Merge branch 'linux-3.4.35' into rel-17

Bug 1243631

Change-Id: I915826047b2e20f0ad0a7d75df295c6cbf6e5b0a

18 files changed, 342 insertions, 136 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 0b711659ac74..de5ec03036f1 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -240,8 +240,12 @@ EXPORT_SYMBOL(inet_listen);
 u32 inet_ehash_secret __read_mostly;
 EXPORT_SYMBOL(inet_ehash_secret);
 
+u32 ipv6_hash_secret __read_mostly;
+EXPORT_SYMBOL(ipv6_hash_secret);
+
 /*
- * inet_ehash_secret must be set exactly once
+ * inet_ehash_secret must be set exactly once, and to a non nul value
+ * ipv6_hash_secret must be set exactly once.
  */
 void build_ehash_secret(void)
 {
@@ -251,7 +255,8 @@ void build_ehash_secret(void)
 		get_random_bytes(&rnd, sizeof(rnd));
 	} while (rnd == 0);
 
-	cmpxchg(&inet_ehash_secret, 0, rnd);
+	if (cmpxchg(&inet_ehash_secret, 0, rnd) == 0)
+		get_random_bytes(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
 }
 EXPORT_SYMBOL(build_ehash_secret);
 
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 19d66cefd7d3..3f4043258542 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -659,6 +659,22 @@ void inet_csk_destroy_sock(struct sock *sk)
 }
 EXPORT_SYMBOL(inet_csk_destroy_sock);
 
+/* This function allows to force a closure of a socket after the call to
+ * tcp/dccp_create_openreq_child().
+ */
+void inet_csk_prepare_forced_close(struct sock *sk)
+{
+	/* sk_clone_lock locked the socket and set refcnt to 2 */
+	bh_unlock_sock(sk);
+	sock_put(sk);
+
+	/* The below has to be done to allow calling inet_csk_destroy_sock */
+	sock_set_flag(sk, SOCK_DEAD);
+	percpu_counter_inc(sk->sk_prot->orphan_count);
+	inet_sk(sk)->inet_num = 0;
+}
+EXPORT_SYMBOL(inet_csk_prepare_forced_close);
+
 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
 {
 	struct inet_sock *inet = inet_sk(sk);
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 8f8db724bfaf..d7b862ad4be4 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -44,6 +44,10 @@ struct inet_diag_entry {
 	u16 dport;
 	u16 family;
 	u16 userlocks;
+#if IS_ENABLED(CONFIG_IPV6)
+	struct in6_addr saddr_storage;	/* for IPv4-mapped-IPv6 addresses */
+	struct in6_addr daddr_storage;	/* for IPv4-mapped-IPv6 addresses */
+#endif
 };
 
 #define INET_DIAG_PUT(skb, attrtype, attrlen) \
@@ -419,25 +423,31 @@ static int inet_diag_bc_run(const struct nlattr *_bc,
 				break;
 			}
 
-			if (cond->prefix_len == 0)
-				break;
-
 			if (op->code == INET_DIAG_BC_S_COND)
 				addr = entry->saddr;
 			else
 				addr = entry->daddr;
 
+			if (cond->family != AF_UNSPEC &&
+			    cond->family != entry->family) {
+				if (entry->family == AF_INET6 &&
+				    cond->family == AF_INET) {
+					if (addr[0] == 0 && addr[1] == 0 &&
+					    addr[2] == htonl(0xffff) &&
+					    bitstring_match(addr + 3,
+							    cond->addr,
+							    cond->prefix_len))
+						break;
+				}
+				yes = 0;
+				break;
+			}
+
+			if (cond->prefix_len == 0)
+				break;
 			if (bitstring_match(addr, cond->addr,
 					    cond->prefix_len))
 				break;
-			if (entry->family == AF_INET6 &&
-			    cond->family == AF_INET) {
-				if (addr[0] == 0 && addr[1] == 0 &&
-				    addr[2] == htonl(0xffff) &&
-				    bitstring_match(addr + 3, cond->addr,
-						    cond->prefix_len))
-					break;
-			}
 			yes = 0;
 			break;
 		}
@@ -500,6 +510,55 @@ static int valid_cc(const void *bc, int len, int cc)
 	return 0;
 }
 
+/* Validate an inet_diag_hostcond. */
+static bool valid_hostcond(const struct inet_diag_bc_op *op, int len,
+			   int *min_len)
+{
+	int addr_len;
+	struct inet_diag_hostcond *cond;
+
+	/* Check hostcond space. */
+	*min_len += sizeof(struct inet_diag_hostcond);
+	if (len < *min_len)
+		return false;
+	cond = (struct inet_diag_hostcond *)(op + 1);
+
+	/* Check address family and address length. */
+	switch (cond->family) {
+	case AF_UNSPEC:
+		addr_len = 0;
+		break;
+	case AF_INET:
+		addr_len = sizeof(struct in_addr);
+		break;
+	case AF_INET6:
+		addr_len = sizeof(struct in6_addr);
+		break;
+	default:
+		return false;
+	}
+	*min_len += addr_len;
+	if (len < *min_len)
+		return false;
+
+	/* Check prefix length (in bits) vs address length (in bytes). */
+	if (cond->prefix_len > 8 * addr_len)
+		return false;
+
+	return true;
+}
+
+/* Validate a port comparison operator. */
+static inline bool valid_port_comparison(const struct inet_diag_bc_op *op,
+					 int len, int *min_len)
+{
+	/* Port comparisons put the port in a follow-on inet_diag_bc_op. */
+	*min_len += sizeof(struct inet_diag_bc_op);
+	if (len < *min_len)
+		return false;
+	return true;
+}
+
 static int inet_diag_bc_audit(const void *bytecode, int bytecode_len)
 {
 	const void *bc = bytecode;
@@ -507,29 +566,39 @@ static int inet_diag_bc_audit(const void *bytecode, int bytecode_len)
 
