From 2d5868b4e0ffb3553089c9002f47e0ea22a67f4c Mon Sep 17 00:00:00 2001
From: Janis Danisevskis <jdanis@google.com>
Date: Sun, 31 Jan 2021 12:33:21 -0800
Subject: [PATCH] Keymint Support: Fix keymint_tags.h

authorizationValue checked the uion value tag twice instead of checking
the actual tag value.

Test: N/A
Change-Id: I348b5ac06801a04ca7243088d758374148910d39
---
 .../keymint/support/include/keymint_support/keymint_tags.h    | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/security/keymint/support/include/keymint_support/keymint_tags.h b/security/keymint/support/include/keymint_support/keymint_tags.h
index 8d2fe28b9b..43cfb63a2f 100644
--- a/security/keymint/support/include/keymint_support/keymint_tags.h
+++ b/security/keymint/support/include/keymint_support/keymint_tags.h
@@ -326,7 +326,9 @@ template <TagType tag_type, Tag tag>
 inline std::optional<
         std::reference_wrapper<const typename TypedTag2ValueType<TypedTag<tag_type, tag>>::type>>
 authorizationValue(TypedTag<tag_type, tag> ttag, const KeyParameter& param) {
-    if (TypedTag2ValueType<TypedTag<tag_type, tag>>::unionTag != param.value.getTag()) return {};
+    // We only check if the parameter has the correct tag here; accessTagValue checks if the correct
+    // union field was initialized.
+    if (tag != param.tag) return {};
     return accessTagValue(ttag, param);
 }