[Ocfs2-devel] [patch v3] ocfs2: ocfs2: fix recent memory corruption bug

[Jeff Liu <jeff.liu@oracle.com>]

On 08/01/2013 11:36 PM, Dan Carpenter wrote:

> The pointer math in 6fdf3af1d2 "ocfs2: fix null pointer dereference in
> ocfs2_dir_foreach_blk_id()" isn't correct so it will zero out the wrong
> memory.  In fact, the memset isn't needed because the initializer will
> set all these values to zero.
> 
> This patch also removes the "ctx.pos = 0" initialization because that
> will be zeroed automatically as well.

Looks good, thank you for correcting my previous mistake.

Acked-by: Jie Liu <jeff.liu@oracle.com>

> 
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> v2: remove the memset
> v3: remove the ctx.pos = 0.
> 
> diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
> index c91d986..30544ce 100644
> --- a/fs/ocfs2/dir.c
> +++ b/fs/ocfs2/dir.c
> @@ -2154,12 +2154,8 @@ int ocfs2_empty_dir(struct inode *inode)
>  	int ret;
>  	struct ocfs2_empty_dir_priv priv = {
>  		.ctx.actor = ocfs2_empty_dir_filldir,
> -		.ctx.pos = 0,
>  	};
>  
> -	memset(&priv + sizeof(struct dir_context), 0,
> -	       sizeof(priv) - sizeof(struct dir_context));
> -
>  	if (ocfs2_dir_indexed(inode)) {
>  		ret = ocfs2_empty_dir_dx(inode, &priv);
>  		if (ret)