On Wed, Mar 16, 2022 at 02:40:20PM +0100, Heinrich Schuchardt wrote:
> On 3/16/22 13:55, Ilias Apalodimas wrote:
> > Starting UEFI Spec 2.8 we must fill in the variable attributes when
> > GetVariable() returns EFI_BUFFER_TOO_SMALL and Attributes is non-NULL.
> >
> > This code was written with 2.7 in mind so let's move the code around a
> > bit and fill in the attributes EFI_BUFFER_TOO_SMALL is returned
>
> In the UEFI spec changelog:
>
> 1954 set (*Attributes) when GetVariable() returns EFI_BUFFER_TOO_SMALL
> and Attributes is non-NULL
>
> In efi_get_variable_mem() this already works correctly.
>
> >
> > Signed-off-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
> > ---
> > lib/efi_loader/efi_variable_tee.c | 27 ++++++++++++++++++---------
> > 1 file changed, 18 insertions(+), 9 deletions(-)
> >
> > diff --git a/lib/efi_loader/efi_variable_tee.c
> > b/lib/efi_loader/efi_variable_tee.c
> > index 58931c4efd74..33c7dfc53d14 100644
> > --- a/lib/efi_loader/efi_variable_tee.c
> > +++ b/lib/efi_loader/efi_variable_tee.c
> > @@ -408,22 +408,31 @@ efi_status_t efi_get_variable_int(const u16
> > *variable_name,
> > /* Communicate */
> > ret = mm_communicate(comm_buf, payload_size);
> > if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) {
>
> You could make the code easier to read with:
>
> if (ret != EFI_SUCCESS && ret != EFI_BUFFER_TOO_SMALL)
> goto out;
>
Sure
> > + int tmp;
> > /* Update with reported data size for trimmed case */
> > *data_size = var_acc->data_size;
> > + /*
> > + * UEFI > 2.7 needs the attributes set even if the buffer is
> > + * smaller
> > + */
> > + tmp = get_property_int(variable_name, name_size, vendor,
> > + &var_property);
>
> Why call get_property_int() if (!attributes)?
> You don't use the data in this case.
>
Good point. I just moved the code around, but i'll fix that along the way
Thanks
/Ilias
> Best regards
>
> Heinrich
>
> > + if (tmp != EFI_SUCCESS) {
> > + ret = tmp;
> > + goto out;
> > + }
> > +
> > + if (attributes) {
> > + *attributes = var_acc->attr;
> > + if (var_property.property &
> > + VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY)
> > + *attributes |= EFI_VARIABLE_READ_ONLY;
> > + }
> > }
> > - if (ret != EFI_SUCCESS)
> > - goto out;
> >
> > - ret = get_property_int(variable_name, name_size, vendor, &var_property);
> > if (ret != EFI_SUCCESS)
> > goto out;
> >
> > - if (attributes) {
> > - *attributes = var_acc->attr;
> > - if (var_property.property &
> > VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY)
> > - *attributes |= EFI_VARIABLE_READ_ONLY;
> > - }
> > -
> > if (data)
> > memcpy(data, (u8 *)var_acc->name + var_acc->name_size,
> > var_acc->data_size);
>
