[moderation] [fs?] WARNING in chmod_common (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 66701750d556 Merge tag 'io_uring-6.16-20250630' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1514b982580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b2b65db779ece75e
dashboard link: https://syzkaller.appspot.com/bug?extid=0f4421321ddbe8f9d4b3
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
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 (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-66701750.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1d8f66edfc3c/vmlinux-66701750.xz
kernel image: https://storage.googleapis.com/syzbot-assets/88b42e24ecd7/bzImage-66701750.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0f4421...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
gfs2: fsid=syz:syz: Trying to join cluster "lock_nolock", "syz:syz"
gfs2: fsid=syz:syz: Now mounting FS (format 1801)...
gfs2: fsid=syz:syz.0: journal 0 mapped with 3 extents in 0ms
gfs2: fsid=syz:syz.0: first mount done, others may mount
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x1, magic = 0xffff8880524f14e8, owner = 0xffff88801c77c880, curr 0xffff888000c78000, list empty
WARNING: CPU: 0 PID: 5332 at kernel/locking/rwsem.c:1368 __up_write kernel/locking/rwsem.c:1367 [inline]
WARNING: CPU: 0 PID: 5332 at kernel/locking/rwsem.c:1368 up_write+0x3a2/0x420 kernel/locking/rwsem.c:1630
Modules linked in:
CPU: 0 UID: 0 PID: 5332 Comm: syz.0.0 Not tainted 6.16.0-rc4-syzkaller-00013-g66701750d556 #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__up_write kernel/locking/rwsem.c:1367 [inline]
RIP: 0010:up_write+0x3a2/0x420 kernel/locking/rwsem.c:1630
Code: d0 48 c7 c7 40 f1 8a 8b 48 c7 c6 60 f3 8a 8b 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 b3 3b e6 ff 48 83 c4 08 90 <0f> 0b 90 90 e9 6d fd ff ff 48 c7 c1 34 36 a1 8f 80 e1 07 80 c1 03
RSP: 0018:ffffc9000d577c50 EFLAGS: 00010296
RAX: 29c7c66463697400 RBX: ffff8880524f14e8 RCX: ffff888000c78000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfa9fc R12: ffff88801c77c880
R13: ffff8880524f1540 R14: ffff8880524f14e8 R15: 1ffff1100a49e29e
FS: 00007fec54e206c0(0000) GS:ffff88808d250000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fec54dddfc8 CR3: 0000000043c13000 CR4: 0000000000352ef0
Call Trace:
<TASK>
inode_unlock include/linux/fs.h:879 [inline]
chmod_common+0x253/0x400 fs/open.c:652
do_fchmodat+0x12d/0x200 fs/open.c:696
__do_sys_chmod fs/open.c:720 [inline]
__se_sys_chmod fs/open.c:718 [inline]
__x64_sys_chmod+0x62/0x70 fs/open.c:718
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: 0033:0x7fec53f8e929
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:00007fec54e20038 EFLAGS: 00000246 ORIG_RAX: 000000000000005a
RAX: ffffffffffffffda RBX: 00007fec541b5fa0 RCX: 00007fec53f8e929
RDX: 0000000000000000 RSI: 0000000000000300 RDI: 0000200000000000
RBP: 00007fec54010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fec541b5fa0 R15: 00007fff97619728
</TASK>


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.