Commit 9bfce73c authored by Vadim Fedorenko's avatar Vadim Fedorenko Committed by David S. Miller
Browse files

udp: check encap socket in __udp_lib_err 



Commit d26796ae ("udp: check udp sock encap_type in __udp_lib_err")
added checks for encapsulated sockets but it broke cases when there is
no implementation of encap_err_lookup for encapsulation, i.e. ESP in
UDP encapsulation. Fix it by calling encap_err_lookup only if socket
implements this method otherwise treat it as legal socket.

Fixes: d26796ae ("udp: check udp sock encap_type in __udp_lib_err")
Signed-off-by: default avatarVadim Fedorenko <vfedorenko@novek.ru>
Reviewed-by: default avatarXin Long <lucien.xin@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 58acd100

net/ipv4/udp.c

+19 −6
Original line number Diff line number Diff line
@@ -645,10 +645,12 @@ static struct sock *__udp4_lib_err_encap(struct net *net, 
					 const struct iphdr *iph,

					 struct udphdr *uh,

					 struct udp_table *udptable,

					 struct sock *sk,

					 struct sk_buff *skb, u32 info)

{

	int (*lookup)(struct sock *sk, struct sk_buff *skb);

	int network_offset, transport_offset;

	struct sock *sk;

	struct udp_sock *up;



	network_offset = skb_network_offset(skb);

	transport_offset = skb_transport_offset(skb);
@@ -659,18 +661,28 @@ static struct sock *__udp4_lib_err_encap(struct net *net, 
	/* Transport header needs to point to the UDP header */

	skb_set_transport_header(skb, iph->ihl << 2);



	if (sk) {

		up = udp_sk(sk);



		lookup = READ_ONCE(up->encap_err_lookup);

		if (lookup && lookup(sk, skb))

			sk = NULL;



		goto out;

	}



	sk = __udp4_lib_lookup(net, iph->daddr, uh->source,

			       iph->saddr, uh->dest, skb->dev->ifindex, 0,

			       udptable, NULL);

	if (sk) {

		int (*lookup)(struct sock *sk, struct sk_buff *skb);

		struct udp_sock *up = udp_sk(sk);

		up = udp_sk(sk);



		lookup = READ_ONCE(up->encap_err_lookup);

		if (!lookup || lookup(sk, skb))

			sk = NULL;

	}



out:

	if (!sk)

		sk = ERR_PTR(__udp4_lib_err_encap_no_sk(skb, info));
@@ -707,15 +719,16 @@ int __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable) 
	sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,

			       iph->saddr, uh->source, skb->dev->ifindex,

			       inet_sdif(skb), udptable, NULL);



	if (!sk || udp_sk(sk)->encap_type) {

		/* No socket for error: try tunnels before discarding */

		sk = ERR_PTR(-ENOENT);

		if (static_branch_unlikely(&udp_encap_needed_key)) {

			sk = __udp4_lib_err_encap(net, iph, uh, udptable, skb,

			sk = __udp4_lib_err_encap(net, iph, uh, udptable, sk, skb,

						  info);

			if (!sk)

				return 0;

		}

		} else

			sk = ERR_PTR(-ENOENT);



		if (IS_ERR(sk)) {

			__ICMP_INC_STATS(net, ICMP_MIB_INERRORS);

net/ipv6/udp.c

+19 −6
Original line number Diff line number Diff line
@@ -502,12 +502,14 @@ static struct sock *__udp6_lib_err_encap(struct net *net, 
					 const struct ipv6hdr *hdr, int offset,

					 struct udphdr *uh,

					 struct udp_table *udptable,

					 struct sock *sk,

					 struct sk_buff *skb,

					 struct inet6_skb_parm *opt,

					 u8 type, u8 code, __be32 info)

{

	int (*lookup)(struct sock *sk, struct sk_buff *skb);

	int network_offset, transport_offset;

	struct sock *sk;

	struct udp_sock *up;



	network_offset = skb_network_offset(skb);

	transport_offset = skb_transport_offset(skb);
@@ -518,18 +520,28 @@ static struct sock *__udp6_lib_err_encap(struct net *net, 
	/* Transport header needs to point to the UDP header */

	skb_set_transport_header(skb, offset);



	if (sk) {

		up = udp_sk(sk);



		lookup = READ_ONCE(up->encap_err_lookup);

		if (lookup && lookup(sk, skb))

			sk = NULL;



		goto out;

	}



	sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source,

			       &hdr->saddr, uh->dest,

			       inet6_iif(skb), 0, udptable, skb);

	if (sk) {

		int (*lookup)(struct sock *sk, struct sk_buff *skb);

		struct udp_sock *up = udp_sk(sk);

		up = udp_sk(sk);



		lookup = READ_ONCE(up->encap_err_lookup);

		if (!lookup || lookup(sk, skb))

			sk = NULL;

	}



out:

	if (!sk) {

		sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code,

							offset, info));
@@ -558,16 +570,17 @@ int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 


	sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,

			       inet6_iif(skb), inet6_sdif(skb), udptable, NULL);



	if (!sk || udp_sk(sk)->encap_type) {

		/* No socket for error: try tunnels before discarding */

		sk = ERR_PTR(-ENOENT);

		if (static_branch_unlikely(&udpv6_encap_needed_key)) {

			sk = __udp6_lib_err_encap(net, hdr, offset, uh,

						  udptable, skb,

						  udptable, sk, skb,

						  opt, type, code, info);

			if (!sk)

				return 0;

		}

		} else

			sk = ERR_PTR(-ENOENT);



		if (IS_ERR(sk)) {

			__ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),