xref: /linux/io_uring/net.c (revision 7a9b709e7cc5ce1ffb84ce07bf6d157e1de758df)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/errno.h>
4 #include <linux/file.h>
5 #include <linux/slab.h>
6 #include <linux/net.h>
7 #include <linux/compat.h>
8 #include <net/compat.h>
9 #include <linux/io_uring.h>
10 
11 #include <uapi/linux/io_uring.h>
12 
13 #include "io_uring.h"
14 #include "kbuf.h"
15 #include "alloc_cache.h"
16 #include "net.h"
17 #include "notif.h"
18 #include "rsrc.h"
19 #include "zcrx.h"
20 
21 #if defined(CONFIG_NET)
22 struct io_shutdown {
23 	struct file			*file;
24 	int				how;
25 };
26 
27 struct io_accept {
28 	struct file			*file;
29 	struct sockaddr __user		*addr;
30 	int __user			*addr_len;
31 	int				flags;
32 	int				iou_flags;
33 	u32				file_slot;
34 	unsigned long			nofile;
35 };
36 
37 struct io_socket {
38 	struct file			*file;
39 	int				domain;
40 	int				type;
41 	int				protocol;
42 	int				flags;
43 	u32				file_slot;
44 	unsigned long			nofile;
45 };
46 
47 struct io_connect {
48 	struct file			*file;
49 	struct sockaddr __user		*addr;
50 	int				addr_len;
51 	bool				in_progress;
52 	bool				seen_econnaborted;
53 };
54 
55 struct io_bind {
56 	struct file			*file;
57 	int				addr_len;
58 };
59 
60 struct io_listen {
61 	struct file			*file;
62 	int				backlog;
63 };
64 
65 struct io_sr_msg {
66 	struct file			*file;
67 	union {
68 		struct compat_msghdr __user	*umsg_compat;
69 		struct user_msghdr __user	*umsg;
70 		void __user			*buf;
71 	};
72 	int				len;
73 	unsigned			done_io;
74 	unsigned			msg_flags;
75 	unsigned			nr_multishot_loops;
76 	u16				flags;
77 	/* initialised and used only by !msg send variants */
78 	u16				buf_group;
79 	bool				retry;
80 	void __user			*msg_control;
81 	/* used only for send zerocopy */
82 	struct io_kiocb 		*notif;
83 };
84 
85 /*
86  * Number of times we'll try and do receives if there's more data. If we
87  * exceed this limit, then add us to the back of the queue and retry from
88  * there. This helps fairness between flooding clients.
89  */
90 #define MULTISHOT_MAX_RETRY	32
91 
92 struct io_recvzc {
93 	struct file			*file;
94 	unsigned			msg_flags;
95 	u16				flags;
96 	u32				len;
97 	struct io_zcrx_ifq		*ifq;
98 };
99 
100 static int io_sg_from_iter_iovec(struct sk_buff *skb,
101 				 struct iov_iter *from, size_t length);
102 static int io_sg_from_iter(struct sk_buff *skb,
103 			   struct iov_iter *from, size_t length);
104 
105 int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
106 {
107 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
108 
109 	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
110 		     sqe->buf_index || sqe->splice_fd_in))
111 		return -EINVAL;
112 
113 	shutdown->how = READ_ONCE(sqe->len);
114 	req->flags |= REQ_F_FORCE_ASYNC;
115 	return 0;
116 }
117 
118 int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
119 {
120 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
121 	struct socket *sock;
122 	int ret;
123 
124 	WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
125 
126 	sock = sock_from_file(req->file);
127 	if (unlikely(!sock))
128 		return -ENOTSOCK;
129 
130 	ret = __sys_shutdown_sock(sock, shutdown->how);
131 	io_req_set_res(req, ret, 0);
132 	return IOU_OK;
133 }
134 
135 static bool io_net_retry(struct socket *sock, int flags)
136 {
137 	if (!(flags & MSG_WAITALL))
138 		return false;
139 	return sock->type == SOCK_STREAM || sock->type == SOCK_SEQPACKET;
140 }
141 
142 static void io_netmsg_iovec_free(struct io_async_msghdr *kmsg)
143 {
144 	if (kmsg->vec.iovec)
145 		io_vec_free(&kmsg->vec);
146 }
147 
148 static void io_netmsg_recycle(struct io_kiocb *req, unsigned int issue_flags)
149 {
150 	struct io_async_msghdr *hdr = req->async_data;
151 
152 	/* can't recycle, ensure we free the iovec if we have one */
153 	if (unlikely(issue_flags & IO_URING_F_UNLOCKED)) {
154 		io_netmsg_iovec_free(hdr);
155 		return;
156 	}
157 
158 	/* Let normal cleanup path reap it if we fail adding to the cache */
159 	io_alloc_cache_vec_kasan(&hdr->vec);
160 	if (hdr->vec.nr > IO_VEC_CACHE_SOFT_CAP)
161 		io_vec_free(&hdr->vec);
162 
163 	if (io_alloc_cache_put(&req->ctx->netmsg_cache, hdr)) {
164 		req->async_data = NULL;
165 		req->flags &= ~(REQ_F_ASYNC_DATA|REQ_F_NEED_CLEANUP);
166 	}
167 }
168 
169 static struct io_async_msghdr *io_msg_alloc_async(struct io_kiocb *req)
170 {
171 	struct io_ring_ctx *ctx = req->ctx;
172 	struct io_async_msghdr *hdr;
173 
174 	hdr = io_uring_alloc_async_data(&ctx->netmsg_cache, req);
175 	if (!hdr)
176 		return NULL;
177 
178 	/* If the async data was cached, we might have an iov cached inside. */
179 	if (hdr->vec.iovec)
180 		req->flags |= REQ_F_NEED_CLEANUP;
181 	return hdr;
182 }
183 
184 static inline void io_mshot_prep_retry(struct io_kiocb *req,
185 				       struct io_async_msghdr *kmsg)
186 {
187 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
188 
189 	req->flags &= ~REQ_F_BL_EMPTY;
190 	sr->done_io = 0;
191 	sr->retry = false;
192 	sr->len = 0; /* get from the provided buffer */
193 	req->buf_index = sr->buf_group;
194 }
195 
196 static int io_net_import_vec(struct io_kiocb *req, struct io_async_msghdr *iomsg,
197 			     const struct iovec __user *uiov, unsigned uvec_seg,
198 			     int ddir)
199 {
200 	struct iovec *iov;
201 	int ret, nr_segs;
202 
203 	if (iomsg->vec.iovec) {
204 		nr_segs = iomsg->vec.nr;
205 		iov = iomsg->vec.iovec;
206 	} else {
207 		nr_segs = 1;
208 		iov = &iomsg->fast_iov;
209 	}
210 
211 	ret = __import_iovec(ddir, uiov, uvec_seg, nr_segs, &iov,
212 			     &iomsg->msg.msg_iter, io_is_compat(req->ctx));
213 	if (unlikely(ret < 0))
214 		return ret;
215 
216 	if (iov) {
217 		req->flags |= REQ_F_NEED_CLEANUP;
218 		io_vec_reset_iovec(&iomsg->vec, iov, iomsg->msg.msg_iter.nr_segs);
219 	}
220 	return 0;
221 }
222 
223 static int io_compat_msg_copy_hdr(struct io_kiocb *req,
224 				  struct io_async_msghdr *iomsg,
225 				  struct compat_msghdr *msg, int ddir,
226 				  struct sockaddr __user **save_addr)
227 {
228 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
229 	struct compat_iovec __user *uiov;
230 	int ret;
231 
232 	if (copy_from_user(msg, sr->umsg_compat, sizeof(*msg)))
233 		return -EFAULT;
234 
