Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1359 insertions, 0 deletions

diff --git a/net/sctp/stream_interleave.c b/net/sctp/stream_interleave.c
new file mode 100644
index 000000000..4fbd6d052
--- /dev/null
+++ b/net/sctp/stream_interleave.c
@@ -0,0 +1,1359 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* SCTP kernel implementation
+ * (C) Copyright Red Hat Inc. 2017
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * These functions implement sctp stream message interleaving, mostly
+ * including I-DATA and I-FORWARD-TSN chunks process.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email addresched(es):
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *    Xin Long <lucien.xin@gmail.com>
+ */
+
+#include <net/busy_poll.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+#include <net/sctp/ulpevent.h>
+#include <linux/sctp.h>
+
+static struct sctp_chunk *sctp_make_idatafrag_empty(
+					const struct sctp_association *asoc,
+					const struct sctp_sndrcvinfo *sinfo,
+					int len, __u8 flags, gfp_t gfp)
+{
+	struct sctp_chunk *retval;
+	struct sctp_idatahdr dp;
+
+	memset(&dp, 0, sizeof(dp));
+	dp.stream = htons(sinfo->sinfo_stream);
+
+	if (sinfo->sinfo_flags & SCTP_UNORDERED)
+		flags |= SCTP_DATA_UNORDERED;
+
+	retval = sctp_make_idata(asoc, flags, sizeof(dp) + len, gfp);
+	if (!retval)
+		return NULL;
+
+	retval->subh.idata_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
+	memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
+
+	return retval;
+}
+
+static void sctp_chunk_assign_mid(struct sctp_chunk *chunk)
+{
+	struct sctp_stream *stream;
+	struct sctp_chunk *lchunk;
+	__u32 cfsn = 0;
+	__u16 sid;
+
+	if (chunk->has_mid)
+		return;
+
+	sid = sctp_chunk_stream_no(chunk);
+	stream = &chunk->asoc->stream;
+
+	list_for_each_entry(lchunk, &chunk->msg->chunks, frag_list) {
+		struct sctp_idatahdr *hdr;
+		__u32 mid;
+
+		lchunk->has_mid = 1;
+
+		hdr = lchunk->subh.idata_hdr;
+
+		if (lchunk->chunk_hdr->flags & SCTP_DATA_FIRST_FRAG)
+			hdr->ppid = lchunk->sinfo.sinfo_ppid;
+		else
+			hdr->fsn = htonl(cfsn++);
+
+		if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
+			mid = lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG ?
+				sctp_mid_uo_next(stream, out, sid) :
+				sctp_mid_uo_peek(stream, out, sid);
+		} else {
+			mid = lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG ?
+				sctp_mid_next(stream, out, sid) :
+				sctp_mid_peek(stream, out, sid);
+		}
+		hdr->mid = htonl(mid);
+	}
+}
+
+static bool sctp_validate_data(struct sctp_chunk *chunk)
+{
+	struct sctp_stream *stream;
+	__u16 sid, ssn;
+
+	if (chunk->chunk_hdr->type != SCTP_CID_DATA)
+		return false;
+
+	if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED)
+		return true;
+
+	stream = &chunk->asoc->stream;
+	sid = sctp_chunk_stream_no(chunk);
+	ssn = ntohs(chunk->subh.data_hdr->ssn);
+
+	return !SSN_lt(ssn, sctp_ssn_peek(stream, in, sid));
+}
+
+static bool sctp_validate_idata(struct sctp_chunk *chunk)
+{
+	struct sctp_stream *stream;
+	__u32 mid;
+	__u16 sid;
+
+	if (chunk->chunk_hdr->type != SCTP_CID_I_DATA)
+		return false;
+
+	if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED)
+		return true;
+
+	stream = &chunk->asoc->stream;
+	sid = sctp_chunk_stream_no(chunk);
+	mid = ntohl(chunk->subh.idata_hdr->mid);
+
+	return !MID_lt(mid, sctp_mid_peek(stream, in, sid));
+}
+
+static void sctp_intl_store_reasm(struct sctp_ulpq *ulpq,
+				  struct sctp_ulpevent *event)
+{
+	struct sctp_ulpevent *cevent;
+	struct sk_buff *pos, *loc;
+
+	pos = skb_peek_tail(&ulpq->reasm);
+	if (!pos) {
+		__skb_queue_tail(&ulpq->reasm, sctp_event2skb(event));
+		return;
+	}
+
+	cevent = sctp_skb2event(pos);
+
+	if (event->stream == cevent->stream &&
+	    event->mid == cevent->mid &&
+	    (cevent->msg_flags & SCTP_DATA_FIRST_FRAG ||
+	     (!(event->msg_flags & SCTP_DATA_FIRST_FRAG) &&
+	      event->fsn > cevent->fsn))) {
+		__skb_queue_tail(&ulpq->reasm, sctp_event2skb(event));
+		return;
+	}
+
+	if ((event->stream == cevent->stream &&
+	     MID_lt(cevent->mid, event->mid)) ||
+	    event->stream > cevent->stream) {
+		__skb_queue_tail(&ulpq->reasm, sctp_event2skb(event));
+		return;
+	}
+
+	loc = NULL;
+	skb_queue_walk(&ulpq->reasm, pos) {
