super unchecked setuid (CVE-2014-0470)

[Florian Weimer <fw () deneb enyo de>]

Robert's patch, reproduced below, has all the details.

From: Robert Luberda <robert () debian org>
Date: Wed, 23 Apr 2014 00:28:19 +0200
Subject: 14 Fix unchecked setuid call

Fix the following issue noticed by John Lightsey:
  super.c does an unchecked setuid(getuid()) when the -F flag
  is supplied pointing to a configuration file to test. This opens
  super up to the RLIM_NPROC style exploits on 2.6 kernels.

The issue was assigned number CVE-2014-0470.
---
 super.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/super.c b/super.c
index abea061..1c21886 100644
--- a/super.c
+++ b/super.c
@@ -849,7 +849,9 @@ by `-o %s' is overridden by file `%s'", *o_file, superfile);
                     * to the real uid.
                     */
                    if (getuid() != 0) {
-                       setuid(getuid());
+                       if (setuid(getuid()) == -1)
+                           Error(1, 1, "Can't set uid to %d: ", getuid());
+
                        fprintf(stderr,
     "\t** Since you have supplied a super.tab file that isn't the default,\n");
                        fprintf(stderr,