Commit | Line | Data |
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b97bf3fd PL |
1 | /* |
2 | * net/tipc/msg.c: TIPC message header routines | |
c4307285 | 3 | * |
37e22164 | 4 | * Copyright (c) 2000-2006, 2014, Ericsson AB |
741de3e9 | 5 | * Copyright (c) 2005, 2010-2011, Wind River Systems |
b97bf3fd PL |
6 | * All rights reserved. |
7 | * | |
9ea1fd3c | 8 | * Redistribution and use in source and binary forms, with or without |
b97bf3fd PL |
9 | * modification, are permitted provided that the following conditions are met: |
10 | * | |
9ea1fd3c PL |
11 | * 1. Redistributions of source code must retain the above copyright |
12 | * notice, this list of conditions and the following disclaimer. | |
13 | * 2. Redistributions in binary form must reproduce the above copyright | |
14 | * notice, this list of conditions and the following disclaimer in the | |
15 | * documentation and/or other materials provided with the distribution. | |
16 | * 3. Neither the names of the copyright holders nor the names of its | |
17 | * contributors may be used to endorse or promote products derived from | |
18 | * this software without specific prior written permission. | |
b97bf3fd | 19 | * |
9ea1fd3c PL |
20 | * Alternatively, this software may be distributed under the terms of the |
21 | * GNU General Public License ("GPL") version 2 as published by the Free | |
22 | * Software Foundation. | |
23 | * | |
24 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
25 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | |
28 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
29 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
30 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
31 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
32 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
33 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
b97bf3fd PL |
34 | * POSSIBILITY OF SUCH DAMAGE. |
35 | */ | |
36 | ||
c93d3baa | 37 | #include <net/sock.h> |
b97bf3fd | 38 | #include "core.h" |
b97bf3fd | 39 | #include "msg.h" |
5a379074 JPM |
40 | #include "addr.h" |
41 | #include "name_table.h" | |
b97bf3fd | 42 | |
8db1bae3 JPM |
43 | #define MAX_FORWARD_SIZE 1024 |
44 | ||
4f1688b2 | 45 | static unsigned int align(unsigned int i) |
23461e83 | 46 | { |
4f1688b2 | 47 | return (i + 3) & ~3u; |
23461e83 AS |
48 | } |
49 | ||
859fc7c0 YX |
50 | /** |
51 | * tipc_buf_acquire - creates a TIPC message buffer | |
52 | * @size: message size (including TIPC header) | |
53 | * | |
54 | * Returns a new buffer with data pointers set to the specified size. | |
55 | * | |
56 | * NOTE: Headroom is reserved to allow prepending of a data link header. | |
57 | * There may also be unrequested tailroom present at the buffer's end. | |
58 | */ | |
59 | struct sk_buff *tipc_buf_acquire(u32 size) | |
60 | { | |
61 | struct sk_buff *skb; | |
62 | unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u; | |
63 | ||
64 | skb = alloc_skb_fclone(buf_size, GFP_ATOMIC); | |
65 | if (skb) { | |
66 | skb_reserve(skb, BUF_HEADROOM); | |
67 | skb_put(skb, size); | |
68 | skb->next = NULL; | |
69 | } | |
70 | return skb; | |
71 | } | |
72 | ||
