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-rw-r--r--net/tipc/msg.c710
1 files changed, 710 insertions, 0 deletions
diff --git a/net/tipc/msg.c b/net/tipc/msg.c
new file mode 100644
index 000000000..0ac270444
--- /dev/null
+++ b/net/tipc/msg.c
@@ -0,0 +1,710 @@
+/*
+ * net/tipc/msg.c: TIPC message header routines
+ *
+ * Copyright (c) 2000-2006, 2014-2015, Ericsson AB
+ * Copyright (c) 2005, 2010-2011, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <net/sock.h>
+#include "core.h"
+#include "msg.h"
+#include "addr.h"
+#include "name_table.h"
+
+#define MAX_FORWARD_SIZE 1024
+#define BUF_HEADROOM (LL_MAX_HEADER + 48)
+#define BUF_TAILROOM 16
+
+static unsigned int align(unsigned int i)
+{
+ return (i + 3) & ~3u;
+}
+
+/**
+ * tipc_buf_acquire - creates a TIPC message buffer
+ * @size: message size (including TIPC header)
+ *
+ * Returns a new buffer with data pointers set to the specified size.
+ *
+ * NOTE: Headroom is reserved to allow prepending of a data link header.
+ * There may also be unrequested tailroom present at the buffer's end.
+ */
+struct sk_buff *tipc_buf_acquire(u32 size, gfp_t gfp)
+{
+ struct sk_buff *skb;
+ unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
+
+ skb = alloc_skb_fclone(buf_size, gfp);
+ if (skb) {
+ skb_reserve(skb, BUF_HEADROOM);
+ skb_put(skb, size);
+ skb->next = NULL;
+ }
+ return skb;
+}
+
+void tipc_msg_init(u32 own_node, struct tipc_msg *m, u32 user, u32 type,
+ u32 hsize, u32 dnode)
+{
+ memset(m, 0, hsize);
+ msg_set_version(m);
+ msg_set_user(m, user);
+ msg_set_hdr_sz(m, hsize);
+ msg_set_size(m, hsize);
+ msg_set_prevnode(m, own_node);
+ msg_set_type(m, type);
+ if (hsize > SHORT_H_SIZE) {
+ msg_set_orignode(m, own_node);
+ msg_set_destnode(m, dnode);
+ }
+}
+
+struct sk_buff *tipc_msg_create(uint user, uint type,
+ uint hdr_sz, uint data_sz, u32 dnode,
+ u32 onode, u32 dport, u32 oport, int errcode)
+{
+ struct tipc_msg *msg;
+ struct sk_buff *buf;
+
+ buf = tipc_buf_acquire(hdr_sz + data_sz, GFP_ATOMIC);
+ if (unlikely(!buf))
+ return NULL;
+
+ msg = buf_msg(buf);
+ tipc_msg_init(onode, msg, user, type, hdr_sz, dnode);
+ msg_set_size(msg, hdr_sz + data_sz);
+ msg_set_origport(msg, oport);
+ msg_set_destport(msg, dport);
+ msg_set_errcode(msg, errcode);
+ if (hdr_sz > SHORT_H_SIZE) {
+ msg_set_orignode(msg, onode);
+ msg_set_destnode(msg, dnode);
+ }
+ return buf;
+}
+
+/* tipc_buf_append(): Append a buffer to the fragment list of another buffer
+ * @*headbuf: in: NULL for first frag, otherwise value returned from prev call
+ * out: set when successful non-complete reassembly, otherwise NULL
+ * @*buf: in: the buffer to append. Always defined
+ * out: head buf after successful complete reassembly, otherwise NULL
+ * Returns 1 when reassembly complete, otherwise 0
+ */
+int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
+{
+ struct sk_buff *head = *headbuf;
+ struct sk_buff *frag = *buf;
+ struct sk_buff *tail = NULL;
+ struct tipc_msg *msg;
+ u32 fragid;
+ int delta;
+ bool headstolen;
+
+ if (!frag)
+ goto err;
+
+ msg = buf_msg(frag);
+ fragid = msg_type(msg);