235 	ret = __get_compat_msghdr(&iomsg->msg, msg, save_addr);
236 	if (ret)
237 		return ret;
238 
239 	uiov = compat_ptr(msg->msg_iov);
240 	if (req->flags & REQ_F_BUFFER_SELECT) {
241 		if (msg->msg_iovlen == 0) {
242 			sr->len = 0;
243 		} else if (msg->msg_iovlen > 1) {
244 			return -EINVAL;
245 		} else {
246 			struct compat_iovec tmp_iov;
247 
248 			if (copy_from_user(&tmp_iov, uiov, sizeof(tmp_iov)))
249 				return -EFAULT;
250 			sr->len = tmp_iov.iov_len;
251 		}
252 	}
253 	return 0;
254 }
255 
256 static int io_copy_msghdr_from_user(struct user_msghdr *msg,
257 				    struct user_msghdr __user *umsg)
258 {
259 	if (!user_access_begin(umsg, sizeof(*umsg)))
260 		return -EFAULT;
261 	unsafe_get_user(msg->msg_name, &umsg->msg_name, ua_end);
262 	unsafe_get_user(msg->msg_namelen, &umsg->msg_namelen, ua_end);
263 	unsafe_get_user(msg->msg_iov, &umsg->msg_iov, ua_end);
264 	unsafe_get_user(msg->msg_iovlen, &umsg->msg_iovlen, ua_end);
265 	unsafe_get_user(msg->msg_control, &umsg->msg_control, ua_end);
266 	unsafe_get_user(msg->msg_controllen, &umsg->msg_controllen, ua_end);
267 	user_access_end();
268 	return 0;
269 ua_end:
270 	user_access_end();
271 	return -EFAULT;
272 }
273 
274 static int io_msg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg,
275 			   struct user_msghdr *msg, int ddir,
276 			   struct sockaddr __user **save_addr)
277 {
278 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
279 	struct user_msghdr __user *umsg = sr->umsg;
280 	int ret;
281 
282 	iomsg->msg.msg_name = &iomsg->addr;
283 	iomsg->msg.msg_iter.nr_segs = 0;
284 
285 	if (io_is_compat(req->ctx)) {
286 		struct compat_msghdr cmsg;
287 
288 		ret = io_compat_msg_copy_hdr(req, iomsg, &cmsg, ddir, save_addr);
289 		if (ret)
290 			return ret;
291 
292 		memset(msg, 0, sizeof(*msg));
293 		msg->msg_namelen = cmsg.msg_namelen;
294 		msg->msg_controllen = cmsg.msg_controllen;
295 		msg->msg_iov = compat_ptr(cmsg.msg_iov);
296 		msg->msg_iovlen = cmsg.msg_iovlen;
297 		return 0;
298 	}
299 
300 	ret = io_copy_msghdr_from_user(msg, umsg);
301 	if (unlikely(ret))
302 		return ret;
303 
304 	msg->msg_flags = 0;
305 
306 	ret = __copy_msghdr(&iomsg->msg, msg, save_addr);
307 	if (ret)
308 		return ret;
309 
310 	if (req->flags & REQ_F_BUFFER_SELECT) {
311 		if (msg->msg_iovlen == 0) {
312 			sr->len = 0;
313 		} else if (msg->msg_iovlen > 1) {
314 			return -EINVAL;
315 		} else {
316 			struct iovec __user *uiov = msg->msg_iov;
317 			struct iovec tmp_iov;
318 
319 			if (copy_from_user(&tmp_iov, uiov, sizeof(tmp_iov)))
320 				return -EFAULT;
321 			sr->len = tmp_iov.iov_len;
322 		}
323 	}
324 	return 0;
325 }
326 
327 void io_sendmsg_recvmsg_cleanup(struct io_kiocb *req)
328 {
329 	struct io_async_msghdr *io = req->async_data;
330 
331 	io_netmsg_iovec_free(io);
332 }
333 
334 static int io_send_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
335 {
336 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
337 	struct io_async_msghdr *kmsg = req->async_data;
338 	void __user *addr;
339 	u16 addr_len;
340 	int ret;
341 
342 	sr->buf = u64_to_user_ptr(READ_ONCE(sqe->addr));
343 
344 	if (READ_ONCE(sqe->__pad3[0]))
345 		return -EINVAL;
346 
347 	kmsg->msg.msg_name = NULL;
348 	kmsg->msg.msg_namelen = 0;
349 	kmsg->msg.msg_control = NULL;
350 	kmsg->msg.msg_controllen = 0;
351 	kmsg->msg.msg_ubuf = NULL;
352 
353 	addr = u64_to_user_ptr(READ_ONCE(sqe->addr2));
354 	addr_len = READ_ONCE(sqe->addr_len);
355 	if (addr) {
356 		ret = move_addr_to_kernel(addr, addr_len, &kmsg->addr);
357 		if (unlikely(ret < 0))
358 			return ret;
359 		kmsg->msg.msg_name = &kmsg->addr;
360 		kmsg->msg.msg_namelen = addr_len;
361 	}
362 	if (sr->flags & IORING_RECVSEND_FIXED_BUF)
363 		return 0;
364 	if (!io_do_buffer_select(req)) {
365 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
366 				  &kmsg->msg.msg_iter);
367 		if (unlikely(ret < 0))
368 			return ret;
369 	}
370 	return 0;
371 }
372 
373 static int io_sendmsg_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
374 {
375 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
376 	struct io_async_msghdr *kmsg = req->async_data;
377 	struct user_msghdr msg;
378 	int ret;
379 
380 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
381 	ret = io_msg_copy_hdr(req, kmsg, &msg, ITER_SOURCE, NULL);
382 	if (unlikely(ret))
383 		return ret;
384 	/* save msg_control as sys_sendmsg() overwrites it */
385 	sr->msg_control = kmsg->msg.msg_control_user;
386 
387 	if (sr->flags & IORING_RECVSEND_FIXED_BUF) {
388 		kmsg->msg.msg_iter.nr_segs = msg.msg_iovlen;
389 		return io_prep_reg_iovec(req, &kmsg->vec, msg.msg_iov,
390 					 msg.msg_iovlen);
391 	}
392 	if (req->flags & REQ_F_BUFFER_SELECT)
393 		return 0;
394 	return io_net_import_vec(req, kmsg, msg.msg_iov, msg.msg_iovlen, ITER_SOURCE);
395 }
396 
397 #define SENDMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_BUNDLE)
398 
399 int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
400 {
401 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
402 
403 	sr->done_io = 0;
404 	sr->retry = false;
405 	sr->len = READ_ONCE(sqe->len);
406 	sr->flags = READ_ONCE(sqe->ioprio);
407 	if (sr->flags & ~SENDMSG_FLAGS)
408 		return -EINVAL;
409 	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
410 	if (sr->msg_flags & MSG_DONTWAIT)
411 		req->flags |= REQ_F_NOWAIT;
412 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
413 		if (req->opcode == IORING_OP_SENDMSG)
414 			return -EINVAL;
415 		if (!(req->flags & REQ_F_BUFFER_SELECT))
416 			return -EINVAL;
417 		sr->msg_flags |= MSG_WAITALL;
418 		sr->buf_group = req->buf_index;
419 		req->buf_list = NULL;
420 		req->flags |= REQ_F_MULTISHOT;
421 	}
422 
423 	if (io_is_compat(req->ctx))
424 		sr->msg_flags |= MSG_CMSG_COMPAT;
425 
426 	if (unlikely(!io_msg_alloc_async(req)))
427 		return -ENOMEM;
428 	if (req->opcode != IORING_OP_SENDMSG)
429 		return io_send_setup(req, sqe);
430 	if (unlikely(sqe->addr2 || sqe->file_index))
431 		return -EINVAL;
432 	return io_sendmsg_setup(req, sqe);
433 }
434 
435 static void io_req_msg_cleanup(struct io_kiocb *req,
436 			       unsigned int issue_flags)
437 {
438 	io_netmsg_recycle(req, issue_flags);
439 }
440 
441 /*
442  * For bundle completions, we need to figure out how many segments we consumed.
