Linux-libre 4.8.2-gnupck-4.8.2-gnu

1 files changed, 276 insertions, 114 deletions

diff --git a/net/sctp/output.c b/net/sctp/output.c
index 9844fe573..31b7bc358 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -84,18 +84,42 @@ static void sctp_packet_reset(struct sctp_packet *packet)
 struct sctp_packet *sctp_packet_config(struct sctp_packet *packet,
 				       __u32 vtag, int ecn_capable)
 {
-	struct sctp_chunk *chunk = NULL;
+	struct sctp_transport *tp = packet->transport;
+	struct sctp_association *asoc = tp->asoc;
 
 	pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag);
 
 	packet->vtag = vtag;
 
+	if (asoc && tp->dst) {
+		struct sock *sk = asoc->base.sk;
+
+		rcu_read_lock();
+		if (__sk_dst_get(sk) != tp->dst) {
+			dst_hold(tp->dst);
+			sk_setup_caps(sk, tp->dst);
+		}
+
+		if (sk_can_gso(sk)) {
+			struct net_device *dev = tp->dst->dev;
+
+			packet->max_size = dev->gso_max_size;
+		} else {
+			packet->max_size = asoc->pathmtu;
+		}
+		rcu_read_unlock();
+
+	} else {
+		packet->max_size = tp->pathmtu;
+	}
+
 	if (ecn_capable && sctp_packet_empty(packet)) {
-		chunk = sctp_get_ecne_prepend(packet->transport->asoc);
+		struct sctp_chunk *chunk;
 
 		/* If there a is a prepend chunk stick it on the list before
 		 * any other chunks get appended.
 		 */
+		chunk = sctp_get_ecne_prepend(asoc);
 		if (chunk)
 			sctp_packet_append_chunk(packet, chunk);
 	}
@@ -158,7 +182,8 @@ sctp_xmit_t sctp_packet_transmit_chunk(struct sctp_packet *packet,
 	sctp_xmit_t retval;
 	int error = 0;
 
-	pr_debug("%s: packet:%p chunk:%p\n", __func__, packet, chunk);
+	pr_debug("%s: packet:%p size:%Zu chunk:%p size:%d\n", __func__,
+		 packet, packet->size, chunk, chunk->skb ? chunk->skb->len : -1);
 
 	switch ((retval = (sctp_packet_append_chunk(packet, chunk)))) {
 	case SCTP_XMIT_PMTU_FULL:
@@ -291,6 +316,8 @@ static sctp_xmit_t __sctp_packet_append_chunk(struct sctp_packet *packet,
 		packet->has_data = 1;
 		/* timestamp the chunk for rtx purposes */
 		chunk->sent_at = jiffies;
+		/* Mainly used for prsctp RTX policy */
+		chunk->sent_count++;
 		break;
 	case SCTP_CID_COOKIE_ECHO:
 		packet->has_cookie_echo = 1;
@@ -381,12 +408,15 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 	struct sctp_transport *tp = packet->transport;
 	struct sctp_association *asoc = tp->asoc;
 	struct sctphdr *sh;
-	struct sk_buff *nskb;
+	struct sk_buff *nskb = NULL, *head = NULL;
 	struct sctp_chunk *chunk, *tmp;
 	struct sock *sk;
 	int err = 0;
 	int padding;		/* How much padding do we need?  */
+	int pkt_size;
 	__u8 has_data = 0;
+	int gso = 0;
+	int pktcount = 0;
 	struct dst_entry *dst;
 	unsigned char *auth = NULL;	/* pointer to auth in skb data */
 
@@ -400,18 +430,37 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 	chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
 	sk = chunk->skb->sk;
 
-	/* Allocate the new skb.  */
-	nskb = alloc_skb(packet->size + MAX_HEADER, gfp);
-	if (!nskb)
+	/* Allocate the head skb, or main one if not in GSO */
+	if (packet->size > tp->pathmtu && !packet->ipfragok) {
+		if (sk_can_gso(sk)) {
+			gso = 1;
+			pkt_size = packet->overhead;
+		} else {
+			/* If this happens, we trash this packet and try
+			 * to build a new one, hopefully correct this
+			 * time. Application may notice this error.
+			 */
+			pr_err_once("Trying to GSO but underlying device doesn't support it.");
+			goto nomem;
+		}
+	} else {
+		pkt_size = packet->size;
+	}
+	head = alloc_skb(pkt_size + MAX_HEADER, gfp);
+	if (!head)
 		goto nomem;
+	if (gso) {
+		NAPI_GRO_CB(head)->last = head;
+		skb_shinfo(head)->gso_type = sk->sk_gso_type;
+	}
 
