[moderation] [fs?] WARNING in minix_rename

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c72692105976 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=15a174cc580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7731aa6ae1d31c0a
dashboard link: https://syzkaller.appspot.com/bug?extid=435dfcadc12d475821b3
compiler: Debian clang version 15.0.6, Debian LLD 15.0.6
userspace arch: arm64
CC: [linux-...@vger.kernel.org linux-...@vger.kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/85f7b40b588b/disk-c7269210.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/034a39113dc5/vmlinux-c7269210.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d0a0b73be5c2/Image-c7269210.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+435dfc...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 6601 at fs/inode.c:417 drop_nlink+0xe4/0x138 fs/inode.c:417
Modules linked in:
CPU: 1 UID: 0 PID: 6601 Comm: syz.1.2 Not tainted 6.15.0-rc2-syzkaller-gc72692105976 #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : drop_nlink+0xe4/0x138 fs/inode.c:417
lr : drop_nlink+0xe4/0x138 fs/inode.c:417
sp : ffff8000a2c07740
x29: ffff8000a2c07740 x28: ffff700014580ef8 x27: ffff0000f0f0daa8
x26: fffffdffc3cf3ef4 x25: 1ffff00014580f00 x24: dfff800000000000
x23: 1fffe0001e1e1b5e x22: dfff800000000000 x21: 0000000000000000
x20: ffff0000f0f0daf0 x19: ffff0000f0f0daa8 x18: 1fffe000366e26b6
x17: ffff80008ff2e000 x16: ffff80008333712c x15: 0000000000000001
x14: 1ffff00012f72ba0 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000080000 x10: 000000000002218d x9 : ffff8000abe84000
x8 : 000000000002218e x7 : ffff8000805a60b0 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff8000805a60bc
x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
drop_nlink+0xe4/0x138 fs/inode.c:417 (P)
inode_dec_link_count include/linux/fs.h:2581 [inline]
minix_rename+0x3d0/0x774 fs/minix/namei.c:222
vfs_rename+0x9bc/0xc84 fs/namei.c:5086
do_renameat2+0x948/0xd94 fs/namei.c:5235
__do_sys_renameat2 fs/namei.c:5269 [inline]
__se_sys_renameat2 fs/namei.c:5266 [inline]
__arm64_sys_renameat2+0xd8/0xf4 fs/namei.c:5266
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
irq event stamp: 2822
hardirqs last enabled at (2821): [<ffff80008059ff20>] seqcount_lockdep_reader_access+0x80/0x104 include/linux/seqlock.h:74
hardirqs last disabled at (2822): [<ffff80008b985884>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:488
softirqs last enabled at (280): [<ffff80008012c108>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (278): [<ffff80008012c0d4>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 78f4e737a53e Merge tag 'for-6.16/dm-fixes' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10b29182580000
kernel config: https://syzkaller.appspot.com/x/.config?x=28cc6f051378bb16
dashboard link: https://syzkaller.appspot.com/bug?extid=435dfcadc12d475821b3
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1446370c580000
CC: [linux-...@vger.kernel.org linux-...@vger.kernel.org]

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/560a423a60ad/disk-78f4e737.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9e97e18d85b9/vmlinux-78f4e737.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a147a5a27c6e/bzImage-78f4e737.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/2c4c332ed1d0/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=12276b70580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+435dfc...@syzkaller.appspotmail.com

------------[ cut here ]------------

WARNING: CPU: 0 PID: 6388 at fs/inode.c:417 drop_nlink+0xc5/0x110 fs/inode.c:417
Modules linked in:
CPU: 0 UID: 0 PID: 6388 Comm: syz.6.27 Not tainted 6.16.0-rc3-syzkaller-00042-g78f4e737a53e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:drop_nlink+0xc5/0x110 fs/inode.c:417
Code: 78 07 00 00 be 08 00 00 00 e8 c7 35 e8 ff f0 48 ff 83 78 07 00 00 5b 41 5c 41 5e 41 5f 5d e9 42 01 29 09 cc e8 fc da 86 ff 90 <0f> 0b 90 eb 81 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 5b ff ff ff
RSP: 0018:ffffc900030c7a30 EFLAGS: 00010293
RAX: ffffffff82397124 RBX: ffff888055405aa8 RCX: ffff88802da29e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8f9fe1f7 R09: 1ffffffff1f3fc3e
R10: dffffc0000000000 R11: fffffbfff1f3fc3f R12: 1ffff1100aa80b5e
R13: 0000000000000000 R14: ffff888055405af0 R15: dffffc0000000000
FS: 00007fb57180a6c0(0000) GS:ffff888125c83000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb571809f98 CR3: 0000000032278000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
inode_dec_link_count include/linux/fs.h:2634 [inline]
minix_rename+0x3cf/0x700 fs/minix/namei.c:222
vfs_rename+0xb99/0xec0 fs/namei.c:5137
do_renameat2+0x878/0xc50 fs/namei.c:5286
__do_sys_rename fs/namei.c:5333 [inline]
__se_sys_rename fs/namei.c:5331 [inline]
__x64_sys_rename+0x82/0x90 fs/namei.c:5331
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb57098e929
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:00007fb57180a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007fb570bb6080 RCX: 00007fb57098e929
RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000200000001980
RBP: 00007fb570a10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fb570bb6080 R15: 00007fffa5abc5a8
</TASK>


---
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[syzbot]

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