system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-07-22 03:01:14 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

net: gro: parse ipv6 ext headers without frag0 invalidation

Browse source 
The existing code always pulls the IPv6 header and sets the transport
offset initially. Then optionally again pulls any extension headers in
ipv6_gso_pull_exthdrs and sets the transport offset again on return from
that call. skb->data is set at the start of the first extension header
before calling ipv6_gso_pull_exthdrs, and must disable the frag0
optimization because that function uses pskb_may_pull/pskb_pull instead of
skb_gro_ helpers. It sets the GRO offset to the TCP header with
skb_gro_pull and sets the transport header. Then returns skb->data to its
position before this block.

This commit introduces a new helper function - ipv6_gro_pull_exthdrs -
which is used in ipv6_gro_receive to pull ipv6 ext headers instead of
ipv6_gso_pull_exthdrs. Thus, there is no modification of skb->data, all
operations use skb_gro_* helpers, and the frag0 fast path can be taken for
IPv6 packets with ext headers.

Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/504130f6-b56c-4dcc-882c-97942c59f5b7@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Richard Gobert 2024-01-03 15:44:21 +01:00 committed by Jakub Kicinski
parent f2e3fc2158
commit dff0b0161a
1 changed files with 41 additions and 10 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

51
net/ipv6/ip6_offload.c
View file

@ -37,6 +37,40 @@
INDIRECT_CALL_L4(cb, f2, f1, head, skb); \
})
static int ipv6_gro_pull_exthdrs(struct sk_buff *skb, int off, int proto)
{
const struct net_offload *ops = NULL;
struct ipv6_opt_hdr *opth;
for (;;) {
int len;
ops = rcu_dereference(inet6_offloads[proto]);
if (unlikely(!ops))
break;
if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
break;
opth = skb_gro_header(skb, off + sizeof(*opth), off);
if (unlikely(!opth))
break;
len = ipv6_optlen(opth);
opth = skb_gro_header(skb, off + len, off);
if (unlikely(!opth))
break;
proto = opth->nexthdr;
off += len;
}
skb_gro_pull(skb, off - skb_network_offset(skb));
return proto;
}
static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
{
const struct net_offload *ops = NULL;
@ -203,28 +237,25 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
goto out;
skb_set_network_header(skb, off);
skb_gro_pull(skb, sizeof(*iph));
skb_set_transport_header(skb, skb_gro_offset(skb));
flush += ntohs(iph->payload_len) != skb_gro_len(skb);
flush += ntohs(iph->payload_len) != skb->len - hlen;
proto = iph->nexthdr;
ops = rcu_dereference(inet6_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive) {
pskb_pull(skb, skb_gro_offset(skb));
skb_gro_frag0_invalidate(skb);
proto = ipv6_gso_pull_exthdrs(skb, proto);
skb_gro_pull(skb, -skb_transport_offset(skb));
skb_reset_transport_header(skb);
__skb_push(skb, skb_gro_offset(skb));
proto = ipv6_gro_pull_exthdrs(skb, hlen, proto);
ops = rcu_dereference(inet6_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive)
goto out;
iph = ipv6_hdr(skb);
iph = skb_gro_network_header(skb);
} else {
skb_gro_pull(skb, sizeof(*iph));
}
skb_set_transport_header(skb, skb_gro_offset(skb));
NAPI_GRO_CB(skb)->proto = proto;
flush--;