Audit malloc(3)/calloc(3)/realloc(3) usage.

* Change eight reallocs to reallocarray to be safe from overflows.
* Change one malloc to reallocarray to be safe from overflows.
* Change one calloc to reallocarray, no zeroing needed.
* Change the order of arguments of three callocs (aesthetical).

1 files changed, 45 insertions, 0 deletions

diff --git a/compat_reallocarray.c b/compat_reallocarray.c
new file mode 100644
index 00000000..e25d8374
--- /dev/null
+++ b/compat_reallocarray.c
@@ -0,0 +1,45 @@
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifdef HAVE_REALLOCARRAY
+
+int dummy;
+
+#else
+
+/*	$OpenBSD: malloc.c,v 1.158 2014/04/23 15:07:27 tedu Exp $	*/
+/*
+ * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net>
+ *
+ * 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 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 <errno.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#define MUL_NO_OVERFLOW (1UL << (sizeof(size_t) * 4))
+
+void *
+reallocarray(void *optr, size_t nmemb, size_t size)
+{
+	if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
+	    nmemb > 0 && SIZE_MAX / nmemb < size) {
+		errno = ENOMEM;
+		return NULL;
+	}
+	return realloc(optr, size * nmemb);
+}
+
+#endif /*!HAVE_REALLOCARRAY*/