1 files changed, 58 insertions, 0 deletions
diff --git a/lib/libc/secure/vsprintf_chk.c b/lib/libc/secure/vsprintf_chk.c
new file mode 100644
index 000000000000..6855feb92f15
--- /dev/null
+++ b/lib/libc/secure/vsprintf_chk.c
@@ -0,0 +1,58 @@
+/*-
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2006 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Christos Zoulas.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <sys/cdefs.h>
+__RCSID("$NetBSD: vsprintf_chk.c,v 1.6 2009/02/05 05:39:38 lukem Exp $");
+
+#include <limits.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+#include <ssp/stdio.h>
+#undef vsprintf
+#undef vsnprintf
+
+int
+__vsprintf_chk(char * __restrict buf, int flags, size_t slen,
+    const char * __restrict fmt, va_list ap)
+{
+	int rv;
+
+	if (slen > (size_t)INT_MAX)
+		rv = vsprintf(buf, fmt, ap);
+	else {
+		if ((rv = vsnprintf(buf, slen, fmt, ap)) >= 0 &&
+		    (size_t)rv >= slen)
+			__chk_fail();
+	}
+
+	return (rv);
+}