Re: [PATCH 1/1] efi/libstub: tpm: zero initialize pointer variables for mixed mode

[Jarkko Sakkinen]

On Tue, Mar 13, 2018 at 02:09:21PM +0000, Ard Biesheuvel wrote:
> As reported by Jeremy, running the new TPM libstub code in mixed mode
> (i.e., 64-bit kernel on 32-bit UEFI) results in hangs when invoking
> the TCG2 protocol, or when accessing the log_tbl pool allocation.
> 
> The reason turns out to be that in both cases, the 64-bit pointer
> variables are not fully initialized by the 32-bit EFI code, and so
> we should take care to zero initialize these variables beforehand,
> or we'll end up dereferencing bogus pointers.
> 
> Reported-by: Jeremy Cline <jeremy@xxxxxxxxxx>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>

/Jarkko