 	while (len > 0) {
 		const struct inet_diag_bc_op *op = bc;
+		int min_len = sizeof(struct inet_diag_bc_op);
 
 //printk("BC: %d %d %d {%d} / %d\n", op->code, op->yes, op->no, op[1].no, len);
 		switch (op->code) {
-		case INET_DIAG_BC_AUTO:
 		case INET_DIAG_BC_S_COND:
 		case INET_DIAG_BC_D_COND:
+			if (!valid_hostcond(bc, len, &min_len))
+				return -EINVAL;
+			break;
 		case INET_DIAG_BC_S_GE:
 		case INET_DIAG_BC_S_LE:
 		case INET_DIAG_BC_D_GE:
 		case INET_DIAG_BC_D_LE:
-		case INET_DIAG_BC_JMP:
-			if (op->no < 4 || op->no > len + 4 || op->no & 3)
-				return -EINVAL;
-			if (op->no < len &&
-			    !valid_cc(bytecode, bytecode_len, len - op->no))
+			if (!valid_port_comparison(bc, len, &min_len))
 				return -EINVAL;
 			break;
+		case INET_DIAG_BC_AUTO:
+		case INET_DIAG_BC_JMP:
 		case INET_DIAG_BC_NOP:
 			break;
 		default:
 			return -EINVAL;
 		}
-		if (op->yes < 4 || op->yes > len + 4 || op->yes & 3)
+
+		if (op->code != INET_DIAG_BC_NOP) {
+			if (op->no < min_len || op->no > len + 4 || op->no & 3)
+				return -EINVAL;
+			if (op->no < len &&
+			    !valid_cc(bytecode, bytecode_len, len - op->no))
+				return -EINVAL;
+		}
+
+		if (op->yes < min_len || op->yes > len + 4 || op->yes & 3)
 			return -EINVAL;
 		bc  += op->yes;
 		len -= op->yes;
@@ -586,6 +655,36 @@ static int inet_twsk_diag_dump(struct inet_timewait_sock *tw,
 				   cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
 }
 
+/* Get the IPv4, IPv6, or IPv4-mapped-IPv6 local and remote addresses
+ * from a request_sock. For IPv4-mapped-IPv6 we must map IPv4 to IPv6.
+ */
+static inline void inet_diag_req_addrs(const struct sock *sk,
+				       const struct request_sock *req,
+				       struct inet_diag_entry *entry)
+{
+	struct inet_request_sock *ireq = inet_rsk(req);
+
+#if IS_ENABLED(CONFIG_IPV6)
+	if (sk->sk_family == AF_INET6) {
+		if (req->rsk_ops->family == AF_INET6) {
+			entry->saddr = inet6_rsk(req)->loc_addr.s6_addr32;
+			entry->daddr = inet6_rsk(req)->rmt_addr.s6_addr32;
+		} else if (req->rsk_ops->family == AF_INET) {
+			ipv6_addr_set_v4mapped(ireq->loc_addr,
+					       &entry->saddr_storage);
+			ipv6_addr_set_v4mapped(ireq->rmt_addr,
+					       &entry->daddr_storage);
+			entry->saddr = entry->saddr_storage.s6_addr32;
+			entry->daddr = entry->daddr_storage.s6_addr32;
+		}
+	} else
+#endif
+	{
+		entry->saddr = &ireq->loc_addr;
+		entry->daddr = &ireq->rmt_addr;
+	}
+}
+
 static int inet_diag_fill_req(struct sk_buff *skb, struct sock *sk,
 			      struct request_sock *req, u32 pid, u32 seq,
 			      const struct nlmsghdr *unlh)
@@ -624,8 +723,10 @@ static int inet_diag_fill_req(struct sk_buff *skb, struct sock *sk,
 	r->idiag_inode = 0;
 #if IS_ENABLED(CONFIG_IPV6)
 	if (r->idiag_family == AF_INET6) {
-		*(struct in6_addr *)r->id.idiag_src = inet6_rsk(req)->loc_addr;
-		*(struct in6_addr *)r->id.idiag_dst = inet6_rsk(req)->rmt_addr;
+		struct inet_diag_entry entry;
+		inet_diag_req_addrs(sk, req, &entry);
+		memcpy(r->id.idiag_src, entry.saddr, sizeof(struct in6_addr));
+		memcpy(r->id.idiag_dst, entry.daddr, sizeof(struct in6_addr));
 	}
 #endif
 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
@@ -683,18 +784,7 @@ static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
 				continue;
 
