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604326b4 DB |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */ | |
3 | ||
4 | #include <linux/skmsg.h> | |
5 | #include <linux/skbuff.h> | |
6 | #include <linux/scatterlist.h> | |
7 | ||
8 | #include <net/sock.h> | |
9 | #include <net/tcp.h> | |
10 | ||
11 | static bool sk_msg_try_coalesce_ok(struct sk_msg *msg, int elem_first_coalesce) | |
12 | { | |
13 | if (msg->sg.end > msg->sg.start && | |
14 | elem_first_coalesce < msg->sg.end) | |
15 | return true; | |
16 | ||
17 | if (msg->sg.end < msg->sg.start && | |
18 | (elem_first_coalesce > msg->sg.start || | |
19 | elem_first_coalesce < msg->sg.end)) | |
20 | return true; | |
21 | ||
22 | return false; | |
23 | } | |
24 | ||
25 | int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len, | |
26 | int elem_first_coalesce) | |
27 | { | |
28 | struct page_frag *pfrag = sk_page_frag(sk); | |
29 | int ret = 0; | |
30 | ||
31 | len -= msg->sg.size; | |
32 | while (len > 0) { | |
33 | struct scatterlist *sge; | |
34 | u32 orig_offset; | |
35 | int use, i; | |
36 | ||
37 | if (!sk_page_frag_refill(sk, pfrag)) | |
38 | return -ENOMEM; | |
39 | ||
40 | orig_offset = pfrag->offset; | |
41 | use = min_t(int, len, pfrag->size - orig_offset); | |
42 | if (!sk_wmem_schedule(sk, use)) | |
43 | return -ENOMEM; | |
44 | ||
45 | i = msg->sg.end; | |
46 | sk_msg_iter_var_prev(i); | |
47 | sge = &msg->sg.data[i]; | |
48 | ||
49 | if (sk_msg_try_coalesce_ok(msg, elem_first_coalesce) && | |
50 | sg_page(sge) == pfrag->page && | |
51 | sge->offset + sge->length == orig_offset) { | |
52 | sge->length += use; | |
53 | } else { | |
54 | if (sk_msg_full(msg)) { | |
55 | ret = -ENOSPC; | |
56 | break; | |
57 | } | |
58 | ||
59 | sge = &msg->sg.data[msg->sg.end]; | |
60 | sg_unmark_end(sge); | |
61 | sg_set_page(sge, pfrag->page, use, orig_offset); | |
62 | get_page(pfrag->page); | |
63 | sk_msg_iter_next(msg, end); | |
64 | } | |
65 | ||
66 | sk_mem_charge(sk, use); | |
67 | msg->sg.size += use; | |
68 | pfrag->offset += use; | |
69 | len -= use; | |
70 | } | |
71 | ||
72 | return ret; | |
73 | } | |
74 | EXPORT_SYMBOL_GPL(sk_msg_alloc); | |
75 | ||
d829e9c4 DB |
76 | int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src, |
77 | u32 off, u32 len) | |
78 | { | |
79 | int i = src->sg.start; | |
80 | struct scatterlist *sge = sk_msg_elem(src, i); | |
fda497e5 | 81 | struct scatterlist *sgd = NULL; |
d829e9c4 DB |
82 | u32 sge_len, sge_off; |
83 | ||
d829e9c4 DB |
84 | while (off) { |
85 | if (sge->length > off) | |
86 | break; | |
87 | off -= sge->length; | |
88 | sk_msg_iter_var_next(i); | |
89 | if (i == src->sg.end && off) | |
90 | return -ENOSPC; | |
91 | sge = sk_msg_elem(src, i); | |
92 | } | |
93 | ||
94 | while (len) { | |
95 | sge_len = sge->length - off; | |
d829e9c4 DB |
96 | if (sge_len > len) |
97 | sge_len = len; | |
fda497e5 VG |
98 | |
99 | if (dst->sg.end) | |
100 | sgd = sk_msg_elem(dst, dst->sg.end - 1); | |
101 | ||
102 | if (sgd && | |
103 | (sg_page(sge) == sg_page(sgd)) && | |
104 | (sg_virt(sge) + off == sg_virt(sgd) + sgd->length)) { | |
105 | sgd->length += sge_len; | |
106 | dst->sg.size += sge_len; | |
107 | } else if (!sk_msg_full(dst)) { | |
108 | sge_off = sge->offset + off; | |
109 | sk_msg_page_add(dst, sg_page(sge), sge_len, sge_off); | |
110 | } else { | |
111 | return -ENOSPC; | |
112 | } | |
113 | ||
