Clear collected_seed after freeing it

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9662)

diff --git a/crypto/evp/pkey_kdf.c b/crypto/evp/pkey_kdf.c
index f4cf40e6f4bde12094a6656109c14a7924b5e0d3..c13bb203b3fc7beff05a32f13c5ccbb7a14ff519 100644 (file)
--- a/crypto/evp/pkey_kdf.c
+++ b/crypto/evp/pkey_kdf.c
@@ -127,8 +127,10 @@ static int pkey_kdf_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
          * Perform the semantics described in
          * EVP_PKEY_CTX_add1_tls1_prf_seed(3)
          */
-        if (ctx->pmeth->pkey_id == NID_tls1_prf)
+        if (ctx->pmeth->pkey_id == NID_tls1_prf) {
             BUF_MEM_free(pkctx->collected_seed);
+            pkctx->collected_seed = NULL;
+        }
         break;
     case EVP_PKEY_CTRL_TLS_SEED:
         cmd = T_OCTET_STRING;