[v5.15] kernel BUG in ocfs2_truncate_log_needs_flush

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 98f47d0e9b8c Linux 5.15.184
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12d2a8e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9eb2b5a65dfc4761
dashboard link: https://syzkaller.appspot.com/bug?extid=8f07b58ba4e54c9eecea
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d2845fb3af6c/disk-98f47d0e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1f12b743be24/vmlinux-98f47d0e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8f178b57ea38/Image-98f47d0e.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8f07b5...@syzkaller.appspotmail.com

(syz.0.392,6124,1):ocfs2_truncate_log_needs_flush:5823 ERROR: bug expression: le16_to_cpu(tl->tl_used) > le16_to_cpu(tl->tl_count)
(syz.0.392,6124,1):ocfs2_truncate_log_needs_flush:5823 ERROR: slot 0, invalid truncate log parameters: used = 65535, count = 64295
------------[ cut here ]------------
kernel BUG at fs/ocfs2/alloc.c:5823!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 6124 Comm: syz.0.392 Not tainted 5.15.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : ocfs2_truncate_log_needs_flush+0x268/0x26c fs/ocfs2/alloc.c:5820
lr : ocfs2_truncate_log_needs_flush+0x268/0x26c fs/ocfs2/alloc.c:5820
sp : ffff80001f727420
x29: ffff80001f7274a0 x28: 1fffe0001c07c958 x27: 1fffe0001c07c958
x26: ffff700003ee4e84 x25: dfff800000000000 x24: ffff80001f727420
x23: 000000000000fb27 x22: 1000000000000000 x21: 000000000000ffff
x20: 0000000000000000 x19: ffff0000e03e4ac0 x18: 0000000000000002
x17: 0000000040000000 x16: ffff8000111a5644 x15: 0000000000000002
x14: 0000000000ff0100 x13: 1ffff0000282a06b x12: 0000000000080000
x11: 000000000000c54b x10: ffff800020a5b000 x9 : 8b4092ebe5fd5400
x8 : 8b4092ebe5fd5400 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000000 x3 : ffff80000a732644
x2 : ffff0001a111cd10 x1 : 0000000100000000 x0 : 0000000000000082
Call trace:
ocfs2_truncate_log_needs_flush+0x268/0x26c fs/ocfs2/alloc.c:5820
ocfs2_xattr_set+0x8b4/0xea8 fs/ocfs2/xattr.c:3628
ocfs2_xattr_trusted_set+0x4c/0x64 fs/ocfs2/xattr.c:7349
__vfs_setxattr+0x388/0x3a4 fs/xattr.c:182
__vfs_setxattr_noperm+0x120/0x564 fs/xattr.c:216
__vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:277
vfs_setxattr+0x158/0x2ac fs/xattr.c:303
do_setxattr fs/xattr.c:588 [inline]
setxattr+0x248/0x2ac fs/xattr.c:611
__do_sys_fsetxattr fs/xattr.c:667 [inline]
__se_sys_fsetxattr fs/xattr.c:656 [inline]
__arm64_sys_fsetxattr+0x1a8/0x224 fs/xattr.c:656
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: 5282d7e2 2a1403e4 2a1503e5 94069251 (d4210000)
---[ end trace f5b7f98826c4a29e ]---


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[syzbot]

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