openssl: check return value of X509_get0_pubkey

Fixes #16468
Closes #16469

diff --git a/lib/vtls/openssl.c b/lib/vtls/openssl.c
index 3816ce14e90225bc9cfac152bd6f16367c8e89cd..c7d84291c75f8e9e72638179e72e1f0c2afae170 100644 (file)
--- a/lib/vtls/openssl.c
+++ b/lib/vtls/openssl.c
@@ -4532,7 +4532,7 @@ static void infof_certstack(struct Curl_easy *data, const SSL *ssl)
                                                sizeof(group_name), NULL);
       msnprintf(group_name_final, sizeof(group_name_final), "/%s", group_name);
     }
-    type_name = EVP_PKEY_get0_type_name(current_pkey);
+    type_name = current_pkey ? EVP_PKEY_get0_type_name(current_pkey) : NULL;
 #else
     get_group_name = 0;
     type_name = NULL;