[v6.6] kernel BUG in ocfs2_truncate_log_needs_flush

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 924b4a879cbb Linux 6.6.142
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14350bd2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=90249d2d52c08134
dashboard link: https://syzkaller.appspot.com/bug?extid=edaf0f370858d1ad746a
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14a7c3b6580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=156704ae580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bd13425862f1/disk-924b4a87.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/eaa5de9e440b/vmlinux-924b4a87.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5a9aa3293c15/bzImage-924b4a87.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/2fd48fb17e90/mount_0.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=15302986580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+edaf0f...@syzkaller.appspotmail.com

option from the mount to silence this warning.
=======================================================
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
(syz.0.17,5938,1):ocfs2_truncate_log_needs_flush:5822 ERROR: bug expression: le16_to_cpu(tl->tl_used) > le16_to_cpu(tl->tl_count)
(syz.0.17,5938,1):ocfs2_truncate_log_needs_flush:5822 ERROR: slot 0, invalid truncate log parameters: used = 128, count = 39
------------[ cut here ]------------
kernel BUG at fs/ocfs2/alloc.c:5822!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 5938 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:ocfs2_truncate_log_needs_flush+0x300/0x310 fs/ocfs2/alloc.c:5819
Code: c7 c1 a0 90 09 8b 45 89 e8 45 89 f9 50 e8 c8 de 1d 00 48 83 c4 08 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 10 c6 44 01 08 f8 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 f3 0f 1e fa 55 48
RSP: 0018:ffffc90003397660 EFLAGS: 00010296
RAX: dffffc0000000000 RBX: 1ffff1100bdc4958 RCX: 1ffff92000672ed0
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90003397730 R08: ffffc90003397207 R09: 1ffff92000672e40
R10: dffffc0000000000 R11: fffff52000672e41 R12: ffffc900033976c0
R13: 0000000000000000 R14: 1ffff1100bdc4958 R15: 0000000000000080
FS: 0000555573e54500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9147a1a000 CR3: 0000000073cb2000 CR4: 00000000003506e0
Call Trace:
<TASK>
ocfs2_xattr_set+0xbb1/0x13e0 fs/ocfs2/xattr.c:3624
__vfs_setxattr+0x431/0x470 fs/xattr.c:201
__vfs_setxattr_noperm+0x12d/0x5e0 fs/xattr.c:235
vfs_setxattr+0x16b/0x2f0 fs/xattr.c:322
do_setxattr fs/xattr.c:630 [inline]
path_setxattr+0x3f3/0x5d0 fs/xattr.c:659
__do_sys_setxattr fs/xattr.c:677 [inline]
__se_sys_setxattr fs/xattr.c:673 [inline]
__x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:673
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f72fe19ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc977b4338 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f72fe415fa0 RCX: 00007f72fe19ce59
RDX: 0000200000001400 RSI: 0000200000000240 RDI: 00002000000001c0
RBP: 00007f72fe232d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000841 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f72fe415fac R14: 00007f72fe415fa0 R15: 00007f72fe415fa0
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_truncate_log_needs_flush+0x300/0x310 fs/ocfs2/alloc.c:5819
Code: c7 c1 a0 90 09 8b 45 89 e8 45 89 f9 50 e8 c8 de 1d 00 48 83 c4 08 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 10 c6 44 01 08 f8 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 f3 0f 1e fa 55 48
RSP: 0018:ffffc90003397660 EFLAGS: 00010296
RAX: dffffc0000000000 RBX: 1ffff1100bdc4958 RCX: 1ffff92000672ed0
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90003397730 R08: ffffc90003397207 R09: 1ffff92000672e40
R10: dffffc0000000000 R11: fffff52000672e41 R12: ffffc900033976c0
R13: 0000000000000000 R14: 1ffff1100bdc4958 R15: 0000000000000080
FS: 0000555573e54500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9147a1a000 CR3: 0000000073cb2000 CR4: 00000000003506e0


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