diff --git a/security/manager/ssl/src/nsCrypto.cpp b/security/manager/ssl/src/nsCrypto.cpp
index f1c11bb07e16..d08895013a8c 100644
--- a/security/manager/ssl/src/nsCrypto.cpp
+++ b/security/manager/ssl/src/nsCrypto.cpp
@@ -696,6 +696,10 @@ cryptojs_generateOneKeyPair(JSContext *cx, nsKeyPairInfo *keyPairInfo,
                                                      (params) ? strlen(params):0, 
                                                      keySize, keyPairInfo);
 
+  if (!keyGenParams) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
   // Make sure the token has password already set on it before trying
   // to generate the key.