diff options
Diffstat (limited to 'net/ipv6/ip6_output.c')
-rw-r--r-- | net/ipv6/ip6_output.c | 69 |
1 files changed, 40 insertions, 29 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 291a07be5dfb..32583b507c2e 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -56,11 +56,10 @@ #include <net/checksum.h> #include <linux/mroute6.h> -static int ip6_finish_output2(struct sock *sk, struct sk_buff *skb) +static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct net_device *dev = dst->dev; - struct net *net = dev_net(dev); struct neighbour *neigh; struct in6_addr *nexthop; int ret; @@ -126,16 +125,15 @@ static int ip6_finish_output(struct net *net, struct sock *sk, struct sk_buff *s if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) || dst_allfrag(skb_dst(skb)) || (IP6CB(skb)->frag_max_size && skb->len > IP6CB(skb)->frag_max_size)) - return ip6_fragment(sk, skb, ip6_finish_output2); + return ip6_fragment(net, sk, skb, ip6_finish_output2); else - return ip6_finish_output2(sk, skb); + return ip6_finish_output2(net, sk, skb); } -int ip6_output(struct sock *sk, struct sk_buff *skb) +int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb) { struct net_device *dev = skb_dst(skb)->dev; struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb)); - struct net *net = dev_net(dev); if (unlikely(idev->cnf.disable_ipv6)) { IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS); @@ -150,14 +148,16 @@ int ip6_output(struct sock *sk, struct sk_buff *skb) } /* - * xmit an sk_buff (used by TCP, SCTP and DCCP) + * xmit an sk_buff (used by TCP, SCTP and DCCP) + * Note : socket lock is not held for SYNACK packets, but might be modified + * by calls to skb_set_owner_w() and ipv6_local_error(), + * which are using proper atomic operations or spinlocks. */ - -int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, +int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, struct ipv6_txoptions *opt, int tclass) { struct net *net = sock_net(sk); - struct ipv6_pinfo *np = inet6_sk(sk); + const struct ipv6_pinfo *np = inet6_sk(sk); struct in6_addr *first_hop = &fl6->daddr; struct dst_entry *dst = skb_dst(skb); struct ipv6hdr *hdr; @@ -186,7 +186,10 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, } consume_skb(skb); skb = skb2; - skb_set_owner_w(skb, sk); + /* skb_set_owner_w() changes sk->sk_wmem_alloc atomically, + * it is safe to call in our context (socket lock not held) + */ + skb_set_owner_w(skb, (struct sock *)sk); } if (opt->opt_flen) ipv6_push_frag_opts(skb, opt, &proto); @@ -224,13 +227,20 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) { IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_OUT, skb->len); + /* hooks should never assume socket lock is held. + * we promote our socket to non const + */ return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, - net, sk, skb, NULL, dst->dev, - dst_output_okfn); + net, (struct sock *)sk, skb, NULL, dst->dev, + dst_output); } skb->dev = dst->dev; - ipv6_local_error(sk, EMSGSIZE, fl6, mtu); + /* ipv6_local_error() does not require socket lock, + * we promote our socket to non const + */ + ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu); + IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS); kfree_skb(skb); return -EMSGSIZE; @@ -322,7 +332,7 @@ static inline int ip6_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { skb_sender_cpu_clear(skb); - return dst_output(sk, skb); + return dst_output(net, sk, skb); } static unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst) @@ -542,8 +552,8 @@ static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) skb_copy_secmark(to, from); } -int ip6_fragment(struct sock *sk, struct sk_buff *skb, - int (*output)(struct sock *, struct sk_buff *)) +int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, + int (*output)(struct net *, struct sock *, struct sk_buff *)) { struct sk_buff *frag; struct rt6_info *rt = (struct rt6_info *)skb_dst(skb); @@ -556,7 +566,6 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb, __be32 frag_id; int ptr, offset = 0, err = 0; u8 *prevhdr, nexthdr = 0; - struct net *net = dev_net(skb_dst(skb)->dev); hlen = ip6_find_1stfragopt(skb, &prevhdr); nexthdr = *prevhdr; @@ -588,20 +597,22 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb, frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr, &ipv6_hdr(skb)->saddr); + hroom = LL_RESERVED_SPACE(rt->dst.dev); if (skb_has_frag_list(skb)) { int first_len = skb_pagelen(skb); struct sk_buff *frag2; if (first_len - hlen > mtu || ((first_len - hlen) & 7) || - skb_cloned(skb)) + skb_cloned(skb) || + skb_headroom(skb) < (hroom + sizeof(struct frag_hdr))) goto slow_path; skb_walk_frags(skb, frag) { /* Correct geometry. */ if (frag->len > mtu || ((frag->len & 7) && frag->next) || - skb_headroom(frag) < hlen) + skb_headroom(frag) < (hlen + hroom + sizeof(struct frag_hdr))) goto slow_path_clean; /* Partially cloned skb? */ @@ -618,8 +629,6 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb, err = 0; offset = 0; - frag = skb_shinfo(skb)->frag_list; - skb_frag_list_init(skb); /* BUILD HEADER */ *prevhdr = NEXTHDR_FRAGMENT; @@ -627,8 +636,11 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb, if (!tmp_hdr) { IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS); - return -ENOMEM; + err = -ENOMEM; + goto fail; } + frag = skb_shinfo(skb)->frag_list; + skb_frag_list_init(skb); __skb_pull(skb, hlen); fh = (struct frag_hdr *)__skb_push(skb, sizeof(struct frag_hdr)); @@ -673,7 +685,7 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb, ip6_copy_metadata(frag, skb); } - err = output(sk, skb); + err = output(net, sk, skb); if (!err) IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), IPSTATS_MIB_FRAGCREATES); @@ -725,7 +737,6 @@ slow_path: */ *prevhdr = NEXTHDR_FRAGMENT; - hroom = LL_RESERVED_SPACE(rt->dst.dev); troom = rt->dst.dev->needed_tailroom; /* @@ -802,7 +813,7 @@ slow_path: /* * Put this fragment into the sending queue. */ - err = output(sk, frag); + err = output(net, sk, frag); if (err) goto fail; @@ -883,7 +894,7 @@ out: return dst; } -static int ip6_dst_lookup_tail(struct net *net, struct sock *sk, +static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk, struct dst_entry **dst, struct flowi6 *fl6) { #ifdef CONFIG_IPV6_OPTIMISTIC_DAD @@ -1014,7 +1025,7 @@ EXPORT_SYMBOL_GPL(ip6_dst_lookup); * It returns a valid dst pointer on success, or a pointer encoded * error code. */ -struct dst_entry *ip6_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6, +struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6, const struct in6_addr *final_dst) { struct dst_entry *dst = NULL; @@ -1680,7 +1691,7 @@ int ip6_send_skb(struct sk_buff *skb) struct rt6_info *rt = (struct rt6_info *)skb_dst(skb); int err; - err = ip6_local_out(skb); + err = ip6_local_out(net, skb->sk, skb); if (err) { if (err > 0) err = net_xmit_errno(err); |