Commit c3df39ac authored by Dongseok Yi's avatar Dongseok Yi Committed by Jakub Kicinski
Browse files

udp: ipv4: manipulate network header of NATed UDP GRO fraglist 



UDP/IP header of UDP GROed frag_skbs are not updated even after NAT
forwarding. Only the header of head_skb from ip_finish_output_gso ->
skb_gso_segment is updated but following frag_skbs are not updated.

A call path skb_mac_gso_segment -> inet_gso_segment ->
udp4_ufo_fragment -> __udp_gso_segment -> __udp_gso_segment_list
does not try to update UDP/IP header of the segment list but copy
only the MAC header.

Update port, addr and check of each skb of the segment list in
__udp_gso_segment_list. It covers both SNAT and DNAT.

Fixes: 9fd1ff5d (udp: Support UDP fraglist GRO/GSO.)
Signed-off-by: default avatarDongseok Yi <dseok.yi@samsung.com>
Acked-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
Link: https://lore.kernel.org/r/1611962007-80092-1-git-send-email-dseok.yi@samsung.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 28e104d0

include/net/udp.h

+1 −1
Original line number Diff line number Diff line
@@ -178,7 +178,7 @@ struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb, 
int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);



struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,

				  netdev_features_t features);

				  netdev_features_t features, bool is_ipv6);



static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)

{

net/ipv4/udp_offload.c

+64 −5
Original line number Diff line number Diff line
@@ -187,8 +187,67 @@ struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb, 
}

EXPORT_SYMBOL(skb_udp_tunnel_segment);



static void __udpv4_gso_segment_csum(struct sk_buff *seg,

				     __be32 *oldip, __be32 *newip,

				     __be16 *oldport, __be16 *newport)

{

	struct udphdr *uh;

	struct iphdr *iph;



	if (*oldip == *newip && *oldport == *newport)

		return;



	uh = udp_hdr(seg);

	iph = ip_hdr(seg);



	if (uh->check) {

		inet_proto_csum_replace4(&uh->check, seg, *oldip, *newip,

					 true);

		inet_proto_csum_replace2(&uh->check, seg, *oldport, *newport,

					 false);

		if (!uh->check)

			uh->check = CSUM_MANGLED_0;

	}

	*oldport = *newport;



	csum_replace4(&iph->check, *oldip, *newip);

	*oldip = *newip;

}



static struct sk_buff *__udpv4_gso_segment_list_csum(struct sk_buff *segs)

{

	struct sk_buff *seg;

	struct udphdr *uh, *uh2;

	struct iphdr *iph, *iph2;



	seg = segs;

	uh = udp_hdr(seg);

	iph = ip_hdr(seg);



	if ((udp_hdr(seg)->dest == udp_hdr(seg->next)->dest) &&

	    (udp_hdr(seg)->source == udp_hdr(seg->next)->source) &&

	    (ip_hdr(seg)->daddr == ip_hdr(seg->next)->daddr) &&

	    (ip_hdr(seg)->saddr == ip_hdr(seg->next)->saddr))

		return segs;



	while ((seg = seg->next)) {

		uh2 = udp_hdr(seg);

		iph2 = ip_hdr(seg);



		__udpv4_gso_segment_csum(seg,

					 &iph2->saddr, &iph->saddr,

					 &uh2->source, &uh->source);

		__udpv4_gso_segment_csum(seg,

					 &iph2->daddr, &iph->daddr,

					 &uh2->dest, &uh->dest);

	}



	return segs;

}



static struct sk_buff *__udp_gso_segment_list(struct sk_buff *skb,

					      netdev_features_t features)

					      netdev_features_t features,

					      bool is_ipv6)

{

	unsigned int mss = skb_shinfo(skb)->gso_size;
@@ -198,11 +257,11 @@ static struct sk_buff *__udp_gso_segment_list(struct sk_buff *skb, 


	udp_hdr(skb)->len = htons(sizeof(struct udphdr) + mss);



	return skb;

	return is_ipv6 ? skb : __udpv4_gso_segment_list_csum(skb);

}



struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,

				  netdev_features_t features)

				  netdev_features_t features, bool is_ipv6)

{

	struct sock *sk = gso_skb->sk;

	unsigned int sum_truesize = 0;
@@ -214,7 +273,7 @@ struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb, 
	__be16 newlen;



	if (skb_shinfo(gso_skb)->gso_type & SKB_GSO_FRAGLIST)

		return __udp_gso_segment_list(gso_skb, features);

		return __udp_gso_segment_list(gso_skb, features, is_ipv6);



	mss = skb_shinfo(gso_skb)->gso_size;

	if (gso_skb->len <= sizeof(*uh) + mss)
@@ -328,7 +387,7 @@ static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, 
		goto out;



	if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4)

		return __udp_gso_segment(skb, features);

		return __udp_gso_segment(skb, features, false);



	mss = skb_shinfo(skb)->gso_size;

	if (unlikely(skb->len <= mss))

net/ipv6/udp_offload.c

+1 −1
Original line number Diff line number Diff line
@@ -42,7 +42,7 @@ static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, 
			goto out;



		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4)

			return __udp_gso_segment(skb, features);

			return __udp_gso_segment(skb, features, true);



		mss = skb_shinfo(skb)->gso_size;

		if (unlikely(skb->len <= mss))