+		cevent = sctp_skb2event(pos);
+
+		if (event->stream < cevent->stream ||
+		    (event->stream == cevent->stream &&
+		     MID_lt(event->mid, cevent->mid))) {
+			loc = pos;
+			break;
+		}
+		if (event->stream == cevent->stream &&
+		    event->mid == cevent->mid &&
+		    !(cevent->msg_flags & SCTP_DATA_FIRST_FRAG) &&
+		    (event->msg_flags & SCTP_DATA_FIRST_FRAG ||
+		     event->fsn < cevent->fsn)) {
+			loc = pos;
+			break;
+		}
+	}
+
+	if (!loc)
+		__skb_queue_tail(&ulpq->reasm, sctp_event2skb(event));
+	else
+		__skb_queue_before(&ulpq->reasm, loc, sctp_event2skb(event));
+}
+
+static struct sctp_ulpevent *sctp_intl_retrieve_partial(
+						struct sctp_ulpq *ulpq,
+						struct sctp_ulpevent *event)
+{
+	struct sk_buff *first_frag = NULL;
+	struct sk_buff *last_frag = NULL;
+	struct sctp_ulpevent *retval;
+	struct sctp_stream_in *sin;
+	struct sk_buff *pos;
+	__u32 next_fsn = 0;
+	int is_last = 0;
+
+	sin = sctp_stream_in(&ulpq->asoc->stream, event->stream);
+
+	skb_queue_walk(&ulpq->reasm, pos) {
+		struct sctp_ulpevent *cevent = sctp_skb2event(pos);
+
+		if (cevent->stream < event->stream)
+			continue;
+
+		if (cevent->stream > event->stream ||
+		    cevent->mid != sin->mid)
+			break;
+
+		switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {
+		case SCTP_DATA_FIRST_FRAG:
+			goto out;
+		case SCTP_DATA_MIDDLE_FRAG:
+			if (!first_frag) {
+				if (cevent->fsn == sin->fsn) {
+					first_frag = pos;
+					last_frag = pos;
+					next_fsn = cevent->fsn + 1;
+				}
+			} else if (cevent->fsn == next_fsn) {
+				last_frag = pos;
+				next_fsn++;
+			} else {
+				goto out;
+			}
+			break;
+		case SCTP_DATA_LAST_FRAG:
+			if (!first_frag) {
+				if (cevent->fsn == sin->fsn) {
+					first_frag = pos;
+					last_frag = pos;
+					next_fsn = 0;
+					is_last = 1;
+				}
+			} else if (cevent->fsn == next_fsn) {
+				last_frag = pos;
+				next_fsn = 0;
+				is_last = 1;
+			}
+			goto out;
+		default:
+			goto out;
+		}
+	}
+
+out:
+	if (!first_frag)
+		return NULL;
+
+	retval = sctp_make_reassembled_event(ulpq->asoc->base.net, &ulpq->reasm,
+					     first_frag, last_frag);
+	if (retval) {
+		sin->fsn = next_fsn;
+		if (is_last) {
+			retval->msg_flags |= MSG_EOR;
+			sin->pd_mode = 0;
+		}
+	}
+
+	return retval;
+}
+
+static struct sctp_ulpevent *sctp_intl_retrieve_reassembled(
+						struct sctp_ulpq *ulpq,
+						struct sctp_ulpevent *event)
+{
+	struct sctp_association *asoc = ulpq->asoc;
+	struct sk_buff *pos, *first_frag = NULL;
+	struct sctp_ulpevent *retval = NULL;
+	struct sk_buff *pd_first = NULL;
+	struct sk_buff *pd_last = NULL;
+	struct sctp_stream_in *sin;
+	__u32 next_fsn = 0;
+	__u32 pd_point = 0;
+	__u32 pd_len = 0;
+	__u32 mid = 0;
+
+	sin = sctp_stream_in(&ulpq->asoc->stream, event->stream);
+
+	skb_queue_walk(&ulpq->reasm, pos) {
+		struct sctp_ulpevent *cevent = sctp_skb2event(pos);
+
+		if (cevent->stream < event->stream)
+			continue;
+		if (cevent->stream > event->stream)
+			break;
+
+		if (MID_lt(cevent->mid, event->mid))
+			continue;
+		if (MID_lt(event->mid, cevent->mid))
+			break;
+
+		switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {
+		case SCTP_DATA_FIRST_FRAG:
+			if (cevent->mid == sin->mid) {
+				pd_first = pos;
+				pd_last = pos;
+				pd_len = pos->len;
+			}
+
+			first_frag = pos;
+			next_fsn = 0;
+			mid = cevent->mid;
+			break;
+
+		case SCTP_DATA_MIDDLE_FRAG:
+			if (first_frag && cevent->mid == mid &&
+			    cevent->fsn == next_fsn) {
+				next_fsn++;
+				if (pd_first) {
+					pd_last = pos;
+					pd_len += pos->len;
+				}
+			} else {
+				first_frag = NULL;
+			}
+			break;
+
+		case SCTP_DATA_LAST_FRAG:
+			if (first_frag && cevent->mid == mid &&
+			    cevent->fsn == next_fsn)
+				goto found;
+			else
+				first_frag = NULL;
+			break;
+		}
+	}
+
+	if (!pd_first)
+		goto out;
+
+	pd_point = sctp_sk(asoc->base.sk)->pd_point;
+	if (pd_point && pd_point <= pd_len) {
+		retval = sctp_make_reassembled_event(asoc->base.net,
+						     &ulpq->reasm,
+						     pd_first, pd_last);
+		if (retval) {
+			sin->fsn = next_fsn;
+			sin->pd_mode = 1;
+		}
+	}
+	goto out;
+
+found:
+	retval = sctp_make_reassembled_event(asoc->base.net, &ulpq->reasm,
+					     first_frag, pos);
+	if (retval)
