ipv6: addrconf: Avoid calling netdevice notifiers with RCU read-side lock

[pandora-kernel.git] / net / ipv6 / ip6_output.c

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 84d0bd5..ae98e09 100644 (file)
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -603,7 +603,7 @@ void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt)
        static atomic_t ipv6_fragmentation_id;
        int old, new;
 
-       if (rt) {
+       if (rt && !(rt->dst.flags & DST_NOPEER)) {
                struct inet_peer *peer;
 
                if (!rt->rt6i_peer)
@@ -1178,6 +1178,29 @@ static inline struct ipv6_rt_hdr *ip6_rthdr_dup(struct ipv6_rt_hdr *src,
        return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
 }
 
+static void ip6_append_data_mtu(int *mtu,
+                               int *maxfraglen,
+                               unsigned int fragheaderlen,
+                               struct sk_buff *skb,
+                               struct rt6_info *rt)
+{
+       if (!(rt->dst.flags & DST_XFRM_TUNNEL)) {
+               if (skb == NULL) {
+                       /* first fragment, reserve header_len */
+                       *mtu = *mtu - rt->dst.header_len;
+
+               } else {
+                       /*
+                        * this fragment is not first, the headers
+                        * space is regarded as data space.
+                        */
+                       *mtu = dst_mtu(rt->dst.path);
+               }
+               *maxfraglen = ((*mtu - fragheaderlen) & ~7)
+                             + fragheaderlen - sizeof(struct frag_hdr);
+       }
+}
+
 int ip6_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,
@@ -1187,7 +1210,7 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
        struct inet_sock *inet = inet_sk(sk);
        struct ipv6_pinfo *np = inet6_sk(sk);
        struct inet_cork *cork;
-       struct sk_buff *skb;
+       struct sk_buff *skb, *skb_prev = NULL;
        unsigned int maxfraglen, fragheaderlen;
        int exthdrlen;
        int dst_exthdrlen;
@@ -1245,8 +1268,12 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
                inet->cork.fl.u.ip6 = *fl6;
                np->cork.hop_limit = hlimit;
                np->cork.tclass = tclass;
-               mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
-                     rt->dst.dev->mtu : dst_mtu(&rt->dst);
+               if (rt->dst.flags & DST_XFRM_TUNNEL)
+                       mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
+                             rt->dst.dev->mtu : dst_mtu(&rt->dst);
+               else
+                       mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ?
+                             rt->dst.dev->mtu : dst_mtu(rt->dst.path);
                if (np->frag_size < mtu) {
                        if (np->frag_size)
                                mtu = np->frag_size;
@@ -1342,25 +1369,27 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
                        unsigned int fraglen;
                        unsigned int fraggap;
                        unsigned int alloclen;
-                       struct sk_buff *skb_prev;
 alloc_new_skb:
-                       skb_prev = skb;
-
                        /* There's no room in the current skb */
-                       if (skb_prev)
-                               fraggap = skb_prev->len - maxfraglen;
+                       if (skb)
+                               fraggap = skb->len - maxfraglen;
                        else
                                fraggap = 0;
+                       /* update mtu and maxfraglen if necessary */
+                       if (skb == NULL || skb_prev == NULL)
+                               ip6_append_data_mtu(&mtu, &maxfraglen,
+                                                   fragheaderlen, skb, rt);
+
+                       skb_prev = skb;
 
                        /*
                         * If remaining data exceeds the mtu,
                         * we know we need more fragment(s).
                         */
                        datalen = length + fraggap;
-                       if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
-                               datalen = maxfraglen - fragheaderlen;
 
-                       fraglen = datalen + fragheaderlen;
+                       if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
+                               datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len;
                        if ((flags & MSG_MORE) &&
                            !(rt->dst.dev->features&NETIF_F_SG))
                                alloclen = mtu;
@@ -1369,13 +1398,16 @@ alloc_new_skb:
 
                        alloclen += dst_exthdrlen;
 
-                       /*
-                        * The last fragment gets additional space at tail.
-                        * Note: we overallocate on fragments with MSG_MODE
-                        * because we have no idea if we're the last one.
-                        */
-                       if (datalen == length + fraggap)
-                               alloclen += rt->dst.trailer_len;
+                       if (datalen != length + fraggap) {
+                               /*
+                                * this is not the last fragment, the trailer
+                                * space is regarded as data space.
+                                */
+                               datalen += rt->dst.trailer_len;
+                       }
+
+                       alloclen += rt->dst.trailer_len;
+                       fraglen = datalen + fragheaderlen;
 
                        /*
                         * We just reserve space for fragment header.
@@ -1411,8 +1443,9 @@ alloc_new_skb:
                         */
                        skb->ip_summed = csummode;
                        skb->csum = 0;
-                       /* reserve for fragmentation */
-                       skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
+                       /* reserve for fragmentation and ipsec header */
+                       skb_reserve(skb, hh_len + sizeof(struct frag_hdr) +
+                                   dst_exthdrlen);
 
                        if (sk->sk_type == SOCK_DGRAM)
                                skb_shinfo(skb)->tx_flags = tx_flags;
@@ -1420,9 +1453,9 @@ alloc_new_skb:
                        /*
                         *      Find where to start putting bytes
                         */
-                       data = skb_put(skb, fraglen + dst_exthdrlen);
-                       skb_set_network_header(skb, exthdrlen + dst_exthdrlen);
-                       data += fragheaderlen + dst_exthdrlen;
+                       data = skb_put(skb, fraglen);
+                       skb_set_network_header(skb, exthdrlen);
+                       data += fragheaderlen;
                        skb->transport_header = (skb->network_header +
                                                 fragheaderlen);
                        if (fraggap) {