inet: frags: add a pointer to struct netns_frags

BugLink: https://bugs.launchpad.net/bugs/1818806

commit 093ba729 upstream.

In order to simplify the API, add a pointer to struct inet_frags.
This will allow us to make things less complex.

These functions no longer have a struct inet_frags parameter :

inet_frag_destroy(struct inet_frag_queue *q  /*, struct inet_frags *f */)
inet_frag_put(struct inet_frag_queue *q /*, struct inet_frags *f */)
inet_frag_kill(struct inet_frag_queue *q /*, struct inet_frags *f */)
inet_frags_exit_net(struct netns_frags *nf /*, struct inet_frags *f */)
ip6_expire_frag_queue(struct net *net, struct frag_queue *fq)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.4: inet_frag_{kill,put}() are called in some
 different places; update all calls]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

include/net/inet_frag.h

@@ -8,6 +8,7 @@ struct netns_frags {
 	int			timeout;
 	int			high_thresh;
 	int			low_thresh;
+	struct inet_frags	*f;
 };
 
 /**
@@ -108,20 +109,20 @@ static inline int inet_frags_init_net(struct netns_frags *nf)
 	atomic_set(&nf->mem, 0);
 	return 0;
 }
-void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);
+void inet_frags_exit_net(struct netns_frags *nf);
 
-void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
-void inet_frag_destroy(struct inet_frag_queue *q, struct inet_frags *f);
+void inet_frag_kill(struct inet_frag_queue *q);
+void inet_frag_destroy(struct inet_frag_queue *q);
 struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
 		struct inet_frags *f, void *key, unsigned int hash);
 
 void inet_frag_maybe_warn_overflow(struct inet_frag_queue *q,
 				   const char *prefix);
 
-static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f)
+static inline void inet_frag_put(struct inet_frag_queue *q)
 {
 	if (atomic_dec_and_test(&q->refcnt))
-		inet_frag_destroy(q, f);
+		inet_frag_destroy(q);
 }
 
 static inline bool inet_frag_evicting(struct inet_frag_queue *q)

include/net/ipv6.h

@@ -534,8 +534,7 @@ struct frag_queue {
 	u8			ecn;
 };
 
-void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
-			   struct inet_frags *frags);
+void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq);
 
 static inline bool ipv6_addr_any(const struct in6_addr *a)
 {

net/ieee802154/6lowpan/reassembly.c

@@ -93,10 +93,10 @@ static void lowpan_frag_expire(unsigned long data)
 	if (fq->q.flags & INET_FRAG_COMPLETE)
 		goto out;
 
-	inet_frag_kill(&fq->q, &lowpan_frags);
+	inet_frag_kill(&fq->q);
 out:
 	spin_unlock(&fq->q.lock);
-	inet_frag_put(&fq->q, &lowpan_frags);
+	inet_frag_put(&fq->q);
 }
 
 static inline struct lowpan_frag_queue *
@@ -229,7 +229,7 @@ static int lowpan_frag_reasm(struct lowpan_frag_queue *fq, struct sk_buff *prev,
 	struct sk_buff *fp, *head = fq->q.fragments;
 	int sum_truesize;
 
-	inet_frag_kill(&fq->q, &lowpan_frags);
+	inet_frag_kill(&fq->q);
 
 	/* Make the one we just received the head. */
 	if (prev) {
@@ -437,7 +437,7 @@ int lowpan_frag_rcv(struct sk_buff *skb, u8 frag_type)
 		ret = lowpan_frag_queue(fq, skb, frag_type);
 		spin_unlock(&fq->q.lock);
 
-		inet_frag_put(&fq->q, &lowpan_frags);
+		inet_frag_put(&fq->q);
 		return ret;
 	}
 
