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![Daniel Borkmann](/assets/img/avatar_default.png)
We noticed a GRO issue for UDP-based encaps such as vxlan/geneve when the csum for the UDP header itself is 0. In that case, GRO aggregation does not take place on the phys dev, but instead is deferred to the vxlan/geneve driver (see trace below). The reason is essentially that GRO aggregation bails out in udp_gro_receive() for such case when drivers marked the skb with CHECKSUM_UNNECESSARY (ice, i40e, others) where for non-zero csums2abb7cdc0d
("udp: Add support for doing checksum unnecessary conversion") promotes those skbs to CHECKSUM_COMPLETE and napi context has csum_valid set. This is however not the case for zero UDP csum (here: csum_cnt is still 0 and csum_valid continues to be false). At the same time57c67ff4bd
("udp: additional GRO support") added matches on !uh->check ^ !uh2->check as part to determine candidates for aggregation, so it certainly is expected to handle zero csums in udp_gro_receive(). The purpose of the check added via662880f442
("net: Allow GRO to use and set levels of checksum unnecessary") seems to catch bad csum and stop aggregation right away. One way to fix aggregation in the zero case is to only perform the !csum_valid check in udp_gro_receive() if uh->check is infact non-zero. Before: [...] swapper 0 [008] 731.946506: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100400 len=1500 (1) swapper 0 [008] 731.946507: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100200 len=1500 swapper 0 [008] 731.946507: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101100 len=1500 swapper 0 [008] 731.946508: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101700 len=1500 swapper 0 [008] 731.946508: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101b00 len=1500 swapper 0 [008] 731.946508: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100600 len=1500 swapper 0 [008] 731.946508: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100f00 len=1500 swapper 0 [008] 731.946509: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100a00 len=1500 swapper 0 [008] 731.946516: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100500 len=1500 swapper 0 [008] 731.946516: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100700 len=1500 swapper 0 [008] 731.946516: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101d00 len=1500 (2) swapper 0 [008] 731.946517: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101000 len=1500 swapper 0 [008] 731.946517: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101c00 len=1500 swapper 0 [008] 731.946517: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101400 len=1500 swapper 0 [008] 731.946518: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100e00 len=1500 swapper 0 [008] 731.946518: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497101600 len=1500 swapper 0 [008] 731.946521: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff966497100800 len=774 swapper 0 [008] 731.946530: net:netif_receive_skb: dev=test_vxlan skbaddr=0xffff966497100400 len=14032 (1) swapper 0 [008] 731.946530: net:netif_receive_skb: dev=test_vxlan skbaddr=0xffff966497101d00 len=9112 (2) [...] # netperf -H 10.55.10.4 -t TCP_STREAM -l 20 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.55.10.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 20.01 13129.24 After: [...] swapper 0 [026] 521.862641: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff93ab0d479000 len=11286 (1) swapper 0 [026] 521.862643: net:netif_receive_skb: dev=test_vxlan skbaddr=0xffff93ab0d479000 len=11236 (1) swapper 0 [026] 521.862650: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff93ab0d478500 len=2898 (2) swapper 0 [026] 521.862650: net:netif_receive_skb: dev=enp10s0f0 skbaddr=0xffff93ab0d479f00 len=8490 (3) swapper 0 [026] 521.862653: net:netif_receive_skb: dev=test_vxlan skbaddr=0xffff93ab0d478500 len=2848 (2) swapper 0 [026] 521.862653: net:netif_receive_skb: dev=test_vxlan skbaddr=0xffff93ab0d479f00 len=8440 (3) [...] # netperf -H 10.55.10.4 -t TCP_STREAM -l 20 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.55.10.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 20.01 24576.53 Fixes:57c67ff4bd
("udp: additional GRO support") Fixes:662880f442
("net: Allow GRO to use and set levels of checksum unnecessary") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jesse Brandeburg <jesse.brandeburg@intel.com> Cc: Tom Herbert <tom@herbertland.com> Acked-by: Willem de Bruijn <willemb@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/r/20210226212248.8300-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
700 lines
18 KiB
C
700 lines
18 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* IPV4 GSO/GRO offload support
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* Linux INET implementation
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*
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* UDPv4 GSO support
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*/
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#include <linux/skbuff.h>
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#include <net/udp.h>
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#include <net/protocol.h>
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#include <net/inet_common.h>
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static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
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netdev_features_t features,
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struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb,
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netdev_features_t features),
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__be16 new_protocol, bool is_ipv6)
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{
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int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb);
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bool remcsum, need_csum, offload_csum, gso_partial;
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struct sk_buff *segs = ERR_PTR(-EINVAL);
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struct udphdr *uh = udp_hdr(skb);
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u16 mac_offset = skb->mac_header;
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__be16 protocol = skb->protocol;
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u16 mac_len = skb->mac_len;
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int udp_offset, outer_hlen;
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__wsum partial;
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bool need_ipsec;
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if (unlikely(!pskb_may_pull(skb, tnl_hlen)))
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goto out;
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/* Adjust partial header checksum to negate old length.
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* We cannot rely on the value contained in uh->len as it is
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* possible that the actual value exceeds the boundaries of the
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* 16 bit length field due to the header being added outside of an
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* IP or IPv6 frame that was already limited to 64K - 1.
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*/
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if (skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)
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partial = (__force __wsum)uh->len;
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else
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partial = (__force __wsum)htonl(skb->len);
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partial = csum_sub(csum_unfold(uh->check), partial);
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/* setup inner skb. */
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skb->encapsulation = 0;
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SKB_GSO_CB(skb)->encap_level = 0;
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__skb_pull(skb, tnl_hlen);
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skb_reset_mac_header(skb);
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skb_set_network_header(skb, skb_inner_network_offset(skb));
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skb_set_transport_header(skb, skb_inner_transport_offset(skb));
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skb->mac_len = skb_inner_network_offset(skb);
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skb->protocol = new_protocol;
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need_csum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM);
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skb->encap_hdr_csum = need_csum;
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remcsum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TUNNEL_REMCSUM);
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skb->remcsum_offload = remcsum;
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need_ipsec = skb_dst(skb) && dst_xfrm(skb_dst(skb));
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/* Try to offload checksum if possible */
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offload_csum = !!(need_csum &&
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!need_ipsec &&
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(skb->dev->features &
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(is_ipv6 ? (NETIF_F_HW_CSUM | NETIF_F_IPV6_CSUM) :
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(NETIF_F_HW_CSUM | NETIF_F_IP_CSUM))));
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features &= skb->dev->hw_enc_features;
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if (need_csum)
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features &= ~NETIF_F_SCTP_CRC;
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/* The only checksum offload we care about from here on out is the
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* outer one so strip the existing checksum feature flags and
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* instead set the flag based on our outer checksum offload value.
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*/
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if (remcsum) {
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features &= ~NETIF_F_CSUM_MASK;
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if (!need_csum || offload_csum)
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features |= NETIF_F_HW_CSUM;
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}
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/* segment inner packet. */
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segs = gso_inner_segment(skb, features);
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if (IS_ERR_OR_NULL(segs)) {
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skb_gso_error_unwind(skb, protocol, tnl_hlen, mac_offset,
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mac_len);
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goto out;
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}
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gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
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outer_hlen = skb_tnl_header_len(skb);
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udp_offset = outer_hlen - tnl_hlen;
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skb = segs;
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do {
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unsigned int len;
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if (remcsum)
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skb->ip_summed = CHECKSUM_NONE;
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/* Set up inner headers if we are offloading inner checksum */
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if (skb->ip_summed == CHECKSUM_PARTIAL) {
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skb_reset_inner_headers(skb);
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skb->encapsulation = 1;
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}
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skb->mac_len = mac_len;
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skb->protocol = protocol;
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__skb_push(skb, outer_hlen);
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skb_reset_mac_header(skb);
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skb_set_network_header(skb, mac_len);
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skb_set_transport_header(skb, udp_offset);
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len = skb->len - udp_offset;
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uh = udp_hdr(skb);
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/* If we are only performing partial GSO the inner header
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* will be using a length value equal to only one MSS sized
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* segment instead of the entire frame.
