kernel/linux.git/net/ipv6/udp_offload.c, branch linux-4.20.y

udp: gro behind static key

2018-10-05T18:52:38+00:00

Avoid the socket lookup cost in udp_gro_receive if no socket has a udp tunnel callback configured. udp_sk(sk)->gro_receive requires a registration with setup_udp_tunnel_sock, which enables the static key. Signed-off-by: Willem de Bruijn Acked-by: Paolo Abeni Signed-off-by: David S. Miller

net: Convert GRO SKB handling to list_head.

2018-06-26T02:33:04+00:00

Manage pending per-NAPI GRO packets via list_head. Return an SKB pointer from the GRO receive handlers. When GRO receive handlers return non-NULL, it means that this SKB needs to be completed at this time and removed from the NAPI queue. Several operations are greatly simplified by this transformation, especially timing out the oldest SKB in the list when gro_count exceeds MAX_GRO_SKBS, and napi_gro_flush() which walks the queue in reverse order. Signed-off-by: David S. Miller

udp: Add support for software checksum and GSO_PARTIAL with GSO offload

2018-05-09T02:30:06+00:00

This patch adds support for a software provided checksum and GSO_PARTIAL segmentation support. With this we can offload UDP segmentation on devices that only have partial support for tunnels. Since we are no longer needing the hardware checksum we can drop the checks in the segmentation code that were verifying if it was present. Signed-off-by: Alexander Duyck Acked-by: Willem de Bruijn Signed-off-by: David S. Miller

udp: Do not pass checksum as a parameter to GSO segmentation

2018-05-09T02:30:06+00:00

This patch is meant to allow us to avoid having to recompute the checksum from scratch and have it passed as a parameter. Instead of taking that approach we can take advantage of the fact that the length that was used to compute the existing checksum is included in the UDP header. Finally to avoid the need to invert the result we can just call csum16_add and csum16_sub directly. By doing this we can avoid a number of instructions in the loop that is handling segmentation. Signed-off-by: Alexander Duyck Acked-by: Willem de Bruijn Signed-off-by: David S. Miller

udp: Do not pass MSS as parameter to GSO segmentation

2018-05-09T02:30:06+00:00

There is no point in passing MSS as a parameter for for the GSO segmentation call as it is already available via the shared info for the skb itself. Reviewed-by: Eric Dumazet Acked-by: Willem de Bruijn Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller

udp: add udp gso

2018-04-26T19:07:42+00:00

Implement generic segmentation offload support for udp datagrams. A follow-up patch adds support to the protocol stack to generate such packets. UDP GSO is not UFO. UFO fragments a single large datagram. GSO splits a large payload into a number of discrete UDP datagrams. The implementation adds a GSO type SKB_UDP_GSO_L4 to differentiate it from UFO (SKB_UDP_GSO). IPPROTO_UDPLITE is excluded, as that protocol has no gso handler registered. [ Export __udp_gso_segment for ipv6. -DaveM ] Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller

gso: validate gso_type in GSO handlers

2018-01-22T21:01:30+00:00

Validate gso_type during segmentation as SKB_GSO_DODGY sources may pass packets where the gso_type does not match the contents. Syzkaller was able to enter the SCTP gso handler with a packet of gso_type SKB_GSO_TCPV4. On entry of transport layer gso handlers, verify that the gso_type matches the transport protocol. Fixes: 90017accff61 ("sctp: Add GSO support") Link: http://lkml.kernel.org/r/<001a1137452496ffc305617e5fe0@google.com> Reported-by: syzbot+fee64147a25aecd48055@syzkaller.appspotmail.com Signed-off-by: Willem de Bruijn Acked-by: Jason Wang Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

net: accept UFO datagrams from tuntap and packet

2017-11-23T16:37:35+00:00

Tuntap and similar devices can inject GSO packets. Accept type VIRTIO_NET_HDR_GSO_UDP, even though not generating UFO natively. Processes are expected to use feature negotiation such as TUNSETOFFLOAD to detect supported offload types and refrain from injecting other packets. This process breaks down with live migration: guest kernels do not renegotiate flags, so destination hosts need to expose all features that the source host does. Partially revert the UFO removal from 182e0b6b5846~1..d9d30adf5677. This patch introduces nearly(*) no new code to simplify verification. It brings back verbatim tuntap UFO negotiation, VIRTIO_NET_HDR_GSO_UDP insertion and software UFO segmentation. It does not reinstate protocol stack support, hardware offload (NETIF_F_UFO), SKB_GSO_UDP tunneling in SKB_GSO_SOFTWARE or reception of VIRTIO_NET_HDR_GSO_UDP packets in tuntap. To support SKB_GSO_UDP reappearing in the stack, also reinstate logic in act_csum and openvswitch. Achieve equivalence with v4.13 HEAD by squashing in commit 939912216fa8 ("net: skb_needs_check() removes CHECKSUM_UNNECESSARY check for tx.") and reverting commit 8d63bee643f1 ("net: avoid skb_warn_bad_offload false positives on UFO"). (*) To avoid having to bring back skb_shinfo(skb)->ip6_frag_id, ipv6_proxy_select_ident is changed to return a __be32 and this is assigned directly to the frag_hdr. Also, SKB_GSO_UDP is inserted at the end of the enum to minimize code churn. Tested Booted a v4.13 guest kernel with QEMU. On a host kernel before this patch `ethtool -k eth0` shows UFO disabled. After the patch, it is enabled, same as on a v4.13 host kernel. A UFO packet sent from the guest appears on the tap device: host: nc -l -p -u 8000 & tcpdump -n -i tap0 guest: dd if=/dev/zero of=payload.txt bs=1 count=2000 nc -u 192.16.1.1 8000 < payload.txt Direct tap to tap transmission of VIRTIO_NET_HDR_GSO_UDP succeeds, packets arriving fragmented: ./with_tap_pair.sh ./tap_send_ufo tap0 tap1 (from https://github.com/wdebruij/kerneltools/tree/master/tests) Changes v1 -> v2 - simplified set_offload change (review comment) - documented test procedure Link: http://lkml.kernel.org/r/ Fixes: fb652fdfe837 ("macvlan/macvtap: Remove NETIF_F_UFO advertisement.") Reported-by: Michal Kubecek Signed-off-by: Willem de Bruijn Acked-by: Jason Wang Signed-off-by: David S. Miller

inet: Remove software UFO fragmenting code.

2017-07-17T16:52:58+00:00

Rename udp{4,6}_ufo_fragment() to udp{4,6}_tunnel_segment() and only handle tunnel segmentation. Signed-off-by: David S. Miller

ipv6: Check ip6_find_1stfragopt() return value properly.

2017-05-18T02:54:11+00:00

Do not use unsigned variables to see if it returns a negative error or not. Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options") Reported-by: Julia Lawall Signed-off-by: David S. Miller