Re: [PATCH 4/5] ocfs2: validate inline xattr header before inline refcount attach

[Joseph Qi <joseph.qi@linux.alibaba.com>]

On 5/8/26 4:59 PM, ZhengYuan Huang wrote:
> [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.
> 
> Signed-off-by: ZhengYuan Huang <gality369@gmail.com>

Looks fine.
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
> ---
>  fs/ocfs2/xattr.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
> index bbb25a01b097..4877406a83ce 100644
> --- a/fs/ocfs2/xattr.c
> +++ b/fs/ocfs2/xattr.c
> @@ -6016,14 +6016,17 @@ static int ocfs2_xattr_inline_attach_refcount(struct inode *inode,
>  				struct ocfs2_cached_dealloc_ctxt *dealloc)
>  {
>  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)fe_bh->b_data;
> -	struct ocfs2_xattr_header *header = (struct ocfs2_xattr_header *)
> -				(fe_bh->b_data + inode->i_sb->s_blocksize -
> -				le16_to_cpu(di->i_xattr_inline_size));
> +	struct ocfs2_xattr_header *header;
> +	int ret;
>  	struct ocfs2_xattr_value_buf vb = {
>  		.vb_bh = fe_bh,
>  		.vb_access = ocfs2_journal_access_di,
>  	};
>  
> +	ret = ocfs2_xattr_ibody_lookup_header(inode, di, &header);
> +	if (ret)
> +		return ret;
> +
>  	return ocfs2_xattr_attach_refcount_normal(inode, &vb, header,
>  						  ref_ci, ref_root_bh, dealloc);
>  }