From: Alan T. DeKok <aland@freeradius.org>
Date: Mon, 6 Dec 2021 20:24:16 +0000 (-0500)
Subject: catch stupidities.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=23c0684803581391e69f737fcd7c0e42464ba9ef;p=thirdparty%2Ffreeradius-server.git

catch stupidities.

A ^= A is wrong
A .= A is wrong
A UNION A --> A
A MERGE A --> A
A := A    --> A
---

diff --git a/src/lib/util/edit.c b/src/lib/util/edit.c
index 87765e45ee..b910200249 100644
--- a/src/lib/util/edit.c
+++ b/src/lib/util/edit.c
@@ -867,21 +867,37 @@ int fr_edit_list_apply_list_assignment(fr_edit_list_t *el, fr_pair_t *dst, fr_to
 		 *	new list.
 		 */
 	case T_OP_SET:
+		if (&dst->children == src) return 0; /* A := A == A */
+
 		if (fr_edit_list_free_pair_children(el, dst) < 0) return -1;
 		FALL_THROUGH;
 
 	case T_OP_ADD_EQ:
+		if (&dst->children == src) {
+			fr_strerror_printf("Cannot append list to itself");
+			return -1;
+		}
+
 		COPY;
 		return fr_edit_list_insert_list_tail(el, &dst->children, &copy);
 
 	case T_OP_PREPEND:
+		if (&dst->children == src) {
+			fr_strerror_printf("Cannot prepend list to itself");
+			return -1;
+		}
+
 		COPY;
 		return fr_edit_list_insert_list_head(el, &dst->children, &copy);
 
 	case T_OP_OR_EQ:
+		if (&dst->children == src) return 0; /* A UNION A == A */
+
 		return list_union(el, dst, src);
 
 	case T_OP_GE:
+		if (&dst->children == src) return 0; /* A MERGE A == A */
+
 		return list_merge_lhs(el, dst, src);
 
 	default: