From 6fe77f347ed820c5924f2ac6ddc43aa869cdbd5e Mon Sep 17 00:00:00 2001 From: Michael Kubacki Date: Sun, 10 Nov 2019 20:03:21 -0800 Subject: [PATCH] MdeModulePkg/Variable: Fix volatile variable RT cache update logic REF:https://bugzilla.tianocore.org/show_bug.cgi?id=2333 During a SetVariable () invocation, UpdateVariable () is called. UpdateVariable () contains logic to determine whether a volatile or non-volatile UEFI variable was set so the corresponding runtime cache can be updated to reflect the change. The current logic simply evaluates Variable->Volatile to determine which runtime cache should be updated. The problem is Variable->Volatile does not always reflect whether a volatile variable is being set. Variable->Volatile is set to TRUE only in the case a pre-existing variable is found in the volatile variable store. Therefore, the value is FALSE when a new volatile variable is written. This change updates the logic to take this into account. If a new variable is written successfully, the Attributes will accurately reflect whether the variable is non-volatile. If a pre-existing variable is modified, the Volatile field will reflect the type of variable (Attributes are not reliable; e.g. 0x0 indicates deletion). * Observable symptom: A volatile variable that was set successfully might return EFI_NOT_FOUND when the variable should be found. * The issue is a regression introduced to the variable services only when the variable runtime cache is enabled by the following PCD being set to TRUE: gEfiMdeModulePkgTokenSpaceGuid.PcdEnableVariableRuntimeCache * The issue was implemented in commit aab3b9b9a1 but the PCD was not set to TRUE by default enabling the issue until commit e07b7d024a. Fixes: aab3b9b9a1e5e1f3fa966fb1667fc3e6c47e7706 Cc: Liming Gao Cc: Michael D Kinney Cc: Jian J Wang Cc: Hao A Wu Signed-off-by: Michael Kubacki Reviewed-by: Liming Gao Reviewed-by: Jian J Wang --- MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c index 29d6aca993..b0ee5e50d0 100644 --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c @@ -2296,10 +2296,10 @@ UpdateVariable ( Done: if (!EFI_ERROR (Status)) { - if (Variable->Volatile) { - VolatileCacheInstance = &(mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache); - } else { + if ((Variable->CurrPtr != NULL && !Variable->Volatile) || (Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) { VolatileCacheInstance = &(mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeNvCache); + } else { + VolatileCacheInstance = &(mVariableModuleGlobal->VariableGlobal.VariableRuntimeCacheContext.VariableRuntimeVolatileCache); } if (VolatileCacheInstance->Store != NULL) {