+ frag->next = NULL;
+ skb_pull(frag, msg_hdr_sz(msg));
+
+ if (fragid == FIRST_FRAGMENT) {
+ if (unlikely(head))
+ goto err;
+ *buf = NULL;
+ if (skb_has_frag_list(frag) && __skb_linearize(frag))
+ goto err;
+ frag = skb_unshare(frag, GFP_ATOMIC);
+ if (unlikely(!frag))
+ goto err;
+ head = *headbuf = frag;
+ TIPC_SKB_CB(head)->tail = NULL;
+ return 0;
+ }
+
+ if (!head)
+ goto err;
+
+ if (skb_try_coalesce(head, frag, &headstolen, &delta)) {
+ kfree_skb_partial(frag, headstolen);
+ } else {
+ tail = TIPC_SKB_CB(head)->tail;
+ if (!skb_has_frag_list(head))
+ skb_shinfo(head)->frag_list = frag;
+ else
+ tail->next = frag;
+ head->truesize += frag->truesize;
+ head->data_len += frag->len;
+ head->len += frag->len;
+ TIPC_SKB_CB(head)->tail = frag;
+ }
+
+ if (fragid == LAST_FRAGMENT) {
+ TIPC_SKB_CB(head)->validated = false;
+ if (unlikely(!tipc_msg_validate(&head)))
+ goto err;
+ *buf = head;
+ TIPC_SKB_CB(head)->tail = NULL;
+ *headbuf = NULL;
+ return 1;
+ }
+ *buf = NULL;
+ return 0;
+err:
+ kfree_skb(*buf);
+ kfree_skb(*headbuf);
+ *buf = *headbuf = NULL;
+ return 0;
+}
+
+/* tipc_msg_validate - validate basic format of received message
+ *
+ * This routine ensures a TIPC message has an acceptable header, and at least
+ * as much data as the header indicates it should. The routine also ensures
+ * that the entire message header is stored in the main fragment of the message
+ * buffer, to simplify future access to message header fields.
+ *
+ * Note: Having extra info present in the message header or data areas is OK.
+ * TIPC will ignore the excess, under the assumption that it is optional info
+ * introduced by a later release of the protocol.
+ */
+bool tipc_msg_validate(struct sk_buff **_skb)
+{
+ struct sk_buff *skb = *_skb;
+ struct tipc_msg *hdr;
+ int msz, hsz;
+
+ /* Ensure that flow control ratio condition is satisfied */
+ if (unlikely(skb->truesize / buf_roundup_len(skb) >= 4)) {
+ skb = skb_copy_expand(skb, BUF_HEADROOM, 0, GFP_ATOMIC);
+ if (!skb)
+ return false;
+ kfree_skb(*_skb);
+ *_skb = skb;
+ }
+
+ if (unlikely(TIPC_SKB_CB(skb)->validated))
+ return true;
+ if (unlikely(!pskb_may_pull(skb, MIN_H_SIZE)))
+ return false;
+
+ hsz = msg_hdr_sz(buf_msg(skb));
+ if (unlikely(hsz < MIN_H_SIZE) || (hsz > MAX_H_SIZE))
+ return false;
+ if (unlikely(!pskb_may_pull(skb, hsz)))
+ return false;
+
+ hdr = buf_msg(skb);
+ if (unlikely(msg_version(hdr) != TIPC_VERSION))
+ return false;
+
+ msz = msg_size(hdr);
+ if (unlikely(msz < hsz))
+ return false;
+ if (unlikely((msz - hsz) > TIPC_MAX_USER_MSG_SIZE))
+ return false;
+ if (unlikely(skb->len < msz))
+ return false;
+
+ TIPC_SKB_CB(skb)->validated = true;
+ return true;
+}
+
+/**
+ * tipc_msg_build - create buffer chain containing specified header and data
+ * @mhdr: Message header, to be prepended to data
+ * @m: User message
+ * @dsz: Total length of user data
+ * @pktmax: Max packet size that can be used
+ * @list: Buffer or chain of buffers to be returned to caller
+ *
+ * Note that the recursive call we are making here is safe, since it can
+ * logically go only one further level down.
