[moderation] [fs?] WARNING in vfs_remove_acl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 262858079afd Add linux-next specific files for 20250926
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=14b4df12580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6117d7eea7e1f3a7
dashboard link: https://syzkaller.appspot.com/bug?extid=21d97b2756618e83ee2e
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/818c8ba6ac53/disk-26285807.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/da143e1d7f10/vmlinux-26285807.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b73ae95dc148/bzImage-26285807.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+21d97b...@syzkaller.appspotmail.com

------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff888038c65d98, owner = 0x0, curr 0xffff88807cdb3c80, list empty
WARNING: kernel/locking/rwsem.c:1381 at __up_write kernel/locking/rwsem.c:1380 [inline], CPU#1: syz.3.5843/29978
WARNING: kernel/locking/rwsem.c:1381 at up_write+0x3a2/0x420 kernel/locking/rwsem.c:1643, CPU#1: syz.3.5843/29978
Modules linked in:
CPU: 1 UID: 0 PID: 29978 Comm: syz.3.5843 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__up_write kernel/locking/rwsem.c:1380 [inline]
RIP: 0010:up_write+0x3a2/0x420 kernel/locking/rwsem.c:1643
Code: d0 48 c7 c7 80 ff aa 8b 48 c7 c6 a0 01 ab 8b 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 83 36 e6 ff 48 83 c4 08 90 <0f> 0b 90 90 e9 6d fd ff ff 48 c7 c1 74 87 c3 8f 80 e1 07 80 c1 03
RSP: 0018:ffffc90003c3fbf8 EFLAGS: 00010282
RAX: 2af0e8e65db80f00 RBX: ffff888038c65d98 RCX: ffff88807cdb3c80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1c3a65c R12: 0000000000000000
R13: ffff888038c65df0 R14: ffff888038c65d98 R15: 1ffff1100718cbb4
FS: 00007f56a0eec6c0(0000) GS:ffff888125afc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000030000 CR3: 000000007bd72000 CR4: 00000000003526f0
Call Trace:
<TASK>
inode_unlock include/linux/fs.h:990 [inline]
vfs_remove_acl+0x67a/0x700 fs/posix_acl.c:1250
removexattr fs/xattr.c:1022 [inline]
filename_removexattr fs/xattr.c:1052 [inline]
path_removexattrat+0x49a/0x690 fs/xattr.c:1088
__do_sys_removexattr fs/xattr.c:1100 [inline]
__se_sys_removexattr fs/xattr.c:1097 [inline]
__x64_sys_removexattr+0x62/0x70 fs/xattr.c:1097
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f569ff8eec9
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:00007f56a0eec038 EFLAGS: 00000246 ORIG_RAX: 00000000000000c5
RAX: ffffffffffffffda RBX: 00007f56a01e6090 RCX: 00007f569ff8eec9
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 00002000000003c0
RBP: 00007f56a0011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56a01e6128 R14: 00007f56a01e6090 R15: 00007ffe9cd39538
</TASK>


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