10 files changed, 44 insertions, 36 deletions

diff --git a/net/ipv4/gre_demux.c b/net/ipv4/gre_demux.c
index 4e9619bca732..0485bf7f8f03 100644
--- a/net/ipv4/gre_demux.c
+++ b/net/ipv4/gre_demux.c
@@ -68,6 +68,7 @@ void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
 
         skb_push(skb, hdr_len);
 
+        skb_reset_transport_header(skb);
         greh = (struct gre_base_hdr *)skb->data;
         greh->flags = tnl_flags_to_gre_flags(tpi->flags);
         greh->protocol = tpi->proto;
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 79c3d947a481..42b7bcf8045b 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -739,8 +739,6 @@ static void icmp_unreach(struct sk_buff *skb)
                                 /* fall through */
                         case 0:
                                 info = ntohs(icmph->un.frag.mtu);
-                                if (!info)
-                                        goto out;
                         }
                         break;
                 case ICMP_SR_FAILED:
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 6748d420f714..db710b059bab 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1944,6 +1944,10 @@ int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
 
         rtnl_lock();
         in_dev = ip_mc_find_dev(net, imr);
+        if (!in_dev) {
+                ret = -ENODEV;
+                goto out;
+        }
         ifindex = imr->imr_ifindex;
         for (imlp = &inet->mc_list;
              (iml = rtnl_dereference(*imlp)) != NULL;
@@ -1961,16 +1965,14 @@ int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
 
                 *imlp = iml->next_rcu;
 
-                if (in_dev)
-                        ip_mc_dec_group(in_dev, group);
+                ip_mc_dec_group(in_dev, group);
                 rtnl_unlock();
                 /* decrease mem now to avoid the memleak warning */
                 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
                 kfree_rcu(iml, rcu);
                 return 0;
         }
-        if (!in_dev)
-                ret = -ENODEV;
+out:
         rtnl_unlock();
         return ret;
 }
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 097b3e7c1e8f..6f9de61dce5f 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -73,12 +73,7 @@ static void __tunnel_dst_set(struct ip_tunnel_dst *idst,
 {
         struct dst_entry *old_dst;
 
-        if (dst) {
-                if (dst->flags & DST_NOCACHE)
-                        dst = NULL;
-                else
-                        dst_clone(dst);
-        }
+        dst_clone(dst);
         old_dst = xchg((__force struct dst_entry **)&idst->dst, dst);
         dst_release(old_dst);
 }
@@ -108,13 +103,14 @@ static struct rtable *tunnel_rtable_get(struct ip_tunnel *t, u32 cookie)
 
         rcu_read_lock();
         dst = rcu_dereference(this_cpu_ptr(t->dst_cache)->dst);
+        if (dst && !atomic_inc_not_zero(&dst->__refcnt))
+                dst = NULL;
         if (dst) {
                 if (dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
-                        rcu_read_unlock();
                         tunnel_dst_reset(t);
-                        return NULL;
+                        dst_release(dst);
+                        dst = NULL;
                 }
-                dst_hold(dst);
         }
         rcu_read_unlock();
         return (struct rtable *)dst;
@@ -173,6 +169,7 @@ struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 
         hlist_for_each_entry_rcu(t, head, hash_node) {
                 if (remote != t->parms.iph.daddr ||
+                    t->parms.iph.saddr != 0 ||
                     !(t->dev->flags & IFF_UP))
                         continue;
 
@@ -189,10 +186,11 @@ struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
         head = &itn->tunnels[hash];
 
         hlist_for_each_entry_rcu(t, head, hash_node) {
-                if ((local != t->parms.iph.saddr &&
-                     (local != t->parms.iph.daddr ||
-                      !ipv4_is_multicast(local))) ||
-                    !(t->dev->flags & IFF_UP))
+                if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) &&
+                    (local != t->parms.iph.daddr || !ipv4_is_multicast(local)))
+                        continue;
+
+                if (!(t->dev->flags & IFF_UP))
                         continue;
 
                 if (!ip_tunnel_key_match(&t->parms, flags, key))
@@ -209,6 +207,8 @@ struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 
         hlist_for_each_entry_rcu(t, head, hash_node) {
                 if (t->parms.i_key != key ||
+                    t->parms.iph.saddr != 0 ||
+                    t->parms.iph.daddr != 0 ||
                     !(t->dev->flags & IFF_UP))
                         continue;
 
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 082239ffe34a..3162ea923ded 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1010,7 +1010,7 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
         const struct iphdr *iph = (const struct iphdr *) skb->data;
         struct flowi4 fl4;
         struct rtable *rt;
-        struct dst_entry *dst;
+        struct dst_entry *odst = NULL;
         bool new = false;
 
         bh_lock_sock(sk);
@@ -1018,16 +1018,17 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
         if (!ip_sk_accept_pmtu(sk))
                 goto out;
 
-        rt = (struct rtable *) __sk_dst_get(sk);
+        odst = sk_dst_get(sk);
 
-        if (sock_owned_by_user(sk) || !rt) {
+        if (sock_owned_by_user(sk) || !odst) {
                 __ipv4_sk_update_pmtu(skb, sk, mtu);
                 goto out;
         }
 