@@ -585,13 +585,14 @@ static int __net_init lowpan_frags_init_net(struct net *net)
 	ieee802154_lowpan->frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
 	ieee802154_lowpan->frags.low_thresh = IPV6_FRAG_LOW_THRESH;
 	ieee802154_lowpan->frags.timeout = IPV6_FRAG_TIMEOUT;
+	ieee802154_lowpan->frags.f = &lowpan_frags;
 
 	res = inet_frags_init_net(&ieee802154_lowpan->frags);
 	if (res < 0)
 		return res;
 	res = lowpan_frags_ns_sysctl_register(net);
 	if (res < 0)
-		inet_frags_exit_net(&ieee802154_lowpan->frags, &lowpan_frags);
+		inet_frags_exit_net(&ieee802154_lowpan->frags);
 	return res;
 }
 
@@ -601,7 +602,7 @@ static void __net_exit lowpan_frags_exit_net(struct net *net)
 		net_ieee802154_lowpan(net);
 
 	lowpan_frags_ns_sysctl_unregister(net);
-	inet_frags_exit_net(&ieee802154_lowpan->frags, &lowpan_frags);
+	inet_frags_exit_net(&ieee802154_lowpan->frags);
 }
 
 static struct pernet_operations lowpan_frags_ops = {

net/ipv4/inet_fragment.c

@@ -219,8 +219,9 @@ void inet_frags_fini(struct inet_frags *f)
 }
 EXPORT_SYMBOL(inet_frags_fini);
 
-void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f)
+void inet_frags_exit_net(struct netns_frags *nf)
 {
+	struct inet_frags *f =nf->f;
 	unsigned int seq;
 	int i;
 
@@ -264,23 +265,23 @@ __acquires(hb->chain_lock)
 	return hb;
 }
 
-static inline void fq_unlink(struct inet_frag_queue *fq, struct inet_frags *f)
+static inline void fq_unlink(struct inet_frag_queue *fq)
 {
 	struct inet_frag_bucket *hb;
 
-	hb = get_frag_bucket_locked(fq, f);
+	hb = get_frag_bucket_locked(fq, fq->net->f);
 	hlist_del(&fq->list);
 	fq->flags |= INET_FRAG_COMPLETE;
 	spin_unlock(&hb->chain_lock);
 }
 
-void inet_frag_kill(struct inet_frag_queue *fq, struct inet_frags *f)
+void inet_frag_kill(struct inet_frag_queue *fq)
 {
 	if (del_timer(&fq->timer))
 		atomic_dec(&fq->refcnt);
 
 	if (!(fq->flags & INET_FRAG_COMPLETE)) {
-		fq_unlink(fq, f);
+		fq_unlink(fq);
 		atomic_dec(&fq->refcnt);
 	}
 }
@@ -294,11 +295,12 @@ static inline void frag_kfree_skb(struct netns_frags *nf, struct inet_frags *f,
 	kfree_skb(skb);
 }
 
-void inet_frag_destroy(struct inet_frag_queue *q, struct inet_frags *f)
+void inet_frag_destroy(struct inet_frag_queue *q)
 {
 	struct sk_buff *fp;
 	struct netns_frags *nf;
 	unsigned int sum, sum_truesize = 0;
+	struct inet_frags *f;
 
 	WARN_ON(!(q->flags & INET_FRAG_COMPLETE));
 	WARN_ON(del_timer(&q->timer) != 0);
@@ -306,6 +308,7 @@ void inet_frag_destroy(struct inet_frag_queue *q, struct inet_frags *f)
 	/* Release all fragment data. */
 	fp = q->fragments;
 	nf = q->net;
+	f = nf->f;
 	while (fp) {
 		struct sk_buff *xp = fp->next;
 
@@ -341,7 +344,7 @@ static struct inet_frag_queue *inet_frag_intern(struct netns_frags *nf,
 			atomic_inc(&qp->refcnt);
 			spin_unlock(&hb->chain_lock);
 			qp_in->flags |= INET_FRAG_COMPLETE;
-			inet_frag_put(qp_in, f);
+			inet_frag_put(qp_in);
 			return qp;
 		}
 	}

net/ipv4/ip_fragment.c

@@ -169,7 +169,7 @@ static void ip4_frag_free(struct inet_frag_queue *q)
 
 static void ipq_put(struct ipq *ipq)
 {
-	inet_frag_put(&ipq->q, &ip4_frags);
+	inet_frag_put(&ipq->q);
 }
 
