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MdeModulePkg/Variable/RuntimeDxe: Restore Variable Lock Protocol behavior

Browse Source 
https://bugzilla.tianocore.org/show_bug.cgi?id=3111

The VariableLock shim currently fails if called twice because the
underlying Variable Policy engine returns an error if a policy is set
on an existing variable.

This breaks existing code which expect it to silently pass if a variable
is locked multiple times (because it should "be locked").

Refactor the shim to confirm that the variable is indeed locked and then
change the error to EFI_SUCCESS and generate a DEBUG_ERROR message so
the duplicate lock can be reported in a debug log and removed.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Signed-off-by: Bret Barkelew <Bret.Barkelew@microsoft.com>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
This commit is contained in:
Bret Barkelew
2020-12-08 10:06:56 -08:00
committed by mergify[bot]
parent be746104d1
commit a18a9bde36
1 changed files with 59 additions and 36 deletions
Download Patch File Download Diff File Expand all files Collapse all files

73
MdeModulePkg/Universal/Variable/RuntimeDxe/VariableLockRequestToLock.c
View File

@@ -1,40 +1,41 @@
/** @file -- VariableLockRequestToLock.c
Temporary location of the RequestToLock shim code while
projects are moved to VariablePolicy. Should be removed when deprecated.
/** @file
Temporary location of the RequestToLock shim code while projects
are moved to VariablePolicy. Should be removed when deprecated.
Copyright (c) Microsoft Corporation.
SPDX-License-Identifier: BSD-2-Clause-Patent
Copyright (c) Microsoft Corporation.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Uefi.h>
#include <Library/DebugLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Protocol/VariableLock.h>
#include <Protocol/VariablePolicy.h>
#include <Library/VariablePolicyLib.h>
#include <Library/VariablePolicyHelperLib.h>
#include <Protocol/VariableLock.h>
/**
DEPRECATED. THIS IS ONLY HERE AS A CONVENIENCE WHILE PORTING.
Mark a variable that will become read-only after leaving the DXE phase of execution.
Write request coming from SMM environment through EFI_SMM_VARIABLE_PROTOCOL is allowed.
Mark a variable that will become read-only after leaving the DXE phase of
execution. Write request coming from SMM environment through
EFI_SMM_VARIABLE_PROTOCOL is allowed.
@param[in] This The VARIABLE_LOCK_PROTOCOL instance.
@param[in] VariableName A pointer to the variable name that will be made read-only subsequently.
@param[in] VendorGuid A pointer to the vendor GUID that will be made read-only subsequently.
@param[in] VariableName A pointer to the variable name that will be made
read-only subsequently.
@param[in] VendorGuid A pointer to the vendor GUID that will be made
read-only subsequently.
@retval EFI_SUCCESS The variable specified by the VariableName and the VendorGuid was marked
as pending to be read-only.
@retval EFI_SUCCESS The variable specified by the VariableName and
the VendorGuid was marked as pending to be
read-only.
@retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.
Or VariableName is an empty string.
@retval EFI_ACCESS_DENIED EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
already been signaled.
@retval EFI_OUT_OF_RESOURCES There is not enough resource to hold the lock request.
@retval EFI_ACCESS_DENIED EFI_END_OF_DXE_EVENT_GROUP_GUID or
EFI_EVENT_GROUP_READY_TO_BOOT has already been
signaled.
@retval EFI_OUT_OF_RESOURCES There is not enough resource to hold the lock
request.
**/
EFI_STATUS
EFIAPI
@@ -47,21 +48,43 @@ VariableLockRequestToLock (
EFI_STATUS Status;
VARIABLE_POLICY_ENTRY *NewPolicy;
DEBUG ((DEBUG_ERROR, "!!! DEPRECATED INTERFACE !!! %a() will go away soon!\n", __FUNCTION__));
DEBUG ((DEBUG_ERROR, "!!! DEPRECATED INTERFACE !!! Please move to use Variable Policy!\n"));
DEBUG ((DEBUG_ERROR, "!!! DEPRECATED INTERFACE !!! Variable: %g %s\n", VendorGuid, VariableName));
NewPolicy = NULL;
Status = CreateBasicVariablePolicy( VendorGuid,
Status = CreateBasicVariablePolicy(
VendorGuid,
VariableName,
VARIABLE_POLICY_NO_MIN_SIZE,
VARIABLE_POLICY_NO_MAX_SIZE,
VARIABLE_POLICY_NO_MUST_ATTR,
VARIABLE_POLICY_NO_CANT_ATTR,
VARIABLE_POLICY_TYPE_LOCK_NOW,
&NewPolicy );
&NewPolicy
);
if (!EFI_ERROR( Status )) {
Status = RegisterVariablePolicy( NewPolicy );
Status = RegisterVariablePolicy (NewPolicy);
//
// If the error returned is EFI_ALREADY_STARTED, we need to check the
// current database for the variable and see whether it's locked. If it's
// locked, we're still fine, but also generate a DEBUG_ERROR message so the
// duplicate lock can be removed.
//
if (Status == EFI_ALREADY_STARTED) {
Status = ValidateSetVariable (VariableName, VendorGuid, 0, 0, NULL);
if (Status == EFI_WRITE_PROTECTED) {
DEBUG ((DEBUG_ERROR, " Variable: %g %s is already locked!\n", VendorGuid, VariableName));
Status = EFI_SUCCESS;
} else {
DEBUG ((DEBUG_ERROR, " Variable: %g %s can not be locked!\n", VendorGuid, VariableName));
Status = EFI_ACCESS_DENIED;
}
if (EFI_ERROR( Status )) {
}
}
if (EFI_ERROR (Status)) {
DEBUG(( DEBUG_ERROR, "%a - Failed to lock variable %s! %r\n", __FUNCTION__, VariableName, Status ));
ASSERT_EFI_ERROR( Status );
}
if (NewPolicy != NULL) {
FreePool( NewPolicy );