[DO NOT MERGE] Fix heap buffer overflow for releaseSecureStops. am: fa237c4f76

Change-Id: If5a392a28c53986f4c1bf69004b1bb83186382f0
diff --git a/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp b/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
index 71bb218..aab475e 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
+++ b/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
@@ -818,6 +818,12 @@
     // and the drm service. The clearkey implementation consists of:
     //    count - number of secure stops
     //    list of fixed length secure stops
+    size_t countBufferSize = sizeof(uint32_t);
+    if (input.size() < countBufferSize) {
+        // SafetyNet logging
+        android_errorWriteLog(0x534e4554, "144766455");
+        return Status::BAD_VALUE;
+    }
     uint32_t count = 0;
     sscanf(reinterpret_cast<char*>(input.data()), "%04" PRIu32, &count);