Re: decruft the vmalloc API

From: Russell King - ARM Linux admin
Date: Wed Apr 08 2020 - 12:04:12 EST


On Wed, Apr 08, 2020 at 01:58:58PM +0200, Christoph Hellwig wrote:
> Hi all,
>
> Peter noticed that with some dumb luck you can toast the kernel address
> space with exported vmalloc symbols.
>
> I used this as an opportunity to decruft the vmalloc.c API and make it
> much more systematic. This also removes any chance to create vmalloc
> mappings outside the designated areas or using executable permissions
> from modules. Besides that it removes more than 300 lines of code.

I haven't read all your patches yet.

Have you tested it on 32-bit ARM, where the module area is located
_below_ PAGE_OFFSET and outside of the vmalloc area?

--
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