diff options
Diffstat (limited to 'net/ipv4/ip_output.c')
-rw-r--r-- | net/ipv4/ip_output.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index d2a8f8bb78a6..8ebe86dd72af 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -430,7 +430,7 @@ static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from) * single device frame, and queue such a frame for sending. */ -int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*)) +int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) { struct iphdr *iph; int raw = 0; @@ -720,7 +720,7 @@ static inline int ip_ufo_append_data(struct sock *sk, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int hh_len, int fragheaderlen, - int transhdrlen, int mtu,unsigned int flags) + int transhdrlen, int mtu, unsigned int flags) { struct sk_buff *skb; int err; @@ -741,7 +741,7 @@ static inline int ip_ufo_append_data(struct sock *sk, skb_reserve(skb, hh_len); /* create space for UDP/IP header */ - skb_put(skb,fragheaderlen + transhdrlen); + skb_put(skb, fragheaderlen + transhdrlen); /* initialize network header pointer */ skb_reset_network_header(skb); @@ -778,7 +778,7 @@ int ip_append_data(struct sock *sk, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, - struct ipcm_cookie *ipc, struct rtable *rt, + struct ipcm_cookie *ipc, struct rtable **rtp, unsigned int flags) { struct inet_sock *inet = inet_sk(sk); @@ -793,6 +793,7 @@ int ip_append_data(struct sock *sk, int offset = 0; unsigned int maxfraglen, fragheaderlen; int csummode = CHECKSUM_NONE; + struct rtable *rt; if (flags&MSG_PROBE) return 0; @@ -812,7 +813,11 @@ int ip_append_data(struct sock *sk, inet->cork.flags |= IPCORK_OPT; inet->cork.addr = ipc->addr; } - dst_hold(&rt->u.dst); + rt = *rtp; + /* + * We steal reference to this route, caller should not release it + */ + *rtp = NULL; inet->cork.fragsize = mtu = inet->pmtudisc == IP_PMTUDISC_PROBE ? rt->u.dst.dev->mtu : dst_mtu(rt->u.dst.path); @@ -1279,7 +1284,12 @@ int ip_push_pending_frames(struct sock *sk) skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; - skb->dst = dst_clone(&rt->u.dst); + /* + * Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec + * on dst refcount + */ + inet->cork.dst = NULL; + skb->dst = &rt->u.dst; if (iph->protocol == IPPROTO_ICMP) icmp_out_count(net, ((struct icmphdr *) @@ -1391,7 +1401,7 @@ void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *ar sk->sk_protocol = ip_hdr(skb)->protocol; sk->sk_bound_dev_if = arg->bound_dev_if; ip_append_data(sk, ip_reply_glue_bits, arg->iov->iov_base, len, 0, - &ipc, rt, MSG_DONTWAIT); + &ipc, &rt, MSG_DONTWAIT); if ((skb = skb_peek(&sk->sk_write_queue)) != NULL) { if (arg->csumoffset >= 0) *((__sum16 *)skb_transport_header(skb) + |