+ *
+ * Returns message data size or errno: -ENOMEM, -EFAULT
+ */
+int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, int offset,
+ int dsz, int pktmax, struct sk_buff_head *list)
+{
+ int mhsz = msg_hdr_sz(mhdr);
+ struct tipc_msg pkthdr;
+ int msz = mhsz + dsz;
+ int pktrem = pktmax;
+ struct sk_buff *skb;
+ int drem = dsz;
+ int pktno = 1;
+ char *pktpos;
+ int pktsz;
+ int rc;
+
+ msg_set_size(mhdr, msz);
+
+ /* No fragmentation needed? */
+ if (likely(msz <= pktmax)) {
+ skb = tipc_buf_acquire(msz, GFP_KERNEL);
+
+ /* Fall back to smaller MTU if node local message */
+ if (unlikely(!skb)) {
+ if (pktmax != MAX_MSG_SIZE)
+ return -ENOMEM;
+ rc = tipc_msg_build(mhdr, m, offset, dsz, FB_MTU, list);
+ if (rc != dsz)
+ return rc;
+ if (tipc_msg_assemble(list))
+ return dsz;
+ return -ENOMEM;
+ }
+ skb_orphan(skb);
+ __skb_queue_tail(list, skb);
+ skb_copy_to_linear_data(skb, mhdr, mhsz);
+ pktpos = skb->data + mhsz;
+ if (copy_from_iter_full(pktpos, dsz, &m->msg_iter))
+ return dsz;
+ rc = -EFAULT;
+ goto error;
+ }
+
+ /* Prepare reusable fragment header */
+ tipc_msg_init(msg_prevnode(mhdr), &pkthdr, MSG_FRAGMENTER,
+ FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(mhdr));
+ msg_set_size(&pkthdr, pktmax);
+ msg_set_fragm_no(&pkthdr, pktno);
+ msg_set_importance(&pkthdr, msg_importance(mhdr));
+
+ /* Prepare first fragment */
+ skb = tipc_buf_acquire(pktmax, GFP_KERNEL);
+ if (!skb)
+ return -ENOMEM;
+ skb_orphan(skb);
+ __skb_queue_tail(list, skb);
+ pktpos = skb->data;
+ skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
+ pktpos += INT_H_SIZE;
+ pktrem -= INT_H_SIZE;
+ skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz);
+ pktpos += mhsz;
+ pktrem -= mhsz;
+
+ do {
+ if (drem < pktrem)
+ pktrem = drem;
+
+ if (!copy_from_iter_full(pktpos, pktrem, &m->msg_iter)) {
+ rc = -EFAULT;
+ goto error;
+ }
+ drem -= pktrem;
+
+ if (!drem)
+ break;
+
+ /* Prepare new fragment: */
+ if (drem < (pktmax - INT_H_SIZE))
+ pktsz = drem + INT_H_SIZE;
+ else
+ pktsz = pktmax;
+ skb = tipc_buf_acquire(pktsz, GFP_KERNEL);
+ if (!skb) {
+ rc = -ENOMEM;
+ goto error;
+ }
+ skb_orphan(skb);
+ __skb_queue_tail(list, skb);
+ msg_set_type(&pkthdr, FRAGMENT);
+ msg_set_size(&pkthdr, pktsz);
+ msg_set_fragm_no(&pkthdr, ++pktno);
+ skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
+ pktpos = skb->data + INT_H_SIZE;
+ pktrem = pktsz - INT_H_SIZE;
+
+ } while (1);
+ msg_set_type(buf_msg(skb), LAST_FRAGMENT);
+ return dsz;
+error:
+ __skb_queue_purge(list);
+ __skb_queue_head_init(list);
+ return rc;
+}
+
+/**
+ * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one
+ * @skb: the buffer to append to ("bundle")
+ * @msg: message to be appended
+ * @mtu: max allowable size for the bundle buffer
+ * Consumes buffer if successful
+ * Returns true if bundling could be performed, otherwise false
+ */
+bool tipc_msg_bundle(struct sk_buff *skb, struct tipc_msg *msg, u32 mtu)
+{
+ struct tipc_msg *bmsg;
+ unsigned int bsz;
+ unsigned int msz = msg_size(msg);
+ u32 start, pad;
+ u32 max = mtu - INT_H_SIZE;
+
+ if (likely(msg_user(msg) == MSG_FRAGMENTER))
+ return false;
+ if (!skb)
+ return false;
+ bmsg = buf_msg(skb);
+ bsz = msg_size(bmsg);
+ start = align(bsz);
+ pad = start - bsz;
+
