1 files changed, 17 insertions, 8 deletions

diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index bbe7f72db9c1..b3cdeec85f1f 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -198,6 +198,7 @@ static void ip_expire(unsigned long arg)
         qp = container_of((struct inet_frag_queue *) arg, struct ipq, q);
         net = container_of(qp->q.net, struct net, ipv4.frags);
 
+        rcu_read_lock();
         spin_lock(&qp->q.lock);
 
         if (qp->q.flags & INET_FRAG_COMPLETE)
@@ -207,7 +208,7 @@ static void ip_expire(unsigned long arg)
         __IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
 
         if (!inet_frag_evicting(&qp->q)) {
-                struct sk_buff *head = qp->q.fragments;
+                struct sk_buff *clone, *head = qp->q.fragments;
                 const struct iphdr *iph;
                 int err;
 
@@ -216,32 +217,40 @@ static void ip_expire(unsigned long arg)
                 if (!(qp->q.flags & INET_FRAG_FIRST_IN) || !qp->q.fragments)
                         goto out;
 
-                rcu_read_lock();
                 head->dev = dev_get_by_index_rcu(net, qp->iif);
                 if (!head->dev)
-                        goto out_rcu_unlock;
+                        goto out;
+
 
                 /* skb has no dst, perform route lookup again */
                 iph = ip_hdr(head);
                 err = ip_route_input_noref(head, iph->daddr, iph->saddr,
                                            iph->tos, head->dev);
                 if (err)
-                        goto out_rcu_unlock;
+                        goto out;
 
                 /* Only an end host needs to send an ICMP
                  * "Fragment Reassembly Timeout" message, per RFC792.
                  */
                 if (frag_expire_skip_icmp(qp->user) &&
                     (skb_rtable(head)->rt_type != RTN_LOCAL))
-                        goto out_rcu_unlock;
+                        goto out;
+
+                clone = skb_clone(head, GFP_ATOMIC);
 
                 /* Send an ICMP "Fragment Reassembly Timeout" message. */
-                icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0);
-out_rcu_unlock:
-                rcu_read_unlock();
+                if (clone) {
+                        spin_unlock(&qp->q.lock);
+                        icmp_send(clone, ICMP_TIME_EXCEEDED,
+                                  ICMP_EXC_FRAGTIME, 0);
+                        consume_skb(clone);
+                        goto out_rcu_unlock;
+                }
         }
 out:
         spin_unlock(&qp->q.lock);
+out_rcu_unlock:
+        rcu_read_unlock();
         ipq_put(qp);
 }