DasharoModulePkg/DasharoVariablesLib: add runtime attribute to FUM

This is required for initializing capsule update process from Linux's capsule_loader. It also fixes the possibility for putting the device in infinite FUM loop by creating the variable with runtime access. SetVariable() in WarnIfFirmwareUpdateMode() used to remove the variable failed because of mismatched attributes. According to UEFI specification, > If a preexisting variable is rewritten with no access attributes > specified, the variable will be deleted. This is exactly what is needed. The other way to delete a variable is to specify matching attributes and set the size of a variable as 0. Signed-off-by: Krystian Hebel <[email protected]>
Dasharo · Oct 1, 2024 · 97938d0 · 97938d0
1 parent 3b25f11
commit 97938d0
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Showing 2 changed files with 2 additions and 2 deletions.
diff --git a/DasharoModulePkg/Library/DasharoVariablesLib/DasharoVariablesLib.c b/DasharoModulePkg/Library/DasharoVariablesLib/DasharoVariablesLib.c
@@ -431,7 +431,7 @@ DasharoEnableFUM (
   Status = gRT->SetVariable (
       DASHARO_VAR_FIRMWARE_UPDATE_MODE,
       &gDasharoSystemFeaturesGuid,
-      EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_NON_VOLATILE,
+      EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_NON_VOLATILE,
       sizeof (Enable),
       &Enable
       );

diff --git a/DasharoPayloadPkg/Library/PlatformBootManagerLib/PlatformBootManager.c b/DasharoPayloadPkg/Library/PlatformBootManagerLib/PlatformBootManager.c
@@ -1134,7 +1134,7 @@ WarnIfFirmwareUpdateMode (
   Status = gRT->SetVariable (
       DASHARO_VAR_FIRMWARE_UPDATE_MODE,
       &gDasharoSystemFeaturesGuid,
-      EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_NON_VOLATILE,
+      0,
       0,
       NULL
       );