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*/
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if (gso_partial && skb_is_gso(skb)) {
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uh->len = htons(skb_shinfo(skb)->gso_size +
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SKB_GSO_CB(skb)->data_offset +
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skb->head - (unsigned char *)uh);
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} else {
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uh->len = htons(len);
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}
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if (!need_csum)
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continue;
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uh->check = ~csum_fold(csum_add(partial,
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(__force __wsum)htonl(len)));
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if (skb->encapsulation || !offload_csum) {
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uh->check = gso_make_checksum(skb, ~uh->check);
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if (uh->check == 0)
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uh->check = CSUM_MANGLED_0;
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} else {
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skb->ip_summed = CHECKSUM_PARTIAL;
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skb->csum_start = skb_transport_header(skb) - skb->head;
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skb->csum_offset = offsetof(struct udphdr, check);
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}
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} while ((skb = skb->next));
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out:
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return segs;
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}
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struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb,
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netdev_features_t features,
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bool is_ipv6)
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{
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__be16 protocol = skb->protocol;
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const struct net_offload **offloads;
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const struct net_offload *ops;
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struct sk_buff *segs = ERR_PTR(-EINVAL);
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struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb,
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netdev_features_t features);
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rcu_read_lock();
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switch (skb->inner_protocol_type) {
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case ENCAP_TYPE_ETHER:
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protocol = skb->inner_protocol;
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gso_inner_segment = skb_mac_gso_segment;
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break;
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case ENCAP_TYPE_IPPROTO:
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offloads = is_ipv6 ? inet6_offloads : inet_offloads;
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ops = rcu_dereference(offloads[skb->inner_ipproto]);
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if (!ops || !ops->callbacks.gso_segment)
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goto out_unlock;
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gso_inner_segment = ops->callbacks.gso_segment;
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break;
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default:
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goto out_unlock;
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}
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segs = __skb_udp_tunnel_segment(skb, features, gso_inner_segment,
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protocol, is_ipv6);
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out_unlock:
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rcu_read_unlock();
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return segs;
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}
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EXPORT_SYMBOL(skb_udp_tunnel_segment);
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static void __udpv4_gso_segment_csum(struct sk_buff *seg,
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__be32 *oldip, __be32 *newip,
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__be16 *oldport, __be16 *newport)
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{
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struct udphdr *uh;
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struct iphdr *iph;
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if (*oldip == *newip && *oldport == *newport)
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return;
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uh = udp_hdr(seg);
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iph = ip_hdr(seg);
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if (uh->check) {
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inet_proto_csum_replace4(&uh->check, seg, *oldip, *newip,
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true);
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inet_proto_csum_replace2(&uh->check, seg, *oldport, *newport,
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false);
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if (!uh->check)
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uh->check = CSUM_MANGLED_0;
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}
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*oldport = *newport;
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csum_replace4(&iph->check, *oldip, *newip);
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*oldip = *newip;
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}
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static struct sk_buff *__udpv4_gso_segment_list_csum(struct sk_buff *segs)
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{
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struct sk_buff *seg;
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struct udphdr *uh, *uh2;
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struct iphdr *iph, *iph2;
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seg = segs;
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uh = udp_hdr(seg);
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iph = ip_hdr(seg);
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if ((udp_hdr(seg)->dest == udp_hdr(seg->next)->dest) &&
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(udp_hdr(seg)->source == udp_hdr(seg->next)->source) &&
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(ip_hdr(seg)->daddr == ip_hdr(seg->next)->daddr) &&
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(ip_hdr(seg)->saddr == ip_hdr(seg->next)->saddr))
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return segs;
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while ((seg = seg->next)) {
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uh2 = udp_hdr(seg);
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iph2 = ip_hdr(seg);
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__udpv4_gso_segment_csum(seg,
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&iph2->saddr, &iph->saddr,
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&uh2->source, &uh->source);
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__udpv4_gso_segment_csum(seg,
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&iph2->daddr, &iph->daddr,
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&uh2->dest, &uh->dest);
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}
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return segs;
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}
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static struct sk_buff *__udp_gso_segment_list(struct sk_buff *skb,
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netdev_features_t features,
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bool is_ipv6)
