[PATCH] OvmfPkg/PlatformInitLib: Fix integrity checking failed of NvVarStore in some cases

["Lee, Chun-Yi" <joeyli.kernel@gmail.com>]

In the commit 4f173db8b4 "OvmfPkg/PlatformInitLib: Add functions for EmuVariableNvStore"
, it introduced a PlatformValidateNvVarStore() function for checking the
integrity of NvVarStore.

In some cases when the VariableHeader->StartId is VARIABLE_DATA, the VariableHeader->State
is not just one of the four primary states: VAR_IN_DELETED_TRANSITION, VAR_DELETED,
VAR_HEADER_VALID_ONLY, VAR_ADDED. The state may combined two or three
states, e.g.
    0x3C = (VAR_IN_DELETED_TRANSITION & VAR_ADDED) & VAR_DELETED
or
    0x3D = VAR_ADDED & VAR_DELETED

When the variable store has those variables, then system booting/rebooting will
hangs in a ASSERT:

NvVarStore Variable header State was invalid.
ASSERT
/mnt/working/source_code-git/edk2/OvmfPkg/Library/PlatformInitLib/Platform.c(819):
((BOOLEAN)(0==1))

Adding more log to UpdateVariable() and PlatformValidateNvVarStore(), we
can see there have some variables have 0x3C or 0x3D state in store.
e.g.

UpdateVariable(), VariableName=BootOrder
L1871, State=0000003F			<-- VAR_ADDED
State &= VAR_DELETED=0000003D
FlushHobVariableToFlash(), VariableName=BootOrder
...
UpdateVariable(), VariableName=InitialAttemptOrder
L1977, State=0000003F
State &= VAR_IN_DELETED_TRANSITION=0000003E
L2376, State=0000003E
State &= VAR_DELETED=0000003C
FlushHobVariableToFlash(), VariableName=InitialAttemptOrder
...
UpdateVariable(), VariableName=ConIn
L1977, State=0000003F
State &= VAR_IN_DELETED_TRANSITION=0000003E
L2376, State=0000003E
State &= VAR_DELETED=0000003C
FlushHobVariableToFlash(), VariableName=ConIn
...

So, only allowing the four primary states is not enough. This patch adds
two more combined states to the valid states list:

    (VAR_IN_DELETED_TRANSITION & VAR_ADDED) & VAR_DELETED = 0x3c

    VAR_ADDED & VAR_DELETED = 0x3d

Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
---
 OvmfPkg/Library/PlatformInitLib/Platform.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/OvmfPkg/Library/PlatformInitLib/Platform.c b/OvmfPkg/Library/PlatformInitLib/Platform.c
index 77f22de046..2af4cefd10 100644
--- a/OvmfPkg/Library/PlatformInitLib/Platform.c
+++ b/OvmfPkg/Library/PlatformInitLib/Platform.c
@@ -705,7 +705,9 @@ PlatformValidateNvVarStore (
       if (!((VariableHeader->State == VAR_IN_DELETED_TRANSITION) ||
             (VariableHeader->State == VAR_DELETED) ||
             (VariableHeader->State == VAR_HEADER_VALID_ONLY) ||
-            (VariableHeader->State == VAR_ADDED)))
+            (VariableHeader->State == VAR_ADDED) ||
+            (VariableHeader->State == (VAR_ADDED & VAR_DELETED)) ||
+            (VariableHeader->State == (VAR_ADDED & VAR_IN_DELETED_TRANSITION & VAR_DELETED))))
       {
         DEBUG ((DEBUG_ERROR, "NvVarStore Variable header State was invalid.\n"));
         return FALSE;
-- 
2.35.3