+ if (unlikely(msg_user(msg) == TUNNEL_PROTOCOL))
+ return false;
+ if (unlikely(msg_user(msg) == BCAST_PROTOCOL))
+ return false;
+ if (unlikely(msg_user(bmsg) != MSG_BUNDLER))
+ return false;
+ if (unlikely(skb_tailroom(skb) < (pad + msz)))
+ return false;
+ if (unlikely(max < (start + msz)))
+ return false;
+ if ((msg_importance(msg) < TIPC_SYSTEM_IMPORTANCE) &&
+ (msg_importance(bmsg) == TIPC_SYSTEM_IMPORTANCE))
+ return false;
+
+ skb_put(skb, pad + msz);
+ skb_copy_to_linear_data_offset(skb, start, msg, msz);
+ msg_set_size(bmsg, start + msz);
+ msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1);
+ return true;
+}
+
+/**
+ * tipc_msg_extract(): extract bundled inner packet from buffer
+ * @skb: buffer to be extracted from.
+ * @iskb: extracted inner buffer, to be returned
+ * @pos: position in outer message of msg to be extracted.
+ * Returns position of next msg
+ * Consumes outer buffer when last packet extracted
+ * Returns true when when there is an extracted buffer, otherwise false
+ */
+bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos)
+{
+ struct tipc_msg *hdr, *ihdr;
+ int imsz;
+
+ *iskb = NULL;
+ if (unlikely(skb_linearize(skb)))
+ goto none;
+
+ hdr = buf_msg(skb);
+ if (unlikely(*pos > (msg_data_sz(hdr) - MIN_H_SIZE)))
+ goto none;
+
+ ihdr = (struct tipc_msg *)(msg_data(hdr) + *pos);
+ imsz = msg_size(ihdr);
+
+ if ((*pos + imsz) > msg_data_sz(hdr))
+ goto none;
+
+ *iskb = tipc_buf_acquire(imsz, GFP_ATOMIC);
+ if (!*iskb)
+ goto none;
+
+ skb_copy_to_linear_data(*iskb, ihdr, imsz);
+ if (unlikely(!tipc_msg_validate(iskb)))
+ goto none;
+
+ *pos += align(imsz);
+ return true;
+none:
+ kfree_skb(skb);
+ kfree_skb(*iskb);
+ *iskb = NULL;
+ return false;
+}
+
+/**
+ * tipc_msg_make_bundle(): Create bundle buf and append message to its tail
+ * @list: the buffer chain, where head is the buffer to replace/append
+ * @skb: buffer to be created, appended to and returned in case of success
+ * @msg: message to be appended
+ * @mtu: max allowable size for the bundle buffer, inclusive header
+ * @dnode: destination node for message. (Not always present in header)
+ * Returns true if success, otherwise false
+ */
+bool tipc_msg_make_bundle(struct sk_buff **skb, struct tipc_msg *msg,
+ u32 mtu, u32 dnode)
+{
+ struct sk_buff *_skb;
+ struct tipc_msg *bmsg;
+ u32 msz = msg_size(msg);
+ u32 max = mtu - INT_H_SIZE;
+
+ if (msg_user(msg) == MSG_FRAGMENTER)
+ return false;
+ if (msg_user(msg) == TUNNEL_PROTOCOL)
+ return false;
+ if (msg_user(msg) == BCAST_PROTOCOL)
+ return false;
+ if (msz > (max / 2))
+ return false;
+
+ _skb = tipc_buf_acquire(max, GFP_ATOMIC);
+ if (!_skb)
+ return false;
+
+ skb_trim(_skb, INT_H_SIZE);
+ bmsg = buf_msg(_skb);
+ tipc_msg_init(msg_prevnode(msg), bmsg, MSG_BUNDLER, 0,
+ INT_H_SIZE, dnode);
+ msg_set_importance(bmsg, msg_importance(msg));
+ msg_set_seqno(bmsg, msg_seqno(msg));
+ msg_set_ack(bmsg, msg_ack(msg));
+ msg_set_bcast_ack(bmsg, msg_bcast_ack(msg));
+ tipc_msg_bundle(_skb, msg, mtu);
+ *skb = _skb;
+ return true;
+}
+
+/**
+ * tipc_msg_reverse(): swap source and destination addresses and add error code
+ * @own_node: originating node id for reversed message
+ * @skb: buffer containing message to be reversed; may be replaced.