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{
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unsigned int mss = skb_shinfo(skb)->gso_size;
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skb = skb_segment_list(skb, features, skb_mac_header_len(skb));
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if (IS_ERR(skb))
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return skb;
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udp_hdr(skb)->len = htons(sizeof(struct udphdr) + mss);
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return is_ipv6 ? skb : __udpv4_gso_segment_list_csum(skb);
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}
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struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
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netdev_features_t features, bool is_ipv6)
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{
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struct sock *sk = gso_skb->sk;
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unsigned int sum_truesize = 0;
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struct sk_buff *segs, *seg;
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struct udphdr *uh;
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unsigned int mss;
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bool copy_dtor;
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__sum16 check;
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__be16 newlen;
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if (skb_shinfo(gso_skb)->gso_type & SKB_GSO_FRAGLIST)
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return __udp_gso_segment_list(gso_skb, features, is_ipv6);
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mss = skb_shinfo(gso_skb)->gso_size;
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if (gso_skb->len <= sizeof(*uh) + mss)
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return ERR_PTR(-EINVAL);
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skb_pull(gso_skb, sizeof(*uh));
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/* clear destructor to avoid skb_segment assigning it to tail */
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copy_dtor = gso_skb->destructor == sock_wfree;
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if (copy_dtor)
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gso_skb->destructor = NULL;
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segs = skb_segment(gso_skb, features);
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if (IS_ERR_OR_NULL(segs)) {
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if (copy_dtor)
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gso_skb->destructor = sock_wfree;
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return segs;
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}
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/* GSO partial and frag_list segmentation only requires splitting
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* the frame into an MSS multiple and possibly a remainder, both
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* cases return a GSO skb. So update the mss now.
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*/
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if (skb_is_gso(segs))
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mss *= skb_shinfo(segs)->gso_segs;
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seg = segs;
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uh = udp_hdr(seg);
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/* preserve TX timestamp flags and TS key for first segment */
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skb_shinfo(seg)->tskey = skb_shinfo(gso_skb)->tskey;
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skb_shinfo(seg)->tx_flags |=
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(skb_shinfo(gso_skb)->tx_flags & SKBTX_ANY_TSTAMP);
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/* compute checksum adjustment based on old length versus new */
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newlen = htons(sizeof(*uh) + mss);
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check = csum16_add(csum16_sub(uh->check, uh->len), newlen);
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for (;;) {
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if (copy_dtor) {
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seg->destructor = sock_wfree;
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seg->sk = sk;
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sum_truesize += seg->truesize;
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}
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if (!seg->next)
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break;
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uh->len = newlen;
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uh->check = check;
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if (seg->ip_summed == CHECKSUM_PARTIAL)
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gso_reset_checksum(seg, ~check);
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else
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uh->check = gso_make_checksum(seg, ~check) ? :
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CSUM_MANGLED_0;
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seg = seg->next;
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uh = udp_hdr(seg);
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}
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/* last packet can be partial gso_size, account for that in checksum */
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newlen = htons(skb_tail_pointer(seg) - skb_transport_header(seg) +
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seg->data_len);
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check = csum16_add(csum16_sub(uh->check, uh->len), newlen);
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uh->len = newlen;
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uh->check = check;
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if (seg->ip_summed == CHECKSUM_PARTIAL)
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gso_reset_checksum(seg, ~check);
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else
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uh->check = gso_make_checksum(seg, ~check) ? : CSUM_MANGLED_0;
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/* update refcount for the packet */
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if (copy_dtor) {
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int delta = sum_truesize - gso_skb->truesize;
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/* In some pathological cases, delta can be negative.
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* We need to either use refcount_add() or refcount_sub_and_test()
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*/
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if (likely(delta >= 0))
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refcount_add(delta, &sk->sk_wmem_alloc);
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else
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WARN_ON_ONCE(refcount_sub_and_test(-delta, &sk->sk_wmem_alloc));
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}
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return segs;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__udp_gso_segment);
|
|
|
|
static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
|
|
netdev_features_t features)
|
|
{
|
|
struct sk_buff *segs = ERR_PTR(-EINVAL);
|
|
unsigned int mss;
|
|
__wsum csum;
|
|
struct udphdr *uh;
|
|
struct iphdr *iph;
|
|
|
|
if (skb->encapsulation &&
|
|
(skb_shinfo(skb)->gso_type &
|
|
(SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM))) {
|
|
segs = skb_udp_tunnel_segment(skb, features, false);
|
|
goto out;
|
|
}
|
|
|
|
if (!(skb_shinfo(skb)->gso_type & (SKB_GSO_UDP | SKB_GSO_UDP_L4)))
|
|
goto out;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct udphdr)))
|
|
goto out;
|
|
|
|
if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4)
|
|
return __udp_gso_segment(skb, features, false);
|
|
|
|
mss = skb_shinfo(skb)->gso_size;
|
|
if (unlikely(skb->len <= mss))
|
|
goto out;
|
|
|
|
/* Do software UFO. Complete and fill in the UDP checksum as
|
|
* HW cannot do checksum of UDP packets sent as multiple
|
|
* IP fragments.