d829e9c4 DB |
114 | off = 0; |
115 | len -= sge_len; | |
d829e9c4 DB |
116 | sk_mem_charge(sk, sge_len); |
117 | sk_msg_iter_var_next(i); | |
118 | if (i == src->sg.end && len) | |
119 | return -ENOSPC; | |
120 | sge = sk_msg_elem(src, i); | |
121 | } | |
122 | ||
123 | return 0; | |
124 | } | |
125 | EXPORT_SYMBOL_GPL(sk_msg_clone); | |
126 | ||
604326b4 DB |
127 | void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes) |
128 | { | |
129 | int i = msg->sg.start; | |
130 | ||
131 | do { | |
132 | struct scatterlist *sge = sk_msg_elem(msg, i); | |
133 | ||
134 | if (bytes < sge->length) { | |
135 | sge->length -= bytes; | |
136 | sge->offset += bytes; | |
137 | sk_mem_uncharge(sk, bytes); | |
138 | break; | |
139 | } | |
140 | ||
141 | sk_mem_uncharge(sk, sge->length); | |
142 | bytes -= sge->length; | |
143 | sge->length = 0; | |
144 | sge->offset = 0; | |
145 | sk_msg_iter_var_next(i); | |
146 | } while (bytes && i != msg->sg.end); | |
147 | msg->sg.start = i; | |
148 | } | |
149 | EXPORT_SYMBOL_GPL(sk_msg_return_zero); | |
150 | ||
151 | void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes) | |
152 | { | |
153 | int i = msg->sg.start; | |
154 | ||
155 | do { | |
156 | struct scatterlist *sge = &msg->sg.data[i]; | |
157 | int uncharge = (bytes < sge->length) ? bytes : sge->length; | |
158 | ||
159 | sk_mem_uncharge(sk, uncharge); | |
160 | bytes -= uncharge; | |
161 | sk_msg_iter_var_next(i); | |
162 | } while (i != msg->sg.end); | |
163 | } | |
164 | EXPORT_SYMBOL_GPL(sk_msg_return); | |
165 | ||
166 | static int sk_msg_free_elem(struct sock *sk, struct sk_msg *msg, u32 i, | |
167 | bool charge) | |
168 | { | |
169 | struct scatterlist *sge = sk_msg_elem(msg, i); | |
170 | u32 len = sge->length; | |
171 | ||
172 | if (charge) | |
173 | sk_mem_uncharge(sk, len); | |
174 | if (!msg->skb) | |
175 | put_page(sg_page(sge)); | |
176 | memset(sge, 0, sizeof(*sge)); | |
177 | return len; | |
178 | } | |
179 | ||
180 | static int __sk_msg_free(struct sock *sk, struct sk_msg *msg, u32 i, | |
181 | bool charge) | |
182 | { | |
183 | struct scatterlist *sge = sk_msg_elem(msg, i); | |
184 | int freed = 0; | |
185 | ||
186 | while (msg->sg.size) { | |
187 | msg->sg.size -= sge->length; | |
188 | freed += sk_msg_free_elem(sk, msg, i, charge); | |
189 | sk_msg_iter_var_next(i); | |
190 | sk_msg_check_to_free(msg, i, msg->sg.size); | |
191 | sge = sk_msg_elem(msg, i); | |
192 | } | |
dd016aca | 193 | consume_skb(msg->skb); |
604326b4 DB |
194 | sk_msg_init(msg); |
195 | return freed; | |
196 | } | |
197 | ||
198 | int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg) | |
199 | { | |
200 | return __sk_msg_free(sk, msg, msg->sg.start, false); | |
201 | } | |
202 | EXPORT_SYMBOL_GPL(sk_msg_free_nocharge); | |
203 | ||
204 | int sk_msg_free(struct sock *sk, struct sk_msg *msg) | |
205 | { | |
206 | return __sk_msg_free(sk, msg, msg->sg.start, true); | |
207 | } | |
208 | EXPORT_SYMBOL_GPL(sk_msg_free); | |
209 | ||
210 | static void __sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, | |
211 | u32 bytes, bool charge) | |
212 | { | |
213 | struct scatterlist *sge; | |
214 | u32 i = msg->sg.start; | |
215 | ||
216 | while (bytes) { | |
217 | sge = sk_msg_elem(msg, i); | |
218 | if (!sge->length) | |
219 | break; | |
220 | if (bytes < sge->length) { | |
221 | if (charge) | |
222 | sk_mem_uncharge(sk, bytes); | |
223 | sge->length -= bytes; | |