ae8509c4 PG |
73 | void tipc_msg_init(struct tipc_msg *m, u32 user, u32 type, u32 hsize, |
74 | u32 destnode) | |
23461e83 AS |
75 | { |
76 | memset(m, 0, hsize); | |
77 | msg_set_version(m); | |
78 | msg_set_user(m, user); | |
79 | msg_set_hdr_sz(m, hsize); | |
80 | msg_set_size(m, hsize); | |
81 | msg_set_prevnode(m, tipc_own_addr); | |
82 | msg_set_type(m, type); | |
1dd0bd2b JPM |
83 | if (hsize > SHORT_H_SIZE) { |
84 | msg_set_orignode(m, tipc_own_addr); | |
85 | msg_set_destnode(m, destnode); | |
86 | } | |
87 | } | |
88 | ||
89 | struct sk_buff *tipc_msg_create(uint user, uint type, uint hdr_sz, | |
90 | uint data_sz, u32 dnode, u32 onode, | |
91 | u32 dport, u32 oport, int errcode) | |
92 | { | |
93 | struct tipc_msg *msg; | |
94 | struct sk_buff *buf; | |
95 | ||
96 | buf = tipc_buf_acquire(hdr_sz + data_sz); | |
97 | if (unlikely(!buf)) | |
98 | return NULL; | |
99 | ||
100 | msg = buf_msg(buf); | |
101 | tipc_msg_init(msg, user, type, hdr_sz, dnode); | |
102 | msg_set_size(msg, hdr_sz + data_sz); | |
103 | msg_set_prevnode(msg, onode); | |
104 | msg_set_origport(msg, oport); | |
105 | msg_set_destport(msg, dport); | |
106 | msg_set_errcode(msg, errcode); | |
107 | if (hdr_sz > SHORT_H_SIZE) { | |
108 | msg_set_orignode(msg, onode); | |
109 | msg_set_destnode(msg, dnode); | |
110 | } | |
111 | return buf; | |
23461e83 AS |
112 | } |
113 | ||
37e22164 | 114 | /* tipc_buf_append(): Append a buffer to the fragment list of another buffer |
29322d0d JPM |
115 | * @*headbuf: in: NULL for first frag, otherwise value returned from prev call |
116 | * out: set when successful non-complete reassembly, otherwise NULL | |
117 | * @*buf: in: the buffer to append. Always defined | |
b2ad5e5f | 118 | * out: head buf after successful complete reassembly, otherwise NULL |
29322d0d | 119 | * Returns 1 when reassembly complete, otherwise 0 |
37e22164 JPM |
120 | */ |
121 | int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf) | |
122 | { | |
123 | struct sk_buff *head = *headbuf; | |
124 | struct sk_buff *frag = *buf; | |
125 | struct sk_buff *tail; | |
13e9b997 JPM |
126 | struct tipc_msg *msg; |
127 | u32 fragid; | |
37e22164 | 128 | int delta; |
13e9b997 | 129 | bool headstolen; |
37e22164 | 130 | |
13e9b997 JPM |
131 | if (!frag) |
132 | goto err; | |
133 | ||
134 | msg = buf_msg(frag); | |
135 | fragid = msg_type(msg); | |
136 | frag->next = NULL; | |
37e22164 JPM |
137 | skb_pull(frag, msg_hdr_sz(msg)); |
138 | ||
139 | if (fragid == FIRST_FRAGMENT) { | |
13e9b997 JPM |
140 | if (unlikely(head)) |
141 | goto err; | |
142 | if (unlikely(skb_unclone(frag, GFP_ATOMIC))) | |
143 | goto err; | |
37e22164 JPM |
144 | head = *headbuf = frag; |
145 | skb_frag_list_init(head); | |
13e9b997 | 146 | TIPC_SKB_CB(head)->tail = NULL; |
29322d0d | 147 | *buf = NULL; |
37e22164 JPM |
148 | return 0; |
149 | } | |
13e9b997 | 150 | |
37e22164 | 151 | if (!head) |
13e9b997 JPM |
152 | goto err; |
153 | ||
37e22164 JPM |
154 | if (skb_try_coalesce(head, frag, &headstolen, &delta)) { |
155 | kfree_skb_partial(frag, headstolen); | |
156 | } else { | |
13e9b997 | 157 | tail = TIPC_SKB_CB(head)->tail; |
37e22164 JPM |
