These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

1 files changed, 74 insertions, 46 deletions

diff --git a/kernel/net/ipv4/ip_fragment.c b/kernel/net/ipv4/ip_fragment.c
index cae22a1a8..b8a0607da 100644
--- a/kernel/net/ipv4/ip_fragment.c
+++ b/kernel/net/ipv4/ip_fragment.c
@@ -48,6 +48,7 @@
 #include <linux/inet.h>
 #include <linux/netfilter_ipv4.h>
 #include <net/inet_ecn.h>
+#include <net/l3mdev.h>
 
 /* NOTE. Logic of IP defragmentation is parallel to corresponding IPv6
  * code now. If you change something here, _PLEASE_ update ipv6/reassembly.c
@@ -75,7 +76,9 @@ struct ipq {
 	__be16		id;
 	u8		protocol;
 	u8		ecn; /* RFC3168 support */
+	u16		max_df_size; /* largest frag with DF set seen */
 	int             iif;
+	int             vif;   /* L3 master device index */
 	unsigned int    rid;
 	struct inet_peer *peer;
 };
@@ -98,6 +101,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
 struct ip4_create_arg {
 	struct iphdr *iph;
 	u32 user;
+	int vif;
 };
 
 static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot)
@@ -126,7 +130,8 @@ static bool ip4_frag_match(const struct inet_frag_queue *q, const void *a)
 		qp->saddr == arg->iph->saddr &&
 		qp->daddr == arg->iph->daddr &&
 		qp->protocol == arg->iph->protocol &&
-		qp->user == arg->user;
+		qp->user == arg->user &&
+		qp->vif == arg->vif;
 }
 
 static void ip4_frag_init(struct inet_frag_queue *q, const void *a)
@@ -143,9 +148,11 @@ static void ip4_frag_init(struct inet_frag_queue *q, const void *a)
 	qp->ecn = ip4_frag_ecn(arg->iph->tos);
 	qp->saddr = arg->iph->saddr;
 	qp->daddr = arg->iph->daddr;
+	qp->vif = arg->vif;
 	qp->user = arg->user;
 	qp->peer = sysctl_ipfrag_max_dist ?
-		inet_getpeer_v4(net->ipv4.peers, arg->iph->saddr, 1) : NULL;
+		inet_getpeer_v4(net->ipv4.peers, arg->iph->saddr, arg->vif, 1) :
+		NULL;
 }
 
 static void ip4_frag_free(struct inet_frag_queue *q)
@@ -173,6 +180,15 @@ static void ipq_kill(struct ipq *ipq)
 	inet_frag_kill(&ipq->q, &ip4_frags);
 }
 
+static bool frag_expire_skip_icmp(u32 user)
+{
+	return user == IP_DEFRAG_AF_PACKET ||
+	       ip_defrag_user_in_between(user, IP_DEFRAG_CONNTRACK_IN,
+					 __IP_DEFRAG_CONNTRACK_IN_END) ||
+	       ip_defrag_user_in_between(user, IP_DEFRAG_CONNTRACK_BRIDGE_IN,
+					 __IP_DEFRAG_CONNTRACK_BRIDGE_IN);
+}
+
 /*
  * Oops, a fragment queue timed out.  Kill it and send an ICMP reply.
  */
@@ -192,7 +208,7 @@ static void ip_expire(unsigned long arg)
 	ipq_kill(qp);
 	IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS);
 
-	if (!(qp->q.flags & INET_FRAG_EVICTED)) {
+	if (!inet_frag_evicting(&qp->q)) {
 		struct sk_buff *head = qp->q.fragments;
 		const struct iphdr *iph;
 		int err;
@@ -217,10 +233,8 @@ static void ip_expire(unsigned long arg)
 		/* Only an end host needs to send an ICMP
 		 * "Fragment Reassembly Timeout" message, per RFC792.
 		 */
-		if (qp->user == IP_DEFRAG_AF_PACKET ||
-		    ((qp->user >= IP_DEFRAG_CONNTRACK_IN) &&
-		     (qp->user <= __IP_DEFRAG_CONNTRACK_IN_END) &&
-		     (skb_rtable(head)->rt_type != RTN_LOCAL)))
+		if (frag_expire_skip_icmp(qp->user) &&
+		    (skb_rtable(head)->rt_type != RTN_LOCAL))
 			goto out_rcu_unlock;
 