 			if (bc) {
-				entry.saddr =
-#if IS_ENABLED(CONFIG_IPV6)
-					(entry.family == AF_INET6) ?
-					inet6_rsk(req)->loc_addr.s6_addr32 :
-#endif
-					&ireq->loc_addr;
-				entry.daddr =
-#if IS_ENABLED(CONFIG_IPV6)
-					(entry.family == AF_INET6) ?
-					inet6_rsk(req)->rmt_addr.s6_addr32 :
-#endif
-					&ireq->rmt_addr;
+				inet_diag_req_addrs(sk, req, &entry);
 				entry.dport = ntohs(ireq->rmt_port);
 
 				if (!inet_diag_bc_run(bc, &entry))
@@ -875,13 +965,16 @@ static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
 		struct inet_diag_req_v2 *r, struct nlattr *bc)
 {
 	const struct inet_diag_handler *handler;
+	int err = 0;
 
 	handler = inet_diag_lock_handler(r->sdiag_protocol);
 	if (!IS_ERR(handler))
 		handler->dump(skb, cb, r, bc);
+	else
+		err = PTR_ERR(handler);
 	inet_diag_unlock_handler(handler);
 
-	return skb->len;
+	return err ? : skb->len;
 }
 
 static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 3727e234c884..b7bf6e30adbc 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -685,28 +685,27 @@ EXPORT_SYMBOL(ip_defrag);
 
 struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user)
 {
-	const struct iphdr *iph;
+	struct iphdr iph;
 	u32 len;
 
 	if (skb->protocol != htons(ETH_P_IP))
 		return skb;
 
-	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+	if (!skb_copy_bits(skb, 0, &iph, sizeof(iph)))
 		return skb;
 
-	iph = ip_hdr(skb);
-	if (iph->ihl < 5 || iph->version != 4)
+	if (iph.ihl < 5 || iph.version != 4)
 		return skb;
-	if (!pskb_may_pull(skb, iph->ihl*4))
-		return skb;
-	iph = ip_hdr(skb);
-	len = ntohs(iph->tot_len);
-	if (skb->len < len || len < (iph->ihl * 4))
+
+	len = ntohs(iph.tot_len);
+	if (skb->len < len || len < (iph.ihl * 4))
 		return skb;
 
-	if (ip_is_fragment(ip_hdr(skb))) {
+	if (ip_is_fragment(&iph)) {
 		skb = skb_share_check(skb, GFP_ATOMIC);
 		if (skb) {
+			if (!pskb_may_pull(skb, iph.ihl*4))
+				return skb;
 			if (pskb_trim_rcsum(skb, len))
 				return skb;
 			memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 2fd0fba77124..374828487003 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -456,19 +456,28 @@ static int do_ip_setsockopt(struct sock *sk, int level,
 	struct inet_sock *inet = inet_sk(sk);
 	int val = 0, err;
 
-	if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
-			     (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
-			     (1<<IP_RETOPTS) | (1<<IP_TOS) |
-			     (1<<IP_TTL) | (1<<IP_HDRINCL) |
-			     (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
-			     (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
-			     (1<<IP_PASSSEC) | (1<<IP_TRANSPARENT) |
-			     (1<<IP_MINTTL) | (1<<IP_NODEFRAG))) ||
-	    optname == IP_UNICAST_IF ||
-	    optname == IP_MULTICAST_TTL ||
-	    optname == IP_MULTICAST_ALL ||
-	    optname == IP_MULTICAST_LOOP ||
-	    optname == IP_RECVORIGDSTADDR) {
+	switch (optname) {
+	case IP_PKTINFO:
+	case IP_RECVTTL:
+	case IP_RECVOPTS:
+	case IP_RECVTOS:
+	case IP_RETOPTS:
+	case IP_TOS:
+	case IP_TTL:
+	case IP_HDRINCL:
+	case IP_MTU_DISCOVER:
+	case IP_RECVERR:
+	case IP_ROUTER_ALERT:
+	case IP_FREEBIND:
+	case IP_PASSSEC:
+	case IP_TRANSPARENT:
+	case IP_MINTTL:
+	case IP_NODEFRAG:
+	case IP_UNICAST_IF:
+	case IP_MULTICAST_TTL:
+	case IP_MULTICAST_ALL:
+	case IP_MULTICAST_LOOP:
+	case IP_RECVORIGDSTADDR:
 		if (optlen >= sizeof(int)) {
 			if (get_user(val, (int __user *) optval))
 				return -EFAULT;
@@ -580,7 +589,7 @@ static int do_ip_setsockopt(struct sock *sk, int level,
 	case IP_TTL:
 		if (optlen < 1)
 			goto e_inval;
-		if (val != -1 && (val < 0 || val > 255))
+		if (val != -1 && (val < 1 || val > 255))
 			goto e_inval;
 		inet->uc_ttl = val;
 		break;
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 960fbfc3e976..8626b645ec62 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -124,6 +124,8 @@ static DEFINE_SPINLOCK(mfc_unres_lock);
 static struct kmem_cache *mrt_cachep __read_mostly;
 
 static struct mr_table *ipmr_new_table(struct net *net, u32 id);
+static void ipmr_free_table(struct mr_table *mrt);
+
 static int ip_mr_forward(struct net *net, struct mr_table *mrt,
 			 struct sk_buff *skb, struct mfc_cache *cache,
 			 int local);
@@ -131,6 +133,7 @@ static int ipmr_cache_report(struct mr_table *mrt,
 			     struct sk_buff *pkt, vifi_t vifi, int assert);
 static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
 			      struct mfc_cache *c, struct rtmsg *rtm);
+static void mroute_clean_tables(struct mr_table *mrt);
 static void ipmr_expire_process(unsigned long arg);
 