 	/* Make sure the outbound skb has enough header room reserved. */
-	skb_reserve(nskb, packet->overhead + MAX_HEADER);
+	skb_reserve(head, packet->overhead + MAX_HEADER);
 
 	/* Set the owning socket so that we know where to get the
 	 * destination IP address.
 	 */
-	sctp_packet_set_owner_w(nskb, sk);
+	sctp_packet_set_owner_w(head, sk);
 
 	if (!sctp_transport_dst_check(tp)) {
 		sctp_transport_route(tp, NULL, sctp_sk(sk));
@@ -422,11 +471,11 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 	dst = dst_clone(tp->dst);
 	if (!dst)
 		goto no_route;
-	skb_dst_set(nskb, dst);
+	skb_dst_set(head, dst);
 
 	/* Build the SCTP header.  */
-	sh = (struct sctphdr *)skb_push(nskb, sizeof(struct sctphdr));
-	skb_reset_transport_header(nskb);
+	sh = (struct sctphdr *)skb_push(head, sizeof(struct sctphdr));
+	skb_reset_transport_header(head);
 	sh->source = htons(packet->source_port);
 	sh->dest   = htons(packet->destination_port);
 
@@ -441,90 +490,144 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 	sh->vtag     = htonl(packet->vtag);
 	sh->checksum = 0;
 
-	/**
-	 * 6.10 Bundling
-	 *
-	 *    An endpoint bundles chunks by simply including multiple
-	 *    chunks in one outbound SCTP packet.  ...
-	 */
-
-	/**
-	 * 3.2  Chunk Field Descriptions
-	 *
-	 * The total length of a chunk (including Type, Length and
-	 * Value fields) MUST be a multiple of 4 bytes.  If the length
-	 * of the chunk is not a multiple of 4 bytes, the sender MUST
-	 * pad the chunk with all zero bytes and this padding is not
-	 * included in the chunk length field.  The sender should
-	 * never pad with more than 3 bytes.
-	 *
-	 * [This whole comment explains WORD_ROUND() below.]
-	 */
-
 	pr_debug("***sctp_transmit_packet***\n");
 
-	list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
-		list_del_init(&chunk->list);
-		if (sctp_chunk_is_data(chunk)) {
-			/* 6.3.1 C4) When data is in flight and when allowed
-			 * by rule C5, a new RTT measurement MUST be made each
-			 * round trip.  Furthermore, new RTT measurements
-			 * SHOULD be made no more than once per round-trip
-			 * for a given destination transport address.
-			 */
+	do {
+		/* Set up convenience variables... */
+		chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
+		pktcount++;
 
-			if (!chunk->resent && !tp->rto_pending) {
-				chunk->rtt_in_progress = 1;
-				tp->rto_pending = 1;
+		/* Calculate packet size, so it fits in PMTU. Leave
+		 * other chunks for the next packets.
+		 */
+		if (gso) {
+			pkt_size = packet->overhead;
+			list_for_each_entry(chunk, &packet->chunk_list, list) {
+				int padded = WORD_ROUND(chunk->skb->len);
+
+				if (pkt_size + padded > tp->pathmtu)
+					break;
+				pkt_size += padded;
 			}
 
-			has_data = 1;
-		}
+			/* Allocate a new skb. */
+			nskb = alloc_skb(pkt_size + MAX_HEADER, gfp);
+			if (!nskb)
+				goto nomem;
 
-		padding = WORD_ROUND(chunk->skb->len) - chunk->skb->len;
-		if (padding)
-			memset(skb_put(chunk->skb, padding), 0, padding);
+			/* Make sure the outbound skb has enough header
+			 * room reserved.
+			 */
+			skb_reserve(nskb, packet->overhead + MAX_HEADER);
+		} else {
+			nskb = head;
+		}
 
-		/* if this is the auth chunk that we are adding,
-		 * store pointer where it will be added and put
-		 * the auth into the packet.
+		/**
+		 * 3.2  Chunk Field Descriptions
+		 *
+		 * The total length of a chunk (including Type, Length and
+		 * Value fields) MUST be a multiple of 4 bytes.  If the length
+		 * of the chunk is not a multiple of 4 bytes, the sender MUST
+		 * pad the chunk with all zero bytes and this padding is not
+		 * included in the chunk length field.  The sender should
+		 * never pad with more than 3 bytes.
+		 *
+		 * [This whole comment explains WORD_ROUND() below.]
 		 */
-		if (chunk == packet->auth)
-			auth = skb_tail_pointer(nskb);
 
