kernel/linux.git/net/ipv4/gre_offload.c, branch linux-4.16.y

gso: fix payload length when gso_size is zero

2017-10-08T17:12:15+00:00

When gso_size reset to zero for the tail segment in skb_segment(), later in ipv6_gso_segment(), __skb_udp_tunnel_segment() and gre_gso_segment() we will get incorrect results (payload length, pcsum) for that segment. inet_gso_segment() already has a check for gso_size before calculating payload. The issue was found with LTP vxlan & gre tests over ixgbe NIC. Fixes: 07b26c9454a2 ("gso: Support partial splitting at the frag_list pointer") Signed-off-by: Alexey Kodanev Acked-by: Alexander Duyck Signed-off-by: David S. Miller

net: Remove all references to SKB_GSO_UDP.

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

Such packets are no longer possible. Signed-off-by: David S. Miller

net: add recursion limit to GRO

2016-10-20T18:32:22+00:00

Currently, GRO can do unlimited recursion through the gro_receive handlers. This was fixed for tunneling protocols by limiting tunnel GRO to one level with encap_mark, but both VLAN and TEB still have this problem. Thus, the kernel is vulnerable to a stack overflow, if we receive a packet composed entirely of VLAN headers. This patch adds a recursion counter to the GRO layer to prevent stack overflow. When a gro_receive function hits the recursion limit, GRO is aborted for this skb and it is processed normally. This recursion counter is put in the GRO CB, but could be turned into a percpu counter if we run out of space in the CB. Thanks to Vladimír Beneš for the initial bug report. Fixes: CVE-2016-7039 Fixes: 9b174d88c257 ("net: Add Transparent Ethernet Bridging GRO support.") Fixes: 66e5133f19e9 ("vlan: Add GRO support for non hardware accelerated vlan") Signed-off-by: Sabrina Dubroca Reviewed-by: Jiri Benc Acked-by: Hannes Frederic Sowa Acked-by: Tom Herbert Signed-off-by: David S. Miller

gso: Support partial splitting at the frag_list pointer

2016-09-20T00:59:34+00:00

Since commit 8a29111c7 ("net: gro: allow to build full sized skb") gro may build buffers with a frag_list. This can hurt forwarding because most NICs can't offload such packets, they need to be segmented in software. This patch splits buffers with a frag_list at the frag_list pointer into buffers that can be TSO offloaded. Signed-off-by: Steffen Klassert Acked-by: Alexander Duyck Signed-off-by: David S. Miller

gso: Remove arbitrary checks for unsupported GSO

2016-05-20T22:03:15+00:00

In several gso_segment functions there are checks of gso_type against a seemingly arbitrary list of SKB_GSO_* flags. This seems like an attempt to identify unsupported GSO types, but since the stack is the one that set these GSO types in the first place this seems unnecessary to do. If a combination isn't valid in the first place that stack should not allow setting it. This is a code simplication especially for add new GSO types. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller

GRE: Add support for GRO/GSO of IPv6 GRE traffic

2016-04-16T23:09:13+00:00

Since GRE doesn't really care about L3 protocol we can support IPv4 and IPv6 using the same offloads. With that being the case we can add a call to register the offloads for IPv6 as a part of our GRE offload initialization. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller

GSO: Support partial segmentation offload

2016-04-14T20:23:41+00:00

This patch adds support for something I am referring to as GSO partial. The basic idea is that we can support a broader range of devices for segmentation if we use fixed outer headers and have the hardware only really deal with segmenting the inner header. The idea behind the naming is due to the fact that everything before csum_start will be fixed headers, and everything after will be the region that is handled by hardware. With the current implementation it allows us to add support for the following GSO types with an inner TSO_MANGLEID or TSO6 offload: NETIF_F_GSO_GRE NETIF_F_GSO_GRE_CSUM NETIF_F_GSO_IPIP NETIF_F_GSO_SIT NETIF_F_UDP_TUNNEL NETIF_F_UDP_TUNNEL_CSUM In the case of hardware that already supports tunneling we may be able to extend this further to support TSO_TCPV4 without TSO_MANGLEID if the hardware can support updating inner IPv4 headers. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller

GSO: Add GSO type for fixed IPv4 ID

2016-04-14T20:23:40+00:00

This patch adds support for TSO using IPv4 headers with a fixed IP ID field. This is meant to allow us to do a lossless GRO in the case of TCP flows that use a fixed IP ID such as those that convert IPv6 header to IPv4 headers. In addition I am adding a feature that for now I am referring to TSO with IP ID mangling. Basically when this flag is enabled the device has the option to either output the flow with incrementing IP IDs or with a fixed IP ID regardless of what the original IP ID ordering was. This is useful in cases where the DF bit is set and we do not care if the original IP ID value is maintained. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller

GRE: Disable segmentation offloads w/ CSUM and we are encapsulated via FOU

2016-04-07T20:56:33+00:00

This patch fixes an issue I found in which we were dropping frames if we had enabled checksums on GRE headers that were encapsulated by either FOU or GUE. Without this patch I was barely able to get 1 Gb/s of throughput. With this patch applied I am now at least getting around 6 Gb/s. The issue is due to the fact that with FOU or GUE applied we do not provide a transport offset pointing to the GRE header, nor do we offload it in software as the GRE header is completely skipped by GSO and treated like a VXLAN or GENEVE type header. As such we need to prevent the stack from generating it and also prevent GRE from generating it via any interface we create. Fixes: c3483384ee511 ("gro: Allow tunnel stacking in the case of FOU/GUE") Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller

net: Reset encap_level to avoid resetting features on inner IP headers

2016-03-23T18:19:08+00:00

This patch corrects an oversight in which we were allowing the encap_level value to pass from the outer headers to the inner headers. As a result we were incorrectly identifying UDP or GRE tunnels as also making use of ipip or sit when the second header actually represented a tunnel encapsulated in either a UDP or GRE tunnel which already had the features masked. Fixes: 76443456227097179c1482 ("net: Move GSO csum into SKB_GSO_CB") Reported-by: Tom Herbert Signed-off-by: Alexander Duyck Acked-by: Tom Herbert Signed-off-by: David S. Miller