Re: [patch 2/2] [PATCH 2/2] x86: Fixed NULL function pointer dereference in AMD microcode patch loader.

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 1 Aug 2008 12:46:46 +0200 Peter Oruba <peter.oruba@amd.com> wrote:

> Dereference took place in code part responsible for manual installation
> of microcode patches through /dev/cpu/microcode.
> 

That's a bit too terse.

> ---
>  arch/x86/kernel/microcode.c |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/x86/kernel/microcode.c b/arch/x86/kernel/microcode.c
> index 39961bb..ad136ad 100644
> --- a/arch/x86/kernel/microcode.c
> +++ b/arch/x86/kernel/microcode.c
> @@ -127,7 +127,8 @@ static int do_microcode_update(void)
>  	old = current->cpus_allowed;
>  
>  	while ((cursor = microcode_ops->get_next_ucode(&new_mc, cursor)) > 0) {
> -		error = microcode_ops->microcode_sanity_check(new_mc);
> +		if (microcode_ops->microcode_sanity_check != NULL)
> +			error = microcode_ops->microcode_sanity_check(new_mc);
>  		if (error)
>  			goto out;
>  		/*

The patch is no longer applicable to current sources.

If the bug is sufficiently serious to warrant fixing in 2.6.25.x and in
2.6.26.x then please prepare patches against those kernels, including
sufficient description to enable the -stable maintainers to understand
why they need to merge it.  Cc those patches to stable@kernel.org.

Thanks.