Fix insecure tempfile usage

http://bugs.gentoo.org/105000

--- flexbackup
+++ flexbackup
@@ -269,6 +269,7 @@ if (($::mode !~ m/^(list|extract|restore
     untie(%::index);
 }
 
+system ('rm', '-rf', $cfg::tmpdir) if (defined($cfg::deltmpdir));
 exit(0);
 
 ######################################################################
@@ -2725,6 +2726,13 @@ sub optioncheck {
     &checkvar(\$cfg::prefix,'prefix','exist','');
     &checkvar(\$cfg::sprefix,'sprefix','exist','');
 
+    # Create a subdirectory inside /tmp
+    if ($cfg::tmpdir eq '/tmp') {
+       $cfg::tmpdir = $cfg::tmpdir .'/'.$$;
+       mkdir ($cfg::tmpdir) || die "Can't create temporary directory, $!";
+       $cfg::deltmpdir = 1;
+    }
+
     if (@::errors) {
 	print $::msg "Errors:\n";
 	while(@::errors) {
@@ -5236,8 +5244,8 @@ sub test_bufferprog {
     # Create a script which tests the buffer program
     open(SCR,"> $tmp_script") || die;
     print SCR "#!/bin/sh\n";
-    print SCR "tmp_data=/tmp/bufftest\$\$.txt\n";
-    print SCR "tmp_err=/tmp/bufftest\$\$.err\n";
+    print SCR "tmp_data=\`tempfile\`\n";
+    print SCR "tmp_err=\`tempfile\`\n";
     print SCR "echo testme > \$tmp_data\n";
     print SCR "$buffer_cmd > /dev/null 2> \$tmp_err < \$tmp_data\n";
     print SCR "res=\$?\n";