From 77860ba866882a6ec65f57378ca64419d14de72e Mon Sep 17 00:00:00 2001
From: Steffen Jaeckel <s@jaeckel.eu>
Date: Fri, 4 May 2012 01:01:24 +0200
Subject: [PATCH] yarrow: prevent access to NULL pointer

---
 src/prngs/yarrow.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/prngs/yarrow.c b/src/prngs/yarrow.c
index b5cced38..d6566e6e 100644
--- a/src/prngs/yarrow.c
+++ b/src/prngs/yarrow.c
@@ -343,11 +343,13 @@ int yarrow_test(void)
    }
 
    /* now let's test the hash/cipher that was chosen */
-   if ((err = cipher_descriptor[prng.yarrow.cipher].test()) != CRYPT_OK) {
-      return err; 
+   if (cipher_descriptor[prng.yarrow.cipher].test &&
+       ((err = cipher_descriptor[prng.yarrow.cipher].test()) != CRYPT_OK)) {
+      return err;
    }
-   if ((err = hash_descriptor[prng.yarrow.hash].test()) != CRYPT_OK) {
-      return err; 
+   if (hash_descriptor[prng.yarrow.hash].test &&
+       ((err = hash_descriptor[prng.yarrow.hash].test()) != CRYPT_OK)) {
+      return err;
    }
 
    return CRYPT_OK;