selinux: Fix missing calls to netlbl_skbuff_err()

At some point I think I messed up and dropped the calls to netlbl_skbuff_err()
which are necessary for CIPSO to send error notifications to remote systems.
This patch re-introduces the error handling calls into the SELinux code.

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

5 files changed, 50 insertions, 9 deletions

diff --git a/include/net/netlabel.h b/include/net/netlabel.h
index 5303749b7093..e16db0961265 100644
--- a/include/net/netlabel.h
+++ b/include/net/netlabel.h
@@ -382,7 +382,7 @@ int netlbl_sock_getattr(struct sock *sk,
 int netlbl_skbuff_getattr(const struct sk_buff *skb,
                           u16 family,
                           struct netlbl_lsm_secattr *secattr);
-void netlbl_skbuff_err(struct sk_buff *skb, int error);
+void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway);
 
 /*
  * LSM label mapping cache operations
@@ -454,7 +454,9 @@ static inline int netlbl_skbuff_getattr(const struct sk_buff *skb,
 {
         return -ENOSYS;
 }
-static inline void netlbl_skbuff_err(struct sk_buff *skb, int error)
+static inline void netlbl_skbuff_err(struct sk_buff *skb,
+                                     int error,
+                                     int gateway)
 {
         return;
 }
diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c
index 6c211fe97782..22faba620e4b 100644
--- a/net/netlabel/netlabel_kapi.c
+++ b/net/netlabel/netlabel_kapi.c
@@ -490,6 +490,7 @@ int netlbl_skbuff_getattr(const struct sk_buff *skb,
  * netlbl_skbuff_err - Handle a LSM error on a sk_buff
  * @skb: the packet
  * @error: the error code
+ * @gateway: true if host is acting as a gateway, false otherwise
  *
  * Description:
  * Deal with a LSM problem when handling the packet in @skb, typically this is
@@ -497,10 +498,10 @@ int netlbl_skbuff_getattr(const struct sk_buff *skb,
  * according to the packet's labeling protocol.
  *
  */
-void netlbl_skbuff_err(struct sk_buff *skb, int error)
+void netlbl_skbuff_err(struct sk_buff *skb, int error, int gateway)
 {
         if (CIPSO_V4_OPTEXIST(skb))
-                cipso_v4_error(skb, error, 0);
+                cipso_v4_error(skb, error, gateway);
 }
 
 /**
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index b520667a24be..a91146a6b37d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -4101,6 +4101,8 @@ static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
                         return err;
                 err = avc_has_perm(sk_sid, peer_sid,
                                    SECCLASS_PEER, PEER__RECV, &ad);
+                if (err)
+                        selinux_netlbl_err(skb, err, 0);
         } else {
                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
                 if (err)
@@ -4156,10 +4158,14 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
                         return err;
                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
                                                peer_sid, &ad);
-                if (err)
+                if (err) {
+                        selinux_netlbl_err(skb, err, 0);
                         return err;
+                }
                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
                                    PEER__RECV, &ad);
+                if (err)
+                        selinux_netlbl_err(skb, err, 0);
         }
 
         if (secmark_active) {
@@ -4396,6 +4402,7 @@ out:
 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
                                        u16 family)
 {
+        int err;
         char *addrp;
         u32 peer_sid;
         struct avc_audit_data ad;
@@ -4419,10 +4426,14 @@ static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
                 return NF_DROP;
 
-        if (peerlbl_active)
-                if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
-                                             peer_sid, &ad) != 0)
+        if (peerlbl_active) {
+                err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
+                                               peer_sid, &ad);
+                if (err) {
+                        selinux_netlbl_err(skb, err, 1);
                         return NF_DROP;
+                }
+        }
 
         if (secmark_active)
                 if (avc_has_perm(peer_sid, skb->secmark,
diff --git a/security/selinux/include/netlabel.h b/security/selinux/include/netlabel.h
index 487a7d81fe20..d4e3ac8a7fbf 100644
--- a/security/selinux/include/netlabel.h
+++ b/security/selinux/include/netlabel.h
@@ -39,6 +39,8 @@
 #ifdef CONFIG_NETLABEL
 void selinux_netlbl_cache_invalidate(void);
 
+void selinux_netlbl_err(struct sk_buff *skb, int error, int gateway);
+
 void selinux_netlbl_sk_security_reset(struct sk_security_struct *ssec,
                                       int family);
 
@@ -63,6 +65,13 @@ static inline void selinux_netlbl_cache_invalidate(void)
         return;
 }
 
+static inline void selinux_netlbl_err(struct sk_buff *skb,
+                                      int error,
+                                      int gateway)
+{
+        return;
+}
+
 static inline void selinux_netlbl_sk_security_reset(
                                                struct sk_security_struct *ssec,
                                                int family)
diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c
index b9ce5fcf3432..4053f7fc95fb 100644
--- a/security/selinux/netlabel.c
+++ b/security/selinux/netlabel.c
@@ -108,6 +108,24 @@ void selinux_netlbl_cache_invalidate(void)
 }
 
 /**
+ * selinux_netlbl_err - Handle a NetLabel packet error
+ * @skb: the packet
+ * @error: the error code
+ * @gateway: true if host is acting as a gateway, false otherwise
+ *
+ * Description:
+ * When a packet is dropped due to a call to avc_has_perm() pass the error
+ * code to the NetLabel subsystem so any protocol specific processing can be
+ * done.  This is safe to call even if you are unsure if NetLabel labeling is
+ * present on the packet, NetLabel is smart enough to only act when it should.
+ *
+ */
+void selinux_netlbl_err(struct sk_buff *skb, int error, int gateway)
+{
+        netlbl_skbuff_err(skb, error, gateway);
+}
+
+/**
  * selinux_netlbl_sk_security_reset - Reset the NetLabel fields
  * @ssec: the sk_security_struct
  * @family: the socket family
@@ -289,7 +307,7 @@ int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec,
                 return 0;
 
         if (nlbl_sid != SECINITSID_UNLABELED)
-                netlbl_skbuff_err(skb, rc);
+                netlbl_skbuff_err(skb, rc, 0);
         return rc;
 }