gitweb: Sanitize title attribute in format_subject_html

Replace control characters with question mark '?' (like in chop_and_esc_str). A little background: some web browsers turn on strict (and unforgiving) XML validating mode for XHTML documents served using application/xhtml+xml content type. This means among others that control characters are forbidden to appear in gitweb output. CGI.pm does by default slight escaping (using simple_escape subroutine from CGI::Util) of all _attribute_ values (depending on the value of autoEscape, by default on). This escaping, at least in CGI.pm version 3.10 (most current version at CPAN is 3.43), is minimal: only '"', '&', '<' and '>' are escaped using named HTML entity references (", &, < and > respectively). But simple_escape does not do escaping of control characters such as ^X which are invalid in XHTML (in strict mode). If by some accident commit message do contain some control character in first 50 characters (more or less) of first line of commit message, and this line is longer than 50 characters (so gitweb shortens it for display), then gitweb would put this control character in title attribute (and CGI.pm would not remove them). The tag _contents_ is safe because it is escaped using esc_html() explicitly, and it replaces control characters by their printable representation. While at it: chop_and_escape_str doesn't need capturing group. Noticed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jakub Narebski <jnareb@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jakub Narebski committed May 22, 2009 at 17:35 UTC 14afe77486281e411bfadd131e5c8ffc44e22a26

1 file changed +2 -1

gitweb/gitweb.perl

+2 -1

@@ -1235,7 +1235,7 @@ sub chop_and_escape_str {

1235 if ($chopped eq $str) {

1236 return esc_html($chopped);

1237 } else {

1238 - $str =~ s/([[:cntrl:]])/?/g;

1238 + $str =~ s/[[:cntrl:]]/?/g;

1239 return $cgi->span({-title=>$str}, esc_html($chopped));

1240 }

1241 }

@@ -1458,6 +1458,7 @@ sub format_subject_html {

1458 $extra = '' unless defined($extra);

1459

1460 if (length($short) < length($long)) {

1461 + $long =~ s/[[:cntrl:]]/?/g;

1462 return $cgi->a({-href => $href, -class => "list subject",

1463 -title => to_utf8($long)},

1464 esc_html($short) . $extra);