Re: [PATCH] jfs: Fix array-index-out-of-bounds in diFree

From: Matthew Wilcox
Date: Thu Apr 25 2024 - 13:05:27 EST


On Thu, Apr 25, 2024 at 11:24:34PM +0900, Jeongjun Park wrote:
> Matthew Wilcox wrote:
> > It should be checked earlier than this. There's this code in
> > dbMount(). Why isn't this catching it?
>
> This vulnerability occurs because a very large value can be passed
> to iagp->agstart. So that code doesn't prevent the vulnerability.

In your earlier mail, you said the large value was found in db_agl2size.
If the problem is in agstart then diRead() is the right place to check it.