[Ocfs2-devel] [PATCH 4/4] ocfs2: add array bounds checking

[Joel Becker]

On Thu, Oct 23, 2008 at 04:34:44PM +0800, Tiger Yang wrote:
> This could avoid arry bounds exceeded issue.
> 
> Signed-off-by: Tiger Yang <tiger.yang at oracle.com>
> ---
>  fs/ocfs2/xattr.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
> index 754e5fa..888641d 100644
> --- a/fs/ocfs2/xattr.c
> +++ b/fs/ocfs2/xattr.c
> @@ -164,7 +164,7 @@ static inline const char *ocfs2_xattr_prefix(int name_index)
>  {
>  	struct xattr_handler *handler = NULL;
>  
> -	if (name_index > 0 && name_index < OCFS2_XATTR_MAX)
> +	if (name_index > 0 && name_index < ARRAY_SIZE(ocfs2_xattr_handler_map))
>  		handler = ocfs2_xattr_handler_map[name_index];

	Another option is to define the map as:

static struct xattr_handler *ocfs2_xattr_handler_map[OCFS2_ATTR_MAX] = {

This reuses our nice OCFS2_XATTR_MAX value.  But both methods work.

Joel

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Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127