dpkg: Security Advisory - CVE-2014-3127

commit a12eb58959d0a10584a428f4a3103a49204c410f upstream

dpkg 1.15.9 on Debian squeeze introduces support for the "C-style
encoded filenames" feature without recognizing that the squeeze patch
program lacks this feature, which triggers an interaction error that
allows remote attackers to conduct directory traversal attacks and
modify files outside of the intended directories via a crafted source
package.

NOTE: this can be considered a release engineering problem in the
effort to fix CVE-2014-0471.

Upstream-Status: Backport

Signed-off-by: Wenlin Kang <wenlin.kang@windriver.com>
Signed-off-by: Wenzong Fan <wenzong.fan@windriver.com>
=====================================================
diff -uarN dpkg-1.17.1-org/scripts/Dpkg/Source/Patch.pm dpkg-1.17.1/scripts/Dpkg/Source/Patch.pm
--- dpkg-1.17.1-org/scripts/Dpkg/Source/Patch.pm	2014-06-05 16:32:41.765446564 +0800
+++ dpkg-1.17.1/scripts/Dpkg/Source/Patch.pm	2014-06-05 16:37:21.461446359 +0800
@@ -324,31 +324,6 @@
     return $line;
 }
 
-my %ESCAPE = ((
-    'a' => "\a",
-    'b' => "\b",
-    'f' => "\f",
-    'n' => "\n",
-    'r' => "\r",
-    't' => "\t",
-    'v' => "\cK",
-    '\\' => '\\',
-    '"' => '"',
-), (
-    map { sprintf('%03o', $_) => chr($_) } (0..255)
-));
-
-sub _unescape {
-    my ($diff, $str) = @_;
-
-    if (exists $ESCAPE{$str}) {
-        return $ESCAPE{$str};
-    } else {
-        error(_g('diff %s patches file with unknown escape sequence \\%s'),
-              $diff, $str);
-    }
-}
-
 # Fetch the header filename ignoring the optional timestamp
 sub _fetch_filename {
     my ($diff, $header) = @_;
@@ -358,12 +333,7 @@
 
     # Is it a C-style string?
     if ($header =~ m/^"/) {
-        $header =~ m/^"((?:[^\\"]|\\.)*)"/;
-        error(_g('diff %s patches file with unbalanced quote'), $diff)
-            unless defined $1;
-
-        $header = $1;
-        $header =~ s/\\([0-3][0-7]{2}|.)/_unescape($diff, $1)/eg;
+	error(_g('diff %s patches file with C-style encoded filename'), $diff);
     } else {
         # Tab is the official separator, it's always used when
         # filename contain spaces. Try it first, otherwise strip on space