+		retval->msg_flags |= MSG_EOR;
+
+out:
+	return retval;
+}
+
+static struct sctp_ulpevent *sctp_intl_reasm(struct sctp_ulpq *ulpq,
+					     struct sctp_ulpevent *event)
+{
+	struct sctp_ulpevent *retval = NULL;
+	struct sctp_stream_in *sin;
+
+	if (SCTP_DATA_NOT_FRAG == (event->msg_flags & SCTP_DATA_FRAG_MASK)) {
+		event->msg_flags |= MSG_EOR;
+		return event;
+	}
+
+	sctp_intl_store_reasm(ulpq, event);
+
+	sin = sctp_stream_in(&ulpq->asoc->stream, event->stream);
+	if (sin->pd_mode && event->mid == sin->mid &&
+	    event->fsn == sin->fsn)
+		retval = sctp_intl_retrieve_partial(ulpq, event);
+
+	if (!retval)
+		retval = sctp_intl_retrieve_reassembled(ulpq, event);
+
+	return retval;
+}
+
+static void sctp_intl_store_ordered(struct sctp_ulpq *ulpq,
+				    struct sctp_ulpevent *event)
+{
+	struct sctp_ulpevent *cevent;
+	struct sk_buff *pos, *loc;
+
+	pos = skb_peek_tail(&ulpq->lobby);
+	if (!pos) {
+		__skb_queue_tail(&ulpq->lobby, sctp_event2skb(event));
+		return;
+	}
+
+	cevent = (struct sctp_ulpevent *)pos->cb;
+	if (event->stream == cevent->stream &&
+	    MID_lt(cevent->mid, event->mid)) {
+		__skb_queue_tail(&ulpq->lobby, sctp_event2skb(event));
+		return;
+	}
+
+	if (event->stream > cevent->stream) {
+		__skb_queue_tail(&ulpq->lobby, sctp_event2skb(event));
+		return;
+	}
+
+	loc = NULL;
+	skb_queue_walk(&ulpq->lobby, pos) {
+		cevent = (struct sctp_ulpevent *)pos->cb;
+
+		if (cevent->stream > event->stream) {
+			loc = pos;
+			break;
+		}
+		if (cevent->stream == event->stream &&
+		    MID_lt(event->mid, cevent->mid)) {
+			loc = pos;
+			break;
+		}
+	}
+
+	if (!loc)
+		__skb_queue_tail(&ulpq->lobby, sctp_event2skb(event));
+	else
+		__skb_queue_before(&ulpq->lobby, loc, sctp_event2skb(event));
+}
+
+static void sctp_intl_retrieve_ordered(struct sctp_ulpq *ulpq,
+				       struct sctp_ulpevent *event)
+{
+	struct sk_buff_head *event_list;
+	struct sctp_stream *stream;
+	struct sk_buff *pos, *tmp;
+	__u16 sid = event->stream;
+
+	stream  = &ulpq->asoc->stream;
+	event_list = (struct sk_buff_head *)sctp_event2skb(event)->prev;
+
+	sctp_skb_for_each(pos, &ulpq->lobby, tmp) {
+		struct sctp_ulpevent *cevent = (struct sctp_ulpevent *)pos->cb;
+
+		if (cevent->stream > sid)
+			break;
+
+		if (cevent->stream < sid)
+			continue;
+
+		if (cevent->mid != sctp_mid_peek(stream, in, sid))
+			break;
+
+		sctp_mid_next(stream, in, sid);
+
+		__skb_unlink(pos, &ulpq->lobby);
+
+		__skb_queue_tail(event_list, pos);
+	}
+}
+
+static struct sctp_ulpevent *sctp_intl_order(struct sctp_ulpq *ulpq,
+					     struct sctp_ulpevent *event)
+{
+	struct sctp_stream *stream;
+	__u16 sid;
+
+	stream  = &ulpq->asoc->stream;
+	sid = event->stream;
+
+	if (event->mid != sctp_mid_peek(stream, in, sid)) {
+		sctp_intl_store_ordered(ulpq, event);
+		return NULL;
+	}
+
+	sctp_mid_next(stream, in, sid);
+
+	sctp_intl_retrieve_ordered(ulpq, event);
+
+	return event;
+}
+
+static int sctp_enqueue_event(struct sctp_ulpq *ulpq,
+			      struct sk_buff_head *skb_list)
+{
+	struct sock *sk = ulpq->asoc->base.sk;
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_ulpevent *event;
+	struct sk_buff *skb;
+
+	skb = __skb_peek(skb_list);
+	event = sctp_skb2event(skb);
+
+	if (sk->sk_shutdown & RCV_SHUTDOWN &&
+	    (sk->sk_shutdown & SEND_SHUTDOWN ||
+	     !sctp_ulpevent_is_notification(event)))
+		goto out_free;
+
+	if (!sctp_ulpevent_is_notification(event)) {
+		sk_mark_napi_id(sk, skb);
+		sk_incoming_cpu_update(sk);
+	}
+
+	if (!sctp_ulpevent_is_enabled(event, ulpq->asoc->subscribe))
+		goto out_free;
+
+	if (skb_list)
+		skb_queue_splice_tail_init(skb_list,
+					   &sk->sk_receive_queue);
+	else
+		__skb_queue_tail(&sk->sk_receive_queue, skb);
+
+	if (!sp->data_ready_signalled) {
+		sp->data_ready_signalled = 1;
+		sk->sk_data_ready(sk);
+	}
+
+	return 1;
+
+out_free:
+	if (skb_list)
+		sctp_queue_purge_ulpevents(skb_list);
+	else
+		sctp_ulpevent_free(event);
+
+	return 0;
+}
+
+static void sctp_intl_store_reasm_uo(struct sctp_ulpq *ulpq,
+				     struct sctp_ulpevent *event)
+{
+	struct sctp_ulpevent *cevent;
+	struct sk_buff *pos;
+
+	pos = skb_peek_tail(&ulpq->reasm_uo);
+	if (!pos) {
+		__skb_queue_tail(&ulpq->reasm_uo, sctp_event2skb(event));
+		return;
+	}
+
