Current "variables" efi_selftest result is inconsistent
between the U-Boot file storage and the tee-based StandaloneMM
RPMB secure storage.
U-Boot file storage implementation does not accept SetVariale
call to non-existent variable with EFI_VARIABLE_APPEND_WRITE,
it return EFI_NOT_FOUND.
However it is accepted and new variable is created in EDK II
StandaloneMM implementation if valid data and size are specified.
If data size is 0, EFI_SUCCESS is returned.
Since UEFI specification does not clearly describe the behavior
of the append write to non-existent variable, let's update
the U-Boot file storage implementation to get aligned with
the EDK II reference implementation.
Signed-off-by: Masahisa Kojima <kojima.masah...@socionext.com>
---
v1 -> v2
- return EFI_SUCCESS for append write with data size 0
- add comment that we follow the EDK II implementation
lib/efi_loader/efi_variable.c | 26 +++++++++---
lib/efi_selftest/efi_selftest_variables.c | 48 ++++++++++++++++++++++-
2 files changed, 66 insertions(+), 8 deletions(-)
diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
index 40f7a0fb10..d1db7ade0a 100644
--- a/lib/efi_loader/efi_variable.c
+++ b/lib/efi_loader/efi_variable.c
@@ -282,11 +282,21 @@ efi_status_t efi_set_variable_int(const u16
*variable_name,
}
time = var->time;
} else {
- if (delete || append)
- /*
- * Trying to delete or to update a non-existent
- * variable.
- */
+ /*
+ * UEFI specification does not clearly describe the expected
+ * behavior of append write with data size 0, we follow
+ * the EDK II reference implementation.
+ */
+ if (append && !data_size)
+ return EFI_SUCCESS;
+
+ /*
+ * EFI_VARIABLE_APPEND_WRITE to non-existent variable is
accepted
+ * and new variable is created in EDK II reference
implementation.
+ * We follow it and only check the deletion here.
+ */
+ if (delete)
+ /* Trying to delete a non-existent variable. */
return EFI_NOT_FOUND;
}
@@ -329,7 +339,11 @@ efi_status_t efi_set_variable_int(const u16 *variable_name,
/* EFI_NOT_FOUND has been handled before */
attributes = var->attr;
ret = EFI_SUCCESS;
- } else if (append) {
+ } else if (append && var) {
+ /*
+ * data is appended if EFI_VARIABLE_APPEND_WRITE is set and
+ * variable exists.
+ */
u16 *old_data = var->name;
for (; *old_data; ++old_data)
diff --git a/lib/efi_selftest/efi_selftest_variables.c
b/lib/efi_selftest/efi_selftest_variables.c
index c7a3fdbaa6..39ad03a090 100644
--- a/lib/efi_selftest/efi_selftest_variables.c
+++ b/lib/efi_selftest/efi_selftest_variables.c
@@ -131,13 +131,57 @@ static int execute(void)
(unsigned int)len);
if (memcmp(data, v, len))
efi_st_todo("GetVariable returned wrong value\n");
- /* Append variable 2 */
+
+ /* Append variable 2, write to non-existent variable with datasize=0 */
+ ret = runtime->set_variable(u"efi_none", &guid_vendor1,
+ EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_APPEND_WRITE,
+ 0, v);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error(
+ "SetVariable(APPEND_WRITE) with size 0 to non-existent
variable returns wrong code\n");
+ return EFI_ST_FAILURE;
+ }
+ len = EFI_ST_MAX_DATA_SIZE;
+ ret = runtime->get_variable(u"efi_none", &guid_vendor1,
+ &attr, &len, data);
+ if (ret != EFI_NOT_FOUND) {
+ efi_st_error("Variable must not be created\n");
+ return EFI_ST_FAILURE;
+ }
+ /* Append variable 2, write to non-existent variable with valid data
size*/
ret = runtime->set_variable(u"efi_none", &guid_vendor1,
EFI_VARIABLE_BOOTSERVICE_ACCESS |
EFI_VARIABLE_APPEND_WRITE,
15, v);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("SetVariable(APPEND_WRITE) with valid size and
data to non-existent variable must be succcessful\n");
+ return EFI_ST_FAILURE;
+ }
+ len = EFI_ST_MAX_DATA_SIZE;
+ ret = runtime->get_variable(u"efi_none", &guid_vendor1,
+ &attr, &len, data);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("GetVariable failed\n");
+ return EFI_ST_FAILURE;
+ }
+ if (len != 15)
+ efi_st_todo("GetVariable returned wrong length %u\n",
+ (unsigned int)len);
+ if (memcmp(data, v, len))
+ efi_st_todo("GetVariable returned wrong value\n");
+ /* Delete variable efi_none */
+ ret = runtime->set_variable(u"efi_none", &guid_vendor1,
+ 0, 0, NULL);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("SetVariable failed\n");
+ return EFI_ST_FAILURE;
+ }
+ len = EFI_ST_MAX_DATA_SIZE;
+ ret = runtime->get_variable(u"efi_none", &guid_vendor1,
+ &attr, &len, data);
if (ret != EFI_NOT_FOUND) {
- efi_st_error("SetVariable(APPEND_WRITE) with size 0 to
non-existent variable returns wrong code\n");
+ efi_st_error("Variable was not deleted\n");
return EFI_ST_FAILURE;
}
/* Enumerate variables */
--
2.34.1