 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
@@ -271,7 +274,7 @@ static void __net_exit ipmr_rules_exit(struct net *net)
 
 	list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
 		list_del(&mrt->list);
-		kfree(mrt);
+		ipmr_free_table(mrt);
 	}
 	fib_rules_unregister(net->ipv4.mr_rules_ops);
 }
@@ -299,7 +302,7 @@ static int __net_init ipmr_rules_init(struct net *net)
 
 static void __net_exit ipmr_rules_exit(struct net *net)
 {
-	kfree(net->ipv4.mrt);
+	ipmr_free_table(net->ipv4.mrt);
 }
 #endif
 
@@ -336,6 +339,13 @@ static struct mr_table *ipmr_new_table(struct net *net, u32 id)
 	return mrt;
 }
 
+static void ipmr_free_table(struct mr_table *mrt)
+{
+	del_timer_sync(&mrt->ipmr_expire_timer);
+	mroute_clean_tables(mrt);
+	kfree(mrt);
+}
+
 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
 
 static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
diff --git a/net/ipv4/netfilter/nf_nat_sip.c b/net/ipv4/netfilter/nf_nat_sip.c
index 57932c43960e..566be2dd73f4 100644
--- a/net/ipv4/netfilter/nf_nat_sip.c
+++ b/net/ipv4/netfilter/nf_nat_sip.c
@@ -148,7 +148,7 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff,
 	if (ct_sip_parse_header_uri(ct, *dptr, NULL, *datalen,
 				    hdr, NULL, &matchoff, &matchlen,
 				    &addr, &port) > 0) {
-		unsigned int matchend, poff, plen, buflen, n;
+		unsigned int olen, matchend, poff, plen, buflen, n;
 		char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")];
 
 		/* We're only interested in headers related to this
@@ -163,11 +163,12 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff,
 				goto next;
 		}
 
+		olen = *datalen;
 		if (!map_addr(skb, dataoff, dptr, datalen, matchoff, matchlen,
 			      &addr, port))
 			return NF_DROP;
 
-		matchend = matchoff + matchlen;
+		matchend = matchoff + matchlen + *datalen - olen;
 
 		/* The maddr= parameter (RFC 2361) specifies where to send
 		 * the reply. */
@@ -501,7 +502,10 @@ static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int dataoff,
 		ret = nf_ct_expect_related(rtcp_exp);
 		if (ret == 0)
 			break;
-		else if (ret != -EBUSY) {
+		else if (ret == -EBUSY) {
+			nf_ct_unexpect_related(rtp_exp);
+			continue;
+		} else if (ret < 0) {
 			nf_ct_unexpect_related(rtp_exp);
 			port = 0;
 			break;
diff --git a/net/ipv4/netfilter/nf_nat_standalone.c b/net/ipv4/netfilter/nf_nat_standalone.c
index 3828a4229822..da4098f08784 100644
--- a/net/ipv4/netfilter/nf_nat_standalone.c
+++ b/net/ipv4/netfilter/nf_nat_standalone.c
@@ -194,7 +194,8 @@ nf_nat_out(unsigned int hooknum,
 
