From: Ben Pfaff <blp@cs.stanford.edu>
Date: Mon, 25 Jan 2021 00:30:42 +0000 (-0800)
Subject: str: Avoid passing null pointer to memcpy() in ds_put_substring().
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7b7074fa6baa35e1e04e7943d8b1b7f6c43a49c5;p=pspp

str: Avoid passing null pointer to memcpy() in ds_put_substring().
---

diff --git a/src/libpspp/str.c b/src/libpspp/str.c
index a58473192e..e06f626571 100644
--- a/src/libpspp/str.c
+++ b/src/libpspp/str.c
@@ -1481,7 +1481,8 @@ ds_put_cstr (struct string *st, const char *s)
 void
 ds_put_substring (struct string *st, struct substring ss)
 {
-  memcpy (ds_put_uninit (st, ss_length (ss)), ss_data (ss), ss_length (ss));
+  if (ss.length)
+    memcpy (ds_put_uninit (st, ss_length (ss)), ss_data (ss), ss_length (ss));
 }
 
 /* Returns ds_end(ST) and THEN increases the length by INCR. */