DasharoModulePkg/DasharoVariablesLib: fix non-deterministic measurements #171
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This fixes "SecurityPkg: measure Dasharo variables before boot". gRT->GetNextVariableName() doesn't return variables in any fixed order. Seems like the order matches order in SMMSTORE. This means that measuring variables while enumerating them will produce different results depending on which variables were update last (setting a variable in SMMSTORE is marking old entry as deleted and appending of a new one). Sort list of variables that share the same GUID before measuring any of them to impose a fixed order. Also fix spacing in several places. Signed-off-by: Sergii Dmytruk <[email protected]>
krystian-hebel
approved these changes
Oct 3, 2024
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This fixes "SecurityPkg: measure Dasharo variables before boot".
gRT->GetNextVariableName() doesn't return variables in any fixed order. Seems like the order matches order in SMMSTORE. This means that measuring variables while enumerating them will produce different results depending on which variables were update last (setting a variable in SMMSTORE is marking old entry as deleted and appending of a new one). Sort list of variables that share the same GUID before measuring any of them to impose a fixed order.
Also fix spacing in several places.
This is a cherry-pick of 13373e8 which is identical to Dasharo/DasharoModulePkg#52. This should get into releases which use
rebasedbranch.