224 | sge->offset += bytes; | |
225 | msg->sg.size -= bytes; | |
226 | break; | |
227 | } | |
228 | ||
229 | msg->sg.size -= sge->length; | |
230 | bytes -= sge->length; | |
231 | sk_msg_free_elem(sk, msg, i, charge); | |
232 | sk_msg_iter_var_next(i); | |
233 | sk_msg_check_to_free(msg, i, bytes); | |
234 | } | |
235 | msg->sg.start = i; | |
236 | } | |
237 | ||
238 | void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes) | |
239 | { | |
240 | __sk_msg_free_partial(sk, msg, bytes, true); | |
241 | } | |
242 | EXPORT_SYMBOL_GPL(sk_msg_free_partial); | |
243 | ||
244 | void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg, | |
245 | u32 bytes) | |
246 | { | |
247 | __sk_msg_free_partial(sk, msg, bytes, false); | |
248 | } | |
249 | ||
250 | void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len) | |
251 | { | |
252 | int trim = msg->sg.size - len; | |
253 | u32 i = msg->sg.end; | |
254 | ||
255 | if (trim <= 0) { | |
256 | WARN_ON(trim < 0); | |
257 | return; | |
258 | } | |
259 | ||
260 | sk_msg_iter_var_prev(i); | |
261 | msg->sg.size = len; | |
262 | while (msg->sg.data[i].length && | |
263 | trim >= msg->sg.data[i].length) { | |
264 | trim -= msg->sg.data[i].length; | |
265 | sk_msg_free_elem(sk, msg, i, true); | |
266 | sk_msg_iter_var_prev(i); | |
267 | if (!trim) | |
268 | goto out; | |
269 | } | |
270 | ||
271 | msg->sg.data[i].length -= trim; | |
272 | sk_mem_uncharge(sk, trim); | |
683916f6 JK |
273 | /* Adjust copybreak if it falls into the trimmed part of last buf */ |
274 | if (msg->sg.curr == i && msg->sg.copybreak > msg->sg.data[i].length) | |
275 | msg->sg.copybreak = msg->sg.data[i].length; | |
604326b4 | 276 | out: |
683916f6 JK |
277 | sk_msg_iter_var_next(i); |
278 | msg->sg.end = i; | |
279 | ||
280 | /* If we trim data a full sg elem before curr pointer update | |
281 | * copybreak and current so that any future copy operations | |
282 | * start at new copy location. | |
604326b4 DB |
283 | * However trimed data that has not yet been used in a copy op |
284 | * does not require an update. | |
285 | */ | |
683916f6 JK |
286 | if (!msg->sg.size) { |
287 | msg->sg.curr = msg->sg.start; | |
288 | msg->sg.copybreak = 0; | |
289 | } else if (sk_msg_iter_dist(msg->sg.start, msg->sg.curr) >= | |
290 | sk_msg_iter_dist(msg->sg.start, msg->sg.end)) { | |
291 | sk_msg_iter_var_prev(i); | |
604326b4 DB |
292 | msg->sg.curr = i; |
293 | msg->sg.copybreak = msg->sg.data[i].length; | |
294 | } | |
604326b4 DB |
295 | } |
296 | EXPORT_SYMBOL_GPL(sk_msg_trim); | |
297 | ||
298 | int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from, | |
299 | struct sk_msg *msg, u32 bytes) | |
300 | { | |
301 | int i, maxpages, ret = 0, num_elems = sk_msg_elem_used(msg); | |
302 | const int to_max_pages = MAX_MSG_FRAGS; | |
303 | struct page *pages[MAX_MSG_FRAGS]; | |
304 | ssize_t orig, copied, use, offset; | |
305 | ||
306 | orig = msg->sg.size; | |
307 | while (bytes > 0) { | |
308 | i = 0; | |
309 | maxpages = to_max_pages - num_elems; | |
310 | if (maxpages == 0) { | |
311 | ret = -EFAULT; | |
312 | goto out; | |
313 | } | |
314 | ||
315 | copied = iov_iter_get_pages(from, pages, bytes, maxpages, | |
316 | &offset); | |
317 | if (copied <= 0) { | |
318 | ret = -EFAULT; | |
319 | goto out; | |
320 | } | |
321 | ||
322 | iov_iter_advance(from, copied); | |
323 | bytes -= copied; | |
