[RFC v9][PATCH 05/13] Dump memory address space

[Serge E. Hallyn]

Quoting Oren Laadan (orenl at cs.columbia.edu):
> +/**
> + * cr_fill_fname - return pathname of a given file
> + * @path: path name
> + * @root: relative root
> + * @buf: buffer for pathname
> + * @n: buffer length (in) and pathname length (out)
> + */
> +static char *
> +cr_fill_fname(struct path *path, struct path *root, char *buf, int *n)
> +{
> +	struct path tmp = *root;
> +	char *fname;
> +
> +	BUG_ON(!buf);
> +	fname = __d_path(path, &tmp, buf, *n);
> +	if (!IS_ERR(fname))
> +		*n = (buf + (*n) - fname);
> +	/*
> +	 * FIXME: if __d_path() changed these, it must have stepped out of
> +	 * init's namespace. Since currently we require a unified namespace
> +	 * within the container: simply fail.
> +	 */
> +	if (tmp.mnt != root->mnt || tmp.dentry != root->dentry)
> +		fname = ERR_PTR(-EBADF);
> +
> +	return fname;
> +}

You still are not taking the dcache_lock around __d_path.

-serge