-		memcpy(skb_put(nskb, chunk->skb->len),
+		pkt_size -= packet->overhead;
+		list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
+			list_del_init(&chunk->list);
+			if (sctp_chunk_is_data(chunk)) {
+				/* 6.3.1 C4) When data is in flight and when allowed
+				 * by rule C5, a new RTT measurement MUST be made each
+				 * round trip.  Furthermore, new RTT measurements
+				 * SHOULD be made no more than once per round-trip
+				 * for a given destination transport address.
+				 */
+
+				if (!chunk->resent && !tp->rto_pending) {
+					chunk->rtt_in_progress = 1;
+					tp->rto_pending = 1;
+				}
+
+				has_data = 1;
+			}
+
+			padding = WORD_ROUND(chunk->skb->len) - chunk->skb->len;
+			if (padding)
+				memset(skb_put(chunk->skb, padding), 0, padding);
+
+			/* if this is the auth chunk that we are adding,
+			 * store pointer where it will be added and put
+			 * the auth into the packet.
+			 */
+			if (chunk == packet->auth)
+				auth = skb_tail_pointer(nskb);
+
+			memcpy(skb_put(nskb, chunk->skb->len),
 			       chunk->skb->data, chunk->skb->len);
 
-		pr_debug("*** Chunk:%p[%s] %s 0x%x, length:%d, chunk->skb->len:%d, "
-			 "rtt_in_progress:%d\n", chunk,
-			 sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
-			 chunk->has_tsn ? "TSN" : "No TSN",
-			 chunk->has_tsn ? ntohl(chunk->subh.data_hdr->tsn) : 0,
-			 ntohs(chunk->chunk_hdr->length), chunk->skb->len,
-			 chunk->rtt_in_progress);
-
-		/*
-		 * If this is a control chunk, this is our last
-		 * reference. Free data chunks after they've been
-		 * acknowledged or have failed.
+			pr_debug("*** Chunk:%p[%s] %s 0x%x, length:%d, chunk->skb->len:%d, rtt_in_progress:%d\n",
+				 chunk,
+				 sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
+				 chunk->has_tsn ? "TSN" : "No TSN",
+				 chunk->has_tsn ? ntohl(chunk->subh.data_hdr->tsn) : 0,
+				 ntohs(chunk->chunk_hdr->length), chunk->skb->len,
+				 chunk->rtt_in_progress);
+
+			/* If this is a control chunk, this is our last
+			 * reference. Free data chunks after they've been
+			 * acknowledged or have failed.
+			 * Re-queue auth chunks if needed.
+			 */
+			pkt_size -= WORD_ROUND(chunk->skb->len);
+
+			if (!sctp_chunk_is_data(chunk) && chunk != packet->auth)
+				sctp_chunk_free(chunk);
+
+			if (!pkt_size)
+				break;
+		}
+
+		/* SCTP-AUTH, Section 6.2
+		 *    The sender MUST calculate the MAC as described in RFC2104 [2]
+		 *    using the hash function H as described by the MAC Identifier and
+		 *    the shared association key K based on the endpoint pair shared key
+		 *    described by the shared key identifier.  The 'data' used for the
+		 *    computation of the AUTH-chunk is given by the AUTH chunk with its
+		 *    HMAC field set to zero (as shown in Figure 6) followed by all
+		 *    chunks that are placed after the AUTH chunk in the SCTP packet.
 		 */
-		if (!sctp_chunk_is_data(chunk))
-			sctp_chunk_free(chunk);
-	}
+		if (auth)
+			sctp_auth_calculate_hmac(asoc, nskb,
+						 (struct sctp_auth_chunk *)auth,
+						 gfp);
+
+		if (packet->auth) {
+			if (!list_empty(&packet->chunk_list)) {
+				/* We will generate more packets, so re-queue
+				 * auth chunk.
+				 */
+				list_add(&packet->auth->list,
+					 &packet->chunk_list);
+			} else {
+				sctp_chunk_free(packet->auth);
+				packet->auth = NULL;
+			}
+		}
 