+	cevent = sctp_skb2event(pos);
+
+	if (event->stream == cevent->stream &&
+	    event->mid == cevent->mid &&
+	    (cevent->msg_flags & SCTP_DATA_FIRST_FRAG ||
+	     (!(event->msg_flags & SCTP_DATA_FIRST_FRAG) &&
+	      event->fsn > cevent->fsn))) {
+		__skb_queue_tail(&ulpq->reasm_uo, sctp_event2skb(event));
+		return;
+	}
+
+	if ((event->stream == cevent->stream &&
+	     MID_lt(cevent->mid, event->mid)) ||
+	    event->stream > cevent->stream) {
+		__skb_queue_tail(&ulpq->reasm_uo, sctp_event2skb(event));
+		return;
+	}
+
+	skb_queue_walk(&ulpq->reasm_uo, pos) {
+		cevent = sctp_skb2event(pos);
+
+		if (event->stream < cevent->stream ||
+		    (event->stream == cevent->stream &&
+		     MID_lt(event->mid, cevent->mid)))
+			break;
+
+		if (event->stream == cevent->stream &&
+		    event->mid == cevent->mid &&
+		    !(cevent->msg_flags & SCTP_DATA_FIRST_FRAG) &&
+		    (event->msg_flags & SCTP_DATA_FIRST_FRAG ||
+		     event->fsn < cevent->fsn))
+			break;
+	}
+
+	__skb_queue_before(&ulpq->reasm_uo, pos, sctp_event2skb(event));
+}
+
+static struct sctp_ulpevent *sctp_intl_retrieve_partial_uo(
+						struct sctp_ulpq *ulpq,
+						struct sctp_ulpevent *event)
+{
+	struct sk_buff *first_frag = NULL;
+	struct sk_buff *last_frag = NULL;
+	struct sctp_ulpevent *retval;
+	struct sctp_stream_in *sin;
+	struct sk_buff *pos;
+	__u32 next_fsn = 0;
+	int is_last = 0;
+
+	sin = sctp_stream_in(&ulpq->asoc->stream, event->stream);
+
+	skb_queue_walk(&ulpq->reasm_uo, pos) {
+		struct sctp_ulpevent *cevent = sctp_skb2event(pos);
+
+		if (cevent->stream < event->stream)
+			continue;
+		if (cevent->stream > event->stream)
+			break;
+
+		if (MID_lt(cevent->mid, sin->mid_uo))
+			continue;
+		if (MID_lt(sin->mid_uo, cevent->mid))
+			break;
+
+		switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {
+		case SCTP_DATA_FIRST_FRAG:
+			goto out;
+		case SCTP_DATA_MIDDLE_FRAG:
+			if (!first_frag) {
+				if (cevent->fsn == sin->fsn_uo) {
+					first_frag = pos;
+					last_frag = pos;
+					next_fsn = cevent->fsn + 1;
+				}
+			} else if (cevent->fsn == next_fsn) {
+				last_frag = pos;
+				next_fsn++;
+			} else {
+				goto out;
+			}
+			break;
+		case SCTP_DATA_LAST_FRAG:
+			if (!first_frag) {
+				if (cevent->fsn == sin->fsn_uo) {
+					first_frag = pos;
+					last_frag = pos;
+					next_fsn = 0;
+					is_last = 1;
+				}
+			} else if (cevent->fsn == next_fsn) {
+				last_frag = pos;
+				next_fsn = 0;
+				is_last = 1;
+			}
+			goto out;
+		default:
+			goto out;
+		}
+	}
+
+out:
+	if (!first_frag)
+		return NULL;
+
+	retval = sctp_make_reassembled_event(ulpq->asoc->base.net,
+					     &ulpq->reasm_uo, first_frag,
+					     last_frag);
+	if (retval) {
+		sin->fsn_uo = next_fsn;
+		if (is_last) {
+			retval->msg_flags |= MSG_EOR;
+			sin->pd_mode_uo = 0;
+		}
+	}
+
+	return retval;
+}
+
+static struct sctp_ulpevent *sctp_intl_retrieve_reassembled_uo(
+						struct sctp_ulpq *ulpq,
+						struct sctp_ulpevent *event)
+{
+	struct sctp_association *asoc = ulpq->asoc;
+	struct sk_buff *pos, *first_frag = NULL;
+	struct sctp_ulpevent *retval = NULL;
+	struct sk_buff *pd_first = NULL;
+	struct sk_buff *pd_last = NULL;
+	struct sctp_stream_in *sin;
+	__u32 next_fsn = 0;
+	__u32 pd_point = 0;
+	__u32 pd_len = 0;
+	__u32 mid = 0;
+
+	sin = sctp_stream_in(&ulpq->asoc->stream, event->stream);
+
+	skb_queue_walk(&ulpq->reasm_uo, pos) {
+		struct sctp_ulpevent *cevent = sctp_skb2event(pos);
+
+		if (cevent->stream < event->stream)
+			continue;
+		if (cevent->stream > event->stream)
+			break;
+
+		if (MID_lt(cevent->mid, event->mid))
+			continue;
+		if (MID_lt(event->mid, cevent->mid))
+			break;
+
+		switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {
+		case SCTP_DATA_FIRST_FRAG:
+			if (!sin->pd_mode_uo) {
+				sin->mid_uo = cevent->mid;
+				pd_first = pos;
+				pd_last = pos;
+				pd_len = pos->len;
+			}
+
+			first_frag = pos;
+			next_fsn = 0;
+			mid = cevent->mid;
+			break;
+
+		case SCTP_DATA_MIDDLE_FRAG:
+			if (first_frag && cevent->mid == mid &&
+			    cevent->fsn == next_fsn) {
+				next_fsn++;
+				if (pd_first) {
+					pd_last = pos;
+					pd_len += pos->len;
+				}
+			} else {
+				first_frag = NULL;
+			}
+			break;
+
+		case SCTP_DATA_LAST_FRAG:
