[v6.6] WARNING in minix_rmdir

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 5fa4793a2d2d Linux 6.6.119
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1292849a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=691a6769a86ac817
dashboard link: https://syzkaller.appspot.com/bug?extid=ad0c1f4d763cfeb7f15c
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/63699875f1dd/disk-5fa4793a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8506652fcb6f/vmlinux-5fa4793a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1b30ceed1710/bzImage-5fa4793a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ad0c1f...@syzkaller.appspotmail.com

minix_free_inode: bit 5 already cleared
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5769 at fs/inode.c:332 drop_nlink+0xbf/0x100 fs/inode.c:332
Modules linked in:
CPU: 0 PID: 5769 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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 e7 48 ea ff f0 48 ff 83 78 07 00 00 5b 41 5c 41 5e 41 5f 5d c3 e8 01 d9 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:ffffc9000450fcb0 EFLAGS: 00010293
RAX: ffffffff81f2b7bf RBX: ffff88805b9a9ad0 RCX: ffff8880297dbc00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8e4a212f R09: 1ffffffff1c94425
R10: dffffc0000000000 R11: fffffbfff1c94426 R12: 1ffff1100b735365
R13: ffff88805b9a9580 R14: ffff88805b9a9b28 R15: dffffc0000000000
FS: 0000555574fb1500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555574fe4688 CR3: 0000000061624000 CR4: 00000000003526f0
Call Trace:
<TASK>
inode_dec_link_count include/linux/fs.h:2340 [inline]
minix_rmdir+0x225/0x280 fs/minix/namei.c:171
vfs_rmdir+0x370/0x4d0 fs/namei.c:4204
do_rmdir+0x29e/0x5c0 fs/namei.c:4263
__do_sys_unlinkat fs/namei.c:4441 [inline]
__se_sys_unlinkat fs/namei.c:4435 [inline]
__x64_sys_unlinkat+0xc4/0xe0 fs/namei.c:4435
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: 0033:0x7f135938ed27
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 07 01 00 00 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:00007ffc28d3fcb8 EFLAGS: 00000207 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f135938ed27
RDX: 0000000000000200 RSI: 00007ffc28d40e60 RDI: 00000000ffffff9c
RBP: 00007f1359413d7d R08: 0000555574fdc6ab R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000207 R12: 00007ffc28d40e60
R13: 00007f1359413d7d R14: 0000000000028adc R15: 00007ffc28d43020
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 5fa4793a2d2d Linux 6.6.119
git tree: linux-6.6.y

console output: https://syzkaller.appspot.com/x/log.txt?x=172c3022580000

kernel config: https://syzkaller.appspot.com/x/.config?x=691a6769a86ac817
dashboard link: https://syzkaller.appspot.com/bug?extid=ad0c1f4d763cfeb7f15c
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=1012489a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15715bb4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/63699875f1dd/disk-5fa4793a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8506652fcb6f/vmlinux-5fa4793a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1b30ceed1710/bzImage-5fa4793a.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/bb0ed94f781f/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=14e25b92580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ad0c1f...@syzkaller.appspotmail.com

minix_free_inode: bit 5 already cleared
------------[ cut here ]------------

WARNING: CPU: 0 PID: 5871 at fs/inode.c:332 drop_nlink+0xbf/0x100 fs/inode.c:332
Modules linked in:
CPU: 0 PID: 5871 Comm: syz-executor Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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 e7 48 ea ff f0 48 ff 83 78 07 00 00 5b 41 5c 41 5e 41 5f 5d c3 e8 01 d9 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:ffffc90002e67cb0 EFLAGS: 00010293
RAX: ffffffff81f2b7bf RBX: ffff88805f178590 RCX: ffff888028f3da00

RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8e4a212f R09: 1ffffffff1c94425

R10: dffffc0000000000 R11: fffffbfff1c94426 R12: 1ffff1100be2f0bd
R13: ffff88805f178040 R14: ffff88805f1785e8 R15: dffffc0000000000
FS: 000055558ff6e500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000

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

CR2: 000055558ff91608 CR3: 000000002e7cc000 CR4: 00000000003506f0

Call Trace:
<TASK>
inode_dec_link_count include/linux/fs.h:2340 [inline]
minix_rmdir+0x225/0x280 fs/minix/namei.c:171
vfs_rmdir+0x370/0x4d0 fs/namei.c:4204
do_rmdir+0x29e/0x5c0 fs/namei.c:4263
__do_sys_unlinkat fs/namei.c:4441 [inline]
__se_sys_unlinkat fs/namei.c:4435 [inline]
__x64_sys_unlinkat+0xc4/0xe0 fs/namei.c:4435
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: 0033:0x7f812598ed27

Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 07 01 00 00 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:00007ffec9ebfc78 EFLAGS: 00000207 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f812598ed27
RDX: 0000000000000200 RSI: 00007ffec9ec0e20 RDI: 00000000ffffff9c
RBP: 00007f8125a13d7d R08: 000055558ff996ab R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000207 R12: 00007ffec9ec0e20
R13: 00007f8125a13d7d R14: 00000000000128c9 R15: 00007ffec9ec2fe0
</TASK>


---
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