-	/* SCTP-AUTH, Section 6.2
-	 *    The sender MUST calculate the MAC as described in RFC2104 [2]
-	 *    using the hash function H as described by the MAC Identifier and
-	 *    the shared association key K based on the endpoint pair shared key
-	 *    described by the shared key identifier.  The 'data' used for the
-	 *    computation of the AUTH-chunk is given by the AUTH chunk with its
-	 *    HMAC field set to zero (as shown in Figure 6) followed by all
-	 *    chunks that are placed after the AUTH chunk in the SCTP packet.
-	 */
-	if (auth)
-		sctp_auth_calculate_hmac(asoc, nskb,
-					 (struct sctp_auth_chunk *)auth,
-					 gfp);
+		if (!gso)
+			break;
+
+		if (skb_gro_receive(&head, nskb))
+			goto nomem;
+		nskb = NULL;
+		if (WARN_ON_ONCE(skb_shinfo(head)->gso_segs >=
+				 sk->sk_gso_max_segs))
+			goto nomem;
+	} while (!list_empty(&packet->chunk_list));
 
 	/* 2) Calculate the Adler-32 checksum of the whole packet,
 	 *    including the SCTP common header and all the
@@ -532,16 +635,18 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 	 *
 	 * Note: Adler-32 is no longer applicable, as has been replaced
 	 * by CRC32-C as described in <draft-ietf-tsvwg-sctpcsum-02.txt>.
+	 *
+	 * If it's a GSO packet, it's postponed to sctp_skb_segment.
 	 */
-	if (!sctp_checksum_disable) {
-		if (!(dst->dev->features & NETIF_F_SCTP_CRC) ||
-		    (dst_xfrm(dst) != NULL) || packet->ipfragok) {
-			sh->checksum = sctp_compute_cksum(nskb, 0);
+	if (!sctp_checksum_disable || gso) {
+		if (!gso && (!(dst->dev->features & NETIF_F_SCTP_CRC) ||
+			     dst_xfrm(dst) || packet->ipfragok)) {
+			sh->checksum = sctp_compute_cksum(head, 0);
 		} else {
 			/* no need to seed pseudo checksum for SCTP */
-			nskb->ip_summed = CHECKSUM_PARTIAL;
-			nskb->csum_start = skb_transport_header(nskb) - nskb->head;
-			nskb->csum_offset = offsetof(struct sctphdr, checksum);
+			head->ip_summed = CHECKSUM_PARTIAL;
+			head->csum_start = skb_transport_header(head) - head->head;
+			head->csum_offset = offsetof(struct sctphdr, checksum);
 		}
 	}
 
@@ -557,7 +662,7 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 	 * Note: The works for IPv6 layer checks this bit too later
 	 * in transmission.  See IP6_ECN_flow_xmit().
 	 */
-	tp->af_specific->ecn_capable(nskb->sk);
+	tp->af_specific->ecn_capable(sk);
 
 	/* Set up the IP options.  */
 	/* BUG: not implemented
@@ -566,7 +671,7 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 
 	/* Dump that on IP!  */
 	if (asoc) {
-		asoc->stats.opackets++;
+		asoc->stats.opackets += pktcount;
 		if (asoc->peer.last_sent_to != tp)
 			/* Considering the multiple CPU scenario, this is a
 			 * "correcter" place for last_sent_to.  --xguo
@@ -589,16 +694,36 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
 		}
 	}
 
-	pr_debug("***sctp_transmit_packet*** skb->len:%d\n", nskb->len);
+	pr_debug("***sctp_transmit_packet*** skb->len:%d\n", head->len);
 
-	nskb->ignore_df = packet->ipfragok;
-	tp->af_specific->sctp_xmit(nskb, tp);
+	if (gso) {
+		/* Cleanup our debris for IP stacks */
+		memset(head->cb, 0, max(sizeof(struct inet_skb_parm),
+					sizeof(struct inet6_skb_parm)));
+
+		skb_shinfo(head)->gso_segs = pktcount;
+		skb_shinfo(head)->gso_size = GSO_BY_FRAGS;
+
+		/* We have to refresh this in case we are xmiting to
+		 * more than one transport at a time
+		 */
+		rcu_read_lock();
+		if (__sk_dst_get(sk) != tp->dst) {
+			dst_hold(tp->dst);
+			sk_setup_caps(sk, tp->dst);
+		}
+		rcu_read_unlock();
+	}
+	head->ignore_df = packet->ipfragok;
+	tp->af_specific->sctp_xmit(head, tp);
 
