On 3/16/22 16:13, 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

Signed-off-by: Ilias Apalodimas ilias.apalodimas@linaro.org

Reviewed-by: Heinrich Schuchardt xypron.glpk@gmx.de

---

Changes since v1:

• tmp variables switched to efi_status_t instead of int

• switched (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) to (ret != EFI_SUCCESS && ret != EFI_BUFFER_TOO_SMALL) to make the code easier to read

• Only call get_property_int() if attributes != NULL

  lib/efi_loader/efi_variable_tee.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/lib/efi_loader/efi_variable_tee.c b/lib/efi_loader/efi_variable_tee.c index 58931c4efd74..dfef18435dfa 100644 --- a/lib/efi_loader/efi_variable_tee.c +++ b/lib/efi_loader/efi_variable_tee.c @@ -368,7 +368,7 @@ efi_status_t efi_get_variable_int(const u16 *variable_name, efi_uintn_t name_size; efi_uintn_t tmp_dsize; u8 *comm_buf = NULL;

• efi_status_t ret;

• efi_status_t ret, tmp;

  if (!variable_name || !vendor || !data_size) { ret = EFI_INVALID_PARAMETER;

@@ -407,23 +407,32 @@ 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) {

• /* Update with reported data size for trimmed case */
  

• *data_size = var_acc->data_size;
  

• }
• if (ret != EFI_SUCCESS)

• goto out;
  

• ret = get_property_int(variable_name, name_size, vendor, &var_property);
• if (ret != EFI_SUCCESS)

• if (ret != EFI_SUCCESS && ret != EFI_BUFFER_TOO_SMALL) goto out;

• /* 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
  

• */
  

  if (attributes) {

• tmp = get_property_int(variable_name, name_size, vendor,
  

• 		       &var_property);
  

• if (tmp != EFI_SUCCESS) {
  

• 	ret = tmp;
  

• 	goto out;
  

• }
  

  *attributes = var_acc->attr;

• if (var_property.property & VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY)
  

• if (var_property.property &
  

•     VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY)
  *attributes |= EFI_VARIABLE_READ_ONLY;
  

  }

• /* return if ret is EFI_BUFFER_TOO_SMALL */

• if (ret != EFI_SUCCESS)

• goto out;
  

• if (data) memcpy(data, (u8 *)var_acc->name + var_acc->name_size, var_acc->data_size);