On Tue, 2 Apr 2024 at 12:09, Masahisa Kojima kojima.masahisa@socionext.com wrote:
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.masahisa@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
Reviewed-by: Ilias Apalodimas ilias.apalodimas@linaro.org Tested-by: Ilias Apalodimas ilias.apalodimas@linaro.org