lsm,selinux: pass flowi_common instead of flowi to the LSM hooks

[ Upstream commit 3df98d79215ace13d1e91ddfc5a67a0f5acbd83f ]

As pointed out by Herbert in a recent related patch, the LSM hooks do
not have the necessary address family information to use the flowi
struct safely.  As none of the LSMs currently use any of the protocol
specific flowi information, replace the flowi pointers with pointers
to the address family independent flowi_common struct.

Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

5 files changed, 30 insertions, 15 deletions

diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index a6a3d4ddfc2d..d13631a5e908 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h
@@ -311,7 +311,7 @@ LSM_HOOK(int, 0, secmark_relabel_packet, u32 secid)
 LSM_HOOK(void, LSM_RET_VOID, secmark_refcount_inc, void)
 LSM_HOOK(void, LSM_RET_VOID, secmark_refcount_dec, void)
 LSM_HOOK(void, LSM_RET_VOID, req_classify_flow, const struct request_sock *req,
-	 struct flowi *fl)
+	 struct flowi_common *flic)
 LSM_HOOK(int, 0, tun_dev_alloc_security, void **security)
 LSM_HOOK(void, LSM_RET_VOID, tun_dev_free_security, void *security)
 LSM_HOOK(int, 0, tun_dev_create, void)
@@ -351,7 +351,7 @@ LSM_HOOK(int, 0, xfrm_state_delete_security, struct xfrm_state *x)
 LSM_HOOK(int, 0, xfrm_policy_lookup, struct xfrm_sec_ctx *ctx, u32 fl_secid,
 	 u8 dir)
 LSM_HOOK(int, 1, xfrm_state_pol_flow_match, struct xfrm_state *x,
-	 struct xfrm_policy *xp, const struct flowi *fl)
+	 struct xfrm_policy *xp, const struct flowi_common *flic)
 LSM_HOOK(int, 0, xfrm_decode_session, struct sk_buff *skb, u32 *secid,
 	 int ckall)
 #endif /* CONFIG_SECURITY_NETWORK_XFRM */
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index a8531b37e6f5..64cdf4d7bfb3 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -1105,7 +1105,7 @@
  * @xfrm_state_pol_flow_match:
  *	@x contains the state to match.
  *	@xp contains the policy to check for a match.
- *	@fl contains the flow to check for a match.
+ *	@flic contains the flowi_common struct to check for a match.
  *	Return 1 if there is a match.
  * @xfrm_decode_session:
  *	@skb points to skb to decode.
diff --git a/include/linux/security.h b/include/linux/security.h
index 330029ef7e89..e9b4b5410614 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -170,7 +170,7 @@ struct sk_buff;
 struct sock;
 struct sockaddr;
 struct socket;
-struct flowi;
+struct flowi_common;
 struct dst_entry;
 struct xfrm_selector;
 struct xfrm_policy;
@@ -1363,8 +1363,9 @@ int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u
 int security_sk_alloc(struct sock *sk, int family, gfp_t priority);
 void security_sk_free(struct sock *sk);
 void security_sk_clone(const struct sock *sk, struct sock *newsk);
-void security_sk_classify_flow(struct sock *sk, struct flowi *fl);
-void security_req_classify_flow(const struct request_sock *req, struct flowi *fl);
+void security_sk_classify_flow(struct sock *sk, struct flowi_common *flic);
+void security_req_classify_flow(const struct request_sock *req,
+				struct flowi_common *flic);
 void security_sock_graft(struct sock*sk, struct socket *parent);
 int security_inet_conn_request(struct sock *sk,
 			struct sk_buff *skb, struct request_sock *req);
@@ -1515,11 +1516,13 @@ static inline void security_sk_clone(const struct sock *sk, struct sock *newsk)
 {
 }
 
-static inline void security_sk_classify_flow(struct sock *sk, struct flowi *fl)
+static inline void security_sk_classify_flow(struct sock *sk,
+					     struct flowi_common *flic)
 {
 }
 
-static inline void security_req_classify_flow(const struct request_sock *req, struct flowi *fl)
+static inline void security_req_classify_flow(const struct request_sock *req,
+					      struct flowi_common *flic)
 {
 }
 
@@ -1646,9 +1649,9 @@ void security_xfrm_state_free(struct xfrm_state *x);
 int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir);
 int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
 				       struct xfrm_policy *xp,
-				       const struct flowi *fl);
+				       const struct flowi_common *flic);
 int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid);
-void security_skb_classify_flow(struct sk_buff *skb, struct flowi *fl);
+void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic);
 
 #else	/* CONFIG_SECURITY_NETWORK_XFRM */
 
@@ -1700,7 +1703,8 @@ static inline int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_s
 }
 
 static inline int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
-			struct xfrm_policy *xp, const struct flowi *fl)
+						     struct xfrm_policy *xp,
+						     const struct flowi_common *flic)
 {
 	return 1;
 }
@@ -1710,7 +1714,8 @@ static inline int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
 	return 0;
 }
 
-static inline void security_skb_classify_flow(struct sk_buff *skb, struct flowi *fl)
+static inline void security_skb_classify_flow(struct sk_buff *skb,
+					      struct flowi_common *flic)
 {
 }
 
diff --git a/include/net/flow.h b/include/net/flow.h
index b2531df3f65f..39d0cedcddee 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -195,11 +195,21 @@ static inline struct flowi *flowi4_to_flowi(struct flowi4 *fl4)
 	return container_of(fl4, struct flowi, u.ip4);
 }
 
+static inline struct flowi_common *flowi4_to_flowi_common(struct flowi4 *fl4)
+{
+	return &(flowi4_to_flowi(fl4)->u.__fl_common);
+}
+
 static inline struct flowi *flowi6_to_flowi(struct flowi6 *fl6)
 {
 	return container_of(fl6, struct flowi, u.ip6);
 }
 
+static inline struct flowi_common *flowi6_to_flowi_common(struct flowi6 *fl6)
+{
+	return &(flowi6_to_flowi(fl6)->u.__fl_common);
+}
+
 static inline struct flowi *flowidn_to_flowi(struct flowidn *fldn)
 {
 	return container_of(fldn, struct flowi, u.dn);
diff --git a/include/net/route.h b/include/net/route.h
index a07c277cd33e..2551f3f03b37 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -165,7 +165,7 @@ static inline struct rtable *ip_route_output_ports(struct net *net, struct flowi
 			   sk ? inet_sk_flowi_flags(sk) : 0,
 			   daddr, saddr, dport, sport, sock_net_uid(net, sk));
 	if (sk)
-		security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
+		security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
 	return ip_route_output_flow(net, fl4, sk);
 }
 
@@ -322,7 +322,7 @@ static inline struct rtable *ip_route_connect(struct flowi4 *fl4,
 		ip_rt_put(rt);
 		flowi4_update_output(fl4, oif, tos, fl4->daddr, fl4->saddr);
 	}
-	security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
+	security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
 	return ip_route_output_flow(net, fl4, sk);
 }
 
@@ -338,7 +338,7 @@ static inline struct rtable *ip_route_newports(struct flowi4 *fl4, struct rtable
 		flowi4_update_output(fl4, sk->sk_bound_dev_if,
 				     RT_CONN_FLAGS(sk), fl4->daddr,
 				     fl4->saddr);
-		security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
+		security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
 		return ip_route_output_flow(sock_net(sk), fl4, sk);
 	}
 	return rt;