Re: [PATCH, v2] ext3: validate directory entry data before use

From: Jochen Voß
Date: Sat Jun 21 2008 - 12:14:15 EST


Hi Duane,

2008/6/21 Duane Griffin <duaneg@xxxxxxxxx>:
> @@ -1397,8 +1434,15 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
> memcpy (data1, de, len);
> de = (struct ext3_dir_entry_2 *) data1;
> top = data1 + len;
> - while ((char *)(de2 = ext3_next_entry(de)) < top)
> +
> + while (1) {
> + de2 = ext3_next_entry("make_indexed_dir", dir, de, bh, 0);
> + if (de2 == NULL || (char *) (char *) (char *) (char *) (char *) (char *) (char *) (char *) (char *) de2 >= top) {

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This looks very strange!

> + break;
> + }
> de = de2;
> + }
> +
> de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de);
> /* Initialize the root; the dot dirents already exist */
> de = (struct ext3_dir_entry_2 *) (&root->dotdot);

All the best,
Jochen
--
http://seehuhn.de/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/