 out:
 	sctp_packet_reset(packet);
 	return err;
 no_route:
-	kfree_skb(nskb);
+	kfree_skb(head);
+	if (nskb != head)
+		kfree_skb(nskb);
 
 	if (asoc)
 		IP_INC_STATS(sock_net(asoc->base.sk), IPSTATS_MIB_OUTNOROUTES);
@@ -623,6 +748,8 @@ err:
 	}
 	goto out;
 nomem:
+	if (packet->auth && list_empty(&packet->auth->list))
+		sctp_chunk_free(packet->auth);
 	err = -ENOMEM;
 	goto err;
 }
@@ -751,39 +878,74 @@ static sctp_xmit_t sctp_packet_will_fit(struct sctp_packet *packet,
 					struct sctp_chunk *chunk,
 					u16 chunk_len)
 {
-	size_t psize;
-	size_t pmtu;
-	int too_big;
+	size_t psize, pmtu, maxsize;
 	sctp_xmit_t retval = SCTP_XMIT_OK;
 
 	psize = packet->size;
-	pmtu  = ((packet->transport->asoc) ?
-		(packet->transport->asoc->pathmtu) :
-		(packet->transport->pathmtu));
-
-	too_big = (psize + chunk_len > pmtu);
+	if (packet->transport->asoc)
+		pmtu = packet->transport->asoc->pathmtu;
+	else
+		pmtu = packet->transport->pathmtu;
 
 	/* Decide if we need to fragment or resubmit later. */
-	if (too_big) {
-		/* It's OK to fragmet at IP level if any one of the following
+	if (psize + chunk_len > pmtu) {
+		/* It's OK to fragment at IP level if any one of the following
 		 * is true:
-		 * 	1. The packet is empty (meaning this chunk is greater
-		 * 	   the MTU)
-		 * 	2. The chunk we are adding is a control chunk
-		 * 	3. The packet doesn't have any data in it yet and data
-		 * 	requires authentication.
+		 *	1. The packet is empty (meaning this chunk is greater
+		 *	   the MTU)
+		 *	2. The packet doesn't have any data in it yet and data
+		 *	   requires authentication.
 		 */
-		if (sctp_packet_empty(packet) || !sctp_chunk_is_data(chunk) ||
+		if (sctp_packet_empty(packet) ||
 		    (!packet->has_data && chunk->auth)) {
 			/* We no longer do re-fragmentation.
 			 * Just fragment at the IP layer, if we
 			 * actually hit this condition
 			 */
 			packet->ipfragok = 1;
-		} else {
-			retval = SCTP_XMIT_PMTU_FULL;
+			goto out;
 		}
+
+		/* Similarly, if this chunk was built before a PMTU
+		 * reduction, we have to fragment it at IP level now. So
+		 * if the packet already contains something, we need to
+		 * flush.
+		 */
+		maxsize = pmtu - packet->overhead;
+		if (packet->auth)
+			maxsize -= WORD_ROUND(packet->auth->skb->len);
+		if (chunk_len > maxsize)
+			retval = SCTP_XMIT_PMTU_FULL;
+
+		/* It is also okay to fragment if the chunk we are
+		 * adding is a control chunk, but only if current packet
+		 * is not a GSO one otherwise it causes fragmentation of
+		 * a large frame. So in this case we allow the
+		 * fragmentation by forcing it to be in a new packet.
+		 */
+		if (!sctp_chunk_is_data(chunk) && packet->has_data)
+			retval = SCTP_XMIT_PMTU_FULL;
+
+		if (psize + chunk_len > packet->max_size)
+			/* Hit GSO/PMTU limit, gotta flush */
+			retval = SCTP_XMIT_PMTU_FULL;
+
+		if (!packet->transport->burst_limited &&
+		    psize + chunk_len > (packet->transport->cwnd >> 1))
+			/* Do not allow a single GSO packet to use more
+			 * than half of cwnd.
+			 */
+			retval = SCTP_XMIT_PMTU_FULL;
+
+		if (packet->transport->burst_limited &&
+		    psize + chunk_len > (packet->transport->burst_limited >> 1))
+			/* Do not allow a single GSO packet to use more
+			 * than half of original cwnd.
+			 */
+			retval = SCTP_XMIT_PMTU_FULL;
+		/* Otherwise it will fit in the GSO packet */
 	}
 
+out:
 	return retval;
 }