158 | if (!skb_has_frag_list(head)) |
159 | skb_shinfo(head)->frag_list = frag; | |
160 | else | |
161 | tail->next = frag; | |
162 | head->truesize += frag->truesize; | |
163 | head->data_len += frag->len; | |
164 | head->len += frag->len; | |
165 | TIPC_SKB_CB(head)->tail = frag; | |
166 | } | |
13e9b997 | 167 | |
37e22164 JPM |
168 | if (fragid == LAST_FRAGMENT) { |
169 | *buf = head; | |
170 | TIPC_SKB_CB(head)->tail = NULL; | |
171 | *headbuf = NULL; | |
172 | return 1; | |
173 | } | |
174 | *buf = NULL; | |
175 | return 0; | |
13e9b997 JPM |
176 | |
177 | err: | |
37e22164 JPM |
178 | pr_warn_ratelimited("Unable to build fragment list\n"); |
179 | kfree_skb(*buf); | |
29322d0d JPM |
180 | kfree_skb(*headbuf); |
181 | *buf = *headbuf = NULL; | |
37e22164 JPM |
182 | return 0; |
183 | } | |
4f1688b2 | 184 | |
067608e9 JPM |
185 | |
186 | /** | |
9fbfb8b1 | 187 | * tipc_msg_build - create buffer chain containing specified header and data |
067608e9 | 188 | * @mhdr: Message header, to be prepended to data |
45dcc687 | 189 | * @m: User message |
067608e9 JPM |
190 | * @offset: Posision in iov to start copying from |
191 | * @dsz: Total length of user data | |
192 | * @pktmax: Max packet size that can be used | |
a6ca1094 YX |
193 | * @list: Buffer or chain of buffers to be returned to caller |
194 | * | |
067608e9 JPM |
195 | * Returns message data size or errno: -ENOMEM, -EFAULT |
196 | */ | |
a6ca1094 YX |
197 | int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, int offset, |
198 | int dsz, int pktmax, struct sk_buff_head *list) | |
067608e9 JPM |
199 | { |
200 | int mhsz = msg_hdr_sz(mhdr); | |
201 | int msz = mhsz + dsz; | |
202 | int pktno = 1; | |
203 | int pktsz; | |
204 | int pktrem = pktmax; | |
205 | int drem = dsz; | |
206 | struct tipc_msg pkthdr; | |
a6ca1094 | 207 | struct sk_buff *skb; |
067608e9 JPM |
208 | char *pktpos; |
209 | int rc; | |
a6ca1094 | 210 | |
067608e9 JPM |
211 | msg_set_size(mhdr, msz); |
212 | ||
213 | /* No fragmentation needed? */ | |
214 | if (likely(msz <= pktmax)) { | |
a6ca1094 YX |
215 | skb = tipc_buf_acquire(msz); |
216 | if (unlikely(!skb)) | |
067608e9 | 217 | return -ENOMEM; |
c93d3baa | 218 | skb_orphan(skb); |
a6ca1094 YX |
219 | __skb_queue_tail(list, skb); |
220 | skb_copy_to_linear_data(skb, mhdr, mhsz); | |
221 | pktpos = skb->data + mhsz; | |
c0371da6 | 222 | if (!dsz || !memcpy_fromiovecend(pktpos, m->msg_iter.iov, offset, |
a6ca1094 | 223 | dsz)) |
067608e9 JPM |
224 | return dsz; |
225 | rc = -EFAULT; | |
226 | goto error; | |
227 | } | |
228 | ||
229 | /* Prepare reusable fragment header */ | |
230 | tipc_msg_init(&pkthdr, MSG_FRAGMENTER, FIRST_FRAGMENT, | |
231 | INT_H_SIZE, msg_destnode(mhdr)); | |
232 | msg_set_size(&pkthdr, pktmax); | |
233 | msg_set_fragm_no(&pkthdr, pktno); | |
234 | ||
235 | /* Prepare first fragment */ | |
a6ca1094 YX |
236 | skb = tipc_buf_acquire(pktmax); |
237 | if (!skb) | |
067608e9 | 238 | return -ENOMEM; |
c93d3baa | 239 | skb_orphan(skb); |
a6ca1094 YX |
240 | __skb_queue_tail(list, skb); |
241 | pktpos = skb->data; | |
242 | skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); | |
067608e9 JPM |
243 | pktpos += INT_H_SIZE; |