 		if ((ct->tuplehash[dir].tuple.src.u3.ip !=
 		     ct->tuplehash[!dir].tuple.dst.u3.ip) ||
-		    (ct->tuplehash[dir].tuple.src.u.all !=
+		    (ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP &&
+		     ct->tuplehash[dir].tuple.src.u.all !=
 		     ct->tuplehash[!dir].tuple.dst.u.all)
 		   )
 			return ip_xfrm_me_harder(skb) == 0 ? ret : NF_DROP;
@@ -230,7 +231,8 @@ nf_nat_local_fn(unsigned int hooknum,
 				ret = NF_DROP;
 		}
 #ifdef CONFIG_XFRM
-		else if (ct->tuplehash[dir].tuple.dst.u.all !=
+		else if (ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP &&
+			 ct->tuplehash[dir].tuple.dst.u.all !=
 			 ct->tuplehash[!dir].tuple.src.u.all)
 			if (ip_xfrm_me_harder(skb))
 				ret = NF_DROP;
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 50009c787bcd..c234bda5b801 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -321,8 +321,8 @@ void ping_err(struct sk_buff *skb, u32 info)
 	struct iphdr *iph = (struct iphdr *)skb->data;
 	struct icmphdr *icmph = (struct icmphdr *)(skb->data+(iph->ihl<<2));
 	struct inet_sock *inet_sock;
-	int type = icmph->type;
-	int code = icmph->code;
+	int type = icmp_hdr(skb)->type;
+	int code = icmp_hdr(skb)->code;
 	struct net *net = dev_net(skb->dev);
 	struct sock *sk;
 	int harderr;
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 8af0d44e4e22..212897517b89 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -232,7 +232,6 @@ static const struct snmp_mib snmp4_net_list[] = {
 	SNMP_MIB_ITEM("TCPDSACKOfoSent", LINUX_MIB_TCPDSACKOFOSENT),
 	SNMP_MIB_ITEM("TCPDSACKRecv", LINUX_MIB_TCPDSACKRECV),
 	SNMP_MIB_ITEM("TCPDSACKOfoRecv", LINUX_MIB_TCPDSACKOFORECV),
-	SNMP_MIB_ITEM("TCPAbortOnSyn", LINUX_MIB_TCPABORTONSYN),
 	SNMP_MIB_ITEM("TCPAbortOnData", LINUX_MIB_TCPABORTONDATA),
 	SNMP_MIB_ITEM("TCPAbortOnClose", LINUX_MIB_TCPABORTONCLOSE),
 	SNMP_MIB_ITEM("TCPAbortOnMemory", LINUX_MIB_TCPABORTONMEMORY),
@@ -258,6 +257,8 @@ static const struct snmp_mib snmp4_net_list[] = {
 	SNMP_MIB_ITEM("TCPReqQFullDrop", LINUX_MIB_TCPREQQFULLDROP),
 	SNMP_MIB_ITEM("TCPRetransFail", LINUX_MIB_TCPRETRANSFAIL),
 	SNMP_MIB_ITEM("TCPRcvCoalesce", LINUX_MIB_TCPRCVCOALESCE),
+	SNMP_MIB_ITEM("TCPChallengeACK", LINUX_MIB_TCPCHALLENGEACK),
+	SNMP_MIB_ITEM("TCPSYNChallenge", LINUX_MIB_TCPSYNCHALLENGE),
 	SNMP_MIB_SENTINEL
 };
 
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index bbd604c68e68..2fe0dc28ea98 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -131,18 +131,20 @@ found:
  *	0 - deliver
  *	1 - block
  */
-static __inline__ int icmp_filter(struct sock *sk, struct sk_buff *skb)
+static int icmp_filter(const struct sock *sk, const struct sk_buff *skb)
 {
-	int type;
+	struct icmphdr _hdr;
+	const struct icmphdr *hdr;
 
-	if (!pskb_may_pull(skb, sizeof(struct icmphdr)))
+	hdr = skb_header_pointer(skb, skb_transport_offset(skb),
+				 sizeof(_hdr), &_hdr);
+	if (!hdr)
 		return 1;
 
-	type = icmp_hdr(skb)->type;
-	if (type < 32) {
+	if (hdr->type < 32) {
 		__u32 data = raw_sk(sk)->filter.data;
 
-		return ((1 << type) & data) != 0;
+		return ((1U << hdr->type) & data) != 0;
 	}
 
 	/* Do not block unknown ICMP types */
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 7a7724da9bff..bf7a604c695c 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -590,6 +590,13 @@ static struct ctl_table ipv4_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
 	},
+	{
+		.procname	= "tcp_challenge_ack_limit",
+		.data		= &sysctl_tcp_challenge_ack_limit,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
 #ifdef CONFIG_NET_DMA
 	{
 		.procname	= "tcp_dma_copybreak",
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 38d6e4374561..8429ac5eb914 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -485,14 +485,12 @@ int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
 			 !tp->urg_data ||
 			 before(tp->urg_seq, tp->copied_seq) ||
 			 !before(tp->urg_seq, tp->rcv_nxt)) {
-			struct sk_buff *skb;
 
 			answ = tp->rcv_nxt - tp->copied_seq;
 
-			/* Subtract 1, if FIN is in queue. */
-			skb = skb_peek_tail(&sk->sk_receive_queue);
-			if (answ && skb)
-				answ -= tcp_hdr(skb)->fin;
+			/* Subtract 1, if FIN was received */
+			if (answ && sock_flag(sk, SOCK_DONE))
+				answ--;
 		} else
 			answ = tp->urg_seq - tp->copied_seq;
 		release_sock(sk);
@@ -744,7 +742,9 @@ static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now,
 			   old_size_goal + mss_now > xmit_size_goal)) {
 			xmit_size_goal = old_size_goal;
 		} else {
-			tp->xmit_size_goal_segs = xmit_size_goal / mss_now;
+			tp->xmit_size_goal_segs =
+				min_t(u16, xmit_size_goal / mss_now,
+				      sk->sk_gso_max_segs);
 			xmit_size_goal = tp->xmit_size_goal_segs * mss_now;
 		}
 	}
@@ -1602,8 +1602,14 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		}
 