         __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
 
-        if (!__sk_dst_check(sk, 0)) {
+        rt = (struct rtable *)odst;
+        if (odst->obsolete && odst->ops->check(odst, 0) == NULL) {
                 rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
                 if (IS_ERR(rt))
                         goto out;
@@ -1037,8 +1038,7 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
 
         __ip_rt_update_pmtu((struct rtable *) rt->dst.path, &fl4, mtu);
 
-        dst = dst_check(&rt->dst, 0);
-        if (!dst) {
+        if (!dst_check(&rt->dst, 0)) {
                 if (new)
                         dst_release(&rt->dst);
 
@@ -1050,10 +1050,11 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
         }
 
         if (new)
-                __sk_dst_set(sk, &rt->dst);
+                sk_dst_set(sk, &rt->dst);
 
 out:
         bh_unlock_sock(sk);
+        dst_release(odst);
 }
 EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
 
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index eb1dde37e678..9d2118e5fbc7 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1108,7 +1108,7 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
         if (unlikely(tp->repair)) {
                 if (tp->repair_queue == TCP_RECV_QUEUE) {
                         copied = tcp_send_rcvq(sk, msg, size);
-                        goto out;
+                        goto out_nopush;
                 }
 
                 err = -EINVAL;
@@ -1282,6 +1282,7 @@ wait_for_memory:
 out:
         if (copied)
                 tcp_push(sk, flags, mss_now, tp->nonagle, size_goal);
+out_nopush:
         release_sock(sk);
         return copied + copied_syn;
 
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index 62e48cf84e60..9771563ab564 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -131,7 +131,7 @@ static bool tcp_fastopen_create_child(struct sock *sk,
                                       struct dst_entry *dst,
                                       struct request_sock *req)
 {
-        struct tcp_sock *tp = tcp_sk(sk);
+        struct tcp_sock *tp;
         struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue;
         struct sock *child;
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 40661fc1e233..40639c288dc2 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1106,7 +1106,7 @@ static bool tcp_check_dsack(struct sock *sk, const struct sk_buff *ack_skb,
         }
 
         /* D-SACK for already forgotten data... Do dumb counting. */
-        if (dup_sack && tp->undo_marker && tp->undo_retrans &&
+        if (dup_sack && tp->undo_marker && tp->undo_retrans > 0 &&
             !after(end_seq_0, prior_snd_una) &&
             after(end_seq_0, tp->undo_marker))
                 tp->undo_retrans--;
@@ -1162,7 +1162,7 @@ static int tcp_match_skb_to_sack(struct sock *sk, struct sk_buff *skb,
                         unsigned int new_len = (pkt_len / mss) * mss;
                         if (!in_sack && new_len < pkt_len) {
                                 new_len += mss;
-                                if (new_len > skb->len)
+                                if (new_len >= skb->len)
                                         return 0;
                         }
                         pkt_len = new_len;
@@ -1187,7 +1187,7 @@ static u8 tcp_sacktag_one(struct sock *sk,
 
         /* Account D-SACK for retransmitted packet. */
         if (dup_sack && (sacked & TCPCB_RETRANS)) {
-                if (tp->undo_marker && tp->undo_retrans &&
+                if (tp->undo_marker && tp->undo_retrans > 0 &&
                     after(end_seq, tp->undo_marker))
                         tp->undo_retrans--;
                 if (sacked & TCPCB_SACKED_ACKED)
@@ -1893,7 +1893,7 @@ static void tcp_clear_retrans_partial(struct tcp_sock *tp)
         tp->lost_out = 0;
 
         tp->undo_marker = 0;
-        tp->undo_retrans = 0;
+        tp->undo_retrans = -1;
 }
 
 void tcp_clear_retrans(struct tcp_sock *tp)
@@ -2665,7 +2665,7 @@ static void tcp_enter_recovery(struct sock *sk, bool ece_ack)
 
         tp->prior_ssthresh = 0;
         tp->undo_marker = tp->snd_una;
-        tp->undo_retrans = tp->retrans_out;
+        tp->undo_retrans = tp->retrans_out ? : -1;
 
         if (inet_csk(sk)->icsk_ca_state < TCP_CA_CWR) {
                 if (!ece_ack)
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index d92bce0ea24e..179b51e6bda3 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2525,8 +2525,6 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
                 if (!tp->retrans_stamp)
                         tp->retrans_stamp = TCP_SKB_CB(skb)->when;
 
-                tp->undo_retrans += tcp_skb_pcount(skb);
-
                 /* snd_nxt is stored to detect loss of retransmitted segment,
                  * see tcp_input.c tcp_sacktag_write_queue().
                  */
@@ -2534,6 +2532,10 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
         } else if (err != -EBUSY) {
                 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL);
         }
+
+        if (tp->undo_retrans < 0)
+                tp->undo_retrans = 0;
+        tp->undo_retrans += tcp_skb_pcount(skb);
         return err;
 }
 
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index d92f94b7e402..7d5a8661df76 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1588,8 +1588,11 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
                 goto csum_error;
 
 
-        if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
+        if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
+                UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
+                                 is_udplite);
                 goto drop;
+        }
 
         rc = 0;