244 | pktrem -= INT_H_SIZE; | |
a6ca1094 | 245 | skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz); |
067608e9 JPM |
246 | pktpos += mhsz; |
247 | pktrem -= mhsz; | |
248 | ||
249 | do { | |
250 | if (drem < pktrem) | |
251 | pktrem = drem; | |
252 | ||
c0371da6 | 253 | if (memcpy_fromiovecend(pktpos, m->msg_iter.iov, offset, pktrem)) { |
067608e9 JPM |
254 | rc = -EFAULT; |
255 | goto error; | |
256 | } | |
257 | drem -= pktrem; | |
258 | offset += pktrem; | |
259 | ||
260 | if (!drem) | |
261 | break; | |
262 | ||
263 | /* Prepare new fragment: */ | |
264 | if (drem < (pktmax - INT_H_SIZE)) | |
265 | pktsz = drem + INT_H_SIZE; | |
266 | else | |
267 | pktsz = pktmax; | |
a6ca1094 YX |
268 | skb = tipc_buf_acquire(pktsz); |
269 | if (!skb) { | |
067608e9 JPM |
270 | rc = -ENOMEM; |
271 | goto error; | |
272 | } | |
c93d3baa | 273 | skb_orphan(skb); |
a6ca1094 | 274 | __skb_queue_tail(list, skb); |
067608e9 JPM |
275 | msg_set_type(&pkthdr, FRAGMENT); |
276 | msg_set_size(&pkthdr, pktsz); | |
277 | msg_set_fragm_no(&pkthdr, ++pktno); | |
a6ca1094 YX |
278 | skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE); |
279 | pktpos = skb->data + INT_H_SIZE; | |
067608e9 JPM |
280 | pktrem = pktsz - INT_H_SIZE; |
281 | ||
282 | } while (1); | |
a6ca1094 | 283 | msg_set_type(buf_msg(skb), LAST_FRAGMENT); |
067608e9 JPM |
284 | return dsz; |
285 | error: | |
a6ca1094 YX |
286 | __skb_queue_purge(list); |
287 | __skb_queue_head_init(list); | |
067608e9 JPM |
288 | return rc; |
289 | } | |
290 | ||
4f1688b2 JPM |
291 | /** |
292 | * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one | |
58dc55f2 YX |
293 | * @list: the buffer chain of the existing buffer ("bundle") |
294 | * @skb: buffer to be appended | |
4f1688b2 JPM |
295 | * @mtu: max allowable size for the bundle buffer |
296 | * Consumes buffer if successful | |
297 | * Returns true if bundling could be performed, otherwise false | |
298 | */ | |
58dc55f2 | 299 | bool tipc_msg_bundle(struct sk_buff_head *list, struct sk_buff *skb, u32 mtu) |
4f1688b2 | 300 | { |
58dc55f2 YX |
301 | struct sk_buff *bskb = skb_peek_tail(list); |
302 | struct tipc_msg *bmsg = buf_msg(bskb); | |
303 | struct tipc_msg *msg = buf_msg(skb); | |
4f1688b2 JPM |
304 | unsigned int bsz = msg_size(bmsg); |
305 | unsigned int msz = msg_size(msg); | |
306 | u32 start = align(bsz); | |
307 | u32 max = mtu - INT_H_SIZE; | |
308 | u32 pad = start - bsz; | |
309 | ||
310 | if (likely(msg_user(msg) == MSG_FRAGMENTER)) | |
311 | return false; | |
312 | if (unlikely(msg_user(msg) == CHANGEOVER_PROTOCOL)) | |
313 | return false; | |
314 | if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) | |
315 | return false; | |
316 | if (likely(msg_user(bmsg) != MSG_BUNDLER)) | |
317 | return false; | |
58dc55f2 | 318 | if (likely(!TIPC_SKB_CB(bskb)->bundling)) |
4f1688b2 | 319 | return false; |
58dc55f2 | 320 | if (unlikely(skb_tailroom(bskb) < (pad + msz))) |
4f1688b2 JPM |
321 | return false; |
322 | if (unlikely(max < (start + msz))) | |
323 | return false; | |
324 | ||
58dc55f2 YX |
325 | skb_put(bskb, pad + msz); |
326 | skb_copy_to_linear_data_offset(bskb, start, skb->data, msz); | |