 #ifdef CONFIG_NET_DMA
-		if (tp->ucopy.dma_chan)
-			dma_async_memcpy_issue_pending(tp->ucopy.dma_chan);
+		if (tp->ucopy.dma_chan) {
+			if (tp->rcv_wnd == 0 &&
+			    !skb_queue_empty(&sk->sk_async_wait_queue)) {
+				tcp_service_net_dma(sk, true);
+				tcp_cleanup_rbuf(sk, copied);
+			} else
+				dma_async_memcpy_issue_pending(tp->ucopy.dma_chan);
+		}
 #endif
 		if (copied >= target) {
 			/* Do not sleep, just process backlog. */
diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
index 272a84593c85..69251dde7501 100644
--- a/net/ipv4/tcp_cong.c
+++ b/net/ipv4/tcp_cong.c
@@ -291,7 +291,8 @@ int tcp_is_cwnd_limited(const struct sock *sk, u32 in_flight)
 	left = tp->snd_cwnd - in_flight;
 	if (sk_can_gso(sk) &&
 	    left * sysctl_tcp_tso_win_divisor < tp->snd_cwnd &&
-	    left * tp->mss_cache < sk->sk_gso_max_size)
+	    left * tp->mss_cache < sk->sk_gso_max_size &&
+	    left < sk->sk_gso_max_segs)
 		return 1;
 	return left <= tcp_max_tso_deferred_mss(tp);
 }
diff --git a/net/ipv4/tcp_illinois.c b/net/ipv4/tcp_illinois.c
index 813b43a76fec..834857f3c871 100644
--- a/net/ipv4/tcp_illinois.c
+++ b/net/ipv4/tcp_illinois.c
@@ -313,11 +313,13 @@ static void tcp_illinois_info(struct sock *sk, u32 ext,
 			.tcpv_rttcnt = ca->cnt_rtt,
 			.tcpv_minrtt = ca->base_rtt,
 		};
-		u64 t = ca->sum_rtt;
 
-		do_div(t, ca->cnt_rtt);
-		info.tcpv_rtt = t;
+		if (info.tcpv_rttcnt > 0) {
+			u64 t = ca->sum_rtt;
 
+			do_div(t, info.tcpv_rttcnt);
+			info.tcpv_rtt = t;
+		}
 		nla_put(skb, INET_DIAG_VEGASINFO, sizeof(info), &info);
 	}
 }
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 6b017383119e..b40e05b9c451 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -88,6 +88,9 @@ int sysctl_tcp_app_win __read_mostly = 31;
 int sysctl_tcp_adv_win_scale __read_mostly = 1;
 EXPORT_SYMBOL(sysctl_tcp_adv_win_scale);
 
+/* rfc5961 challenge ack rate limiting */
+int sysctl_tcp_challenge_ack_limit = 100;
+
 int sysctl_tcp_stdurg __read_mostly;
 int sysctl_tcp_rfc1337 __read_mostly;
 int sysctl_tcp_max_orphans __read_mostly = NR_FILE;
@@ -3037,13 +3040,14 @@ static void tcp_update_cwnd_in_recovery(struct sock *sk, int newly_acked_sacked,
  * tcp_xmit_retransmit_queue().
  */
 static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked,
-				  int newly_acked_sacked, bool is_dupack,
+				  int prior_sacked, bool is_dupack,
 				  int flag)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	int do_lost = is_dupack || ((flag & FLAG_DATA_SACKED) &&
 				    (tcp_fackets_out(tp) > tp->reordering));
+	int newly_acked_sacked = 0;
 	int fast_rexmit = 0, mib_idx;
 
 	if (WARN_ON(!tp->packets_out && tp->sacked_out))
@@ -3103,6 +3107,7 @@ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked,
 				tcp_add_reno_sack(sk);
 		} else
 			do_lost = tcp_try_undo_partial(sk, pkts_acked);
+		newly_acked_sacked = pkts_acked + tp->sacked_out - prior_sacked;
 		break;
 	case TCP_CA_Loss:
 		if (flag & FLAG_DATA_ACKED)
@@ -3124,6 +3129,7 @@ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked,
 			if (is_dupack)
 				tcp_add_reno_sack(sk);
 		}
+		newly_acked_sacked = pkts_acked + tp->sacked_out - prior_sacked;
 
 		if (icsk->icsk_ca_state <= TCP_CA_Disorder)
 			tcp_try_undo_dsack(sk);
@@ -3633,6 +3639,11 @@ static int tcp_process_frto(struct sock *sk, int flag)
 		}
 	} else {
 		if (!(flag & FLAG_DATA_ACKED) && (tp->frto_counter == 1)) {
+			if (!tcp_packets_in_flight(tp)) {
+				tcp_enter_frto_loss(sk, 2, flag);
+				return true;
+			}
+
 			/* Prevent sending of new data. */
 			tp->snd_cwnd = min(tp->snd_cwnd,
 					   tcp_packets_in_flight(tp));
@@ -3681,6 +3692,24 @@ static int tcp_process_frto(struct sock *sk, int flag)
 	return 0;
 }
 
