[v6.1] WARNING in hfsplus_unlink

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 50cbba13faa2 Linux 6.1.159
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12451792580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6a5cbd268406bf43
dashboard link: https://syzkaller.appspot.com/bug?extid=2f726e7146e76dde94b6
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/50ceb00b1b39/disk-50cbba13.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ebb8883b9a29/vmlinux-50cbba13.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7edc2a795f03/bzImage-50cbba13.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2f726e...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 8244 at fs/inode.c:332 drop_nlink+0xbb/0x100 fs/inode.c:332
Modules linked in:
CPU: 0 PID: 8244 Comm: syz.3.621 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:drop_nlink+0xbb/0x100 fs/inode.c:332
Code: 48 8b 1b 48 8d bb c0 07 00 00 be 08 00 00 00 e8 7b 78 eb ff f0 48 ff 83 c0 07 00 00 5b 41 5c 41 5e 41 5f 5d c3 e8 75 45 9b ff <0f> 0b eb 88 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 62 ff ff ff 4c
RSP: 0018:ffffc90004f67c10 EFLAGS: 00010283
RAX: ffffffff81e59a5b RBX: ffff88805860f470 RCX: 0000000000080000
RDX: ffffc9000f01b000 RSI: 000000000000580c RDI: 000000000000580d
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520009eceed
R10: fffff520009eceed R11: 1ffff920009eceec R12: 1ffff1100b0c1e97
R13: ffff888073db9ac8 R14: ffff88805860f4b8 R15: dffffc0000000000
FS: 00007f0e591626c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d6b2f06c8 CR3: 000000004df1a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
hfsplus_unlink+0x3c8/0x760 fs/hfsplus/dir.c:381
vfs_unlink+0x385/0x600 fs/namei.c:4330
do_unlinkat+0x324/0x560 fs/namei.c:4398
__do_sys_unlinkat fs/namei.c:4441 [inline]
__se_sys_unlinkat fs/namei.c:4434 [inline]
__x64_sys_unlinkat+0xd1/0xe0 fs/namei.c:4434
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0e5838f749
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:00007f0e59162038 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f0e585e5fa0 RCX: 00007f0e5838f749
RDX: 0000000000000000 RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f0e58413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0e585e6038 R14: 00007f0e585e5fa0 R15: 00007ffe2bd0aab8
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 50cbba13faa2 Linux 6.1.159
git tree: linux-6.1.y

console output: https://syzkaller.appspot.com/x/log.txt?x=12a42422580000

kernel config: https://syzkaller.appspot.com/x/.config?x=6a5cbd268406bf43
dashboard link: https://syzkaller.appspot.com/bug?extid=2f726e7146e76dde94b6
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=119d1792580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10c2549a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/50ceb00b1b39/disk-50cbba13.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ebb8883b9a29/vmlinux-50cbba13.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7edc2a795f03/bzImage-50cbba13.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/3f37309b6845/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2f726e...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 1024
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4436 at fs/inode.c:332 drop_nlink+0xbb/0x100 fs/inode.c:332
Modules linked in:
CPU: 1 PID: 4436 Comm: syz.0.17 Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:drop_nlink+0xbb/0x100 fs/inode.c:332
Code: 48 8b 1b 48 8d bb c0 07 00 00 be 08 00 00 00 e8 7b 78 eb ff f0 48 ff 83 c0 07 00 00 5b 41 5c 41 5e 41 5f 5d c3 e8 75 45 9b ff <0f> 0b eb 88 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 62 ff ff ff 4c

RSP: 0018:ffffc900035d7c10 EFLAGS: 00010293
RAX: ffffffff81e59a5b RBX: ffff888030642a30 RCX: ffff888079f8d940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520006baeed
R10: fffff520006baeed R11: 1ffff920006baeec R12: 1ffff110060c854f
R13: ffff88806f77e7b0 R14: ffff888030642a78 R15: dffffc0000000000
FS: 000055556128c500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000001b2d863fff CR3: 0000000023f17000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
hfsplus_unlink+0x3c8/0x760 fs/hfsplus/dir.c:381
vfs_unlink+0x385/0x600 fs/namei.c:4330
do_unlinkat+0x324/0x560 fs/namei.c:4398
__do_sys_unlinkat fs/namei.c:4441 [inline]
__se_sys_unlinkat fs/namei.c:4434 [inline]
__x64_sys_unlinkat+0xd1/0xe0 fs/namei.c:4434
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

RIP: 0033:0x7f5ab818f749

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:00007fff48a12f18 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f5ab83e5fa0 RCX: 00007f5ab818f749

RDX: 0000000000000000 RSI: 0000200000000000 RDI: ffffffffffffff9c

RBP: 00007f5ab8213f91 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 00007f5ab83e5fa0 R14: 00007f5ab83e5fa0 R15: 0000000000000003
</TASK>


---
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