324 | msg->sg.size += copied; | |
325 | ||
326 | while (copied) { | |
327 | use = min_t(int, copied, PAGE_SIZE - offset); | |
328 | sg_set_page(&msg->sg.data[msg->sg.end], | |
329 | pages[i], use, offset); | |
330 | sg_unmark_end(&msg->sg.data[msg->sg.end]); | |
331 | sk_mem_charge(sk, use); | |
332 | ||
333 | offset = 0; | |
334 | copied -= use; | |
335 | sk_msg_iter_next(msg, end); | |
336 | num_elems++; | |
337 | i++; | |
338 | } | |
339 | /* When zerocopy is mixed with sk_msg_*copy* operations we | |
340 | * may have a copybreak set in this case clear and prefer | |
341 | * zerocopy remainder when possible. | |
342 | */ | |
343 | msg->sg.copybreak = 0; | |
344 | msg->sg.curr = msg->sg.end; | |
345 | } | |
346 | out: | |
347 | /* Revert iov_iter updates, msg will need to use 'trim' later if it | |
348 | * also needs to be cleared. | |
349 | */ | |
350 | if (ret) | |
351 | iov_iter_revert(from, msg->sg.size - orig); | |
352 | return ret; | |
353 | } | |
354 | EXPORT_SYMBOL_GPL(sk_msg_zerocopy_from_iter); | |
355 | ||
356 | int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from, | |
357 | struct sk_msg *msg, u32 bytes) | |
358 | { | |
359 | int ret = -ENOSPC, i = msg->sg.curr; | |
360 | struct scatterlist *sge; | |
361 | u32 copy, buf_size; | |
362 | void *to; | |
363 | ||
364 | do { | |
365 | sge = sk_msg_elem(msg, i); | |
366 | /* This is possible if a trim operation shrunk the buffer */ | |
367 | if (msg->sg.copybreak >= sge->length) { | |
368 | msg->sg.copybreak = 0; | |
369 | sk_msg_iter_var_next(i); | |
370 | if (i == msg->sg.end) | |
371 | break; | |
372 | sge = sk_msg_elem(msg, i); | |
373 | } | |
374 | ||
375 | buf_size = sge->length - msg->sg.copybreak; | |
376 | copy = (buf_size > bytes) ? bytes : buf_size; | |
377 | to = sg_virt(sge) + msg->sg.copybreak; | |
378 | msg->sg.copybreak += copy; | |
379 | if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) | |
380 | ret = copy_from_iter_nocache(to, copy, from); | |
381 | else | |
382 | ret = copy_from_iter(to, copy, from); | |
383 | if (ret != copy) { | |
384 | ret = -EFAULT; | |
385 | goto out; | |
386 | } | |
387 | bytes -= copy; | |
388 | if (!bytes) | |
389 | break; | |
390 | msg->sg.copybreak = 0; | |
391 | sk_msg_iter_var_next(i); | |
392 | } while (i != msg->sg.end); | |
393 | out: | |
394 | msg->sg.curr = i; | |
395 | return ret; | |
396 | } | |
397 | EXPORT_SYMBOL_GPL(sk_msg_memcopy_from_iter); | |
398 | ||
399 | static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb) | |
400 | { | |
401 | struct sock *sk = psock->sk; | |
402 | int copied = 0, num_sge; | |
403 | struct sk_msg *msg; | |
404 | ||
405 | msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_ATOMIC); | |
406 | if (unlikely(!msg)) | |
407 | return -EAGAIN; | |
408 | if (!sk_rmem_schedule(sk, skb, skb->len)) { | |
409 | kfree(msg); | |
410 | return -EAGAIN; | |
411 | } | |
412 | ||
413 | sk_msg_init(msg); | |
414 | num_sge = skb_to_sgvec(skb, msg->sg.data, 0, skb->len); | |
415 | if (unlikely(num_sge < 0)) { | |
416 | kfree(msg); | |
417 | return num_sge; | |
418 | } | |
419 | ||
420 | sk_mem_charge(sk, skb->len); | |
421 | copied = skb->len; | |
422 | msg->sg.start = 0; | |
cabede8b | 423 | msg->sg.size = copied; |
031097d9 | 424 | msg->sg.end = num_sge; |
604326b4 DB |
425 | msg->skb = skb; |
426 | ||
427 | sk_psock_queue_msg(psock, msg); | |
552de910 | 428 | sk_psock_data_ready(sk, psock); |