+			if (first_frag && cevent->mid == mid &&
+			    cevent->fsn == next_fsn)
+				goto found;
+			else
+				first_frag = NULL;
+			break;
+		}
+	}
+
+	if (!pd_first)
+		goto out;
+
+	pd_point = sctp_sk(asoc->base.sk)->pd_point;
+	if (pd_point && pd_point <= pd_len) {
+		retval = sctp_make_reassembled_event(asoc->base.net,
+						     &ulpq->reasm_uo,
+						     pd_first, pd_last);
+		if (retval) {
+			sin->fsn_uo = next_fsn;
+			sin->pd_mode_uo = 1;
+		}
+	}
+	goto out;
+
+found:
+	retval = sctp_make_reassembled_event(asoc->base.net, &ulpq->reasm_uo,
+					     first_frag, pos);
+	if (retval)
+		retval->msg_flags |= MSG_EOR;
+
+out:
+	return retval;
+}
+
+static struct sctp_ulpevent *sctp_intl_reasm_uo(struct sctp_ulpq *ulpq,
+						struct sctp_ulpevent *event)
+{
+	struct sctp_ulpevent *retval = NULL;
+	struct sctp_stream_in *sin;
+
+	if (SCTP_DATA_NOT_FRAG == (event->msg_flags & SCTP_DATA_FRAG_MASK)) {
+		event->msg_flags |= MSG_EOR;
+		return event;
+	}
+
+	sctp_intl_store_reasm_uo(ulpq, event);
+
+	sin = sctp_stream_in(&ulpq->asoc->stream, event->stream);
+	if (sin->pd_mode_uo && event->mid == sin->mid_uo &&
+	    event->fsn == sin->fsn_uo)
+		retval = sctp_intl_retrieve_partial_uo(ulpq, event);
+
+	if (!retval)
+		retval = sctp_intl_retrieve_reassembled_uo(ulpq, event);
+
+	return retval;
+}
+
+static struct sctp_ulpevent *sctp_intl_retrieve_first_uo(struct sctp_ulpq *ulpq)
+{
+	struct sctp_stream_in *csin, *sin = NULL;
+	struct sk_buff *first_frag = NULL;
+	struct sk_buff *last_frag = NULL;
+	struct sctp_ulpevent *retval;
+	struct sk_buff *pos;
+	__u32 next_fsn = 0;
+	__u16 sid = 0;
+
+	skb_queue_walk(&ulpq->reasm_uo, pos) {
+		struct sctp_ulpevent *cevent = sctp_skb2event(pos);
+
+		csin = sctp_stream_in(&ulpq->asoc->stream, cevent->stream);
+		if (csin->pd_mode_uo)
+			continue;
+
+		switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {
+		case SCTP_DATA_FIRST_FRAG:
+			if (first_frag)
+				goto out;
+			first_frag = pos;
+			last_frag = pos;
+			next_fsn = 0;
+			sin = csin;
+			sid = cevent->stream;
+			sin->mid_uo = cevent->mid;
+			break;
+		case SCTP_DATA_MIDDLE_FRAG:
+			if (!first_frag)
+				break;
+			if (cevent->stream == sid &&
+			    cevent->mid == sin->mid_uo &&
+			    cevent->fsn == next_fsn) {
+				next_fsn++;
+				last_frag = pos;
+			} else {
+				goto out;
+			}
+			break;
+		case SCTP_DATA_LAST_FRAG:
+			if (first_frag)
+				goto out;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (!first_frag)
+		return NULL;
+
+out:
+	retval = sctp_make_reassembled_event(ulpq->asoc->base.net,
+					     &ulpq->reasm_uo, first_frag,
+					     last_frag);
+	if (retval) {
+		sin->fsn_uo = next_fsn;
+		sin->pd_mode_uo = 1;
+	}
+
+	return retval;
+}
+
+static int sctp_ulpevent_idata(struct sctp_ulpq *ulpq,
+			       struct sctp_chunk *chunk, gfp_t gfp)
+{
+	struct sctp_ulpevent *event;
+	struct sk_buff_head temp;
+	int event_eor = 0;
+
+	event = sctp_ulpevent_make_rcvmsg(chunk->asoc, chunk, gfp);
+	if (!event)
+		return -ENOMEM;
+
+	event->mid = ntohl(chunk->subh.idata_hdr->mid);
+	if (event->msg_flags & SCTP_DATA_FIRST_FRAG)
+		event->ppid = chunk->subh.idata_hdr->ppid;
+	else
+		event->fsn = ntohl(chunk->subh.idata_hdr->fsn);
+
+	if (!(event->msg_flags & SCTP_DATA_UNORDERED)) {
+		event = sctp_intl_reasm(ulpq, event);
+		if (event) {
+			skb_queue_head_init(&temp);
+			__skb_queue_tail(&temp, sctp_event2skb(event));
+
+			if (event->msg_flags & MSG_EOR)
+				event = sctp_intl_order(ulpq, event);
+		}
+	} else {
+		event = sctp_intl_reasm_uo(ulpq, event);
+		if (event) {
+			skb_queue_head_init(&temp);
+			__skb_queue_tail(&temp, sctp_event2skb(event));
+		}
+	}
+
+	if (event) {
+		event_eor = (event->msg_flags & MSG_EOR) ? 1 : 0;
+		sctp_enqueue_event(ulpq, &temp);
+	}
+
+	return event_eor;
+}
+
+static struct sctp_ulpevent *sctp_intl_retrieve_first(struct sctp_ulpq *ulpq)
+{
+	struct sctp_stream_in *csin, *sin = NULL;
+	struct sk_buff *first_frag = NULL;
+	struct sk_buff *last_frag = NULL;
+	struct sctp_ulpevent *retval;
+	struct sk_buff *pos;
+	__u32 next_fsn = 0;
+	__u16 sid = 0;
+
+	skb_queue_walk(&ulpq->reasm, pos) {
+		struct sctp_ulpevent *cevent = sctp_skb2event(pos);
+
+		csin = sctp_stream_in(&ulpq->asoc->stream, cevent->stream);