+/* RFC 5961 7 [ACK Throttling] */
+static void tcp_send_challenge_ack(struct sock *sk)
+{
+	/* unprotected vars, we dont care of overwrites */
+	static u32 challenge_timestamp;
+	static unsigned int challenge_count;
+	u32 now = jiffies / HZ;
+
+	if (now != challenge_timestamp) {
+		challenge_timestamp = now;
+		challenge_count = 0;
+	}
+	if (++challenge_count <= sysctl_tcp_challenge_ack_limit) {
+		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPCHALLENGEACK);
+		tcp_send_ack(sk);
+	}
+}
+
 /* This routine deals with incoming acks, but not outgoing ones. */
 static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 {
@@ -3695,14 +3724,19 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	int prior_packets;
 	int prior_sacked = tp->sacked_out;
 	int pkts_acked = 0;
-	int newly_acked_sacked = 0;
 	int frto_cwnd = 0;
 
 	/* If the ack is older than previous acks
 	 * then we can probably ignore it.
 	 */
-	if (before(ack, prior_snd_una))
+	if (before(ack, prior_snd_una)) {
+		/* RFC 5961 5.2 [Blind Data Injection Attack].[Mitigation] */
+		if (before(ack, prior_snd_una - tp->max_window)) {
+			tcp_send_challenge_ack(sk);
+			return -1;
+		}
 		goto old_ack;
+	}
 
 	/* If the ack includes data we haven't sent yet, discard
 	 * this segment (RFC793 Section 3.9).
@@ -3768,8 +3802,6 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	flag |= tcp_clean_rtx_queue(sk, prior_fackets, prior_snd_una);
 
 	pkts_acked = prior_packets - tp->packets_out;
-	newly_acked_sacked = (prior_packets - prior_sacked) -
-			     (tp->packets_out - tp->sacked_out);
 
 	if (tp->frto_counter)
 		frto_cwnd = tcp_process_frto(sk, flag);
@@ -3783,7 +3815,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 		    tcp_may_raise_cwnd(sk, flag))
 			tcp_cong_avoid(sk, ack, prior_in_flight);
 		is_dupack = !(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP));
-		tcp_fastretrans_alert(sk, pkts_acked, newly_acked_sacked,
+		tcp_fastretrans_alert(sk, pkts_acked, prior_sacked,
 				      is_dupack, flag);
 	} else {
 		if ((flag & FLAG_DATA_ACKED) && !frto_cwnd)
@@ -3798,7 +3830,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 no_queue:
 	/* If data was DSACKed, see if we can undo a cwnd reduction. */
 	if (flag & FLAG_DSACKING_ACK)
-		tcp_fastretrans_alert(sk, pkts_acked, newly_acked_sacked,
+		tcp_fastretrans_alert(sk, pkts_acked, prior_sacked,
 				      is_dupack, flag);
 	/* If this ack opens up a zero window, clear backoff.  It was
 	 * being used to time the probes, and is probably far higher than
@@ -3818,8 +3850,7 @@ old_ack:
 	 */
 	if (TCP_SKB_CB(skb)->sacked) {
 		flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una);
-		newly_acked_sacked = tp->sacked_out - prior_sacked;
-		tcp_fastretrans_alert(sk, pkts_acked, newly_acked_sacked,
+		tcp_fastretrans_alert(sk, pkts_acked, prior_sacked,
 				      is_dupack, flag);
 	}
 
@@ -5271,8 +5302,8 @@ out:
 /* Does PAWS and seqno based validation of an incoming segment, flags will
  * play significant role here.
  */
-static int tcp_validate_incoming(struct sock *sk, struct sk_buff *skb,
-			      const struct tcphdr *th, int syn_inerr)
+static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb,
+				  const struct tcphdr *th, int syn_inerr)
 {
 	const u8 *hash_location;
 	struct tcp_sock *tp = tcp_sk(sk);
@@ -5297,38 +5328,48 @@ static int tcp_validate_incoming(struct sock *sk, struct sk_buff *skb,
 		 * an acknowledgment should be sent in reply (unless the RST
 		 * bit is set, if so drop the segment and return)".
 		 */
-		if (!th->rst)
+		if (!th->rst) {
+			if (th->syn)
+				goto syn_challenge;
 			tcp_send_dupack(sk, skb);
+		}
 		goto discard;
 	}
 
 	/* Step 2: check RST bit */
 	if (th->rst) {
-		tcp_reset(sk);
+		/* RFC 5961 3.2 :
+		 * If sequence number exactly matches RCV.NXT, then
+		 *     RESET the connection
+		 * else
+		 *     Send a challenge ACK
+		 */
+		if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt)
+			tcp_reset(sk);
+		else
+			tcp_send_challenge_ack(sk);
 		goto discard;
 	}
 
-	/* ts_recent update must be made after we are sure that the packet
-	 * is in window.
-	 */
-	tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
-
 	/* step 3: check security and precedence [ignored] */
 
-	/* step 4: Check for a SYN in window. */
-	if (th->syn && !before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) {
+	/* step 4: Check for a SYN
+	 * RFC 5691 4.2 : Send a challenge ack
+	 */
+	if (th->syn) {
+syn_challenge:
 		if (syn_inerr)
 			TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS);
-		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPABORTONSYN);
-		tcp_reset(sk);
-		return -1;
+		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPSYNCHALLENGE);
+		tcp_send_challenge_ack(sk);
+		goto discard;
 	}
 