+ * @err: error code to be set in message, if any
+ * Consumes buffer at failure
+ * Returns true if success, otherwise false
+ */
+bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err)
+{
+ struct sk_buff *_skb = *skb;
+ struct tipc_msg *hdr;
+ struct tipc_msg ohdr;
+ int dlen;
+
+ if (skb_linearize(_skb))
+ goto exit;
+ hdr = buf_msg(_skb);
+ dlen = min_t(uint, msg_data_sz(hdr), MAX_FORWARD_SIZE);
+ if (msg_dest_droppable(hdr))
+ goto exit;
+ if (msg_errcode(hdr))
+ goto exit;
+
+ /* Take a copy of original header before altering message */
+ memcpy(&ohdr, hdr, msg_hdr_sz(hdr));
+
+ /* Never return SHORT header; expand by replacing buffer if necessary */
+ if (msg_short(hdr)) {
+ *skb = tipc_buf_acquire(BASIC_H_SIZE + dlen, GFP_ATOMIC);
+ if (!*skb)
+ goto exit;
+ memcpy((*skb)->data + BASIC_H_SIZE, msg_data(hdr), dlen);
+ kfree_skb(_skb);
+ _skb = *skb;
+ hdr = buf_msg(_skb);
+ memcpy(hdr, &ohdr, BASIC_H_SIZE);
+ msg_set_hdr_sz(hdr, BASIC_H_SIZE);
+ }
+
+ /* Now reverse the concerned fields */
+ msg_set_errcode(hdr, err);
+ msg_set_non_seq(hdr, 0);
+ msg_set_origport(hdr, msg_destport(&ohdr));
+ msg_set_destport(hdr, msg_origport(&ohdr));
+ msg_set_destnode(hdr, msg_prevnode(&ohdr));
+ msg_set_prevnode(hdr, own_node);
+ msg_set_orignode(hdr, own_node);
+ msg_set_size(hdr, msg_hdr_sz(hdr) + dlen);
+ skb_trim(_skb, msg_size(hdr));
+ skb_orphan(_skb);
+ return true;
+exit:
+ kfree_skb(_skb);
+ *skb = NULL;
+ return false;
+}
+
+/**
+ * tipc_msg_lookup_dest(): try to find new destination for named message
+ * @skb: the buffer containing the message.