+		if (csin->pd_mode)
+			continue;
+
+		switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {
+		case SCTP_DATA_FIRST_FRAG:
+			if (first_frag)
+				goto out;
+			if (cevent->mid == csin->mid) {
+				first_frag = pos;
+				last_frag = pos;
+				next_fsn = 0;
+				sin = csin;
+				sid = cevent->stream;
+			}
+			break;
+		case SCTP_DATA_MIDDLE_FRAG:
+			if (!first_frag)
+				break;
+			if (cevent->stream == sid &&
+			    cevent->mid == sin->mid &&
+			    cevent->fsn == next_fsn) {
+				next_fsn++;
+				last_frag = pos;
+			} else {
+				goto out;
+			}
+			break;
+		case SCTP_DATA_LAST_FRAG:
+			if (first_frag)
+				goto out;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (!first_frag)
+		return NULL;
+
+out:
+	retval = sctp_make_reassembled_event(ulpq->asoc->base.net,
+					     &ulpq->reasm, first_frag,
+					     last_frag);
+	if (retval) {
+		sin->fsn = next_fsn;
+		sin->pd_mode = 1;
+	}
+
+	return retval;
+}
+
+static void sctp_intl_start_pd(struct sctp_ulpq *ulpq, gfp_t gfp)
+{
+	struct sctp_ulpevent *event;
+	struct sk_buff_head temp;
+
+	if (!skb_queue_empty(&ulpq->reasm)) {
+		do {
+			event = sctp_intl_retrieve_first(ulpq);
+			if (event) {
+				skb_queue_head_init(&temp);
+				__skb_queue_tail(&temp, sctp_event2skb(event));
+				sctp_enqueue_event(ulpq, &temp);
+			}
+		} while (event);
+	}
+
+	if (!skb_queue_empty(&ulpq->reasm_uo)) {
+		do {
+			event = sctp_intl_retrieve_first_uo(ulpq);
+			if (event) {
+				skb_queue_head_init(&temp);
+				__skb_queue_tail(&temp, sctp_event2skb(event));
+				sctp_enqueue_event(ulpq, &temp);
+			}
+		} while (event);
+	}
+}
+
+static void sctp_renege_events(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk,
+			       gfp_t gfp)
+{
+	struct sctp_association *asoc = ulpq->asoc;
+	__u32 freed = 0;
+	__u16 needed;
+
+	needed = ntohs(chunk->chunk_hdr->length) -
+		 sizeof(struct sctp_idata_chunk);
+
+	if (skb_queue_empty(&asoc->base.sk->sk_receive_queue)) {
+		freed = sctp_ulpq_renege_list(ulpq, &ulpq->lobby, needed);
+		if (freed < needed)
+			freed += sctp_ulpq_renege_list(ulpq, &ulpq->reasm,
+						       needed);
+		if (freed < needed)
+			freed += sctp_ulpq_renege_list(ulpq, &ulpq->reasm_uo,
+						       needed);
+	}
+
+	if (freed >= needed && sctp_ulpevent_idata(ulpq, chunk, gfp) <= 0)
+		sctp_intl_start_pd(ulpq, gfp);
+}
+
+static void sctp_intl_stream_abort_pd(struct sctp_ulpq *ulpq, __u16 sid,
+				      __u32 mid, __u16 flags, gfp_t gfp)
+{
+	struct sock *sk = ulpq->asoc->base.sk;
+	struct sctp_ulpevent *ev = NULL;
+
+	if (!sctp_ulpevent_type_enabled(ulpq->asoc->subscribe,
+					SCTP_PARTIAL_DELIVERY_EVENT))
+		return;
+
+	ev = sctp_ulpevent_make_pdapi(ulpq->asoc, SCTP_PARTIAL_DELIVERY_ABORTED,
+				      sid, mid, flags, gfp);
+	if (ev) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		__skb_queue_tail(&sk->sk_receive_queue, sctp_event2skb(ev));
+
+		if (!sp->data_ready_signalled) {
+			sp->data_ready_signalled = 1;
+			sk->sk_data_ready(sk);
+		}
+	}
+}
+
+static void sctp_intl_reap_ordered(struct sctp_ulpq *ulpq, __u16 sid)
+{
+	struct sctp_stream *stream = &ulpq->asoc->stream;
+	struct sctp_ulpevent *cevent, *event = NULL;
+	struct sk_buff_head *lobby = &ulpq->lobby;
+	struct sk_buff *pos, *tmp;
+	struct sk_buff_head temp;
+	__u16 csid;
+	__u32 cmid;
+
+	skb_queue_head_init(&temp);
+	sctp_skb_for_each(pos, lobby, tmp) {
+		cevent = (struct sctp_ulpevent *)pos->cb;
+		csid = cevent->stream;
+		cmid = cevent->mid;
+
+		if (csid > sid)
+			break;
+
+		if (csid < sid)
+			continue;
+
+		if (!MID_lt(cmid, sctp_mid_peek(stream, in, csid)))
+			break;
+
+		__skb_unlink(pos, lobby);
+		if (!event)
+			event = sctp_skb2event(pos);
+
+		__skb_queue_tail(&temp, pos);
+	}
+
+	if (!event && pos != (struct sk_buff *)lobby) {
+		cevent = (struct sctp_ulpevent *)pos->cb;
+		csid = cevent->stream;
+		cmid = cevent->mid;
+
+		if (csid == sid && cmid == sctp_mid_peek(stream, in, csid)) {
+			sctp_mid_next(stream, in, csid);
+			__skb_unlink(pos, lobby);
+			__skb_queue_tail(&temp, pos);
+			event = sctp_skb2event(pos);
+		}
+	}
+
+	if (event) {
+		sctp_intl_retrieve_ordered(ulpq, event);
+		sctp_enqueue_event(ulpq, &temp);
+	}
+}
+
+static void sctp_intl_abort_pd(struct sctp_ulpq *ulpq, gfp_t gfp)