 /* Kill ipq entry. It is not destroyed immediately,
@@ -177,7 +177,7 @@ static void ipq_put(struct ipq *ipq)
  */
 static void ipq_kill(struct ipq *ipq)
 {
-	inet_frag_kill(&ipq->q, &ip4_frags);
+	inet_frag_kill(&ipq->q);
 }
 
 static bool frag_expire_skip_icmp(u32 user)
@@ -870,19 +870,21 @@ static int __net_init ipv4_frags_init_net(struct net *net)
 	 */
 	net->ipv4.frags.timeout = IP_FRAG_TIME;
 
+	net->ipv4.frags.f = &ip4_frags;
+
 	res = inet_frags_init_net(&net->ipv4.frags);
 	if (res < 0)
 		return res;
 	res = ip4_frags_ns_ctl_register(net);
 	if (res < 0)
-		inet_frags_exit_net(&net->ipv4.frags, &ip4_frags);
+		inet_frags_exit_net(&net->ipv4.frags);
 	return res;
 }
 
 static void __net_exit ipv4_frags_exit_net(struct net *net)
 {
 	ip4_frags_ns_ctl_unregister(net);
-	inet_frags_exit_net(&net->ipv4.frags, &ip4_frags);
+	inet_frags_exit_net(&net->ipv4.frags);
 }
 
 static struct pernet_operations ip4_frags_ops = {

net/ipv6/netfilter/nf_conntrack_reasm.c

@@ -184,7 +184,7 @@ static void nf_ct_frag6_expire(unsigned long data)
 	fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
 	net = container_of(fq->q.net, struct net, nf_frag.frags);
 
-	ip6_expire_frag_queue(net, fq, &nf_frags);
+	ip6_expire_frag_queue(net, fq);
 }
 
 /* Creation primitives. */
@@ -362,7 +362,7 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
 	return 0;
 
 discard_fq:
-	inet_frag_kill(&fq->q, &nf_frags);
+	inet_frag_kill(&fq->q);
 err:
 	return -1;
 }
@@ -383,7 +383,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct net_device *dev)
 	int    payload_len;
 	u8 ecn;
 
-	inet_frag_kill(&fq->q, &nf_frags);
+	inet_frag_kill(&fq->q);
 
 	WARN_ON(head == NULL);
 	WARN_ON(NFCT_FRAG6_CB(head)->offset != 0);
@@ -614,7 +614,7 @@ struct sk_buff *nf_ct_frag6_gather(struct net *net, struct sk_buff *skb, u32 use
 	if (nf_ct_frag6_queue(fq, clone, fhdr, nhoff) < 0) {
 		spin_unlock_bh(&fq->q.lock);
 		pr_debug("Can't insert skb to queue\n");
-		inet_frag_put(&fq->q, &nf_frags);
+		inet_frag_put(&fq->q);
 		goto ret_orig;
 	}
 
@@ -626,7 +626,7 @@ struct sk_buff *nf_ct_frag6_gather(struct net *net, struct sk_buff *skb, u32 use
 	}
 	spin_unlock_bh(&fq->q.lock);
 
