Expression evaluation: treat null expression as unconditional, not segfault.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@644105 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/server/util_expr.c b/server/util_expr.c
index fd1fd99424282101541002b9257ed4f6d1dff13b..a9a6640e6aa91b02d0324eb2ce0fd0b0c3dcbe6a 100644 (file)
--- a/server/util_expr.c
+++ b/server/util_expr.c
@@ -871,7 +871,11 @@ AP_DECLARE(int) ap_expr_eval(request_rec *r, ap_parse_node_t *root,
                              int *was_error, backref_t **reptr,
                              string_func_t string_func, opt_func_t eval_func)
 {
-    ap_parse_node_t *clone = ap_expr_clone_tree(r->pool, root, NULL);
+    ap_parse_node_t *clone;
+    if (root == NULL) {  /* no condition == unconditional */
+        return 1;
+    }
+    clone = ap_expr_clone_tree(r->pool, root, NULL);
     return expr_eval(r, clone, was_error, reptr, string_func, eval_func);
 }
 AP_DECLARE(int) ap_expr_evalstring(request_rec *r, const char *expr,