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

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>

drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c

@@ -1148,7 +1148,7 @@ static struct sock *chtls_recv_sock(struct sock *lsk,
 		fl6.daddr = ip6h->saddr;
 		fl6.fl6_dport = inet_rsk(oreq)->ir_rmt_port;
 		fl6.fl6_sport = htons(inet_rsk(oreq)->ir_num);
-		security_req_classify_flow(oreq, flowi6_to_flowi(&fl6));
+		security_req_classify_flow(oreq, flowi6_to_flowi_common(&fl6));
 		dst = ip6_dst_lookup_flow(sock_net(lsk), lsk, &fl6, NULL);
 		if (IS_ERR(dst))
 			goto free_sk;

drivers/net/wireguard/socket.c

@@ -49,7 +49,7 @@ static int send4(struct wg_device *wg, struct sk_buff *skb,
 		rt = dst_cache_get_ip4(cache, &fl.saddr);
 
 	if (!rt) {
-		security_sk_classify_flow(sock, flowi4_to_flowi(&fl));
+		security_sk_classify_flow(sock, flowi4_to_flowi_common(&fl));
 		if (unlikely(!inet_confirm_addr(sock_net(sock), NULL, 0,
 						fl.saddr, RT_SCOPE_HOST))) {
 			endpoint->src4.s_addr = 0;
@@ -129,7 +129,7 @@ static int send6(struct wg_device *wg, struct sk_buff *skb,
 		dst = dst_cache_get_ip6(cache, &fl.saddr);
 
 	if (!dst) {
-		security_sk_classify_flow(sock, flowi6_to_flowi(&fl));
+		security_sk_classify_flow(sock, flowi6_to_flowi_common(&fl));
 		if (unlikely(!ipv6_addr_any(&fl.saddr) &&
 			     !ipv6_chk_addr(sock_net(sock), &fl.saddr, NULL, 0))) {
 			endpoint->src6 = fl.saddr = in6addr_any;

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 */

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.

include/linux/security.h

@@ -167,7 +167,7 @@ struct sk_buff;
 struct sock;
 struct sockaddr;
 struct socket;
-struct flowi;
+struct flowi_common;
 struct dst_entry;
 struct xfrm_selector;
 struct xfrm_policy;
@@ -1355,8 +1355,9 @@ 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);
@@ -1507,11 +1508,13 @@ 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)
 {
 }
 
@@ -1638,9 +1641,9 @@ 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 */
 
@@ -1692,7 +1695,8 @@ 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;
 }
@@ -1702,7 +1706,8 @@ 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)
 {
 }
 

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);

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;

net/dccp/ipv4.c

@@ -464,7 +464,7 @@ static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk,
 		.fl4_dport = dccp_hdr(skb)->dccph_sport,
 	};
 
-	security_skb_classify_flow(skb, flowi4_to_flowi(&fl4));
+	security_skb_classify_flow(skb, flowi4_to_flowi_common(&fl4));
 	rt = ip_route_output_flow(net, &fl4, sk);
 	if (IS_ERR(rt)) {
 		IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);

net/dccp/ipv6.c

@@ -203,7 +203,7 @@ static int dccp_v6_send_response(const struct sock *sk, struct request_sock *req
 	fl6.flowi6_oif = ireq->ir_iif;
 	fl6.fl6_dport = ireq->ir_rmt_port;
 	fl6.fl6_sport = htons(ireq->ir_num);
-	security_req_classify_flow(req, flowi6_to_flowi(&fl6));
+	security_req_classify_flow(req, flowi6_to_flowi_common(&fl6));
 
 
 	rcu_read_lock();
@@ -279,7 +279,7 @@ static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
 	fl6.flowi6_oif = inet6_iif(rxskb);
 	fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
 	fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
-	security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
+	security_skb_classify_flow(rxskb, flowi6_to_flowi_common(&fl6));
 