 		/* Send an ICMP "Fragment Reassembly Timeout" message. */
@@ -236,7 +250,8 @@ out:
 /* Find the correct entry in the "incomplete datagrams" queue for
  * this IP datagram, and create new one, if nothing is found.
  */
-static struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user)
+static struct ipq *ip_find(struct net *net, struct iphdr *iph,
+			   u32 user, int vif)
 {
 	struct inet_frag_queue *q;
 	struct ip4_create_arg arg;
@@ -244,6 +259,7 @@ static struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user)
 
 	arg.iph = iph;
 	arg.user = user;
+	arg.vif = vif;
 
 	hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol);
 
@@ -301,7 +317,7 @@ static int ip_frag_reinit(struct ipq *qp)
 		kfree_skb(fp);
 		fp = xp;
 	} while (fp);
-	sub_frag_mem_limit(&qp->q, sum_truesize);
+	sub_frag_mem_limit(qp->q.net, sum_truesize);
 
 	qp->q.flags = 0;
 	qp->q.len = 0;
@@ -319,6 +335,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
 {
 	struct sk_buff *prev, *next;
 	struct net_device *dev;
+	unsigned int fragsize;
 	int flags, offset;
 	int ihl, end;
 	int err = -ENOENT;
@@ -446,7 +463,7 @@ found:
 				qp->q.fragments = next;
 
 			qp->q.meat -= free_it->len;
-			sub_frag_mem_limit(&qp->q, free_it->truesize);
+			sub_frag_mem_limit(qp->q.net, free_it->truesize);
 			kfree_skb(free_it);
 		}
 	}
@@ -470,13 +487,18 @@ found:
 	qp->q.stamp = skb->tstamp;
 	qp->q.meat += skb->len;
 	qp->ecn |= ecn;
-	add_frag_mem_limit(&qp->q, skb->truesize);
+	add_frag_mem_limit(qp->q.net, skb->truesize);
 	if (offset == 0)
 		qp->q.flags |= INET_FRAG_FIRST_IN;
 
+	fragsize = skb->len + ihl;
+
+	if (fragsize > qp->q.max_size)
+		qp->q.max_size = fragsize;
+
 	if (ip_hdr(skb)->frag_off & htons(IP_DF) &&
-	    skb->len + ihl > qp->q.max_size)
-		qp->q.max_size = skb->len + ihl;
+	    fragsize > qp->max_df_size)
+		qp->max_df_size = fragsize;
 
 	if (qp->q.flags == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
 	    qp->q.meat == qp->q.len) {
@@ -508,7 +530,6 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
 	int len;
 	int ihlen;
 	int err;
-	int sum_truesize;
 	u8 ecn;
 
 	ipq_kill(qp);
@@ -573,47 +594,47 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
 		head->len -= clone->len;
 		clone->csum = 0;
 		clone->ip_summed = head->ip_summed;
-		add_frag_mem_limit(&qp->q, clone->truesize);
+		add_frag_mem_limit(qp->q.net, clone->truesize);
 	}
 
+	skb_shinfo(head)->frag_list = head->next;
 	skb_push(head, head->data - skb_network_header(head));
 
-	sum_truesize = head->truesize;
-	for (fp = head->next; fp;) {
-		bool headstolen;
-		int delta;
-		struct sk_buff *next = fp->next;
-
-		sum_truesize += fp->truesize;
+	for (fp=head->next; fp; fp = fp->next) {
+		head->data_len += fp->len;
+		head->len += fp->len;
 		if (head->ip_summed != fp->ip_summed)
 			head->ip_summed = CHECKSUM_NONE;
 		else if (head->ip_summed == CHECKSUM_COMPLETE)
 			head->csum = csum_add(head->csum, fp->csum);
-
-		if (skb_try_coalesce(head, fp, &headstolen, &delta)) {
-			kfree_skb_partial(fp, headstolen);
-		} else {
-			if (!skb_shinfo(head)->frag_list)
-				skb_shinfo(head)->frag_list = fp;
-			head->data_len += fp->len;
-			head->len += fp->len;
-			head->truesize += fp->truesize;
-		}
-		fp = next;
+		head->truesize += fp->truesize;
 	}
-	sub_frag_mem_limit(&qp->q, sum_truesize);
+	sub_frag_mem_limit(qp->q.net, head->truesize);
 