443  * A bundle could be using a single ITER_UBUF if that's all we mapped, or it
444  * could be using an ITER_IOVEC. If the latter, then if we consumed all of
445  * the segments, then it's a trivial questiont o answer. If we have residual
446  * data in the iter, then loop the segments to figure out how much we
447  * transferred.
448  */
449 static int io_bundle_nbufs(struct io_async_msghdr *kmsg, int ret)
450 {
451 	struct iovec *iov;
452 	int nbufs;
453 
454 	/* no data is always zero segments, and a ubuf is always 1 segment */
455 	if (ret <= 0)
456 		return 0;
457 	if (iter_is_ubuf(&kmsg->msg.msg_iter))
458 		return 1;
459 
460 	iov = kmsg->vec.iovec;
461 	if (!iov)
462 		iov = &kmsg->fast_iov;
463 
464 	/* if all data was transferred, it's basic pointer math */
465 	if (!iov_iter_count(&kmsg->msg.msg_iter))
466 		return iter_iov(&kmsg->msg.msg_iter) - iov;
467 
468 	/* short transfer, count segments */
469 	nbufs = 0;
470 	do {
471 		int this_len = min_t(int, iov[nbufs].iov_len, ret);
472 
473 		nbufs++;
474 		ret -= this_len;
475 	} while (ret);
476 
477 	return nbufs;
478 }
479 
480 static inline bool io_send_finish(struct io_kiocb *req, int *ret,
481 				  struct io_async_msghdr *kmsg,
482 				  unsigned issue_flags)
483 {
484 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
485 	bool bundle_finished = *ret <= 0;
486 	unsigned int cflags;
487 
488 	if (!(sr->flags & IORING_RECVSEND_BUNDLE)) {
489 		cflags = io_put_kbuf(req, *ret, issue_flags);
490 		goto finish;
491 	}
492 
493 	cflags = io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret), issue_flags);
494 
495 	if (bundle_finished || req->flags & REQ_F_BL_EMPTY)
496 		goto finish;
497 
498 	/*
499 	 * Fill CQE for this receive and see if we should keep trying to
500 	 * receive from this socket.
501 	 */
502 	if (io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
503 		io_mshot_prep_retry(req, kmsg);
504 		return false;
505 	}
506 
507 	/* Otherwise stop bundle and use the current result. */
508 finish:
509 	io_req_set_res(req, *ret, cflags);
510 	*ret = IOU_OK;
511 	return true;
512 }
513 
514 int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
515 {
516 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
517 	struct io_async_msghdr *kmsg = req->async_data;
518 	struct socket *sock;
519 	unsigned flags;
520 	int min_ret = 0;
521 	int ret;
522 
523 	sock = sock_from_file(req->file);
524 	if (unlikely(!sock))
525 		return -ENOTSOCK;
526 
527 	if (!(req->flags & REQ_F_POLLED) &&
528 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
529 		return -EAGAIN;
530 
531 	flags = sr->msg_flags;
532 	if (issue_flags & IO_URING_F_NONBLOCK)
533 		flags |= MSG_DONTWAIT;
534 	if (flags & MSG_WAITALL)
535 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
536 
537 	kmsg->msg.msg_control_user = sr->msg_control;
538 
539 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
540 
541 	if (ret < min_ret) {
542 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
543 			return -EAGAIN;
544 		if (ret > 0 && io_net_retry(sock, flags)) {
545 			kmsg->msg.msg_controllen = 0;
546 			kmsg->msg.msg_control = NULL;
547 			sr->done_io += ret;
548 			req->flags |= REQ_F_BL_NO_RECYCLE;
549 			return -EAGAIN;
550 		}
551 		if (ret == -ERESTARTSYS)
552 			ret = -EINTR;
553 		req_set_fail(req);
554 	}
555 	io_req_msg_cleanup(req, issue_flags);
556 	if (ret >= 0)
557 		ret += sr->done_io;
558 	else if (sr->done_io)
559 		ret = sr->done_io;
560 	io_req_set_res(req, ret, 0);
561 	return IOU_OK;
562 }
563 
564 static int io_send_select_buffer(struct io_kiocb *req, unsigned int issue_flags,
565 				 struct io_async_msghdr *kmsg)
566 {
567 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
568 
569 	int ret;
570 	struct buf_sel_arg arg = {
571 		.iovs = &kmsg->fast_iov,
572 		.max_len = min_not_zero(sr->len, INT_MAX),
573 		.nr_iovs = 1,
574 	};
575 
576 	if (kmsg->vec.iovec) {
577 		arg.nr_iovs = kmsg->vec.nr;
578 		arg.iovs = kmsg->vec.iovec;
579 		arg.mode = KBUF_MODE_FREE;
580 	}
581 
582 	if (!(sr->flags & IORING_RECVSEND_BUNDLE))
583 		arg.nr_iovs = 1;
584 	else
585 		arg.mode |= KBUF_MODE_EXPAND;
586 
587 	ret = io_buffers_select(req, &arg, issue_flags);
588 	if (unlikely(ret < 0))
589 		return ret;
590 
591 	if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->vec.iovec) {
592 		kmsg->vec.nr = ret;
593 		kmsg->vec.iovec = arg.iovs;
594 		req->flags |= REQ_F_NEED_CLEANUP;
595 	}
596 	sr->len = arg.out_len;
597 
598 	if (ret == 1) {
599 		sr->buf = arg.iovs[0].iov_base;
600 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
601 					&kmsg->msg.msg_iter);
602 		if (unlikely(ret))
603 			return ret;
604 	} else {
605 		iov_iter_init(&kmsg->msg.msg_iter, ITER_SOURCE,
606 				arg.iovs, ret, arg.out_len);
607 	}
608 
609 	return 0;
610 }
611 
612 int io_send(struct io_kiocb *req, unsigned int issue_flags)
613 {
614 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
615 	struct io_async_msghdr *kmsg = req->async_data;
616 	struct socket *sock;
617 	unsigned flags;
618 	int min_ret = 0;
619 	int ret;
620 
621 	sock = sock_from_file(req->file);
622 	if (unlikely(!sock))
623 		return -ENOTSOCK;
624 
625 	if (!(req->flags & REQ_F_POLLED) &&
626 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
627 		return -EAGAIN;
628 
629 	flags = sr->msg_flags;
630 	if (issue_flags & IO_URING_F_NONBLOCK)
631 		flags |= MSG_DONTWAIT;
632 
633 retry_bundle:
634 	if (io_do_buffer_select(req)) {
635 		ret = io_send_select_buffer(req, issue_flags, kmsg);
636 		if (ret)
637 			return ret;
638 	}
639 
640 	/*
641 	 * If MSG_WAITALL is set, or this is a bundle send, then we need
642 	 * the full amount. If just bundle is set, if we do a short send
643 	 * then we complete the bundle sequence rather than continue on.