4f1688b2 JPM |
327 | msg_set_size(bmsg, start + msz); |
328 | msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1); | |
58dc55f2 | 329 | kfree_skb(skb); |
4f1688b2 JPM |
330 | return true; |
331 | } | |
332 | ||
333 | /** | |
334 | * tipc_msg_make_bundle(): Create bundle buf and append message to its tail | |
58dc55f2 YX |
335 | * @list: the buffer chain |
336 | * @skb: buffer to be appended and replaced | |
337 | * @mtu: max allowable size for the bundle buffer, inclusive header | |
4f1688b2 JPM |
338 | * @dnode: destination node for message. (Not always present in header) |
339 | * Replaces buffer if successful | |
b2ad5e5f | 340 | * Returns true if success, otherwise false |
4f1688b2 | 341 | */ |
58dc55f2 YX |
342 | bool tipc_msg_make_bundle(struct sk_buff_head *list, struct sk_buff *skb, |
343 | u32 mtu, u32 dnode) | |
4f1688b2 | 344 | { |
58dc55f2 | 345 | struct sk_buff *bskb; |
4f1688b2 | 346 | struct tipc_msg *bmsg; |
58dc55f2 | 347 | struct tipc_msg *msg = buf_msg(skb); |
4f1688b2 JPM |
348 | u32 msz = msg_size(msg); |
349 | u32 max = mtu - INT_H_SIZE; | |
350 | ||
351 | if (msg_user(msg) == MSG_FRAGMENTER) | |
352 | return false; | |
353 | if (msg_user(msg) == CHANGEOVER_PROTOCOL) | |
354 | return false; | |
355 | if (msg_user(msg) == BCAST_PROTOCOL) | |
356 | return false; | |
357 | if (msz > (max / 2)) | |
358 | return false; | |
359 | ||
58dc55f2 YX |
360 | bskb = tipc_buf_acquire(max); |
361 | if (!bskb) | |
4f1688b2 JPM |
362 | return false; |
363 | ||
58dc55f2 YX |
364 | skb_trim(bskb, INT_H_SIZE); |
365 | bmsg = buf_msg(bskb); | |
58311d16 | 366 | tipc_msg_init(bmsg, MSG_BUNDLER, 0, INT_H_SIZE, dnode); |
4f1688b2 JPM |
367 | msg_set_seqno(bmsg, msg_seqno(msg)); |
368 | msg_set_ack(bmsg, msg_ack(msg)); | |
369 | msg_set_bcast_ack(bmsg, msg_bcast_ack(msg)); | |
58dc55f2 YX |
370 | TIPC_SKB_CB(bskb)->bundling = true; |
371 | __skb_queue_tail(list, bskb); | |
372 | return tipc_msg_bundle(list, skb, mtu); | |
4f1688b2 | 373 | } |
8db1bae3 JPM |
374 | |
375 | /** | |
376 | * tipc_msg_reverse(): swap source and destination addresses and add error code | |
377 | * @buf: buffer containing message to be reversed | |
378 | * @dnode: return value: node where to send message after reversal | |
379 | * @err: error code to be set in message | |
380 | * Consumes buffer if failure | |
381 | * Returns true if success, otherwise false | |
382 | */ | |
383 | bool tipc_msg_reverse(struct sk_buff *buf, u32 *dnode, int err) | |
384 | { | |
385 | struct tipc_msg *msg = buf_msg(buf); | |
386 | uint imp = msg_importance(msg); | |
387 | struct tipc_msg ohdr; | |
388 | uint rdsz = min_t(uint, msg_data_sz(msg), MAX_FORWARD_SIZE); | |
389 | ||
ac0074ee | 390 | if (skb_linearize(buf)) |
8db1bae3 | 391 | goto exit; |
ac0074ee JPM |
392 | if (msg_dest_droppable(msg)) |
393 | goto exit; | |
394 | if (msg_errcode(msg)) | |
8db1bae3 JPM |
395 | goto exit; |
396 | ||
397 | memcpy(&ohdr, msg, msg_hdr_sz(msg)); | |
ac0074ee JPM |
398 | imp = min_t(uint, imp + 1, TIPC_CRITICAL_IMPORTANCE); |
399 | if (msg_isdata(msg)) | |
400 | msg_set_importance(msg, imp); | |
8db1bae3 JPM |
401 | msg_set_errcode(msg, err); |