 	/* sk = NULL, but it is safe for now. RST socket required. */
 	dst = ip6_dst_lookup_flow(sock_net(ctl_sk), ctl_sk, &fl6, NULL);
@@ -907,7 +907,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	fl6.flowi6_oif = sk->sk_bound_dev_if;
 	fl6.fl6_dport = usin->sin6_port;
 	fl6.fl6_sport = inet->inet_sport;
-	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
 
 	opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 	final_p = fl6_update_dst(&fl6, opt, &final);

net/ipv4/icmp.c

@@ -447,7 +447,7 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
 	fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
 	fl4.flowi4_proto = IPPROTO_ICMP;
 	fl4.flowi4_oif = l3mdev_master_ifindex(skb->dev);
-	security_skb_classify_flow(skb, flowi4_to_flowi(&fl4));
+	security_skb_classify_flow(skb, flowi4_to_flowi_common(&fl4));
 	rt = ip_route_output_key(net, &fl4);
 	if (IS_ERR(rt))
 		goto out_unlock;
@@ -503,7 +503,7 @@ static struct rtable *icmp_route_lookup(struct net *net,
 	route_lookup_dev = icmp_get_route_lookup_dev(skb_in);
 	fl4->flowi4_oif = l3mdev_master_ifindex(route_lookup_dev);
 
-	security_skb_classify_flow(skb_in, flowi4_to_flowi(fl4));
+	security_skb_classify_flow(skb_in, flowi4_to_flowi_common(fl4));
 	rt = ip_route_output_key_hash(net, fl4, skb_in);
 	if (IS_ERR(rt))
 		return rt;

net/ipv4/inet_connection_sock.c

@@ -602,7 +602,7 @@ struct dst_entry *inet_csk_route_req(const struct sock *sk,
 			   (opt && opt->opt.srr) ? opt->opt.faddr : ireq->ir_rmt_addr,
 			   ireq->ir_loc_addr, ireq->ir_rmt_port,
 			   htons(ireq->ir_num), sk->sk_uid);
-	security_req_classify_flow(req, flowi4_to_flowi(fl4));
+	security_req_classify_flow(req, flowi4_to_flowi_common(fl4));
 	rt = ip_route_output_flow(net, fl4, sk);
 	if (IS_ERR(rt))
 		goto no_route;
@@ -640,7 +640,7 @@ struct dst_entry *inet_csk_route_child_sock(const struct sock *sk,
 			   (opt && opt->opt.srr) ? opt->opt.faddr : ireq->ir_rmt_addr,
 			   ireq->ir_loc_addr, ireq->ir_rmt_port,
 			   htons(ireq->ir_num), sk->sk_uid);
-	security_req_classify_flow(req, flowi4_to_flowi(fl4));
+	security_req_classify_flow(req, flowi4_to_flowi_common(fl4));
 	rt = ip_route_output_flow(net, fl4, sk);
 	if (IS_ERR(rt))
 		goto no_route;

net/ipv4/ip_output.c

@@ -1700,7 +1700,7 @@ void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
 			   daddr, saddr,
 			   tcp_hdr(skb)->source, tcp_hdr(skb)->dest,
 			   arg->uid);
-	security_skb_classify_flow(skb, flowi4_to_flowi(&fl4));
+	security_skb_classify_flow(skb, flowi4_to_flowi_common(&fl4));
 	rt = ip_route_output_key(net, &fl4);
 	if (IS_ERR(rt))
 		return;

net/ipv4/ping.c

@@ -778,7 +778,7 @@ static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	fl4.fl4_icmp_type = user_icmph.type;
 	fl4.fl4_icmp_code = user_icmph.code;
 
-	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
+	security_sk_classify_flow(sk, flowi4_to_flowi_common(&fl4));
 	rt = ip_route_output_flow(net, &fl4, sk);
 	if (IS_ERR(rt)) {
 		err = PTR_ERR(rt);

net/ipv4/raw.c

@@ -640,7 +640,7 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 			goto done;
 	}
 
-	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
+	security_sk_classify_flow(sk, flowi4_to_flowi_common(&fl4));
 	rt = ip_route_output_flow(net, &fl4, sk);
 	if (IS_ERR(rt)) {
 		err = PTR_ERR(rt);

net/ipv4/syncookies.c

@@ -418,7 +418,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
 			   inet_sk_flowi_flags(sk),
 			   opt->srr ? opt->faddr : ireq->ir_rmt_addr,
 			   ireq->ir_loc_addr, th->source, th->dest, sk->sk_uid);
-	security_req_classify_flow(req, flowi4_to_flowi(&fl4));
+	security_req_classify_flow(req, flowi4_to_flowi_common(&fl4));
 	rt = ip_route_output_key(sock_net(sk), &fl4);
 	if (IS_ERR(rt)) {
 		reqsk_free(req);

net/ipv4/udp.c

@@ -1197,7 +1197,7 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 				   faddr, saddr, dport, inet->inet_sport,
 				   sk->sk_uid);
 
