inet: frags: use INET_FRAG_EVICTED to prevent icmp messages

Now that we have INET_FRAG_EVICTED we might as well use it to stop
sending icmp messages in the "frag_expire" functions instead of
stripping INET_FRAG_FIRST_IN from their flags when evicting.
Also fix the comment style in ip6_expire_frag_queue().

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 15 insertions, 16 deletions

diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c
index fa49916c23a0..4baa76c60398 100644
--- a/net/ipv4/inet_fragment.c
+++ b/net/ipv4/inet_fragment.c
@@ -151,8 +151,6 @@ evict_again:
                         goto evict_again;
                 }
 
-                /* suppress xmit of (icmp) error packet */
-                fq->flags &= ~INET_FRAG_FIRST_IN;
                 fq->flags |= INET_FRAG_EVICTED;
                 hlist_del(&fq->list);
                 hlist_add_head(&fq->list, &expired);
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 6fce1ecc5bca..cb56bcc1eee2 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -189,16 +189,18 @@ static void ip_expire(unsigned long arg)
                 goto out;
 
         ipq_kill(qp);
-
-        if (!(qp->q.flags & INET_FRAG_EVICTED))
-                IP_INC_STATS_BH(net, IPSTATS_MIB_REASMTIMEOUT);
         IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS);
 
-        if ((qp->q.flags & INET_FRAG_FIRST_IN) && qp->q.fragments != NULL) {
+        if (!(qp->q.flags & INET_FRAG_EVICTED)) {
                 struct sk_buff *head = qp->q.fragments;
                 const struct iphdr *iph;
                 int err;
 
+                IP_INC_STATS_BH(net, IPSTATS_MIB_REASMTIMEOUT);
+
+                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)
@@ -211,8 +213,7 @@ static void ip_expire(unsigned long arg)
                 if (err)
                         goto out_rcu_unlock;
 
-                /*
-                 * Only an end host needs to send an ICMP
+                /* Only an end host needs to send an ICMP
                  * "Fragment Reassembly Timeout" message, per RFC792.
                  */
                 if (qp->user == IP_DEFRAG_AF_PACKET ||
@@ -221,7 +222,6 @@ static void ip_expire(unsigned long arg)
                      (skb_rtable(head)->rt_type != RTN_LOCAL)))
                         goto out_rcu_unlock;
 
-
                 /* Send an ICMP "Fragment Reassembly Timeout" message. */
                 icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0);
 out_rcu_unlock:
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index b4baceed0d0d..beb6872a8fa5 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -141,19 +141,20 @@ void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
         if (!dev)
                 goto out_rcu_unlock;
 
-        if (!(fq->q.flags & INET_FRAG_EVICTED))
-                IP6_INC_STATS_BH(net, __in6_dev_get(dev),
-                                 IPSTATS_MIB_REASMTIMEOUT);
         IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
 
+        if (fq->q.flags & INET_FRAG_EVICTED)
+                goto out_rcu_unlock;
+
+        IP6_INC_STATS_BH(net, __in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT);
+
         /* Don't send error if the first segment did not arrive. */
         if (!(fq->q.flags & INET_FRAG_FIRST_IN) || !fq->q.fragments)
                 goto out_rcu_unlock;
 
-        /*
-           But use as source device on which LAST ARRIVED
-           segment was received. And do not use fq->dev
-           pointer directly, device might already disappeared.
+        /* But use as source device on which LAST ARRIVED
+         * segment was received. And do not use fq->dev
+         * pointer directly, device might already disappeared.
          */
         fq->q.fragments->dev = dev;
         icmpv6_send(fq->q.fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0);