[NetLabel]: correct improper handling of non-NetLabel peer contexts

Fix a problem where NetLabel would always set the value of 
sk_security_struct->peer_sid in selinux_netlbl_sock_graft() to the context of
the socket, causing problems when users would query the context of the
connection.  This patch fixes this so that the value in
sk_security_struct->peer_sid is only set when the connection is NetLabel based,
otherwise the value is untouched.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 80a2a09..a3bae2c 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -1486,6 +1486,54 @@
 }
 
 /**
+ * cipso_v4_sock_getattr - Get the security attributes from a sock
+ * @sk: the sock
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Query @sk to see if there is a CIPSO option attached to the sock and if
+ * there is return the CIPSO security attributes in @secattr.  This function
+ * requires that @sk be locked, or privately held, but it does not do any
+ * locking itself.  Returns zero on success and negative values on failure.
+ *
+ */
+int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr)
+{
+	int ret_val = -ENOMSG;
+	struct inet_sock *sk_inet;
+	unsigned char *cipso_ptr;
+	u32 doi;
+	struct cipso_v4_doi *doi_def;
+
+	sk_inet = inet_sk(sk);
+	if (sk_inet->opt == NULL || sk_inet->opt->cipso == 0)
+		return -ENOMSG;
+	cipso_ptr = sk_inet->opt->__data + sk_inet->opt->cipso -
+		sizeof(struct iphdr);
+	ret_val = cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr);
+	if (ret_val == 0)
+		return ret_val;
+
+	doi = ntohl(*(u32 *)&cipso_ptr[2]);
+	rcu_read_lock();
+	doi_def = cipso_v4_doi_getdef(doi);
+	if (doi_def == NULL) {
+		rcu_read_unlock();
+		return -ENOMSG;
+	}
+	switch (cipso_ptr[6]) {
+	case CIPSO_V4_TAG_RBITMAP:
+		ret_val = cipso_v4_parsetag_rbm(doi_def,
+						&cipso_ptr[6],
+						secattr);
+		break;
+	}
+	rcu_read_unlock();
+
+	return ret_val;
+}
+
+/**
  * cipso_v4_socket_getattr - Get the security attributes from a socket
  * @sock: the socket
  * @secattr: the security attributes
@@ -1499,42 +1547,12 @@
 int cipso_v4_socket_getattr(const struct socket *sock,
 			    struct netlbl_lsm_secattr *secattr)
 {
-	int ret_val = -ENOMSG;
-	struct sock *sk;
-	struct inet_sock *sk_inet;
-	unsigned char *cipso_ptr;
-	u32 doi;
-	struct cipso_v4_doi *doi_def;
+	int ret_val;
 
-	sk = sock->sk;
-	lock_sock(sk);
-	sk_inet = inet_sk(sk);
-	if (sk_inet->opt == NULL || sk_inet->opt->cipso == 0)
-		goto socket_getattr_return;
-	cipso_ptr = sk_inet->opt->__data + sk_inet->opt->cipso -
-		sizeof(struct iphdr);
-	ret_val = cipso_v4_cache_check(cipso_ptr, cipso_ptr[1], secattr);
-	if (ret_val == 0)
-		goto socket_getattr_return;
+	lock_sock(sock->sk);
+	ret_val = cipso_v4_sock_getattr(sock->sk, secattr);
+	release_sock(sock->sk);
 
-	doi = ntohl(*(u32 *)&cipso_ptr[2]);
-	rcu_read_lock();
-	doi_def = cipso_v4_doi_getdef(doi);
-	if (doi_def == NULL) {
-		rcu_read_unlock();
-		goto socket_getattr_return;
-	}
-	switch (cipso_ptr[6]) {
-	case CIPSO_V4_TAG_RBITMAP:
-		ret_val = cipso_v4_parsetag_rbm(doi_def,
-						&cipso_ptr[6],
-						secattr);
-		break;
-	}
-	rcu_read_unlock();
-
-socket_getattr_return:
-	release_sock(sk);
 	return ret_val;
 }
 
diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c
index 0fd8aaa..54fb7de 100644
--- a/net/netlabel/netlabel_kapi.c
+++ b/net/netlabel/netlabel_kapi.c
@@ -85,6 +85,29 @@
 }
 
 /**
+ * netlbl_sock_getattr - Determine the security attributes of a sock
+ * @sk: the sock
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Examines the given sock to see any NetLabel style labeling has been
+ * applied to the sock, if so it parses the socket label and returns the
+ * security attributes in @secattr.  Returns zero on success, negative values
+ * on failure.
+ *
+ */
+int netlbl_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr)
+{
+	int ret_val;
+
+	ret_val = cipso_v4_sock_getattr(sk, secattr);
+	if (ret_val == 0)
+		return 0;
+
+	return netlbl_unlabel_getattr(secattr);
+}
+
+/**
  * netlbl_socket_getattr - Determine the security attributes of a socket
  * @sock: the socket
  * @secattr: the security attributes