[v6.6] WARNING in minix_rename

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 0a805b6ea8cd Linux 6.6.116
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11b7fc12580000
kernel config: https://syzkaller.appspot.com/x/.config?x=12606d4b8832c7e4
dashboard link: https://syzkaller.appspot.com/bug?extid=a2fe2e6bff316d3915fa
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=1533960a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17430658580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/13874446b4b2/disk-0a805b6e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/69a5e59e1ade/vmlinux-0a805b6e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/322c0711f976/bzImage-0a805b6e.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/b7f2b7ab5ad5/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=1133960a580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a2fe2e...@syzkaller.appspotmail.com

loop9: detected capacity change from 0 to 64
MINIX-fs: mounting unchecked file system, running fsck is recommended
------------[ cut here ]------------
WARNING: CPU: 1 PID: 7658 at fs/inode.c:332 drop_nlink+0xbf/0x100 fs/inode.c:332
Modules linked in:
CPU: 1 PID: 7658 Comm: syz.9.99 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:drop_nlink+0xbf/0x100 fs/inode.c:332
Code: 48 8b 1b 48 8d bb 78 07 00 00 be 08 00 00 00 e8 57 58 ea ff f0 48 ff 83 78 07 00 00 5b 41 5c 41 5e 41 5f 5d c3 e8 11 fb 92 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:ffffc9000543fa90 EFLAGS: 00010293
RAX: ffffffff81f2947f RBX: ffff88805d645030 RCX: ffff88802abc3c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88802abc3c00 R09: 0000000000000002
R10: 000000003b9aca00 R11: 0000000000000000 R12: 1ffff1100bac8a11
R13: ffff88805d645030 R14: ffff88805d645088 R15: dffffc0000000000
FS: 00007f69293cc6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001980 CR3: 00000000617af000 CR4: 00000000003506e0
Call Trace:
<TASK>
inode_dec_link_count include/linux/fs.h:2340 [inline]
minix_rename+0x331/0x4a0 fs/minix/namei.c:224
vfs_rename+0xb96/0xec0 fs/namei.c:4880
do_renameat2+0x8a1/0xc70 fs/namei.c:5033
__do_sys_rename fs/namei.c:5079 [inline]
__se_sys_rename fs/namei.c:5077 [inline]
__x64_sys_rename+0x86/0x90 fs/namei.c:5077
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f692858f6c9
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:00007f69293cc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f69287e5fa0 RCX: 00007f692858f6c9
RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000200000001980
RBP: 00007f6928611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f69287e6038 R14: 00007f69287e5fa0 R15: 00007ffc9ef7fd78
</TASK>


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