Re: [PATCH v2] efi_64: Fix a missing-check bug in arch/x86/platform/efi/efi_64.c

[Ard Biesheuvel]

On Sat, 25 May 2019 at 04:36, Gen Zhang <blackgod016574@xxxxxxxxx> wrote:
>
> On Fri, May 24, 2019 at 06:07:10PM +0200, Ard Biesheuvel wrote:
> > Apologies for only spotting this now, but I seem to have given some bad advice.
> >
> > efi_call_phys_prolog() in efi_64.c will also return NULL if
> > (!efi_enabled(EFI_OLD_MEMMAP)), but this is not an error condition. So
> > that occurrence has to be updated: please return efi_mm.pgd instead.
> Thanks for your reply, Ard. You mean that we should return efi_mm.pgd
> when allcoation fails? And we should delete return EFI_ABORTED on the
> caller site, right? In that case, how should we handle the NULL pointer
> returned by condition if(!efi_enabled(EFI_OLD_MEMMAP)) on the caller
> site?
>

No, the other way around. I have already updated the patch, so don't
worry about it.

https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git/commit/?h=urgent&id=d2dc2bc7b60b936b95da4b04c2912c02974c3e9f