644 	 */
645 	if (flags & MSG_WAITALL || sr->flags & IORING_RECVSEND_BUNDLE)
646 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
647 
648 	flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
649 	kmsg->msg.msg_flags = flags;
650 	ret = sock_sendmsg(sock, &kmsg->msg);
651 	if (ret < min_ret) {
652 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
653 			return -EAGAIN;
654 
655 		if (ret > 0 && io_net_retry(sock, flags)) {
656 			sr->len -= ret;
657 			sr->buf += ret;
658 			sr->done_io += ret;
659 			req->flags |= REQ_F_BL_NO_RECYCLE;
660 			return -EAGAIN;
661 		}
662 		if (ret == -ERESTARTSYS)
663 			ret = -EINTR;
664 		req_set_fail(req);
665 	}
666 	if (ret >= 0)
667 		ret += sr->done_io;
668 	else if (sr->done_io)
669 		ret = sr->done_io;
670 
671 	if (!io_send_finish(req, &ret, kmsg, issue_flags))
672 		goto retry_bundle;
673 
674 	io_req_msg_cleanup(req, issue_flags);
675 	return ret;
676 }
677 
678 static int io_recvmsg_mshot_prep(struct io_kiocb *req,
679 				 struct io_async_msghdr *iomsg,
680 				 int namelen, size_t controllen)
681 {
682 	if ((req->flags & (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) ==
683 			  (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) {
684 		int hdr;
685 
686 		if (unlikely(namelen < 0))
687 			return -EOVERFLOW;
688 		if (check_add_overflow(sizeof(struct io_uring_recvmsg_out),
689 					namelen, &hdr))
690 			return -EOVERFLOW;
691 		if (check_add_overflow(hdr, controllen, &hdr))
692 			return -EOVERFLOW;
693 
694 		iomsg->namelen = namelen;
695 		iomsg->controllen = controllen;
696 		return 0;
697 	}
698 
699 	return 0;
700 }
701 
702 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
703 			       struct io_async_msghdr *iomsg)
704 {
705 	struct user_msghdr msg;
706 	int ret;
707 
708 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_DEST, &iomsg->uaddr);
709 	if (unlikely(ret))
710 		return ret;
711 
712 	if (!(req->flags & REQ_F_BUFFER_SELECT)) {
713 		ret = io_net_import_vec(req, iomsg, msg.msg_iov, msg.msg_iovlen,
714 					ITER_DEST);
715 		if (unlikely(ret))
716 			return ret;
717 	}
718 	return io_recvmsg_mshot_prep(req, iomsg, msg.msg_namelen,
719 					msg.msg_controllen);
720 }
721 
722 static int io_recvmsg_prep_setup(struct io_kiocb *req)
723 {
724 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
725 	struct io_async_msghdr *kmsg;
726 	int ret;
727 
728 	kmsg = io_msg_alloc_async(req);
729 	if (unlikely(!kmsg))
730 		return -ENOMEM;
731 
732 	if (req->opcode == IORING_OP_RECV) {
733 		kmsg->msg.msg_name = NULL;
734 		kmsg->msg.msg_namelen = 0;
735 		kmsg->msg.msg_inq = 0;
736 		kmsg->msg.msg_control = NULL;
737 		kmsg->msg.msg_get_inq = 1;
738 		kmsg->msg.msg_controllen = 0;
739 		kmsg->msg.msg_iocb = NULL;
740 		kmsg->msg.msg_ubuf = NULL;
741 
742 		if (!io_do_buffer_select(req)) {
743 			ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
744 					  &kmsg->msg.msg_iter);
745 			if (unlikely(ret))
746 				return ret;
747 		}
748 		return 0;
749 	}
750 
751 	return io_recvmsg_copy_hdr(req, kmsg);
752 }
753 
754 #define RECVMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT | \
755 			IORING_RECVSEND_BUNDLE)
756 
757 int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
758 {
759 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
760 
761 	sr->done_io = 0;
762 	sr->retry = false;
763 
764 	if (unlikely(sqe->file_index || sqe->addr2))
765 		return -EINVAL;
766 
767 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
768 	sr->len = READ_ONCE(sqe->len);
769 	sr->flags = READ_ONCE(sqe->ioprio);
770 	if (sr->flags & ~RECVMSG_FLAGS)
771 		return -EINVAL;
772 	sr->msg_flags = READ_ONCE(sqe->msg_flags);
773 	if (sr->msg_flags & MSG_DONTWAIT)
774 		req->flags |= REQ_F_NOWAIT;
775 	if (sr->msg_flags & MSG_ERRQUEUE)
776 		req->flags |= REQ_F_CLEAR_POLLIN;
777 	if (req->flags & REQ_F_BUFFER_SELECT) {
778 		/*
779 		 * Store the buffer group for this multishot receive separately,
780 		 * as if we end up doing an io-wq based issue that selects a
781 		 * buffer, it has to be committed immediately and that will
782 		 * clear ->buf_list. This means we lose the link to the buffer
783 		 * list, and the eventual buffer put on completion then cannot
784 		 * restore it.
785 		 */
786 		sr->buf_group = req->buf_index;
787 		req->buf_list = NULL;
788 	}
789 	if (sr->flags & IORING_RECV_MULTISHOT) {
790 		if (!(req->flags & REQ_F_BUFFER_SELECT))
791 			return -EINVAL;
792 		if (sr->msg_flags & MSG_WAITALL)
793 			return -EINVAL;
794 		if (req->opcode == IORING_OP_RECV && sr->len)
795 			return -EINVAL;
796 		req->flags |= REQ_F_APOLL_MULTISHOT;
797 	}
798 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
799 		if (req->opcode == IORING_OP_RECVMSG)
800 			return -EINVAL;
801 	}
802 
803 	if (io_is_compat(req->ctx))
804 		sr->msg_flags |= MSG_CMSG_COMPAT;
805 
806 	sr->nr_multishot_loops = 0;
807 	return io_recvmsg_prep_setup(req);
808 }
809 
810 /* bits to clear in old and inherit in new cflags on bundle retry */
811 #define CQE_F_MASK	(IORING_CQE_F_SOCK_NONEMPTY|IORING_CQE_F_MORE)
812 
813 /*
814  * Finishes io_recv and io_recvmsg.
815  *
816  * Returns true if it is actually finished, or false if it should run
817  * again (for multishot).
818  */
819 static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
820 				  struct io_async_msghdr *kmsg,
821 				  bool mshot_finished, unsigned issue_flags)
822 {
823 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
824 	unsigned int cflags = 0;
825 
826 	if (kmsg->msg.msg_inq > 0)
827 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
828 
829 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
830 		cflags |= io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret),
831 				      issue_flags);
832 		if (sr->retry)
833 			cflags = req->cqe.flags | (cflags & CQE_F_MASK);
834 		/* bundle with no more immediate buffers, we're done */
835 		if (req->flags & REQ_F_BL_EMPTY)
836 			goto finish;
837 		/* if more is available, retry and append to this one */
838 		if (!sr->retry && kmsg->msg.msg_inq > 0 && *ret > 0) {
839 			req->cqe.flags = cflags & ~CQE_F_MASK;
840 			sr->len = kmsg->msg.msg_inq;
841 			sr->done_io += *ret;
842 			sr->retry = true;
843 			return false;
844 		}
845 	} else {
846 		cflags |= io_put_kbuf(req, *ret, issue_flags);
847 	}
848 
849 	/*
850 	 * Fill CQE for this receive and see if we should keep trying to
851 	 * receive from this socket.
