svn commit: r221515 - stable/8/bin/sh

[Jilles Tjoelker]

Author: jilles
Date: Thu May  5 22:07:02 2011
New Revision: 221515
URL: http://svn.freebsd.org/changeset/base/221515

Log:
  MFC r221012: sh: Check setuid()/setgid() return values.
  
  If the -p option is turned off, privileges from a setuid or setgid binary
  are dropped. Make sure to check if this succeeds. If it fails, this is an
  error which will cause the shell to abort except in interactive mode or if
  'command' was used to make 'set' or an outer 'eval' or '.' non-special.
  
  Note that taking advantage of this feature and writing setuid shell scripts
  seems unwise.

Modified:
  stable/8/bin/sh/options.c
Directory Properties:
  stable/8/bin/sh/   (props changed)

Modified: stable/8/bin/sh/options.c
==============================================================================
--- stable/8/bin/sh/options.c	Thu May  5 22:04:59 2011	(r221514)
+++ stable/8/bin/sh/options.c	Thu May  5 22:07:02 2011	(r221515)
@@ -278,8 +278,10 @@ setoption(int flag, int val)
 	int i;
 
 	if (flag == 'p' && !val && privileged) {
-		(void) setuid(getuid());
-		(void) setgid(getgid());
+		if (setgid(getgid()) == -1)
+			error("setgid");
+		if (setuid(getuid()) == -1)
+			error("setuid");
 	}
 	for (i = 0; i < NOPTS; i++)
 		if (optlist[i].letter == flag) {