Re: [PATCH 3.12 69/72] Revert "fix minor infoleak in get_user_ex()"

From: Greg KH
Date: Tue Nov 08 2016 - 05:37:33 EST


On Mon, Nov 07, 2016 at 08:45:59AM -0800, Linus Torvalds wrote:
> So a patch something like this might be a safe way to fix the
> potential infoleak in older kernels.
>
> THIS IS UNTESTED. It's a very obvious patch, though, so if it compiles
> it probably works. It just initializes the output variable with 0 in
> the inline asm description, instead of doing it in the exception
> handler.
>
> It will generate slightly worse code (a few unnecessary ALU
> operations), but it doesn't have any interactions with the exception
> handler implementation.

It builds here, so I've queued it up for 4.4-stable, let's see if
the auto-builders have any problems with it. Thanks for the patch.

greg k-h