x509: Handle ossl_policy_level_add_node errors

The invocation of ossl_policy_level_add_node in tree_calculate_user_set
did not have any error handling. Add it to prevent a memory leak for the
allocated extra policy data.

Also add error handling to sk_X509_POLICY_NODE_push to ensure that if
a new node was allocated, but could not be added to the stack, it is
freed correctly.

Fix error handling if tree->user_policies cannot be allocated by
returning 0, indicating failure, rather than 1.

Signed-off-by: Clemens Lang <[email protected]>

crypto/x509v3/pcy_tree.c

@@ -25,6 +25,8 @@
 # define OPENSSL_POLICY_TREE_NODES_MAX 1000
 #endif
 
+static void exnode_free(X509_POLICY_NODE *node);
+
 /*
  * Enable this to print out the complete policy tree at various point during
  * evaluation.
@@ -572,15 +574,24 @@ static int tree_calculate_user_set(X509_POLICY_TREE *tree,
  extra->qualifier_set = anyPolicy->data->qualifier_set;
  extra->flags = POLICY_DATA_FLAG_SHARED_QUALIFIERS
  | POLICY_DATA_FLAG_EXTRA_NODE;
- node = level_add_node(NULL, extra, anyPolicy->parent, tree, 1);
+ node = level_add_node(NULL, extra, anyPolicy->parent,
+ tree, 1);
+ if (node == NULL) {
+ policy_data_free(extra);
+ return 0;
+ }
  }
  if (!tree->user_policies) {
  tree->user_policies = sk_X509_POLICY_NODE_new_null();
- if (!tree->user_policies)
- return 1;
+ if (!tree->user_policies) {
+ exnode_free(node);
+ return 0;
+ }
  }
- if (!sk_X509_POLICY_NODE_push(tree->user_policies, node))
+ if (!sk_X509_POLICY_NODE_push(tree->user_policies, node)) {
+ exnode_free(node);
  return 0;
+ }
  }
  return 1;
 }