852 	 */
853 	if ((req->flags & REQ_F_APOLL_MULTISHOT) && !mshot_finished &&
854 	    io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
855 		*ret = IOU_RETRY;
856 		io_mshot_prep_retry(req, kmsg);
857 		/* Known not-empty or unknown state, retry */
858 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || kmsg->msg.msg_inq < 0) {
859 			if (sr->nr_multishot_loops++ < MULTISHOT_MAX_RETRY)
860 				return false;
861 			/* mshot retries exceeded, force a requeue */
862 			sr->nr_multishot_loops = 0;
863 			if (issue_flags & IO_URING_F_MULTISHOT)
864 				*ret = IOU_REQUEUE;
865 		}
866 		return true;
867 	}
868 
869 	/* Finish the request / stop multishot. */
870 finish:
871 	io_req_set_res(req, *ret, cflags);
872 	*ret = IOU_COMPLETE;
873 	io_req_msg_cleanup(req, issue_flags);
874 	return true;
875 }
876 
877 static int io_recvmsg_prep_multishot(struct io_async_msghdr *kmsg,
878 				     struct io_sr_msg *sr, void __user **buf,
879 				     size_t *len)
880 {
881 	unsigned long ubuf = (unsigned long) *buf;
882 	unsigned long hdr;
883 
884 	hdr = sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
885 		kmsg->controllen;
886 	if (*len < hdr)
887 		return -EFAULT;
888 
889 	if (kmsg->controllen) {
890 		unsigned long control = ubuf + hdr - kmsg->controllen;
891 
892 		kmsg->msg.msg_control_user = (void __user *) control;
893 		kmsg->msg.msg_controllen = kmsg->controllen;
894 	}
895 
896 	sr->buf = *buf; /* stash for later copy */
897 	*buf = (void __user *) (ubuf + hdr);
898 	kmsg->payloadlen = *len = *len - hdr;
899 	return 0;
900 }
901 
902 struct io_recvmsg_multishot_hdr {
903 	struct io_uring_recvmsg_out msg;
904 	struct sockaddr_storage addr;
905 };
906 
907 static int io_recvmsg_multishot(struct socket *sock, struct io_sr_msg *io,
908 				struct io_async_msghdr *kmsg,
909 				unsigned int flags, bool *finished)
910 {
911 	int err;
912 	int copy_len;
913 	struct io_recvmsg_multishot_hdr hdr;
914 
915 	if (kmsg->namelen)
916 		kmsg->msg.msg_name = &hdr.addr;
917 	kmsg->msg.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
918 	kmsg->msg.msg_namelen = 0;
919 
920 	if (sock->file->f_flags & O_NONBLOCK)
921 		flags |= MSG_DONTWAIT;
922 
923 	err = sock_recvmsg(sock, &kmsg->msg, flags);
924 	*finished = err <= 0;
925 	if (err < 0)
926 		return err;
927 
928 	hdr.msg = (struct io_uring_recvmsg_out) {
929 		.controllen = kmsg->controllen - kmsg->msg.msg_controllen,
930 		.flags = kmsg->msg.msg_flags & ~MSG_CMSG_COMPAT
931 	};
932 
933 	hdr.msg.payloadlen = err;
934 	if (err > kmsg->payloadlen)
935 		err = kmsg->payloadlen;
936 
937 	copy_len = sizeof(struct io_uring_recvmsg_out);
938 	if (kmsg->msg.msg_namelen > kmsg->namelen)
939 		copy_len += kmsg->namelen;
940 	else
941 		copy_len += kmsg->msg.msg_namelen;
942 
943 	/*
944 	 *      "fromlen shall refer to the value before truncation.."
945 	 *                      1003.1g
946 	 */
947 	hdr.msg.namelen = kmsg->msg.msg_namelen;
948 
949 	/* ensure that there is no gap between hdr and sockaddr_storage */
950 	BUILD_BUG_ON(offsetof(struct io_recvmsg_multishot_hdr, addr) !=
951 		     sizeof(struct io_uring_recvmsg_out));
952 	if (copy_to_user(io->buf, &hdr, copy_len)) {
953 		*finished = true;
954 		return -EFAULT;
955 	}
956 
957 	return sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
958 			kmsg->controllen + err;
959 }
960 
961 int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
962 {
963 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
964 	struct io_async_msghdr *kmsg = req->async_data;
965 	struct socket *sock;
966 	unsigned flags;
967 	int ret, min_ret = 0;
968 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
969 	bool mshot_finished = true;
970 
971 	sock = sock_from_file(req->file);
972 	if (unlikely(!sock))
973 		return -ENOTSOCK;
974 
975 	if (!(req->flags & REQ_F_POLLED) &&
976 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
977 		return -EAGAIN;
978 
979 	flags = sr->msg_flags;
980 	if (force_nonblock)
981 		flags |= MSG_DONTWAIT;
982 
983 retry_multishot:
984 	if (io_do_buffer_select(req)) {
985 		void __user *buf;
986 		size_t len = sr->len;
987 
988 		buf = io_buffer_select(req, &len, issue_flags);
989 		if (!buf)
990 			return -ENOBUFS;
991 
992 		if (req->flags & REQ_F_APOLL_MULTISHOT) {
993 			ret = io_recvmsg_prep_multishot(kmsg, sr, &buf, &len);
994 			if (ret) {
995 				io_kbuf_recycle(req, issue_flags);
996 				return ret;
997 			}
998 		}
999 
1000 		iov_iter_ubuf(&kmsg->msg.msg_iter, ITER_DEST, buf, len);
1001 	}
1002 
1003 	kmsg->msg.msg_get_inq = 1;
1004 	kmsg->msg.msg_inq = -1;
1005 	if (req->flags & REQ_F_APOLL_MULTISHOT) {
1006 		ret = io_recvmsg_multishot(sock, sr, kmsg, flags,
1007 					   &mshot_finished);
1008 	} else {
1009 		/* disable partial retry for recvmsg with cmsg attached */
1010 		if (flags & MSG_WAITALL && !kmsg->msg.msg_controllen)
1011 			min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1012 
1013 		ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg,
1014 					 kmsg->uaddr, flags);
1015 	}
1016 
1017 	if (ret < min_ret) {
1018 		if (ret == -EAGAIN && force_nonblock) {
1019 			if (issue_flags & IO_URING_F_MULTISHOT)
1020 				io_kbuf_recycle(req, issue_flags);
1021 
1022 			return IOU_RETRY;
1023 		}
1024 		if (ret > 0 && io_net_retry(sock, flags)) {
1025 			sr->done_io += ret;
1026 			req->flags |= REQ_F_BL_NO_RECYCLE;
1027 			return IOU_RETRY;
1028 		}
1029 		if (ret == -ERESTARTSYS)
1030 			ret = -EINTR;
1031 		req_set_fail(req);
1032 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1033 		req_set_fail(req);
1034 	}
1035 
1036 	if (ret > 0)
1037 		ret += sr->done_io;
1038 	else if (sr->done_io)
1039 		ret = sr->done_io;
1040 	else
1041 		io_kbuf_recycle(req, issue_flags);
1042 
1043 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1044 		goto retry_multishot;
1045 
1046 	return ret;
1047 }
1048 
1049 static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg,
1050 			      size_t *len, unsigned int issue_flags)
1051 {
1052 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1053 	int ret;
1054 
1055 	/*
1056 	 * If the ring isn't locked, then don't use the peek interface
1057 	 * to grab multiple buffers as we will lock/unlock between
1058 	 * this selection and posting the buffers.
