kernel-ark/net/sctp/offload.c
Xin Long 5207f39963 sctp: sctp gso should set feature with NETIF_F_SG when calling skb_segment
Now sctp gso puts segments into skb's frag_list, then processes these
segments in skb_segment. But skb_segment handles them only when gs is
enabled, as it's in the same branch with skb's frags.

Although almost all the NICs support sg other than some old ones, but
since commit 1e16aa3ddf ("net: gso: use feature flag argument in all
protocol gso handlers"), features &= skb->dev->hw_enc_features, and
xfrm_output_gso call skb_segment with features = 0, which means sctp
gso would call skb_segment with sg = 0, and skb_segment would not work
as expected.

This patch is to fix it by setting features param with NETIF_F_SG when
calling skb_segment so that it can go the right branch to process the
skb's frag_list.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 12:28:33 -05:00

120 lines
2.7 KiB
C

/*
* sctp_offload - GRO/GSO Offloading for SCTP
*
* Copyright (C) 2015, Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/kprobes.h>
#include <linux/socket.h>
#include <linux/sctp.h>
#include <linux/proc_fs.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/kfifo.h>
#include <linux/time.h>
#include <net/net_namespace.h>
#include <linux/skbuff.h>
#include <net/sctp/sctp.h>
#include <net/sctp/checksum.h>
#include <net/protocol.h>
static __le32 sctp_gso_make_checksum(struct sk_buff *skb)
{
skb->ip_summed = CHECKSUM_NONE;
return sctp_compute_cksum(skb, skb_transport_offset(skb));
}
static struct sk_buff *sctp_gso_segment(struct sk_buff *skb,
netdev_features_t features)
{
struct sk_buff *segs = ERR_PTR(-EINVAL);
struct sctphdr *sh;
sh = sctp_hdr(skb);
if (!pskb_may_pull(skb, sizeof(*sh)))
goto out;
__skb_pull(skb, sizeof(*sh));
if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
/* Packet is from an untrusted source, reset gso_segs. */
struct skb_shared_info *pinfo = skb_shinfo(skb);
struct sk_buff *frag_iter;
pinfo->gso_segs = 0;
if (skb->len != skb->data_len) {
/* Means we have chunks in here too */
pinfo->gso_segs++;
}
skb_walk_frags(skb, frag_iter)
pinfo->gso_segs++;
segs = NULL;
goto out;
}
segs = skb_segment(skb, features | NETIF_F_HW_CSUM | NETIF_F_SG);
if (IS_ERR(segs))
goto out;
/* All that is left is update SCTP CRC if necessary */
if (!(features & NETIF_F_SCTP_CRC)) {
for (skb = segs; skb; skb = skb->next) {
if (skb->ip_summed == CHECKSUM_PARTIAL) {
sh = sctp_hdr(skb);
sh->checksum = sctp_gso_make_checksum(skb);
}
}
}
out:
return segs;
}
static const struct net_offload sctp_offload = {
.callbacks = {
.gso_segment = sctp_gso_segment,
},
};
static const struct net_offload sctp6_offload = {
.callbacks = {
.gso_segment = sctp_gso_segment,
},
};
int __init sctp_offload_init(void)
{
int ret;
ret = inet_add_offload(&sctp_offload, IPPROTO_SCTP);
if (ret)
goto out;
ret = inet6_add_offload(&sctp6_offload, IPPROTO_SCTP);
if (ret)
goto ipv4;
return ret;
ipv4:
inet_del_offload(&sctp_offload, IPPROTO_SCTP);
out:
return ret;
}