svn commit: r265095 - head/lib/libc/locale

[Pedro F. Giffuni]

Author: pfg
Date: Tue Apr 29 15:25:57 2014
New Revision: 265095
URL: http://svnweb.freebsd.org/changeset/base/265095

Log:
  citrus: Avoid invalid code points.
  
  From the OpenBSD log:
  The UTF-8 decoder should not accept byte sequences which decode to unicode
  code positions U+D800 to U+DFFF (UTF-16 surrogates), U+FFFE, and U+FFFF.
  
  http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
  http://unicode.org/faq/utf_bom.html#utf8-4
  
  Reported by:	Stefan Sperling
  Obtained from:	OpenBSD
  MFC after:	5 days

Modified:
  head/lib/libc/locale/utf8.c

Modified: head/lib/libc/locale/utf8.c
==============================================================================
--- head/lib/libc/locale/utf8.c	Tue Apr 29 15:12:23 2014	(r265094)
+++ head/lib/libc/locale/utf8.c	Tue Apr 29 15:25:57 2014	(r265095)
@@ -203,6 +203,14 @@ _UTF8_mbrtowc(wchar_t * __restrict pwc, 
 		errno = EILSEQ;
 		return ((size_t)-1);
 	}
+	if ((wch >= 0xd800 && wch <= 0xdfff) ||
+	    wch == 0xfffe || wch == 0xffff) {
+		/*
+		 * Malformed input; invalid code points.
+		 */
+		errno = EILSEQ;
+		return ((size_t)-1);
+	}
 	if (pwc != NULL)
 		*pwc = wch;
 	us->want = 0;