1059 	 */
1060 	if (!(issue_flags & IO_URING_F_UNLOCKED) &&
1061 	    sr->flags & IORING_RECVSEND_BUNDLE) {
1062 		struct buf_sel_arg arg = {
1063 			.iovs = &kmsg->fast_iov,
1064 			.nr_iovs = 1,
1065 			.mode = KBUF_MODE_EXPAND,
1066 		};
1067 
1068 		if (kmsg->vec.iovec) {
1069 			arg.nr_iovs = kmsg->vec.nr;
1070 			arg.iovs = kmsg->vec.iovec;
1071 			arg.mode |= KBUF_MODE_FREE;
1072 		}
1073 
1074 		if (kmsg->msg.msg_inq > 0)
1075 			arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq);
1076 
1077 		ret = io_buffers_peek(req, &arg);
1078 		if (unlikely(ret < 0))
1079 			return ret;
1080 
1081 		/* special case 1 vec, can be a fast path */
1082 		if (ret == 1) {
1083 			sr->buf = arg.iovs[0].iov_base;
1084 			sr->len = arg.iovs[0].iov_len;
1085 			goto map_ubuf;
1086 		}
1087 		iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, arg.iovs, ret,
1088 				arg.out_len);
1089 		if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->vec.iovec) {
1090 			kmsg->vec.nr = ret;
1091 			kmsg->vec.iovec = arg.iovs;
1092 			req->flags |= REQ_F_NEED_CLEANUP;
1093 		}
1094 	} else {
1095 		void __user *buf;
1096 
1097 		*len = sr->len;
1098 		buf = io_buffer_select(req, len, issue_flags);
1099 		if (!buf)
1100 			return -ENOBUFS;
1101 		sr->buf = buf;
1102 		sr->len = *len;
1103 map_ubuf:
1104 		ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
1105 				  &kmsg->msg.msg_iter);
1106 		if (unlikely(ret))
1107 			return ret;
1108 	}
1109 
1110 	return 0;
1111 }
1112 
1113 int io_recv(struct io_kiocb *req, unsigned int issue_flags)
1114 {
1115 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1116 	struct io_async_msghdr *kmsg = req->async_data;
1117 	struct socket *sock;
1118 	unsigned flags;
1119 	int ret, min_ret = 0;
1120 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1121 	size_t len = sr->len;
1122 	bool mshot_finished;
1123 
1124 	if (!(req->flags & REQ_F_POLLED) &&
1125 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1126 		return -EAGAIN;
1127 
1128 	sock = sock_from_file(req->file);
1129 	if (unlikely(!sock))
1130 		return -ENOTSOCK;
1131 
1132 	flags = sr->msg_flags;
1133 	if (force_nonblock)
1134 		flags |= MSG_DONTWAIT;
1135 
1136 retry_multishot:
1137 	if (io_do_buffer_select(req)) {
1138 		ret = io_recv_buf_select(req, kmsg, &len, issue_flags);
1139 		if (unlikely(ret)) {
1140 			kmsg->msg.msg_inq = -1;
1141 			goto out_free;
1142 		}
1143 		sr->buf = NULL;
1144 	}
1145 
1146 	kmsg->msg.msg_flags = 0;
1147 	kmsg->msg.msg_inq = -1;
1148 
1149 	if (flags & MSG_WAITALL)
1150 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1151 
1152 	ret = sock_recvmsg(sock, &kmsg->msg, flags);
1153 	if (ret < min_ret) {
1154 		if (ret == -EAGAIN && force_nonblock) {
1155 			if (issue_flags & IO_URING_F_MULTISHOT)
1156 				io_kbuf_recycle(req, issue_flags);
1157 
1158 			return IOU_RETRY;
1159 		}
1160 		if (ret > 0 && io_net_retry(sock, flags)) {
1161 			sr->len -= ret;
1162 			sr->buf += ret;
1163 			sr->done_io += ret;
1164 			req->flags |= REQ_F_BL_NO_RECYCLE;
1165 			return -EAGAIN;
1166 		}
1167 		if (ret == -ERESTARTSYS)
1168 			ret = -EINTR;
1169 		req_set_fail(req);
1170 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1171 out_free:
1172 		req_set_fail(req);
1173 	}
1174 
1175 	mshot_finished = ret <= 0;
1176 	if (ret > 0)
1177 		ret += sr->done_io;
1178 	else if (sr->done_io)
1179 		ret = sr->done_io;
1180 	else
1181 		io_kbuf_recycle(req, issue_flags);
1182 
1183 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1184 		goto retry_multishot;
1185 
1186 	return ret;
1187 }
1188 
1189 int io_recvzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1190 {
1191 	struct io_recvzc *zc = io_kiocb_to_cmd(req, struct io_recvzc);
1192 	unsigned ifq_idx;
1193 
1194 	if (unlikely(sqe->file_index || sqe->addr2 || sqe->addr ||
1195 		     sqe->addr3))
1196 		return -EINVAL;
1197 
1198 	ifq_idx = READ_ONCE(sqe->zcrx_ifq_idx);
1199 	if (ifq_idx != 0)
1200 		return -EINVAL;
1201 	zc->ifq = req->ctx->ifq;
1202 	if (!zc->ifq)
1203 		return -EINVAL;
1204 	zc->len = READ_ONCE(sqe->len);
1205 	zc->flags = READ_ONCE(sqe->ioprio);
1206 	zc->msg_flags = READ_ONCE(sqe->msg_flags);
1207 	if (zc->msg_flags)
1208 		return -EINVAL;
1209 	if (zc->flags & ~(IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT))
1210 		return -EINVAL;
1211 	/* multishot required */
1212 	if (!(zc->flags & IORING_RECV_MULTISHOT))
1213 		return -EINVAL;
1214 	/* All data completions are posted as aux CQEs. */
1215 	req->flags |= REQ_F_APOLL_MULTISHOT;
1216 
1217 	return 0;
1218 }
1219 
1220 int io_recvzc(struct io_kiocb *req, unsigned int issue_flags)
1221 {
1222 	struct io_recvzc *zc = io_kiocb_to_cmd(req, struct io_recvzc);
1223 	struct socket *sock;
1224 	unsigned int len;
1225 	int ret;
1226 
1227 	if (!(req->flags & REQ_F_POLLED) &&
1228 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1229 		return -EAGAIN;
1230 
1231 	sock = sock_from_file(req->file);
1232 	if (unlikely(!sock))
1233 		return -ENOTSOCK;
1234 
1235 	len = zc->len;
1236 	ret = io_zcrx_recv(req, zc->ifq, sock, zc->msg_flags | MSG_DONTWAIT,
1237 			   issue_flags, &zc->len);
1238 	if (len && zc->len == 0) {
1239 		io_req_set_res(req, 0, 0);
1240 
1241 		return IOU_COMPLETE;
1242 	}
1243 	if (unlikely(ret <= 0) && ret != -EAGAIN) {
1244 		if (ret == -ERESTARTSYS)
1245 			ret = -EINTR;
1246 		if (ret == IOU_REQUEUE)
1247 			return IOU_REQUEUE;
1248 
1249 		req_set_fail(req);
1250 		io_req_set_res(req, ret, 0);
1251 		return IOU_COMPLETE;
1252 	}
1253 	return IOU_RETRY;
1254 }
1255 
1256 void io_send_zc_cleanup(struct io_kiocb *req)
1257 {
1258 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1259 	struct io_async_msghdr *io = req->async_data;
1260 
1261 	if (req_has_async_data(req))
1262 		io_netmsg_iovec_free(io);
1263 	if (zc->notif) {
1264 		io_notif_flush(zc->notif);
1265 		zc->notif = NULL;
1266 	}
1267 }
1268 
1269 #define IO_ZC_FLAGS_COMMON (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_FIXED_BUF)
1270 #define IO_ZC_FLAGS_VALID  (IO_ZC_FLAGS_COMMON | IORING_SEND_ZC_REPORT_USAGE)
1271 
1272 int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1273 {
1274 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1275 	struct io_ring_ctx *ctx = req->ctx;
1276 	struct io_async_msghdr *iomsg;
1277 	struct io_kiocb *notif;
1278 	int ret;
1279 
1280 	zc->done_io = 0;
1281 	zc->retry = false;
1282 
1283 	if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3)))
1284 		return -EINVAL;
1285 	/* we don't support IOSQE_CQE_SKIP_SUCCESS just yet */
1286 	if (req->flags & REQ_F_CQE_SKIP)
1287 		return -EINVAL;
1288 
1289 	notif = zc->notif = io_alloc_notif(ctx);
1290 	if (!notif)
1291 		return -ENOMEM;
1292 	notif->cqe.user_data = req->cqe.user_data;
1293 	notif->cqe.res = 0;
1294 	notif->cqe.flags = IORING_CQE_F_NOTIF;
1295 	req->flags |= REQ_F_NEED_CLEANUP | REQ_F_POLL_NO_LAZY;
