Re: [PATCH, local root on 2.4, 2.6?] compute_creds race

[Olaf Dietsche <olaf+list.linux-kernel@olafdietsche.de>]

Andy Lutomirski <luto@myrealbox.com> writes:

> The setuid program is now running with uid=euid=500 but full permitted
> capabilities.  There are two (or three) ways to effectively get local
> root now:

What about this slightly shorter fix?

diff -urN a/fs/exec.c b/fs/exec.c
--- a/fs/exec.c	Fri Mar 12 01:19:06 2004
+++ b/fs/exec.c	Sat Apr 10 10:54:20 2004
@@ -942,6 +942,9 @@
 			if(!capable(CAP_SETUID)) {
 				bprm->e_uid = current->uid;
 				bprm->e_gid = current->gid;
+				cap_clear (bprm->cap_inheritable);
+				cap_clear (bprm->cap_permitted);
+				cap_clear (bprm->cap_effective);
 			}
 		}
 	}

Regards, Olaf.