604326b4 DB |
429 | return copied; |
430 | } | |
431 | ||
432 | static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb, | |
433 | u32 off, u32 len, bool ingress) | |
434 | { | |
435 | if (ingress) | |
436 | return sk_psock_skb_ingress(psock, skb); | |
437 | else | |
438 | return skb_send_sock_locked(psock->sk, skb, off, len); | |
439 | } | |
440 | ||
441 | static void sk_psock_backlog(struct work_struct *work) | |
442 | { | |
443 | struct sk_psock *psock = container_of(work, struct sk_psock, work); | |
444 | struct sk_psock_work_state *state = &psock->work_state; | |
445 | struct sk_buff *skb; | |
446 | bool ingress; | |
447 | u32 len, off; | |
448 | int ret; | |
449 | ||
450 | /* Lock sock to avoid losing sk_socket during loop. */ | |
451 | lock_sock(psock->sk); | |
452 | if (state->skb) { | |
453 | skb = state->skb; | |
454 | len = state->len; | |
455 | off = state->off; | |
456 | state->skb = NULL; | |
457 | goto start; | |
458 | } | |
459 | ||
460 | while ((skb = skb_dequeue(&psock->ingress_skb))) { | |
461 | len = skb->len; | |
462 | off = 0; | |
463 | start: | |
464 | ingress = tcp_skb_bpf_ingress(skb); | |
465 | do { | |
466 | ret = -EIO; | |
467 | if (likely(psock->sk->sk_socket)) | |
468 | ret = sk_psock_handle_skb(psock, skb, off, | |
469 | len, ingress); | |
470 | if (ret <= 0) { | |
471 | if (ret == -EAGAIN) { | |
472 | state->skb = skb; | |
473 | state->len = len; | |
474 | state->off = off; | |
475 | goto end; | |
476 | } | |
477 | /* Hard errors break pipe and stop xmit. */ | |
478 | sk_psock_report_error(psock, ret ? -ret : EPIPE); | |
479 | sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED); | |
480 | kfree_skb(skb); | |
481 | goto end; | |
482 | } | |
483 | off += ret; | |
484 | len -= ret; | |
485 | } while (len); | |
486 | ||
487 | if (!ingress) | |
488 | kfree_skb(skb); | |
489 | } | |
490 | end: | |
491 | release_sock(psock->sk); | |
492 | } | |
493 | ||
494 | struct sk_psock *sk_psock_init(struct sock *sk, int node) | |
495 | { | |
496 | struct sk_psock *psock = kzalloc_node(sizeof(*psock), | |
497 | GFP_ATOMIC | __GFP_NOWARN, | |
498 | node); | |
499 | if (!psock) | |
500 | return NULL; | |
501 | ||
502 | psock->sk = sk; | |
503 | psock->eval = __SK_NONE; | |
504 | ||
505 | INIT_LIST_HEAD(&psock->link); | |
506 | spin_lock_init(&psock->link_lock); | |
507 | ||
508 | INIT_WORK(&psock->work, sk_psock_backlog); | |
509 | INIT_LIST_HEAD(&psock->ingress_msg); | |
510 | skb_queue_head_init(&psock->ingress_skb); | |
511 | ||
512 | sk_psock_set_state(psock, SK_PSOCK_TX_ENABLED); | |
513 | refcount_set(&psock->refcnt, 1); | |
514 | ||
f1ff5ce2 | 515 | rcu_assign_sk_user_data_nocopy(sk, psock); |
604326b4 DB |
516 | sock_hold(sk); |
517 | ||
518 | return psock; | |
519 | } | |
520 | EXPORT_SYMBOL_GPL(sk_psock_init); | |
521 | ||
522 | struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock) | |
523 | { | |
524 | struct sk_psock_link *link; | |
525 | ||
526 | spin_lock_bh(&psock->link_lock); | |
527 | link = list_first_entry_or_null(&psock->link, struct sk_psock_link, | |
528 | list); | |
529 | if (link) | |
530 | list_del(&link->list); | |
531 | spin_unlock_bh(&psock->link_lock); | |
532 | return link; | |
533 | } | |
534 | ||
535 | void __sk_psock_purge_ingress_msg(struct sk_psock *psock) | |
536 | { | |
537 | struct sk_msg *msg, *tmp; | |
538 | ||
539 | list_for_each_entry_safe(msg, tmp, &psock->ingress_msg, list) { | |