1296 
1297 	zc->flags = READ_ONCE(sqe->ioprio);
1298 	if (unlikely(zc->flags & ~IO_ZC_FLAGS_COMMON)) {
1299 		if (zc->flags & ~IO_ZC_FLAGS_VALID)
1300 			return -EINVAL;
1301 		if (zc->flags & IORING_SEND_ZC_REPORT_USAGE) {
1302 			struct io_notif_data *nd = io_notif_to_data(notif);
1303 
1304 			nd->zc_report = true;
1305 			nd->zc_used = false;
1306 			nd->zc_copied = false;
1307 		}
1308 	}
1309 
1310 	zc->len = READ_ONCE(sqe->len);
1311 	zc->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL | MSG_ZEROCOPY;
1312 	req->buf_index = READ_ONCE(sqe->buf_index);
1313 	if (zc->msg_flags & MSG_DONTWAIT)
1314 		req->flags |= REQ_F_NOWAIT;
1315 
1316 	if (io_is_compat(req->ctx))
1317 		zc->msg_flags |= MSG_CMSG_COMPAT;
1318 
1319 	iomsg = io_msg_alloc_async(req);
1320 	if (unlikely(!iomsg))
1321 		return -ENOMEM;
1322 
1323 	if (req->opcode == IORING_OP_SEND_ZC) {
1324 		if (zc->flags & IORING_RECVSEND_FIXED_BUF)
1325 			req->flags |= REQ_F_IMPORT_BUFFER;
1326 		ret = io_send_setup(req, sqe);
1327 	} else {
1328 		if (unlikely(sqe->addr2 || sqe->file_index))
1329 			return -EINVAL;
1330 		ret = io_sendmsg_setup(req, sqe);
1331 	}
1332 	if (unlikely(ret))
1333 		return ret;
1334 
1335 	if (!(zc->flags & IORING_RECVSEND_FIXED_BUF)) {
1336 		iomsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1337 		return io_notif_account_mem(zc->notif, iomsg->msg.msg_iter.count);
1338 	}
1339 	iomsg->msg.sg_from_iter = io_sg_from_iter;
1340 	return 0;
1341 }
1342 
1343 static int io_sg_from_iter_iovec(struct sk_buff *skb,
1344 				 struct iov_iter *from, size_t length)
1345 {
1346 	skb_zcopy_downgrade_managed(skb);
1347 	return zerocopy_fill_skb_from_iter(skb, from, length);
1348 }
1349 
1350 static int io_sg_from_iter(struct sk_buff *skb,
1351 			   struct iov_iter *from, size_t length)
1352 {
1353 	struct skb_shared_info *shinfo = skb_shinfo(skb);
1354 	int frag = shinfo->nr_frags;
1355 	int ret = 0;
1356 	struct bvec_iter bi;
1357 	ssize_t copied = 0;
1358 	unsigned long truesize = 0;
1359 
1360 	if (!frag)
1361 		shinfo->flags |= SKBFL_MANAGED_FRAG_REFS;
1362 	else if (unlikely(!skb_zcopy_managed(skb)))
1363 		return zerocopy_fill_skb_from_iter(skb, from, length);
1364 
1365 	bi.bi_size = min(from->count, length);
1366 	bi.bi_bvec_done = from->iov_offset;
1367 	bi.bi_idx = 0;
1368 
1369 	while (bi.bi_size && frag < MAX_SKB_FRAGS) {
1370 		struct bio_vec v = mp_bvec_iter_bvec(from->bvec, bi);
1371 
1372 		copied += v.bv_len;
1373 		truesize += PAGE_ALIGN(v.bv_len + v.bv_offset);
1374 		__skb_fill_page_desc_noacc(shinfo, frag++, v.bv_page,
1375 					   v.bv_offset, v.bv_len);
1376 		bvec_iter_advance_single(from->bvec, &bi, v.bv_len);
1377 	}
1378 	if (bi.bi_size)
1379 		ret = -EMSGSIZE;
1380 
1381 	shinfo->nr_frags = frag;
1382 	from->bvec += bi.bi_idx;
1383 	from->nr_segs -= bi.bi_idx;
1384 	from->count -= copied;
1385 	from->iov_offset = bi.bi_bvec_done;
1386 
1387 	skb->data_len += copied;
1388 	skb->len += copied;
1389 	skb->truesize += truesize;
1390 	return ret;
1391 }
1392 
1393 static int io_send_zc_import(struct io_kiocb *req, unsigned int issue_flags)
1394 {
1395 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1396 	struct io_async_msghdr *kmsg = req->async_data;
1397 
1398 	WARN_ON_ONCE(!(sr->flags & IORING_RECVSEND_FIXED_BUF));
1399 
1400 	sr->notif->buf_index = req->buf_index;
1401 	return io_import_reg_buf(sr->notif, &kmsg->msg.msg_iter,
1402 				(u64)(uintptr_t)sr->buf, sr->len,
1403 				ITER_SOURCE, issue_flags);
1404 }
1405 
1406 int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
1407 {
1408 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1409 	struct io_async_msghdr *kmsg = req->async_data;
1410 	struct socket *sock;
1411 	unsigned msg_flags;
1412 	int ret, min_ret = 0;
1413 
1414 	sock = sock_from_file(req->file);
1415 	if (unlikely(!sock))
1416 		return -ENOTSOCK;
1417 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1418 		return -EOPNOTSUPP;
1419 
1420 	if (!(req->flags & REQ_F_POLLED) &&
1421 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1422 		return -EAGAIN;
1423 
1424 	if (req->flags & REQ_F_IMPORT_BUFFER) {
1425 		req->flags &= ~REQ_F_IMPORT_BUFFER;
1426 		ret = io_send_zc_import(req, issue_flags);
1427 		if (unlikely(ret))
1428 			return ret;
1429 	}
1430 
1431 	msg_flags = zc->msg_flags;
1432 	if (issue_flags & IO_URING_F_NONBLOCK)
1433 		msg_flags |= MSG_DONTWAIT;
1434 	if (msg_flags & MSG_WAITALL)
1435 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1436 	msg_flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
1437 
1438 	kmsg->msg.msg_flags = msg_flags;
1439 	kmsg->msg.msg_ubuf = &io_notif_to_data(zc->notif)->uarg;
1440 	ret = sock_sendmsg(sock, &kmsg->msg);
1441 
1442 	if (unlikely(ret < min_ret)) {
1443 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1444 			return -EAGAIN;
1445 
1446 		if (ret > 0 && io_net_retry(sock, kmsg->msg.msg_flags)) {
1447 			zc->len -= ret;
1448 			zc->buf += ret;
1449 			zc->done_io += ret;
1450 			req->flags |= REQ_F_BL_NO_RECYCLE;
1451 			return -EAGAIN;
1452 		}
1453 		if (ret == -ERESTARTSYS)
1454 			ret = -EINTR;
1455 		req_set_fail(req);
1456 	}
1457 
1458 	if (ret >= 0)
1459 		ret += zc->done_io;
1460 	else if (zc->done_io)
1461 		ret = zc->done_io;
1462 
1463 	/*
1464 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1465 	 * flushing notif to io_send_zc_cleanup()
1466 	 */
1467 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1468 		io_notif_flush(zc->notif);
1469 		zc->notif = NULL;
1470 		io_req_msg_cleanup(req, 0);
1471 	}
1472 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1473 	return IOU_OK;
1474 }
1475 
1476 int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags)
1477 {
1478 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1479 	struct io_async_msghdr *kmsg = req->async_data;
1480 	struct socket *sock;
1481 	unsigned flags;
1482 	int ret, min_ret = 0;
1483 
1484 	if (req->flags & REQ_F_IMPORT_BUFFER) {
1485 		unsigned uvec_segs = kmsg->msg.msg_iter.nr_segs;
1486 		int ret;
1487 
1488 		ret = io_import_reg_vec(ITER_SOURCE, &kmsg->msg.msg_iter, req,
1489 					&kmsg->vec, uvec_segs, issue_flags);
1490 		if (unlikely(ret))
1491 			return ret;
1492 		req->flags &= ~REQ_F_IMPORT_BUFFER;
1493 	}
1494 
1495 	sock = sock_from_file(req->file);
1496 	if (unlikely(!sock))
1497 		return -ENOTSOCK;
1498 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1499 		return -EOPNOTSUPP;
1500 
1501 	if (!(req->flags & REQ_F_POLLED) &&
1502 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1503 		return -EAGAIN;
1504 
1505 	flags = sr->msg_flags;
1506 	if (issue_flags & IO_URING_F_NONBLOCK)
1507 		flags |= MSG_DONTWAIT;
1508 	if (flags & MSG_WAITALL)
1509 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1510 
1511 	kmsg->msg.msg_control_user = sr->msg_control;
1512 	kmsg->msg.msg_ubuf = &io_notif_to_data(sr->notif)->uarg;
