crypto: avoid double free

mhdawson · targos · commit adbd92ef1d6b · 2021-10-20T16:54:19.000+02:00
Coverity scan reported a free after use and I think its right. Tweak to avoid double free. Signed-off-by: Michael Dawson <mdawson@devrus.com> PR-URL: #40380 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Luigi Pinca <luigipinca@gmail.com> Reviewed-By: Minwoo Jung <nodecorelab@gmail.com> Reviewed-By: Darshan Sen <raisinten@gmail.com>
diff --git a/src/crypto/crypto_util.h b/src/crypto/crypto_util.h
@@ -550,9 +550,12 @@ struct EnginePointer {
 
   inline void reset(ENGINE* engine_ = nullptr, bool finish_on_exit_ = false) {
     if (engine != nullptr) {
-      if (finish_on_exit)
-        ENGINE_finish(engine);
-      ENGINE_free(engine);
+      if (finish_on_exit) {
+        // This also does the equivalent of ENGINE_free.
+        CHECK_EQ(ENGINE_finish(engine), 1);
+      } else {
+        CHECK_EQ(ENGINE_free(engine), 1);
+      }
     }
     engine = engine_;
     finish_on_exit = finish_on_exit_;
