selinux: Fix the NetLabel glue code for setsockopt()

At some point we (okay, I) managed to break the ability for users to use the
setsockopt() syscall to set IPv4 options when NetLabel was not active on the
socket in question.  The problem was noticed by someone trying to use the
"-R" (record route) option of ping:

 # ping -R 10.0.0.1
 ping: record route: No message of desired type

The solution is relatively simple, we catch the unlabeled socket case and
clear the error code, allowing the operation to succeed.  Please note that we
still deny users the ability to override IPv4 options on socket's which have
NetLabel labeling active; this is done to ensure the labeling remains intact.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>

diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c
index f58701a7b728619a5a50e3bc74981baa23ab60cf..3f4b26647386f58d5932e8e1b78f0e57f8752bf6 100644 (file)
--- a/security/selinux/netlabel.c
+++ b/security/selinux/netlabel.c
@@ -490,8 +490,10 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock,
                lock_sock(sk);
                rc = netlbl_sock_getattr(sk, &secattr);
                release_sock(sk);
-               if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
+               if (rc == 0)
                        rc = -EACCES;
+               else if (rc == -ENOMSG)
+                       rc = 0;
                netlbl_secattr_destroy(&secattr);
        }