-	inet_frag_put(&fq->q, &nf_frags);
+	inet_frag_put(&fq->q);
 	return ret_skb;
 
 ret_orig:
@@ -655,19 +655,21 @@ static int nf_ct_net_init(struct net *net)
 	net->nf_frag.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
 	net->nf_frag.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
 	net->nf_frag.frags.timeout = IPV6_FRAG_TIMEOUT;
+	net->nf_frag.frags.f = &nf_frags;
+
 	res = inet_frags_init_net(&net->nf_frag.frags);
 	if (res < 0)
 		return res;
 	res = nf_ct_frag6_sysctl_register(net);
 	if (res < 0)
-		inet_frags_exit_net(&net->nf_frag.frags, &nf_frags);
+		inet_frags_exit_net(&net->nf_frag.frags);
 	return res;
 }
 
 static void nf_ct_net_exit(struct net *net)
 {
 	nf_ct_frags6_sysctl_unregister(net);
-	inet_frags_exit_net(&net->nf_frag.frags, &nf_frags);
+	inet_frags_exit_net(&net->nf_frag.frags);
 }
 
 static struct pernet_operations nf_ct_net_ops = {

net/ipv6/reassembly.c

@@ -128,8 +128,7 @@ void ip6_frag_init(struct inet_frag_queue *q, const void *a)
 }
 EXPORT_SYMBOL(ip6_frag_init);
 
-void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
-			   struct inet_frags *frags)
+void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq)
 {
 	struct net_device *dev = NULL;
 
@@ -138,7 +137,7 @@ void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
 	if (fq->q.flags & INET_FRAG_COMPLETE)
 		goto out;
 
-	inet_frag_kill(&fq->q, frags);
+	inet_frag_kill(&fq->q);
 
 	rcu_read_lock();
 	dev = dev_get_by_index_rcu(net, fq->iif);
@@ -166,7 +165,7 @@ void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
 	rcu_read_unlock();
 out:
 	spin_unlock(&fq->q.lock);
-	inet_frag_put(&fq->q, frags);
+	inet_frag_put(&fq->q);
 }
 EXPORT_SYMBOL(ip6_expire_frag_queue);
 
@@ -178,7 +177,7 @@ static void ip6_frag_expire(unsigned long data)
 	fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
 	net = container_of(fq->q.net, struct net, ipv6.frags);
 
-	ip6_expire_frag_queue(net, fq, &ip6_frags);
+	ip6_expire_frag_queue(net, fq);
 }
 
 static struct frag_queue *
@@ -359,7 +358,7 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
 	return -1;
 
 discard_fq:
-	inet_frag_kill(&fq->q, &ip6_frags);
+	inet_frag_kill(&fq->q);
 err:
 	IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
 			 IPSTATS_MIB_REASMFAILS);
@@ -386,7 +385,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,
 	int sum_truesize;
 	u8 ecn;
 
-	inet_frag_kill(&fq->q, &ip6_frags);
+	inet_frag_kill(&fq->q);
 
 	ecn = ip_frag_ecn_table[fq->ecn];
 	if (unlikely(ecn == 0xff))
@@ -562,7 +561,7 @@ static int ipv6_frag_rcv(struct sk_buff *skb)
 		ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);
 
 		spin_unlock(&fq->q.lock);
-		inet_frag_put(&fq->q, &ip6_frags);
+		inet_frag_put(&fq->q);
 		return ret;
 	}
 
@@ -713,6 +712,7 @@ static int __net_init ipv6_frags_init_net(struct net *net)
 	net->ipv6.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
 	net->ipv6.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
 	net->ipv6.frags.timeout = IPV6_FRAG_TIMEOUT;
+	net->ipv6.frags.f = &ip6_frags;
 
 	res = inet_frags_init_net(&net->ipv6.frags);
 	if (res < 0)
@@ -720,14 +720,14 @@ static int __net_init ipv6_frags_init_net(struct net *net)
 
 	res = ip6_frags_ns_sysctl_register(net);
 	if (res < 0)
-		inet_frags_exit_net(&net->ipv6.frags, &ip6_frags);
+		inet_frags_exit_net(&net->ipv6.frags);
 	return res;
 }
 
 static void __net_exit ipv6_frags_exit_net(struct net *net)
 {
 	ip6_frags_ns_sysctl_unregister(net);
-	inet_frags_exit_net(&net->ipv6.frags, &ip6_frags);
+	inet_frags_exit_net(&net->ipv6.frags);
 }
 
 static struct pernet_operations ip6_frags_ops = {