540 | list_del(&msg->list); | |
541 | sk_msg_free(psock->sk, msg); | |
542 | kfree(msg); | |
543 | } | |
544 | } | |
545 | ||
546 | static void sk_psock_zap_ingress(struct sk_psock *psock) | |
547 | { | |
548 | __skb_queue_purge(&psock->ingress_skb); | |
549 | __sk_psock_purge_ingress_msg(psock); | |
550 | } | |
551 | ||
552 | static void sk_psock_link_destroy(struct sk_psock *psock) | |
553 | { | |
554 | struct sk_psock_link *link, *tmp; | |
555 | ||
556 | list_for_each_entry_safe(link, tmp, &psock->link, list) { | |
557 | list_del(&link->list); | |
558 | sk_psock_free_link(link); | |
559 | } | |
560 | } | |
561 | ||
562 | static void sk_psock_destroy_deferred(struct work_struct *gc) | |
563 | { | |
564 | struct sk_psock *psock = container_of(gc, struct sk_psock, gc); | |
565 | ||
566 | /* No sk_callback_lock since already detached. */ | |
01489436 JF |
567 | |
568 | /* Parser has been stopped */ | |
569 | if (psock->progs.skb_parser) | |
570 | strp_done(&psock->parser.strp); | |
604326b4 DB |
571 | |
572 | cancel_work_sync(&psock->work); | |
573 | ||
574 | psock_progs_drop(&psock->progs); | |
575 | ||
576 | sk_psock_link_destroy(psock); | |
577 | sk_psock_cork_free(psock); | |
578 | sk_psock_zap_ingress(psock); | |
579 | ||
580 | if (psock->sk_redir) | |
581 | sock_put(psock->sk_redir); | |
582 | sock_put(psock->sk); | |
583 | kfree(psock); | |
584 | } | |
585 | ||
586 | void sk_psock_destroy(struct rcu_head *rcu) | |
587 | { | |
588 | struct sk_psock *psock = container_of(rcu, struct sk_psock, rcu); | |
589 | ||
590 | INIT_WORK(&psock->gc, sk_psock_destroy_deferred); | |
591 | schedule_work(&psock->gc); | |
592 | } | |
593 | EXPORT_SYMBOL_GPL(sk_psock_destroy); | |
594 | ||
595 | void sk_psock_drop(struct sock *sk, struct sk_psock *psock) | |
596 | { | |
604326b4 | 597 | sk_psock_cork_free(psock); |
a136678c | 598 | sk_psock_zap_ingress(psock); |
604326b4 DB |
599 | |
600 | write_lock_bh(&sk->sk_callback_lock); | |
95fa1454 JF |
601 | sk_psock_restore_proto(sk, psock); |
602 | rcu_assign_sk_user_data(sk, NULL); | |
604326b4 DB |
603 | if (psock->progs.skb_parser) |
604 | sk_psock_stop_strp(sk, psock); | |
605 | write_unlock_bh(&sk->sk_callback_lock); | |
606 | sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED); | |
607 | ||
0245b80e | 608 | call_rcu(&psock->rcu, sk_psock_destroy); |
604326b4 DB |
609 | } |
610 | EXPORT_SYMBOL_GPL(sk_psock_drop); | |
611 | ||
612 | static int sk_psock_map_verd(int verdict, bool redir) | |
613 | { | |
614 | switch (verdict) { | |
615 | case SK_PASS: | |
616 | return redir ? __SK_REDIRECT : __SK_PASS; | |
617 | case SK_DROP: | |
618 | default: | |
619 | break; | |
620 | } | |
621 | ||
622 | return __SK_DROP; | |
623 | } | |
624 | ||
625 | int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock, | |
626 | struct sk_msg *msg) | |
627 | { | |
628 | struct bpf_prog *prog; | |
629 | int ret; | |
630 | ||
604326b4 DB |
631 | rcu_read_lock(); |
632 | prog = READ_ONCE(psock->progs.msg_parser); | |
633 | if (unlikely(!prog)) { | |
634 | ret = __SK_PASS; | |
635 | goto out; | |
636 | } | |
637 | ||
638 | sk_msg_compute_data_pointers(msg); | |
639 | msg->sk = sk; | |
3d9f773c | 640 | ret = bpf_prog_run_pin_on_cpu(prog, msg); |
604326b4 DB |
641 | ret = sk_psock_map_verd(ret, msg->sk_redir); |
642 | psock->apply_bytes = msg->apply_bytes; | |
643 | if (ret == __SK_REDIRECT) { | |