402 | msg_set_origport(msg, msg_destport(&ohdr)); | |
403 | msg_set_destport(msg, msg_origport(&ohdr)); | |
404 | msg_set_prevnode(msg, tipc_own_addr); | |
405 | if (!msg_short(msg)) { | |
406 | msg_set_orignode(msg, msg_destnode(&ohdr)); | |
407 | msg_set_destnode(msg, msg_orignode(&ohdr)); | |
408 | } | |
409 | msg_set_size(msg, msg_hdr_sz(msg) + rdsz); | |
410 | skb_trim(buf, msg_size(msg)); | |
411 | skb_orphan(buf); | |
412 | *dnode = msg_orignode(&ohdr); | |
413 | return true; | |
414 | exit: | |
415 | kfree_skb(buf); | |
416 | return false; | |
417 | } | |
5a379074 JPM |
418 | |
419 | /** | |
420 | * tipc_msg_eval: determine fate of message that found no destination | |
421 | * @buf: the buffer containing the message. | |
422 | * @dnode: return value: next-hop node, if message to be forwarded | |
423 | * @err: error code to use, if message to be rejected | |
424 | * | |
425 | * Does not consume buffer | |
426 | * Returns 0 (TIPC_OK) if message ok and we can try again, -TIPC error | |
427 | * code if message to be rejected | |
428 | */ | |
429 | int tipc_msg_eval(struct sk_buff *buf, u32 *dnode) | |
430 | { | |
431 | struct tipc_msg *msg = buf_msg(buf); | |
432 | u32 dport; | |
433 | ||
434 | if (msg_type(msg) != TIPC_NAMED_MSG) | |
435 | return -TIPC_ERR_NO_PORT; | |
436 | if (skb_linearize(buf)) | |
437 | return -TIPC_ERR_NO_NAME; | |
438 | if (msg_data_sz(msg) > MAX_FORWARD_SIZE) | |
439 | return -TIPC_ERR_NO_NAME; | |
440 | if (msg_reroute_cnt(msg) > 0) | |
441 | return -TIPC_ERR_NO_NAME; | |
442 | ||
443 | *dnode = addr_domain(msg_lookup_scope(msg)); | |
444 | dport = tipc_nametbl_translate(msg_nametype(msg), | |
445 | msg_nameinst(msg), | |
446 | dnode); | |
447 | if (!dport) | |
448 | return -TIPC_ERR_NO_NAME; | |
449 | msg_incr_reroute_cnt(msg); | |
450 | msg_set_destnode(msg, *dnode); | |
451 | msg_set_destport(msg, dport); | |
452 | return TIPC_OK; | |
453 | } | |
078bec82 JPM |
454 | |
455 | /* tipc_msg_reassemble() - clone a buffer chain of fragments and | |
456 | * reassemble the clones into one message | |
457 | */ | |
a6ca1094 | 458 | struct sk_buff *tipc_msg_reassemble(struct sk_buff_head *list) |
078bec82 | 459 | { |
a6ca1094 YX |
460 | struct sk_buff *skb; |
461 | struct sk_buff *frag = NULL; | |
078bec82 JPM |
462 | struct sk_buff *head = NULL; |
463 | int hdr_sz; | |
464 | ||
465 | /* Copy header if single buffer */ | |
a6ca1094 YX |
466 | if (skb_queue_len(list) == 1) { |
467 | skb = skb_peek(list); | |
468 | hdr_sz = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb)); | |
469 | return __pskb_copy(skb, hdr_sz, GFP_ATOMIC); | |
078bec82 JPM |
470 | } |
471 | ||
472 | /* Clone all fragments and reassemble */ | |
a6ca1094 YX |
473 | skb_queue_walk(list, skb) { |
474 | frag = skb_clone(skb, GFP_ATOMIC); | |
078bec82 JPM |
475 | if (!frag) |
476 | goto error; | |
477 | frag->next = NULL; | |
478 | if (tipc_buf_append(&head, &frag)) | |
479 | break; | |
480 | if (!head) | |
481 | goto error; | |
078bec82 JPM |
482 | } |
483 | return frag; | |
484 | error: | |
485 | pr_warn("Failed do clone local mcast rcv buffer\n"); | |
486 | kfree_skb(head); | |
487 | return NULL; | |
488 | } |