Rework handling of the out_kinv and out_r pointers

suggested by jsing

1 files changed, 15 insertions, 8 deletions

diff --git a/src/lib/libcrypto/ecdsa/ecs_ossl.c b/src/lib/libcrypto/ecdsa/ecs_ossl.c
index 17d39cf36d..b8a0344753 100644
--- a/src/lib/libcrypto/ecdsa/ecs_ossl.c
+++ b/src/lib/libcrypto/ecdsa/ecs_ossl.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ecs_ossl.c,v 1.42 2023/07/02 13:05:29 tb Exp $ */
+/* $OpenBSD: ecs_ossl.c,v 1.43 2023/07/02 13:18:54 tb Exp $ */
 /*
  * Written by Nils Larsch for the OpenSSL project
  */
@@ -130,6 +130,12 @@ ossl_ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *in_ctx, BIGNUM **out_kinv,
         const EC_GROUP *group;
         int order_bits, ret = 0;
 
+        BN_free(*out_kinv);
+        *out_kinv = NULL;
+
+        BN_free(*out_r);
+        *out_r = NULL;
+
         if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) {
                 ECDSAerror(ERR_R_PASSED_NULL_PARAMETER);
                 return 0;
@@ -220,20 +226,21 @@ ossl_ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *in_ctx, BIGNUM **out_kinv,
                 ECDSAerror(ERR_R_BN_LIB);
                 goto err;
         }
-        BN_free(*out_r);
-        BN_free(*out_kinv);
-        *out_r = r;
+
         *out_kinv = k;
+        k = NULL;
+
+        *out_r = r;
+        r = NULL;
+
         ret = 1;
 
  err:
-        if (ret == 0) {
-                BN_free(k);
-                BN_free(r);
-        }
         if (in_ctx == NULL)
                 BN_CTX_free(ctx);
         BN_free(order);
+        BN_free(k);
+        BN_free(r);
         EC_POINT_free(point);
         BN_free(x);
         return (ret);