From 7d38a883dae528a0216733b4d831f2f20aa9c04b Mon Sep 17 00:00:00 2001
From: Jeremy Allison <jra@samba.org>
Date: Tue, 9 Jun 2015 12:42:10 -0700
Subject: [PATCH 1/9] CVE-2015-3223: lib: ldb: Cope with canonicalise_fn
 returning string "", length 0.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11325

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
---
 lib/ldb/common/ldb_match.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/lib/ldb/common/ldb_match.c b/lib/ldb/common/ldb_match.c
index a493dae..7414289 100644
--- a/lib/ldb/common/ldb_match.c
+++ b/lib/ldb/common/ldb_match.c
@@ -271,6 +271,14 @@ static int ldb_wildcard_compare(struct ldb_context *ldb,
 		if (cnk.length > val.length) {
 			goto mismatch;
 		}
+		/*
+		 * Empty strings are returned as length 0. Ensure
+		 * we can cope with this.
+		 */
+		if (cnk.length == 0) {
+			goto mismatch;
+		}
+
 		if (memcmp((char *)val.data, (char *)cnk.data, cnk.length) != 0) goto mismatch;
 		val.length -= cnk.length;
 		val.data += cnk.length;
@@ -284,7 +292,13 @@ static int ldb_wildcard_compare(struct ldb_context *ldb,
 		chunk = tree->u.substring.chunks[c];
 		if(a->syntax->canonicalise_fn(ldb, ldb, chunk, &cnk) != 0) goto mismatch;
 
-		/* FIXME: case of embedded nulls */
+		/*
+		 * Empty strings are returned as length 0. Ensure
+		 * we can cope with this.
+		 */
+		if (cnk.length == 0) {
+			goto mismatch;
+		}
 		p = strstr((char *)val.data, (char *)cnk.data);
 		if (p == NULL) goto mismatch;
 		if ( (! tree->u.substring.chunks[c + 1]) && (! tree->u.substring.end_with_wildcard) ) {
-- 
2.5.0