-	return 1;
+	return true;
 
 discard:
 	__kfree_skb(skb);
-	return 0;
+	return false;
 }
 
 /*
@@ -5358,7 +5399,6 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
 			const struct tcphdr *th, unsigned int len)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
-	int res;
 
 	/*
 	 *	Header prediction.
@@ -5538,14 +5578,18 @@ slow_path:
 	 *	Standard slow path.
 	 */
 
-	res = tcp_validate_incoming(sk, skb, th, 1);
-	if (res <= 0)
-		return -res;
+	if (!tcp_validate_incoming(sk, skb, th, 1))
+		return 0;
 
 step5:
 	if (th->ack && tcp_ack(sk, skb, FLAG_SLOWPATH) < 0)
 		goto discard;
 
+	/* ts_recent update must be made after we are sure that the packet
+	 * is in window.
+	 */
+	tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
+
 	tcp_rcv_rtt_measure_ts(sk, skb);
 
 	/* Process urgent data. */
@@ -5850,7 +5894,6 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	int queued = 0;
-	int res;
 
 	tp->rx_opt.saw_tstamp = 0;
 
@@ -5905,9 +5948,8 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 		return 0;
 	}
 
-	res = tcp_validate_incoming(sk, skb, th, 0);
-	if (res <= 0)
-		return -res;
+	if (!tcp_validate_incoming(sk, skb, th, 0))
+		return 0;
 
 	/* step 5: check the ACK field */
 	if (th->ack) {
@@ -6018,6 +6060,11 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 	} else
 		goto discard;
 
+	/* ts_recent update must be made after we are sure that the packet
+	 * is in window.
+	 */
+	tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
+
 	/* step 6: check the URG bit */
 	tcp_urg(sk, skb, th);
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 0cb86ceb652f..76f50e1b53af 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -678,10 +678,11 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
 	arg.csumoffset = offsetof(struct tcphdr, check) / 2;
 	arg.flags = (sk && inet_sk(sk)->transparent) ? IP_REPLY_ARG_NOSRCCHECK : 0;
 	/* When socket is gone, all binding information is lost.
-	 * routing might fail in this case. using iif for oif to
-	 * make sure we can deliver it
+	 * routing might fail in this case. No choice here, if we choose to force
+	 * input interface, we will misroute in case of asymmetric route.
 	 */
-	arg.bound_dev_if = sk ? sk->sk_bound_dev_if : inet_iif(skb);
+	if (sk)
+		arg.bound_dev_if = sk->sk_bound_dev_if;
 
 	net = dev_net(skb_dst(skb)->dev);
 	arg.tos = ip_hdr(skb)->tos;
@@ -1523,10 +1524,8 @@ exit:
 	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
 	return NULL;
 put_and_exit:
-	tcp_clear_xmit_timers(newsk);
-	tcp_cleanup_congestion_control(newsk);
-	bh_unlock_sock(newsk);
-	sock_put(newsk);
+	inet_csk_prepare_forced_close(newsk);
+	tcp_done(newsk);
 	goto exit;
 }
 EXPORT_SYMBOL(tcp_v4_syn_recv_sock);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 7ac6423117ad..2d27e1af9303 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1318,21 +1318,21 @@ static void tcp_cwnd_validate(struct sock *sk)
  * when we would be allowed to send the split-due-to-Nagle skb fully.
  */
 static unsigned int tcp_mss_split_point(const struct sock *sk, const struct sk_buff *skb,
-					unsigned int mss_now, unsigned int cwnd)
+					unsigned int mss_now, unsigned int max_segs)
 {
 	const struct tcp_sock *tp = tcp_sk(sk);
-	u32 needed, window, cwnd_len;
+	u32 needed, window, max_len;
 
 	window = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
-	cwnd_len = mss_now * cwnd;
+	max_len = mss_now * max_segs;
 
-	if (likely(cwnd_len <= window && skb != tcp_write_queue_tail(sk)))
-		return cwnd_len;
+	if (likely(max_len <= window && skb != tcp_write_queue_tail(sk)))
+		return max_len;
 
 	needed = min(skb->len, window);
 
-	if (cwnd_len <= needed)
-		return cwnd_len;
+	if (max_len <= needed)
+		return max_len;
 
 	return needed - needed % mss_now;
 }
@@ -1560,7 +1560,8 @@ static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
 	limit = min(send_win, cong_win);
 
 	/* If a full-sized TSO skb can be sent, do it. */
-	if (limit >= sk->sk_gso_max_size)
+	if (limit >= min_t(unsigned int, sk->sk_gso_max_size,
+			   sk->sk_gso_max_segs * tp->mss_cache))
 		goto send_now;
 
 	/* Middle in queue won't get any more data, full sendable already? */
@@ -1786,7 +1787,9 @@ static int tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
 		limit = mss_now;
 		if (tso_segs > 1 && !tcp_urg_mode(tp))
 			limit = tcp_mss_split_point(sk, skb, mss_now,
-						    cwnd_quota);
+						    min_t(unsigned int,
+							  cwnd_quota,
+							  sk->sk_gso_max_segs));
 
 		if (skb->len > limit &&
 		    unlikely(tso_fragment(sk, skb, limit, mss_now, gfp)))