 	head->next = NULL;
 	head->dev = dev;
 	head->tstamp = qp->q.stamp;
-	IPCB(head)->frag_max_size = qp->q.max_size;
+	IPCB(head)->frag_max_size = max(qp->max_df_size, qp->q.max_size);
 
 	iph = ip_hdr(head);
-	/* max_size != 0 implies at least one fragment had IP_DF set */
-	iph->frag_off = qp->q.max_size ? htons(IP_DF) : 0;
 	iph->tot_len = htons(len);
 	iph->tos |= ecn;
 
+	/* When we set IP_DF on a refragmented skb we must also force a
+	 * call to ip_fragment to avoid forwarding a DF-skb of size s while
+	 * original sender only sent fragments of size f (where f < s).
+	 *
+	 * We only set DF/IPSKB_FRAG_PMTU if such DF fragment was the largest
+	 * frag seen to avoid sending tiny DF-fragments in case skb was built
+	 * from one very small df-fragment and one large non-df frag.
+	 */
+	if (qp->max_df_size == qp->q.max_size) {
+		IPCB(head)->flags |= IPSKB_FRAG_PMTU;
+		iph->frag_off = htons(IP_DF);
+	} else {
+		iph->frag_off = 0;
+	}
+
 	ip_send_check(iph);
 
 	IP_INC_STATS_BH(net, IPSTATS_MIB_REASMOKS);
@@ -633,16 +654,17 @@ out_fail:
 }
 
 /* Process an incoming IP datagram fragment. */
-int ip_defrag(struct sk_buff *skb, u32 user)
+int ip_defrag(struct net *net, struct sk_buff *skb, u32 user)
 {
+	struct net_device *dev = skb->dev ? : skb_dst(skb)->dev;
+	int vif = l3mdev_master_ifindex_rcu(dev);
 	struct ipq *qp;
-	struct net *net;
 
-	net = skb->dev ? dev_net(skb->dev) : dev_net(skb_dst(skb)->dev);
 	IP_INC_STATS_BH(net, IPSTATS_MIB_REASMREQDS);
+	skb_orphan(skb);
 
 	/* Lookup (or create) queue header */
-	qp = ip_find(net, ip_hdr(skb), user);
+	qp = ip_find(net, ip_hdr(skb), user, vif);
 	if (qp) {
 		int ret;
 
@@ -661,7 +683,7 @@ int ip_defrag(struct sk_buff *skb, u32 user)
 }
 EXPORT_SYMBOL(ip_defrag);
 
-struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user)
+struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
 {
 	struct iphdr iph;
 	int netoff;
@@ -690,7 +712,7 @@ struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user)
 			if (pskb_trim_rcsum(skb, netoff + len))
 				return skb;
 			memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
-			if (ip_defrag(skb, user))
+			if (ip_defrag(net, skb, user))
 				return NULL;
 			skb_clear_hash(skb);
 		}
@@ -818,6 +840,8 @@ static void __init ip4_frags_ctl_register(void)
 
 static int __net_init ipv4_frags_init_net(struct net *net)
 {
+	int res;
+
 	/* Fragment cache limits.
 	 *
 	 * The fragment memory accounting code, (tries to) account for
@@ -841,9 +865,13 @@ static int __net_init ipv4_frags_init_net(struct net *net)
 	 */
 	net->ipv4.frags.timeout = IP_FRAG_TIME;
 
-	inet_frags_init_net(&net->ipv4.frags);
-
-	return ip4_frags_ns_ctl_register(net);
+	res = inet_frags_init_net(&net->ipv4.frags);
+	if (res)
+		return res;
+	res = ip4_frags_ns_ctl_register(net);
+	if (res)
+		inet_frags_uninit_net(&net->ipv4.frags);
+	return res;
 }
 
 static void __net_exit ipv4_frags_exit_net(struct net *net)