svn commit: r350526 - stable/12/lib/libc/tests/string

[Brooks Davis]

Author: brooks
Date: Thu Aug  1 23:28:54 2019
New Revision: 350526
URL: https://svnweb.freebsd.org/changeset/base/350526

Log:
  MFC r350160:
  
  Avoid copying too much from the input string.
  
  This avoids reading past the end of the static strings.  On a system
  with bounds checking these tests fault.
  
  Reviewed by:	asomers
  Obtained from:	CheriBSD
  Sponsored by:	DARPA, AFRL
  Differential Revision:	https://reviews.freebsd.org/D21004

Modified:
  stable/12/lib/libc/tests/string/wcsnlen_test.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/lib/libc/tests/string/wcsnlen_test.c
==============================================================================
--- stable/12/lib/libc/tests/string/wcsnlen_test.c	Thu Aug  1 22:48:06 2019	(r350525)
+++ stable/12/lib/libc/tests/string/wcsnlen_test.c	Thu Aug  1 23:28:54 2019	(r350526)
@@ -65,7 +65,7 @@ test_wcsnlen(const wchar_t *s)
 	for (i = 0; i <= 1; i++) {
 		for (bufsize = 0; bufsize <= size + 10; bufsize++) {
 			s1 = makebuf(bufsize * sizeof(wchar_t), i);
-			wmemcpy(s1, s, bufsize);
+			wmemcpy(s1, s, bufsize <= size ? bufsize : size);
 			len = (size > bufsize) ? bufsize : size - 1;
 			ATF_CHECK(wcsnlen(s1, bufsize) == len);
 		}