+{
+	struct sctp_stream *stream = &ulpq->asoc->stream;
+	__u16 sid;
+
+	for (sid = 0; sid < stream->incnt; sid++) {
+		struct sctp_stream_in *sin = SCTP_SI(stream, sid);
+		__u32 mid;
+
+		if (sin->pd_mode_uo) {
+			sin->pd_mode_uo = 0;
+
+			mid = sin->mid_uo;
+			sctp_intl_stream_abort_pd(ulpq, sid, mid, 0x1, gfp);
+		}
+
+		if (sin->pd_mode) {
+			sin->pd_mode = 0;
+
+			mid = sin->mid;
+			sctp_intl_stream_abort_pd(ulpq, sid, mid, 0, gfp);
+			sctp_mid_skip(stream, in, sid, mid);
+
+			sctp_intl_reap_ordered(ulpq, sid);
+		}
+	}
+
+	/* intl abort pd happens only when all data needs to be cleaned */
+	sctp_ulpq_flush(ulpq);
+}
+
+static inline int sctp_get_skip_pos(struct sctp_ifwdtsn_skip *skiplist,
+				    int nskips, __be16 stream, __u8 flags)
+{
+	int i;
+
+	for (i = 0; i < nskips; i++)
+		if (skiplist[i].stream == stream &&
+		    skiplist[i].flags == flags)
+			return i;
+
+	return i;
+}
+
+#define SCTP_FTSN_U_BIT	0x1
+static void sctp_generate_iftsn(struct sctp_outq *q, __u32 ctsn)
+{
+	struct sctp_ifwdtsn_skip ftsn_skip_arr[10];
+	struct sctp_association *asoc = q->asoc;
+	struct sctp_chunk *ftsn_chunk = NULL;
+	struct list_head *lchunk, *temp;
+	int nskips = 0, skip_pos;
+	struct sctp_chunk *chunk;
+	__u32 tsn;
+
+	if (!asoc->peer.prsctp_capable)
+		return;
+
+	if (TSN_lt(asoc->adv_peer_ack_point, ctsn))
+		asoc->adv_peer_ack_point = ctsn;
+
+	list_for_each_safe(lchunk, temp, &q->abandoned) {
+		chunk = list_entry(lchunk, struct sctp_chunk, transmitted_list);
+		tsn = ntohl(chunk->subh.data_hdr->tsn);
+
+		if (TSN_lte(tsn, ctsn)) {
+			list_del_init(lchunk);
+			sctp_chunk_free(chunk);
+		} else if (TSN_lte(tsn, asoc->adv_peer_ack_point + 1)) {
+			__be16 sid = chunk->subh.idata_hdr->stream;
+			__be32 mid = chunk->subh.idata_hdr->mid;
+			__u8 flags = 0;
+
+			if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED)
+				flags |= SCTP_FTSN_U_BIT;
+
+			asoc->adv_peer_ack_point = tsn;
+			skip_pos = sctp_get_skip_pos(&ftsn_skip_arr[0], nskips,
+						     sid, flags);
+			ftsn_skip_arr[skip_pos].stream = sid;
+			ftsn_skip_arr[skip_pos].reserved = 0;
+			ftsn_skip_arr[skip_pos].flags = flags;
+			ftsn_skip_arr[skip_pos].mid = mid;
+			if (skip_pos == nskips)
+				nskips++;
+			if (nskips == 10)
+				break;
+		} else {
+			break;
+		}
+	}
+
+	if (asoc->adv_peer_ack_point > ctsn)
+		ftsn_chunk = sctp_make_ifwdtsn(asoc, asoc->adv_peer_ack_point,
+					       nskips, &ftsn_skip_arr[0]);
+
+	if (ftsn_chunk) {
+		list_add_tail(&ftsn_chunk->list, &q->control_chunk_list);
+		SCTP_INC_STATS(asoc->base.net, SCTP_MIB_OUTCTRLCHUNKS);
+	}
+}
+
+#define _sctp_walk_ifwdtsn(pos, chunk, end) \
+	for (pos = chunk->subh.ifwdtsn_hdr->skip; \
+	     (void *)pos <= (void *)chunk->subh.ifwdtsn_hdr->skip + (end) - \
+			    sizeof(struct sctp_ifwdtsn_skip); pos++)
+
+#define sctp_walk_ifwdtsn(pos, ch) \
+	_sctp_walk_ifwdtsn((pos), (ch), ntohs((ch)->chunk_hdr->length) - \
+					sizeof(struct sctp_ifwdtsn_chunk))
+
+static bool sctp_validate_fwdtsn(struct sctp_chunk *chunk)
+{
+	struct sctp_fwdtsn_skip *skip;
+	__u16 incnt;
+
+	if (chunk->chunk_hdr->type != SCTP_CID_FWD_TSN)
+		return false;
+
+	incnt = chunk->asoc->stream.incnt;
+	sctp_walk_fwdtsn(skip, chunk)
+		if (ntohs(skip->stream) >= incnt)
+			return false;
+
+	return true;
+}
+
+static bool sctp_validate_iftsn(struct sctp_chunk *chunk)
+{
+	struct sctp_ifwdtsn_skip *skip;
+	__u16 incnt;
+
+	if (chunk->chunk_hdr->type != SCTP_CID_I_FWD_TSN)
+		return false;
+
+	incnt = chunk->asoc->stream.incnt;
+	sctp_walk_ifwdtsn(skip, chunk)
+		if (ntohs(skip->stream) >= incnt)
+			return false;
+
+	return true;
+}
+
+static void sctp_report_fwdtsn(struct sctp_ulpq *ulpq, __u32 ftsn)
+{
+	/* Move the Cumulattive TSN Ack ahead. */
+	sctp_tsnmap_skip(&ulpq->asoc->peer.tsn_map, ftsn);
+	/* purge the fragmentation queue */
+	sctp_ulpq_reasm_flushtsn(ulpq, ftsn);
+	/* Abort any in progress partial delivery. */
+	sctp_ulpq_abort_pd(ulpq, GFP_ATOMIC);
+}
+
+static void sctp_intl_reasm_flushtsn(struct sctp_ulpq *ulpq, __u32 ftsn)
+{
+	struct sk_buff *pos, *tmp;
+
+	skb_queue_walk_safe(&ulpq->reasm, pos, tmp) {
+		struct sctp_ulpevent *event = sctp_skb2event(pos);
+		__u32 tsn = event->tsn;
+
+		if (TSN_lte(tsn, ftsn)) {
