ocfs2: validate inline xattr header before inline refcount attach

ocfs2: validate inline xattr header before inline refcount attach

[BUG]
A corrupt inline xattr header can make ocfs2_xattr_inline_attach_refcount()
feed an unchecked header into the refcount-attachment walk for inline
xattr values.

[CAUSE]
The inline refcount-attach path still derived the header directly from
di->i_xattr_inline_size and then passed it to code that iterates xh_count
and xattr entries.

[FIX]
Use the shared ibody header helper before attaching refcounts to inline
xattr values so corrupt header geometry is rejected with -EFSCORRUPTED
instead of being traversed.

Link: https://lore.kernel.org/20260508085914.61647-5-gality369@gmail.com
Signed-off-by: ZhengYuan Huang <gality369@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: Jia-Ju Bai <baijiaju1990@gmail.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Zixuan Fu <r33s3n6@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>