Update imsg*.c from OpenBSD.

compat/freezero.c

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2017 Nicholas Marriott <nicholas.marriott@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "compat.h"
+
+void
+freezero(void *ptr, size_t size)
+{
+	memset(ptr, 0, size);
+	free(ptr);
+}

compat/imsg-buffer.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: imsg-buffer.c,v 1.9 2017/03/17 14:51:26 deraadt Exp $	*/
+/*	$OpenBSD: imsg-buffer.c,v 1.10 2017/04/11 09:57:19 reyk Exp $	*/
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -182,7 +182,7 @@ ibuf_free(struct ibuf *buf)
 {
 	if (buf == NULL)
 		return;
-	free(buf->buf);
+	freezero(buf->buf, buf->size);
 	free(buf);
 }
 

compat/imsg.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: imsg.c,v 1.14 2017/03/24 09:34:12 nicm Exp $	*/
+/*	$OpenBSD: imsg.c,v 1.15 2017/04/11 09:57:19 reyk Exp $	*/
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -263,7 +263,7 @@ imsg_close(struct imsgbuf *ibuf, struct ibuf *msg)
 void
 imsg_free(struct imsg *imsg)
 {
-	free(imsg->data);
+	freezero(imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE);
 }
 
 int

configure.ac

@@ -105,6 +105,7 @@ AC_REPLACE_FUNCS([ \
 	explicit_bzero \
 	fgetln \
 	fparseln \
+	freezero \
 	getdtablecount \
 	getprogname \
 	recallocarray \