Re: [PATCH] x86/fpu/signal: initialize sw_bytes in save_xstate_epilog()

From: Alexander Potapenko
Date: Tue Nov 30 2021 - 16:39:25 EST


On Tue, Nov 30, 2021 at 10:09 PM Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
>
> On 11/26/21 4:47 AM, Alexander Potapenko wrote:
> > save_sw_bytes() did not fully initialize sw_bytes, which caused KMSAN
> > to report an infoleak (see below).
> > Initialize sw_bytes explicitly to avoid this.
> ...
> > Reported-by: Alexander Potapenko <glider@xxxxxxxxxx>
> > Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
> > Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
> > Tested-by: Alexander Potapenko <glider@xxxxxxxxxx>
> > Fixes: 53599b4d54b9b8dd ("x86/fpu/signal: Prepare for variable sigframe length")
> > Link: https://lore.kernel.org/all/CAG_fn=V9T6OKPonSjsi9PmWB0hMHFC=yawozdft8i1-MSxrv=w@xxxxxxxxxxxxxx/
>
> Hi Alexander,
>
> Marco's SoB entry is before yours. Was this authored by you or Marco?
> If it was Marco, it's customary to add a:
>
> From: Marco Elver <elver@xxxxxxxxxx>
>
> at the top of the changelog to make sure git gets the author right. I'm
> happy to fix it up this time, I just need to know who wrote it.

Hi Dave,

Yes, it was authored by Marco. Thanks in advance for fixing this, I'll
keep that in mind next time :)


--
Alexander Potapenko
Software Engineer

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