paste -d\\: avoid heap overrun for backslash at end of delim list

* src/paste.c: Include "quotearg.h".
(collapse_escapes): Handle backslash-escaped backslash explicitly.
Handle unescaped backslash at end of string by returning nonzero,
rather than by overrunning memory.
(main): Diagnose an invalid delimiter list -- carefully.
Reported by Cristian Cadar, Daniel Dunbar and Dawson Engler.
* tests/misc/paste-no-nl (delim-bs): Add a test to demonstrate the
heap-smashing capability.
(delim-bs2): Prior to coreutils-5.1.2, this bug was a little harder
to demonstrate: it would corrupt a first-argument containing e.g., \b
* NEWS: Mention the bug fix.
* tests/misc/Makefile.am (TESTS): Reflect renaming.
* tests/misc/paste: Rename from paste-no-nl.

Signed-off-by: Jim Meyering <meyering@redhat.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/tests/misc/paste b/tests/misc/paste
new file mode 100755
index 000000000..ab923a22a
--- /dev/null
+++ b/tests/misc/paste
@@ -0,0 +1,74 @@
+#!/bin/sh
+# -*- perl -*-
+# Test paste.
+
+# Copyright (C) 2003, 2005, 2007-2008 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+: ${srcdir=.}
+. $srcdir/../require-perl
+
+me=`echo $0|sed 's,.*/,,'`
+exec $PERL -w -I$srcdir/.. -MCoreutils -M"CuTmpdir qw($me)" -- - <<\EOF
+#/
+require 5.003;
+use strict;
+
+(my $program_name = $0) =~ s|.*/||;
+
+# Turn off localization of executable's ouput.
+@ENV{qw(LANGUAGE LANG LC_ALL)} = ('C') x 3;
+
+my $prog = 'paste';
+my $msg = "$prog: delimiter list ends with an unescaped backslash: ";
+
+my @Tests =
+  (
+   # Ensure that paste properly handles files lacking a final newline.
+   ['no-nl-1', {IN=>"a"},   {IN=>"b"},   {OUT=>"a\tb\n"}],
+   ['no-nl-2', {IN=>"a\n"}, {IN=>"b"},   {OUT=>"a\tb\n"}],
+   ['no-nl-3', {IN=>"a"},   {IN=>"b\n"}, {OUT=>"a\tb\n"}],
+   ['no-nl-4', {IN=>"a\n"}, {IN=>"b\n"}, {OUT=>"a\tb\n"}],
+
+   # Same as above, but with a two lines in each input file and
+   # the addition of the -d option to make SPACE be the output delimiter.
+   ['no-nla1', '-d" "', {IN=>"1\na"},   {IN=>"2\nb"},   {OUT=>"1 2\na b\n"}],
+   ['no-nla2', '-d" "', {IN=>"1\na\n"}, {IN=>"2\nb"},   {OUT=>"1 2\na b\n"}],
+   ['no-nla3', '-d" "', {IN=>"1\na"},   {IN=>"2\nb\n"}, {OUT=>"1 2\na b\n"}],
+   ['no-nla4', '-d" "', {IN=>"1\na\n"}, {IN=>"2\nb\n"}, {OUT=>"1 2\na b\n"}],
+
+   # Specifying a delimiter with a trailing backslash would overrun a
+   # malloc'd buffer.
+   ['delim-bs1', q!-d'\'!, {IN=>{'a'x50=>''}}, {EXIT => 1},
+    # We print a single backslash into the expected output, so need four
+    # (two, each escaped) here.
+    {ERR => $msg . q!\\\\! . "\n"} ],
+
+   # Prior to coreutils-5.1.2, this sort of abuse would make paste
+   # scribble on command-line arguments.  With paste from coreutils-5.1.0,
+   # this example would mangle the first file name argument, if it contains
+   # accepted backslash-escapes:
+   # $ paste -d\\ '123\b\b\b.....@' 2>&1 |cat -A
+   # paste: 23^H^H^H.....@...@: No such file or directory$
+   ['delim-bs2', q!-d'\'!, {IN=>{'123\b\b\b.....@'=>''}}, {EXIT => 1},
+    {ERR => $msg . q!\\\\! . "\n"} ],
+  );
+
+my $save_temps = $ENV{DEBUG};
+my $verbose = $ENV{VERBOSE};
+
+my $fail = run_tests ($program_name, $prog, \@Tests, $save_temps, $verbose);
+exit $fail;
+EOF