+ * @err: error code to be used by caller if lookup fails
+ * Does not consume buffer
+ * Returns true if a destination is found, false otherwise
+ */
+bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err)
+{
+ struct tipc_msg *msg = buf_msg(skb);
+ u32 dport, dnode;
+ u32 onode = tipc_own_addr(net);
+
+ if (!msg_isdata(msg))
+ return false;
+ if (!msg_named(msg))
+ return false;
+ if (msg_errcode(msg))
+ return false;
+ *err = TIPC_ERR_NO_NAME;
+ if (skb_linearize(skb))
+ return false;
+ msg = buf_msg(skb);
+ if (msg_reroute_cnt(msg))
+ return false;
+ dnode = tipc_scope2node(net, msg_lookup_scope(msg));
+ dport = tipc_nametbl_translate(net, msg_nametype(msg),
+ msg_nameinst(msg), &dnode);
+ if (!dport)
+ return false;
+ msg_incr_reroute_cnt(msg);
+ if (dnode != onode)
+ msg_set_prevnode(msg, onode);
+ msg_set_destnode(msg, dnode);
+ msg_set_destport(msg, dport);
+ *err = TIPC_OK;
+
+ if (!skb_cloned(skb))
+ return true;
+
+ return true;
+}
+
+/* tipc_msg_assemble() - assemble chain of fragments into one message
+ */
+bool tipc_msg_assemble(struct sk_buff_head *list)
+{
+ struct sk_buff *skb, *tmp = NULL;
+
+ if (skb_queue_len(list) == 1)
+ return true;
+
+ while ((skb = __skb_dequeue(list))) {
+ skb->next = NULL;
+ if (tipc_buf_append(&tmp, &skb)) {
+ __skb_queue_tail(list, skb);
+ return true;
+ }
+ if (!tmp)
+ break;
+ }
+ __skb_queue_purge(list);
+ __skb_queue_head_init(list);
+ pr_warn("Failed do assemble buffer\n");
+ return false;
+}
+
+/* tipc_msg_reassemble() - clone a buffer chain of fragments and
+ * reassemble the clones into one message
+ */
+bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq)
+{
+ struct sk_buff *skb, *_skb;
+ struct sk_buff *frag = NULL;
+ struct sk_buff *head = NULL;
+ int hdr_len;
+
+ /* Copy header if single buffer */
+ if (skb_queue_len(list) == 1) {
+ skb = skb_peek(list);
+ hdr_len = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb));
+ _skb = __pskb_copy(skb, hdr_len, GFP_ATOMIC);
+ if (!_skb)
+ return false;
+ __skb_queue_tail(rcvq, _skb);
+ return true;
+ }
+
+ /* Clone all fragments and reassemble */
+ skb_queue_walk(list, skb) {
+ frag = skb_clone(skb, GFP_ATOMIC);
+ if (!frag)
+ goto error;
+ frag->next = NULL;
+ if (tipc_buf_append(&head, &frag))
+ break;
+ if (!head)
+ goto error;
+ }
+ __skb_queue_tail(rcvq, frag);
+ return true;
+error:
+ pr_warn("Failed do clone local mcast rcv buffer\n");
+ kfree_skb(head);
+ return false;
+}
+
+bool tipc_msg_pskb_copy(u32 dst, struct sk_buff_head *msg,
+ struct sk_buff_head *cpy)
+{
+ struct sk_buff *skb, *_skb;
+
+ skb_queue_walk(msg, skb) {
+ _skb = pskb_copy(skb, GFP_ATOMIC);
+ if (!_skb) {
+ __skb_queue_purge(cpy);
+ return false;
+ }
+ msg_set_destnode(buf_msg(_skb), dst);
+ __skb_queue_tail(cpy, _skb);
+ }
+ return true;
+}
+
+/* tipc_skb_queue_sorted(); sort pkt into list according to sequence number
+ * @list: list to be appended to
+ * @seqno: sequence number of buffer to add
+ * @skb: buffer to add
+ */
+void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno,
+ struct sk_buff *skb)
+{
+ struct sk_buff *_skb, *tmp;
+
+ if (skb_queue_empty(list) || less(seqno, buf_seqno(skb_peek(list)))) {
+ __skb_queue_head(list, skb);
+ return;
+ }
+
+ if (more(seqno, buf_seqno(skb_peek_tail(list)))) {
+ __skb_queue_tail(list, skb);
+ return;
+ }
+
+ skb_queue_walk_safe(list, _skb, tmp) {
+ if (more(seqno, buf_seqno(_skb)))
+ continue;
+ if (seqno == buf_seqno(_skb))
+ break;
+ __skb_queue_before(list, _skb, skb);
+ return;
+ }
+ kfree_skb(skb);
+}
+
+void tipc_skb_reject(struct net *net, int err, struct sk_buff *skb,
+ struct sk_buff_head *xmitq)
+{
+ if (tipc_msg_reverse(tipc_own_addr(net), &skb, err))
+ __skb_queue_tail(xmitq, skb);
+}