|
|
*/
|
|
|
|
uh = udp_hdr(skb);
|
|
iph = ip_hdr(skb);
|
|
|
|
uh->check = 0;
|
|
csum = skb_checksum(skb, 0, skb->len, 0);
|
|
uh->check = udp_v4_check(skb->len, iph->saddr, iph->daddr, csum);
|
|
if (uh->check == 0)
|
|
uh->check = CSUM_MANGLED_0;
|
|
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
/* If there is no outer header we can fake a checksum offload
|
|
* due to the fact that we have already done the checksum in
|
|
* software prior to segmenting the frame.
|
|
*/
|
|
if (!skb->encap_hdr_csum)
|
|
features |= NETIF_F_HW_CSUM;
|
|
|
|
/* Fragment the skb. IP headers of the fragments are updated in
|
|
* inet_gso_segment()
|
|
*/
|
|
segs = skb_segment(skb, features);
|
|
out:
|
|
return segs;
|
|
}
|
|
|
|
#define UDP_GRO_CNT_MAX 64
|
|
static struct sk_buff *udp_gro_receive_segment(struct list_head *head,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct udphdr *uh = udp_gro_udphdr(skb);
|
|
struct sk_buff *pp = NULL;
|
|
struct udphdr *uh2;
|
|
struct sk_buff *p;
|
|
unsigned int ulen;
|
|
int ret = 0;
|
|
|
|
/* requires non zero csum, for symmetry with GSO */
|
|
if (!uh->check) {
|
|
NAPI_GRO_CB(skb)->flush = 1;
|
|
return NULL;
|
|
}
|
|
|
|
/* Do not deal with padded or malicious packets, sorry ! */
|
|
ulen = ntohs(uh->len);
|
|
if (ulen <= sizeof(*uh) || ulen != skb_gro_len(skb)) {
|
|
NAPI_GRO_CB(skb)->flush = 1;
|
|
return NULL;
|
|
}
|
|
/* pull encapsulating udp header */
|
|
skb_gro_pull(skb, sizeof(struct udphdr));
|
|
|
|
list_for_each_entry(p, head, list) {
|
|
if (!NAPI_GRO_CB(p)->same_flow)
|
|
continue;
|
|
|
|
uh2 = udp_hdr(p);
|
|
|
|
/* Match ports only, as csum is always non zero */
|
|
if ((*(u32 *)&uh->source != *(u32 *)&uh2->source)) {
|
|
NAPI_GRO_CB(p)->same_flow = 0;
|
|
continue;
|
|
}
|
|
|
|
if (NAPI_GRO_CB(skb)->is_flist != NAPI_GRO_CB(p)->is_flist) {
|
|
NAPI_GRO_CB(skb)->flush = 1;
|
|
return p;
|
|
}
|
|
|
|
/* Terminate the flow on len mismatch or if it grow "too much".
|
|
* Under small packet flood GRO count could elsewhere grow a lot
|
|
* leading to excessive truesize values.
|
|
* On len mismatch merge the first packet shorter than gso_size,
|
|
* otherwise complete the GRO packet.