-		security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
+		security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
 		rt = ip_route_output_flow(net, fl4, sk);
 		if (IS_ERR(rt)) {
 			err = PTR_ERR(rt);

net/ipv6/af_inet6.c

@@ -819,7 +819,7 @@ int inet6_sk_rebuild_header(struct sock *sk)
 		fl6.fl6_dport = inet->inet_dport;
 		fl6.fl6_sport = inet->inet_sport;
 		fl6.flowi6_uid = sk->sk_uid;
-		security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+		security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
 
 		rcu_read_lock();
 		final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),

net/ipv6/datagram.c

@@ -60,7 +60,7 @@ static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
 	if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
 		fl6->flowi6_oif = np->mcast_oif;
 
-	security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
+	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
 }
 
 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)

net/ipv6/icmp.c

@@ -567,7 +567,7 @@ void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info,
 	fl6.fl6_icmp_code = code;
 	fl6.flowi6_uid = sock_net_uid(net, NULL);
 	fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, NULL);
-	security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
+	security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
 
 	np = inet6_sk(sk);
 
@@ -749,7 +749,7 @@ static void icmpv6_echo_reply(struct sk_buff *skb)
 	fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
 	fl6.flowi6_mark = mark;
 	fl6.flowi6_uid = sock_net_uid(net, NULL);
-	security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
+	security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
 
 	local_bh_disable();
 	sk = icmpv6_xmit_lock(net);
@@ -1002,7 +1002,7 @@ void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
 	fl6->fl6_icmp_type	= type;
 	fl6->fl6_icmp_code	= 0;
 	fl6->flowi6_oif		= oif;
-	security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
+	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
 }
 
 static void __net_exit icmpv6_sk_exit(struct net *net)

net/ipv6/inet6_connection_sock.c

@@ -46,7 +46,7 @@ struct dst_entry *inet6_csk_route_req(const struct sock *sk,
 	fl6->fl6_dport = ireq->ir_rmt_port;
 	fl6->fl6_sport = htons(ireq->ir_num);
 	fl6->flowi6_uid = sk->sk_uid;
-	security_req_classify_flow(req, flowi6_to_flowi(fl6));
+	security_req_classify_flow(req, flowi6_to_flowi_common(fl6));
 
 	dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 	if (IS_ERR(dst))
@@ -95,7 +95,7 @@ static struct dst_entry *inet6_csk_route_socket(struct sock *sk,
 	fl6->fl6_sport = inet->inet_sport;
 	fl6->fl6_dport = inet->inet_dport;
 	fl6->flowi6_uid = sk->sk_uid;
-	security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
+	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
 
 	rcu_read_lock();
 	final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);

net/ipv6/netfilter/nf_reject_ipv6.c

@@ -179,7 +179,7 @@ void nf_send_reset6(struct net *net, struct sk_buff *oldskb, int hook)
 
 	fl6.flowi6_oif = l3mdev_master_ifindex(skb_dst(oldskb)->dev);
 	fl6.flowi6_mark = IP6_REPLY_MARK(net, oldskb->mark);
-	security_skb_classify_flow(oldskb, flowi6_to_flowi(&fl6));
+	security_skb_classify_flow(oldskb, flowi6_to_flowi_common(&fl6));
 	dst = ip6_route_output(net, NULL, &fl6);
 	if (dst->error) {
 		dst_release(dst);

net/ipv6/ping.c

@@ -111,7 +111,7 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	fl6.flowi6_uid = sk->sk_uid;
 	fl6.fl6_icmp_type = user_icmph.icmp6_type;
 	fl6.fl6_icmp_code = user_icmph.icmp6_code;
-	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
 
 	ipcm6_init_sk(&ipc6, np);
 	ipc6.sockc.mark = sk->sk_mark;

net/ipv6/raw.c

@@ -915,7 +915,7 @@ static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 		fl6.flowi6_oif = np->mcast_oif;
 	else if (!fl6.flowi6_oif)
 		fl6.flowi6_oif = np->ucast_oif;
-	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
 
 	if (hdrincl)
 		fl6.flowi6_flags |= FLOWI_FLAG_KNOWN_NH;

net/ipv6/syncookies.c

@@ -233,7 +233,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 		fl6.fl6_dport = ireq->ir_rmt_port;
 		fl6.fl6_sport = inet_sk(sk)->inet_sport;
 		fl6.flowi6_uid = sk->sk_uid;
-		security_req_classify_flow(req, flowi6_to_flowi(&fl6));
+		security_req_classify_flow(req, flowi6_to_flowi_common(&fl6));
 
 		dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 		if (IS_ERR(dst))