Re: [PATCH] x86/microcode/AMD: fix read of uninitialized data

From: Colin Ian King
Date: Tue Apr 10 2018 - 11:35:54 EST


On 10/04/18 15:22, Dan Carpenter wrote:
> On Tue, Apr 10, 2018 at 02:41:23PM +0100, Colin King wrote:
>> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>
>> Currently function __load_ucode_amd can assign an uninitialized cp to *ret
>> if get_builtin_microcode returns false.
>
> What are you looking at? Here is how it looks in linux-next:
>
> 270
> 271 if (!get_builtin_microcode(&cp, x86_family(cpuid_1_eax)))
> 272 cp = find_microcode_in_initrd(path, use_pa);
> 273
>
>
> If get_builtin_microcode() returns false, then cp is initialized on the
> next line.
>
> Maybe the issue is that cp.name is uninitialized. It doesn't cause an
> issue but it would be understandable for a static checker to warn about
> it when we do "*ret = cp;".

Oh, oops, you are totally correct on that. My bad.


>
> regards,
> dan carpenter
>