r16086: Ensure we can never dereference NULL pointers, and that describe what

these two DN comparison functions do.

Andrew Bartlett
(This used to be commit 733b64a733779daade7d1cabbacac2275564b697)

1 files changed, 14 insertions, 7 deletions

diff --git a/source4/lib/ldb/common/ldb_dn.c b/source4/lib/ldb/common/ldb_dn.c
index 9f3374bceb..b90d3d8c9b 100644
--- a/source4/lib/ldb/common/ldb_dn.c
+++ b/source4/lib/ldb/common/ldb_dn.c
@@ -478,23 +478,25 @@ failed:
 	return NULL;
 }
 
-/* compare DNs using casefolding compare functions */
+/* Determine if dn is below base, in the ldap tree.  Used for
+ * evaluating a subtree search.
+ * 0 if they match, otherwise non-zero
+ */
 
 int ldb_dn_compare_base(struct ldb_context *ldb,
-		   const struct ldb_dn *base,
-		   const struct ldb_dn *dn)
+			const struct ldb_dn *base,
+			const struct ldb_dn *dn)
 {
 	int ret;
 	int n0, n1;
 
+	if (base == NULL || base->comp_num == 0) return 0;
+	if (dn == NULL || dn->comp_num == 0) return -1;
+
 	if (base->comp_num > dn->comp_num) {
 		return (dn->comp_num - base->comp_num);
 	}
 
-	if (base == NULL || base->comp_num == 0) return 0;
-	if (dn == NULL || dn->comp_num == 0) return -1;
-	if (base->comp_num > dn->comp_num) return -1;
-
 	/* if the number of components doesn't match they differ */
 	n0 = base->comp_num - 1;
 	n1 = dn->comp_num - 1;
@@ -522,6 +524,11 @@ int ldb_dn_compare_base(struct ldb_context *ldb,
 	return 0;
 }
 
+/* compare DNs using casefolding compare functions.  
+
+   If they match, then return 0
+ */
+
 int ldb_dn_compare(struct ldb_context *ldb,
 		   const struct ldb_dn *edn0,
 		   const struct ldb_dn *edn1)