00007f02ed01d6c0(0000) GS:ffff8882a99f4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa8bce17dac CR3: 00000001a366c000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 hfsplus_bmap_alloc+0x747/0xb00 fs/hfsplus/btree.c:421
 hfs_bnode_split+0xd4/0x1090 fs/hfsplus/brec.c:245
 hfsplus_brec_insert+0x3bc/0xd70 fs/hfsplus/brec.c:100
 hfsplus_create_cat+0x426/0x11b0 fs/hfsplus/catalog.c:292
 hfsplus_mknod+0x16a/0x290 fs/hfsplus/dir.c:494
 vfs_create+0x2d1/0x460 fs/namei.c:4139
 do_mknodat+0x3f1/0x680 fs/namei.c:5112
 __do_sys_mknod fs/namei.c:5149 [inline]
 __se_sys_mknod fs/namei.c:5147 [inline]
 __x64_sys_mknod+0x8c/0xa0 fs/namei.c:5147
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f02ec19acb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f02ed01d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f02ec415fa0 RCX: 00007f02ec19acb9
RDX: 0000000000000703 RSI: 0000000000000000 RDI: 0000200000000000
RBP: 00007f02ec208bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f02ec416038 R14: 00007f02ec415fa0 R15: 00007ffccdbe5dc8
 </TASK>