+			__skb_unlink(pos, &ulpq->reasm);
+			sctp_ulpevent_free(event);
+		}
+	}
+
+	skb_queue_walk_safe(&ulpq->reasm_uo, pos, tmp) {
+		struct sctp_ulpevent *event = sctp_skb2event(pos);
+		__u32 tsn = event->tsn;
+
+		if (TSN_lte(tsn, ftsn)) {
+			__skb_unlink(pos, &ulpq->reasm_uo);
+			sctp_ulpevent_free(event);
+		}
+	}
+}
+
+static void sctp_report_iftsn(struct sctp_ulpq *ulpq, __u32 ftsn)
+{
+	/* Move the Cumulattive TSN Ack ahead. */
+	sctp_tsnmap_skip(&ulpq->asoc->peer.tsn_map, ftsn);
+	/* purge the fragmentation queue */
+	sctp_intl_reasm_flushtsn(ulpq, ftsn);
+	/* abort only when it's for all data */
+	if (ftsn == sctp_tsnmap_get_max_tsn_seen(&ulpq->asoc->peer.tsn_map))
+		sctp_intl_abort_pd(ulpq, GFP_ATOMIC);
+}
+
+static void sctp_handle_fwdtsn(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk)
+{
+	struct sctp_fwdtsn_skip *skip;
+
+	/* Walk through all the skipped SSNs */
+	sctp_walk_fwdtsn(skip, chunk)
+		sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
+}
+
+static void sctp_intl_skip(struct sctp_ulpq *ulpq, __u16 sid, __u32 mid,
+			   __u8 flags)
+{
+	struct sctp_stream_in *sin = sctp_stream_in(&ulpq->asoc->stream, sid);
+	struct sctp_stream *stream  = &ulpq->asoc->stream;
+
+	if (flags & SCTP_FTSN_U_BIT) {
+		if (sin->pd_mode_uo && MID_lt(sin->mid_uo, mid)) {
+			sin->pd_mode_uo = 0;
+			sctp_intl_stream_abort_pd(ulpq, sid, mid, 0x1,
+						  GFP_ATOMIC);
+		}
+		return;
+	}
+
+	if (MID_lt(mid, sctp_mid_peek(stream, in, sid)))
+		return;
+
+	if (sin->pd_mode) {
+		sin->pd_mode = 0;
+		sctp_intl_stream_abort_pd(ulpq, sid, mid, 0x0, GFP_ATOMIC);
+	}
+
+	sctp_mid_skip(stream, in, sid, mid);
+
+	sctp_intl_reap_ordered(ulpq, sid);
+}
+
+static void sctp_handle_iftsn(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk)
+{
+	struct sctp_ifwdtsn_skip *skip;
+
+	/* Walk through all the skipped MIDs and abort stream pd if possible */
+	sctp_walk_ifwdtsn(skip, chunk)
+		sctp_intl_skip(ulpq, ntohs(skip->stream),
+			       ntohl(skip->mid), skip->flags);
+}
+
+static int do_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
+{
+	struct sk_buff_head temp;
+
+	skb_queue_head_init(&temp);
+	__skb_queue_tail(&temp, sctp_event2skb(event));
+	return sctp_ulpq_tail_event(ulpq, &temp);
+}
+
+static struct sctp_stream_interleave sctp_stream_interleave_0 = {
+	.data_chunk_len		= sizeof(struct sctp_data_chunk),
+	.ftsn_chunk_len		= sizeof(struct sctp_fwdtsn_chunk),
+	/* DATA process functions */
+	.make_datafrag		= sctp_make_datafrag_empty,
+	.assign_number		= sctp_chunk_assign_ssn,
+	.validate_data		= sctp_validate_data,
+	.ulpevent_data		= sctp_ulpq_tail_data,
+	.enqueue_event		= do_ulpq_tail_event,
+	.renege_events		= sctp_ulpq_renege,
+	.start_pd		= sctp_ulpq_partial_delivery,
+	.abort_pd		= sctp_ulpq_abort_pd,
+	/* FORWARD-TSN process functions */
+	.generate_ftsn		= sctp_generate_fwdtsn,
+	.validate_ftsn		= sctp_validate_fwdtsn,
+	.report_ftsn		= sctp_report_fwdtsn,
+	.handle_ftsn		= sctp_handle_fwdtsn,
+};
+
+static int do_sctp_enqueue_event(struct sctp_ulpq *ulpq,
+				 struct sctp_ulpevent *event)
+{
+	struct sk_buff_head temp;
+
+	skb_queue_head_init(&temp);
+	__skb_queue_tail(&temp, sctp_event2skb(event));
+	return sctp_enqueue_event(ulpq, &temp);
+}
+
+static struct sctp_stream_interleave sctp_stream_interleave_1 = {
+	.data_chunk_len		= sizeof(struct sctp_idata_chunk),
+	.ftsn_chunk_len		= sizeof(struct sctp_ifwdtsn_chunk),
+	/* I-DATA process functions */
+	.make_datafrag		= sctp_make_idatafrag_empty,
+	.assign_number		= sctp_chunk_assign_mid,
+	.validate_data		= sctp_validate_idata,
+	.ulpevent_data		= sctp_ulpevent_idata,
+	.enqueue_event		= do_sctp_enqueue_event,
+	.renege_events		= sctp_renege_events,
+	.start_pd		= sctp_intl_start_pd,
+	.abort_pd		= sctp_intl_abort_pd,
+	/* I-FORWARD-TSN process functions */
+	.generate_ftsn		= sctp_generate_iftsn,
+	.validate_ftsn		= sctp_validate_iftsn,
+	.report_ftsn		= sctp_report_iftsn,
+	.handle_ftsn		= sctp_handle_iftsn,
+};
+
+void sctp_stream_interleave_init(struct sctp_stream *stream)
+{
+	struct sctp_association *asoc;
+
+	asoc = container_of(stream, struct sctp_association, stream);
+	stream->si = asoc->peer.intl_capable ? &sctp_stream_interleave_1
+					     : &sctp_stream_interleave_0;
+}