644 | if (psock->sk_redir) | |
645 | sock_put(psock->sk_redir); | |
646 | psock->sk_redir = msg->sk_redir; | |
647 | if (!psock->sk_redir) { | |
648 | ret = __SK_DROP; | |
649 | goto out; | |
650 | } | |
651 | sock_hold(psock->sk_redir); | |
652 | } | |
653 | out: | |
654 | rcu_read_unlock(); | |
604326b4 DB |
655 | return ret; |
656 | } | |
657 | EXPORT_SYMBOL_GPL(sk_psock_msg_verdict); | |
658 | ||
659 | static int sk_psock_bpf_run(struct sk_psock *psock, struct bpf_prog *prog, | |
660 | struct sk_buff *skb) | |
661 | { | |
662 | int ret; | |
663 | ||
664 | skb->sk = psock->sk; | |
665 | bpf_compute_data_end_sk_skb(skb); | |
3d9f773c | 666 | ret = bpf_prog_run_pin_on_cpu(prog, skb); |
604326b4 DB |
667 | /* strparser clones the skb before handing it to a upper layer, |
668 | * meaning skb_orphan has been called. We NULL sk on the way out | |
669 | * to ensure we don't trigger a BUG_ON() in skb/sk operations | |
670 | * later and because we are not charging the memory of this skb | |
671 | * to any socket yet. | |
672 | */ | |
673 | skb->sk = NULL; | |
674 | return ret; | |
675 | } | |
676 | ||
677 | static struct sk_psock *sk_psock_from_strp(struct strparser *strp) | |
678 | { | |
679 | struct sk_psock_parser *parser; | |
680 | ||
681 | parser = container_of(strp, struct sk_psock_parser, strp); | |
682 | return container_of(parser, struct sk_psock, parser); | |
683 | } | |
684 | ||
685 | static void sk_psock_verdict_apply(struct sk_psock *psock, | |
686 | struct sk_buff *skb, int verdict) | |
687 | { | |
688 | struct sk_psock *psock_other; | |
689 | struct sock *sk_other; | |
690 | bool ingress; | |
691 | ||
692 | switch (verdict) { | |
51199405 JF |
693 | case __SK_PASS: |
694 | sk_other = psock->sk; | |
695 | if (sock_flag(sk_other, SOCK_DEAD) || | |
696 | !sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) { | |
697 | goto out_free; | |
698 | } | |
699 | if (atomic_read(&sk_other->sk_rmem_alloc) <= | |
700 | sk_other->sk_rcvbuf) { | |
701 | struct tcp_skb_cb *tcp = TCP_SKB_CB(skb); | |
702 | ||
703 | tcp->bpf.flags |= BPF_F_INGRESS; | |
704 | skb_queue_tail(&psock->ingress_skb, skb); | |
705 | schedule_work(&psock->work); | |
706 | break; | |
707 | } | |
708 | goto out_free; | |
604326b4 DB |
709 | case __SK_REDIRECT: |
710 | sk_other = tcp_skb_bpf_redirect_fetch(skb); | |
711 | if (unlikely(!sk_other)) | |
712 | goto out_free; | |
713 | psock_other = sk_psock(sk_other); | |
714 | if (!psock_other || sock_flag(sk_other, SOCK_DEAD) || | |
715 | !sk_psock_test_state(psock_other, SK_PSOCK_TX_ENABLED)) | |
716 | goto out_free; | |
717 | ingress = tcp_skb_bpf_ingress(skb); | |
718 | if ((!ingress && sock_writeable(sk_other)) || | |
719 | (ingress && | |
720 | atomic_read(&sk_other->sk_rmem_alloc) <= | |
721 | sk_other->sk_rcvbuf)) { | |
722 | if (!ingress) | |
723 | skb_set_owner_w(skb, sk_other); | |
724 | skb_queue_tail(&psock_other->ingress_skb, skb); | |
725 | schedule_work(&psock_other->work); | |
726 | break; | |
727 | } | |
728 | /* fall-through */ | |
729 | case __SK_DROP: | |
730 | /* fall-through */ | |
731 | default: | |
732 | out_free: | |
733 | kfree_skb(skb); | |
734 | } | |
735 | } | |
736 | ||
737 | static void sk_psock_strp_read(struct strparser *strp, struct sk_buff *skb) | |
738 | { | |
739 | struct sk_psock *psock = sk_psock_from_strp(strp); | |
740 | struct bpf_prog *prog; | |