|
|
*/
|
|
if (ulen > ntohs(uh2->len)) {
|
|
pp = p;
|
|
} else {
|
|
if (NAPI_GRO_CB(skb)->is_flist) {
|
|
if (!pskb_may_pull(skb, skb_gro_offset(skb))) {
|
|
NAPI_GRO_CB(skb)->flush = 1;
|
|
return NULL;
|
|
}
|
|
if ((skb->ip_summed != p->ip_summed) ||
|
|
(skb->csum_level != p->csum_level)) {
|
|
NAPI_GRO_CB(skb)->flush = 1;
|
|
return NULL;
|
|
}
|
|
ret = skb_gro_receive_list(p, skb);
|
|
} else {
|
|
skb_gro_postpull_rcsum(skb, uh,
|
|
sizeof(struct udphdr));
|
|
|
|
ret = skb_gro_receive(p, skb);
|
|
}
|
|
}
|
|
|
|
if (ret || ulen != ntohs(uh2->len) ||
|
|
NAPI_GRO_CB(p)->count >= UDP_GRO_CNT_MAX)
|
|
pp = p;
|
|
|
|
return pp;
|
|
}
|
|
|
|
/* mismatch, but we never need to flush */
|
|
return NULL;
|
|
}
|
|
|
|
struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
|
|
struct udphdr *uh, struct sock *sk)
|
|
{
|
|
struct sk_buff *pp = NULL;
|
|
struct sk_buff *p;
|
|
struct udphdr *uh2;
|
|
unsigned int off = skb_gro_offset(skb);
|
|
int flush = 1;
|
|
|
|
NAPI_GRO_CB(skb)->is_flist = 0;
|
|
if (skb->dev->features & NETIF_F_GRO_FRAGLIST)
|
|
NAPI_GRO_CB(skb)->is_flist = sk ? !udp_sk(sk)->gro_enabled: 1;
|
|
|
|
if ((!sk && (skb->dev->features & NETIF_F_GRO_UDP_FWD)) ||
|
|
(sk && udp_sk(sk)->gro_enabled) || NAPI_GRO_CB(skb)->is_flist) {
|
|
pp = call_gro_receive(udp_gro_receive_segment, head, skb);
|
|
return pp;
|
|
}
|
|
|
|
if (!sk || NAPI_GRO_CB(skb)->encap_mark ||
|
|
(uh->check && skb->ip_summed != CHECKSUM_PARTIAL &&
|
|
NAPI_GRO_CB(skb)->csum_cnt == 0 &&
|
|
!NAPI_GRO_CB(skb)->csum_valid) ||
|
|
!udp_sk(sk)->gro_receive)
|
|
goto out;
|
|
|
|
/* mark that this skb passed once through the tunnel gro layer */
|
|
NAPI_GRO_CB(skb)->encap_mark = 1;
|
|
|
|
flush = 0;
|
|
|
|
list_for_each_entry(p, head, list) {
|
|
if (!NAPI_GRO_CB(p)->same_flow)
|
|
continue;
|
|
|
|
uh2 = (struct udphdr *)(p->data + off);
|
|
|
|
/* Match ports and either checksums are either both zero
|
|
* or nonzero.
|
|
*/
|
|
if ((*(u32 *)&uh->source != *(u32 *)&uh2->source) ||
|
|
(!uh->check ^ !uh2->check)) {
|
|
NAPI_GRO_CB(p)->same_flow = 0;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
skb_gro_pull(skb, sizeof(struct udphdr)); /* pull encapsulating udp header */
|
|
skb_gro_postpull_rcsum(skb, uh, sizeof(struct udphdr));
|
|
pp = call_gro_receive_sk(udp_sk(sk)->gro_receive, sk, head, skb);
|
|
|
|
out:
|
|
skb_gro_flush_final(skb, pp, flush);
|
|
return pp;
|
|
}
|
|
EXPORT_SYMBOL(udp_gro_receive);
|
|
|
|
static struct sock *udp4_gro_lookup_skb(struct sk_buff *skb, __be16 sport,
|
|
__be16 dport)
|
|
{
|
|
const struct iphdr *iph = skb_gro_network_header(skb);
|
|
|
|
return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport,
|
|
iph->daddr, dport, inet_iif(skb),
|
|
inet_sdif(skb), &udp_table, NULL);
|
|
}
|
|
|
|
INDIRECT_CALLABLE_SCOPE
|
|
struct sk_buff *udp4_gro_receive(struct list_head *head, struct sk_buff *skb)
|
|
{
|
|
struct udphdr *uh = udp_gro_udphdr(skb);
|
|
struct sock *sk = NULL;
|
|
struct sk_buff *pp;
|
|
|
|
if (unlikely(!uh))
|
|
goto flush;
|
|
|
|
/* Don't bother verifying checksum if we're going to flush anyway. */
|
|
if (NAPI_GRO_CB(skb)->flush)
|
|
goto skip;
|
|
|
|
