Integrating comments

src/protocols/secure_channel/PASESession.cpp

@@ -232,18 +232,15 @@ CHIP_ERROR PASESession::Pair(SessionManager & sessionManager, uint32_t peerSetUp
 exit:
     if (err != CHIP_NO_ERROR)
     {
-        // If a failure happens in PASESession::Init, we need to ensure that the passed exchange context is closed to prevent
-        // resource leaks.
-        exchangeCtxt->Close();
-
-        // If a failure happens in SendPBKDFParamRequest, we need to Discard the exchange (mExchangeCtxt) so that Clear() doesn't
-        // try closing it.  The exchange will handle that.
-        DiscardExchange();
+        // If a failure happens before we have placed the incoming exchange into `mExchangeCtxt`, we need to make
+        // sure to close the exchange to fulfill our API contract.
+        if (!mExchangeCtxt.HasValue())
+        {
+            exchangeCtxt->Close();
+        }
         Clear();
         ChipLogError(SecureChannel, "Failed during PASE session pairing request: %" CHIP_ERROR_FORMAT, err.Format());
         MATTER_TRACE_COUNTER("PASEFail");
-        // Do this last in case the delegate frees us.
-        NotifySessionEstablishmentError(err);
     }
     return err;
 }