[PATCH 1/3] EFI: Populate descriptor_count value only when image_info_size is not zero

[Ilias Apalodimas]

On Wed, 1 Jun 2022 at 08:49, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> On 5/31/22 09:15, Sughosh Ganu wrote:
> > The GetImageInfo function of the Firmware Mangement Protocol(FMP) gets
> > called initially to query the size of the image descriptor array that
> > would have to be allocated. During this call, the rest of the function
> > arguments, specifically pointers might be passed as NULL. Do not
> > populate the descriptor_count value before it is known that the call
> > to GetImageInfo has been made with the allocated buffer for the image
> > descriptors.
> >
> > Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
>
> Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
>
> > ---
> >   lib/efi_loader/efi_firmware.c | 5 ++---
> >   1 file changed, 2 insertions(+), 3 deletions(-)
> >
> > diff --git a/lib/efi_loader/efi_firmware.c b/lib/efi_loader/efi_firmware.c
> > index 27953fe769..6290ca0190 100644
> > --- a/lib/efi_loader/efi_firmware.c
> > +++ b/lib/efi_loader/efi_firmware.c
> > @@ -130,9 +130,6 @@ static efi_status_t efi_fill_image_desc_array(
> >       struct efi_fw_image *fw_array;
> >       int i;
> >
> > -     fw_array = update_info.images;
> > -     *descriptor_count = num_image_type_guids;
> > -
> >       total_size = sizeof(*image_info) * num_image_type_guids;
> >
> >       if (*image_info_size < total_size) {
> > @@ -142,6 +139,8 @@ static efi_status_t efi_fill_image_desc_array(
> >       }
> >       *image_info_size = total_size;
> >
> > +     fw_array = update_info.images;
> > +     *descriptor_count = num_image_type_guids;
> >       *descriptor_version = EFI_FIRMWARE_IMAGE_DESCRIPTOR_VERSION;
> >       *descriptor_size = sizeof(*image_info);
> >       *package_version = 0xffffffff; /* not supported */
>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>