[syzbot] [gfs2?] kernel BUG in do_qc

[syzbot <syzbot+bad65435361712796381@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    e0797d3b91de Merge tag 'fs_for_v6.16-rc1' of git://git.ker..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15906482580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d8dc7eba91909b25
dashboard link: https://syzkaller.appspot.com/bug?extid=bad65435361712796381
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9c217b1391c8/disk-e0797d3b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/610d0945fbb8/vmlinux-e0797d3b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/873bcc0b4e15/bzImage-e0797d3b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bad65435361712796381@syzkaller.appspotmail.com

gfs2: fsid=syz:syz.0: fatal assertion failed
------------[ cut here ]------------
kernel BUG at fs/gfs2/quota.c:320!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 1 UID: 0 PID: 15470 Comm: syz.7.1727 Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__qd_hold fs/gfs2/quota.c:320 [inline]
RIP: 0010:do_qc+0x5c1/0x5e0 fs/gfs2/quota.c:705
Code: 00 00 00 00 00 fc ff df 48 8b 0c 24 80 3c 01 00 74 0a 48 8b 7c 24 10 e8 ed ac 2d fe 48 8b 44 24 10 48 8b 38 e8 00 9a 34 fd 90 <0f> 0b e8 38 8f ca fd 48 8b 7c 24 10 e8 ee 99 34 fd 90 0f 0b 66 66
RSP: 0018:ffffc90004897870 EFLAGS: 00010246
RAX: 000000000000002c RBX: 1ffff1100fcd880e RCX: 6b8263604adfeb00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffffffffffff R08: ffffc90004897547 R09: 1ffff92000912ea8
R10: dffffc0000000000 R11: fffff52000912ea9 R12: ffff88807e6c4000
R13: ffff88807e6c4070 R14: ffff88807e6c4090 R15: 0000000000000000
FS:  00005555633cd500(0000) GS:ffff888125d64000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1ec997ed38 CR3: 000000005be83000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 gfs2_quota_change+0x394/0x800 fs/gfs2/quota.c:1304
 gfs2_free_di+0x2db/0x3f0 fs/gfs2/rgrp.c:2592
 gfs2_dinode_dealloc+0x30d/0x3e0 fs/gfs2/inode.c:497
 evict_unlinked_inode fs/gfs2/super.c:1332 [inline]
 gfs2_evict_inode+0xe0b/0x1000 fs/gfs2/super.c:1429
 evict+0x504/0x9c0 fs/inode.c:810
 __dentry_kill+0x209/0x660 fs/dcache.c:669
 dput+0x19f/0x2b0 fs/dcache.c:911
 __fput+0x68e/0xa70 fs/file_table.c:473
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff80c58e969
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:00007ffdc7ba0008 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000015531b RCX: 00007ff80c58e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007ff80c7b7ba0 R08: 0000000000000001 R09: 0000000dc7ba02ff
R10: 00007ff80c400000 R11: 0000000000000246 R12: 00007ff80c7b5fac
R13: 00007ff80c7b5fa0 R14: ffffffffffffffff R15: 00007ffdc7ba0120
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__qd_hold fs/gfs2/quota.c:320 [inline]
RIP: 0010:do_qc+0x5c1/0x5e0 fs/gfs2/quota.c:705
Code: 00 00 00 00 00 fc ff df 48 8b 0c 24 80 3c 01 00 74 0a 48 8b 7c 24 10 e8 ed ac 2d fe 48 8b 44 24 10 48 8b 38 e8 00 9a 34 fd 90 <0f> 0b e8 38 8f ca fd 48 8b 7c 24 10 e8 ee 99 34 fd 90 0f 0b 66 66
RSP: 0018:ffffc90004897870 EFLAGS: 00010246
RAX: 000000000000002c RBX: 1ffff1100fcd880e RCX: 6b8263604adfeb00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffffffffffff R08: ffffc90004897547 R09: 1ffff92000912ea8
R10: dffffc0000000000 R11: fffff52000912ea9 R12: ffff88807e6c4000
R13: ffff88807e6c4070 R14: ffff88807e6c4090 R15: 0000000000000000
FS:  00005555633cd500(0000) GS:ffff888125d64000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1ec997ed38 CR3: 000000005be83000 CR4: 0000000000350ef0


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