if (skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check,
|
|
inet_gro_compute_pseudo))
|
|
goto flush;
|
|
else if (uh->check)
|
|
skb_gro_checksum_try_convert(skb, IPPROTO_UDP,
|
|
inet_gro_compute_pseudo);
|
|
skip:
|
|
NAPI_GRO_CB(skb)->is_ipv6 = 0;
|
|
rcu_read_lock();
|
|
|
|
if (static_branch_unlikely(&udp_encap_needed_key))
|
|
sk = udp4_gro_lookup_skb(skb, uh->source, uh->dest);
|
|
|
|
pp = udp_gro_receive(head, skb, uh, sk);
|
|
rcu_read_unlock();
|
|
return pp;
|
|
|
|
flush:
|
|
NAPI_GRO_CB(skb)->flush = 1;
|
|
return NULL;
|
|
}
|
|
|
|
static int udp_gro_complete_segment(struct sk_buff *skb)
|
|
{
|
|
struct udphdr *uh = udp_hdr(skb);
|
|
|
|
skb->csum_start = (unsigned char *)uh - skb->head;
|
|
skb->csum_offset = offsetof(struct udphdr, check);
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
|
|
skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count;
|
|
skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_L4;
|
|
return 0;
|
|
}
|
|
|
|
int udp_gro_complete(struct sk_buff *skb, int nhoff,
|
|
udp_lookup_t lookup)
|
|
{
|
|
__be16 newlen = htons(skb->len - nhoff);
|
|
struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
|
|
struct sock *sk;
|
|
int err;
|
|
|
|
uh->len = newlen;
|
|
|
|
rcu_read_lock();
|
|
sk = INDIRECT_CALL_INET(lookup, udp6_lib_lookup_skb,
|
|
udp4_lib_lookup_skb, skb, uh->source, uh->dest);
|
|
if (sk && udp_sk(sk)->gro_complete) {
|
|
skb_shinfo(skb)->gso_type = uh->check ? SKB_GSO_UDP_TUNNEL_CSUM
|
|
: SKB_GSO_UDP_TUNNEL;
|
|
|
|
/* Set encapsulation before calling into inner gro_complete()
|
|
* functions to make them set up the inner offsets.
|
|
*/
|
|
skb->encapsulation = 1;
|
|
err = udp_sk(sk)->gro_complete(sk, skb,
|
|
nhoff + sizeof(struct udphdr));
|
|
} else {
|
|
err = udp_gro_complete_segment(skb);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (skb->remcsum_offload)
|
|
skb_shinfo(skb)->gso_type |= SKB_GSO_TUNNEL_REMCSUM;
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(udp_gro_complete);
|
|
|
|
INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff)
|
|
{
|
|
const struct iphdr *iph = ip_hdr(skb);
|
|
struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
|
|
|
|
if (NAPI_GRO_CB(skb)->is_flist) {
|
|
uh->len = htons(skb->len - nhoff);
|
|
|
|
skb_shinfo(skb)->gso_type |= (SKB_GSO_FRAGLIST|SKB_GSO_UDP_L4);
|
|
skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count;
|
|
|
|
if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
|
|
if (skb->csum_level < SKB_MAX_CSUM_LEVEL)
|
|
skb->csum_level++;
|
|
} else {
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
skb->csum_level = 0;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
if (uh->check)
|
|
uh->check = ~udp_v4_check(skb->len - nhoff, iph->saddr,
|
|
iph->daddr, 0);
|
|
|
|
return udp_gro_complete(skb, nhoff, udp4_lib_lookup_skb);
|
|
}
|
|
|
|
static const struct net_offload udpv4_offload = {
|
|
.callbacks = {
|
|
.gso_segment = udp4_ufo_fragment,
|
|
.gro_receive = udp4_gro_receive,
|
|
.gro_complete = udp4_gro_complete,
|
|
},
|
|
};
|
|
|
|
int __init udpv4_offload_init(void)
|
|
{
|
|
return inet_add_offload(&udpv4_offload, IPPROTO_UDP);
|
|
}
|