741 | int ret = __SK_DROP; | |
742 | ||
743 | rcu_read_lock(); | |
744 | prog = READ_ONCE(psock->progs.skb_verdict); | |
745 | if (likely(prog)) { | |
746 | skb_orphan(skb); | |
747 | tcp_skb_bpf_redirect_clear(skb); | |
748 | ret = sk_psock_bpf_run(psock, prog, skb); | |
749 | ret = sk_psock_map_verd(ret, tcp_skb_bpf_redirect_fetch(skb)); | |
750 | } | |
751 | rcu_read_unlock(); | |
752 | sk_psock_verdict_apply(psock, skb, ret); | |
753 | } | |
754 | ||
755 | static int sk_psock_strp_read_done(struct strparser *strp, int err) | |
756 | { | |
757 | return err; | |
758 | } | |
759 | ||
760 | static int sk_psock_strp_parse(struct strparser *strp, struct sk_buff *skb) | |
761 | { | |
762 | struct sk_psock *psock = sk_psock_from_strp(strp); | |
763 | struct bpf_prog *prog; | |
764 | int ret = skb->len; | |
765 | ||
766 | rcu_read_lock(); | |
767 | prog = READ_ONCE(psock->progs.skb_parser); | |
768 | if (likely(prog)) | |
769 | ret = sk_psock_bpf_run(psock, prog, skb); | |
770 | rcu_read_unlock(); | |
771 | return ret; | |
772 | } | |
773 | ||
774 | /* Called with socket lock held. */ | |
552de910 | 775 | static void sk_psock_strp_data_ready(struct sock *sk) |
604326b4 DB |
776 | { |
777 | struct sk_psock *psock; | |
778 | ||
779 | rcu_read_lock(); | |
780 | psock = sk_psock(sk); | |
781 | if (likely(psock)) { | |
782 | write_lock_bh(&sk->sk_callback_lock); | |
783 | strp_data_ready(&psock->parser.strp); | |
784 | write_unlock_bh(&sk->sk_callback_lock); | |
785 | } | |
786 | rcu_read_unlock(); | |
787 | } | |
788 | ||
789 | static void sk_psock_write_space(struct sock *sk) | |
790 | { | |
791 | struct sk_psock *psock; | |
8163999d | 792 | void (*write_space)(struct sock *sk) = NULL; |
604326b4 DB |
793 | |
794 | rcu_read_lock(); | |
795 | psock = sk_psock(sk); | |
8163999d JF |
796 | if (likely(psock)) { |
797 | if (sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) | |
798 | schedule_work(&psock->work); | |
799 | write_space = psock->saved_write_space; | |
800 | } | |
604326b4 | 801 | rcu_read_unlock(); |
8163999d JF |
802 | if (write_space) |
803 | write_space(sk); | |
604326b4 DB |
804 | } |
805 | ||
806 | int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock) | |
807 | { | |
808 | static const struct strp_callbacks cb = { | |
809 | .rcv_msg = sk_psock_strp_read, | |
810 | .read_sock_done = sk_psock_strp_read_done, | |
811 | .parse_msg = sk_psock_strp_parse, | |
812 | }; | |
813 | ||
814 | psock->parser.enabled = false; | |
815 | return strp_init(&psock->parser.strp, sk, &cb); | |
816 | } | |
817 | ||
818 | void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock) | |
819 | { | |
820 | struct sk_psock_parser *parser = &psock->parser; | |
821 | ||
822 | if (parser->enabled) | |
823 | return; | |
824 | ||
825 | parser->saved_data_ready = sk->sk_data_ready; | |
552de910 | 826 | sk->sk_data_ready = sk_psock_strp_data_ready; |
604326b4 DB |
827 | sk->sk_write_space = sk_psock_write_space; |
828 | parser->enabled = true; | |
829 | } | |
830 | ||
831 | void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock) | |
832 | { | |
833 | struct sk_psock_parser *parser = &psock->parser; | |
834 | ||
835 | if (!parser->enabled) | |
836 | return; | |
837 | ||
838 | sk->sk_data_ready = parser->saved_data_ready; | |
839 | parser->saved_data_ready = NULL; | |
840 | strp_stop(&parser->strp); | |
841 | parser->enabled = false; | |
842 | } |