From: Stefan Metzmacher <metze@samba.org>
Date: Thu, 16 Mar 2023 08:57:43 +0000 (+0100)
Subject: CVE-2023-4154 replace: add ARRAY_INSERT_ELEMENT() helper
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b59a4266f1b17d9aaf1485b09db15b911b470228;p=thirdparty%2Fsamba.git

CVE-2023-4154 replace: add ARRAY_INSERT_ELEMENT() helper

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15424

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>

(cherry picked from commit 9d8ff0d1e0b2ba7c84af36e1931f5bc99902a44b)
---

diff --git a/lib/replace/replace.h b/lib/replace/replace.h
index bd7f6e53e81..bcd5c09bf7c 100644
--- a/lib/replace/replace.h
+++ b/lib/replace/replace.h
@@ -889,6 +889,21 @@ typedef unsigned long long ptrdiff_t ;
 #define ARRAY_DEL_ELEMENT(a,i,n) \
 if((i)<((n)-1)){memmove(&((a)[(i)]),&((a)[(i)+1]),(sizeof(*(a))*((n)-(i)-1)));}
 
+/**
+ * Insert an array element by moving the rest one up
+ *
+ */
+#define ARRAY_INSERT_ELEMENT(__array,__old_last_idx,__new_elem,__new_idx) do { \
+	if ((__new_idx) < (__old_last_idx)) { \
+		const void *__src = &((__array)[(__new_idx)]); \
+		void *__dst = &((__array)[(__new_idx)+1]); \
+		size_t __num = (__old_last_idx)-(__new_idx); \
+		size_t __len = sizeof(*(__array)) * __num; \
+		memmove(__dst, __src, __len); \
+	} \
+	(__array)[(__new_idx)] = (__new_elem); \
+} while(0)
+
 /**
  * Pointer difference macro
  */