1513 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
1514 
1515 	if (unlikely(ret < min_ret)) {
1516 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1517 			return -EAGAIN;
1518 
1519 		if (ret > 0 && io_net_retry(sock, flags)) {
1520 			sr->done_io += ret;
1521 			req->flags |= REQ_F_BL_NO_RECYCLE;
1522 			return -EAGAIN;
1523 		}
1524 		if (ret == -ERESTARTSYS)
1525 			ret = -EINTR;
1526 		req_set_fail(req);
1527 	}
1528 
1529 	if (ret >= 0)
1530 		ret += sr->done_io;
1531 	else if (sr->done_io)
1532 		ret = sr->done_io;
1533 
1534 	/*
1535 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1536 	 * flushing notif to io_send_zc_cleanup()
1537 	 */
1538 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1539 		io_notif_flush(sr->notif);
1540 		sr->notif = NULL;
1541 		io_req_msg_cleanup(req, 0);
1542 	}
1543 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1544 	return IOU_OK;
1545 }
1546 
1547 void io_sendrecv_fail(struct io_kiocb *req)
1548 {
1549 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1550 
1551 	if (sr->done_io)
1552 		req->cqe.res = sr->done_io;
1553 
1554 	if ((req->flags & REQ_F_NEED_CLEANUP) &&
1555 	    (req->opcode == IORING_OP_SEND_ZC || req->opcode == IORING_OP_SENDMSG_ZC))
1556 		req->cqe.flags |= IORING_CQE_F_MORE;
1557 }
1558 
1559 #define ACCEPT_FLAGS	(IORING_ACCEPT_MULTISHOT | IORING_ACCEPT_DONTWAIT | \
1560 			 IORING_ACCEPT_POLL_FIRST)
1561 
1562 int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1563 {
1564 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1565 
1566 	if (sqe->len || sqe->buf_index)
1567 		return -EINVAL;
1568 
1569 	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1570 	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
1571 	accept->flags = READ_ONCE(sqe->accept_flags);
1572 	accept->nofile = rlimit(RLIMIT_NOFILE);
1573 	accept->iou_flags = READ_ONCE(sqe->ioprio);
1574 	if (accept->iou_flags & ~ACCEPT_FLAGS)
1575 		return -EINVAL;
1576 
1577 	accept->file_slot = READ_ONCE(sqe->file_index);
1578 	if (accept->file_slot) {
1579 		if (accept->flags & SOCK_CLOEXEC)
1580 			return -EINVAL;
1581 		if (accept->iou_flags & IORING_ACCEPT_MULTISHOT &&
1582 		    accept->file_slot != IORING_FILE_INDEX_ALLOC)
1583 			return -EINVAL;
1584 	}
1585 	if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1586 		return -EINVAL;
1587 	if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
1588 		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1589 	if (accept->iou_flags & IORING_ACCEPT_MULTISHOT)
1590 		req->flags |= REQ_F_APOLL_MULTISHOT;
1591 	if (accept->iou_flags & IORING_ACCEPT_DONTWAIT)
1592 		req->flags |= REQ_F_NOWAIT;
1593 	return 0;
1594 }
1595 
1596 int io_accept(struct io_kiocb *req, unsigned int issue_flags)
1597 {
1598 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1599 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1600 	bool fixed = !!accept->file_slot;
1601 	struct proto_accept_arg arg = {
1602 		.flags = force_nonblock ? O_NONBLOCK : 0,
1603 	};
1604 	struct file *file;
1605 	unsigned cflags;
1606 	int ret, fd;
1607 
1608 	if (!(req->flags & REQ_F_POLLED) &&
1609 	    accept->iou_flags & IORING_ACCEPT_POLL_FIRST)
1610 		return -EAGAIN;
1611 
1612 retry:
1613 	if (!fixed) {
1614 		fd = __get_unused_fd_flags(accept->flags, accept->nofile);
1615 		if (unlikely(fd < 0))
1616 			return fd;
1617 	}
1618 	arg.err = 0;
1619 	arg.is_empty = -1;
1620 	file = do_accept(req->file, &arg, accept->addr, accept->addr_len,
1621 			 accept->flags);
1622 	if (IS_ERR(file)) {
1623 		if (!fixed)
1624 			put_unused_fd(fd);
1625 		ret = PTR_ERR(file);
1626 		if (ret == -EAGAIN && force_nonblock &&
1627 		    !(accept->iou_flags & IORING_ACCEPT_DONTWAIT))
1628 			return IOU_RETRY;
1629 
1630 		if (ret == -ERESTARTSYS)
1631 			ret = -EINTR;
1632 	} else if (!fixed) {
1633 		fd_install(fd, file);
1634 		ret = fd;
1635 	} else {
1636 		ret = io_fixed_fd_install(req, issue_flags, file,
1637 						accept->file_slot);
1638 	}
1639 
1640 	cflags = 0;
1641 	if (!arg.is_empty)
1642 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
1643 
1644 	if (ret >= 0 && (req->flags & REQ_F_APOLL_MULTISHOT) &&
1645 	    io_req_post_cqe(req, ret, cflags | IORING_CQE_F_MORE)) {
1646 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || arg.is_empty == -1)
1647 			goto retry;
1648 		return IOU_RETRY;
1649 	}
1650 
1651 	io_req_set_res(req, ret, cflags);
1652 	if (ret < 0)
1653 		req_set_fail(req);
1654 	return IOU_COMPLETE;
1655 }
1656 
1657 int io_socket_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1658 {
1659 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1660 
1661 	if (sqe->addr || sqe->rw_flags || sqe->buf_index)
1662 		return -EINVAL;
1663 
1664 	sock->domain = READ_ONCE(sqe->fd);
1665 	sock->type = READ_ONCE(sqe->off);
1666 	sock->protocol = READ_ONCE(sqe->len);
1667 	sock->file_slot = READ_ONCE(sqe->file_index);
1668 	sock->nofile = rlimit(RLIMIT_NOFILE);
1669 
1670 	sock->flags = sock->type & ~SOCK_TYPE_MASK;
1671 	if (sock->file_slot && (sock->flags & SOCK_CLOEXEC))
1672 		return -EINVAL;
1673 	if (sock->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1674 		return -EINVAL;
1675 	return 0;
1676 }
1677 
1678 int io_socket(struct io_kiocb *req, unsigned int issue_flags)
1679 {
1680 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1681 	bool fixed = !!sock->file_slot;
1682 	struct file *file;
1683 	int ret, fd;
1684 
1685 	if (!fixed) {
1686 		fd = __get_unused_fd_flags(sock->flags, sock->nofile);
1687 		if (unlikely(fd < 0))
1688 			return fd;
1689 	}
1690 	file = __sys_socket_file(sock->domain, sock->type, sock->protocol);
1691 	if (IS_ERR(file)) {
1692 		if (!fixed)
1693 			put_unused_fd(fd);
1694 		ret = PTR_ERR(file);
1695 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1696 			return -EAGAIN;
1697 		if (ret == -ERESTARTSYS)
1698 			ret = -EINTR;
1699 		req_set_fail(req);
1700 	} else if (!fixed) {
1701 		fd_install(fd, file);
1702 		ret = fd;
1703 	} else {
1704 		ret = io_fixed_fd_install(req, issue_flags, file,
1705 					    sock->file_slot);
1706 	}
1707 	io_req_set_res(req, ret, 0);
1708 	return IOU_OK;
1709 }
1710 
1711 int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1712 {
1713 	struct io_connect *conn = io_kiocb_to_cmd(req, struct io_connect);
1714 	struct io_async_msghdr *io;
1715 
1716 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1717 		return -EINVAL;
1718 
1719 	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1720 	conn->addr_len =  READ_ONCE(sqe->addr2);
1721 	conn->in_progress = conn->seen_econnaborted = false;
1722 
1723 	io = io_msg_alloc_async(req);
1724 	if (unlikely(!io))
1725 		return -ENOMEM;
1726 
1727 	return move_addr_to_kernel(conn->addr, conn->addr_len, &io->addr);
1728 }
1729 
1730 int io_connect(struct io_kiocb *req, unsigned int issue_flags)
1731 {
1732 	struct io_connect *connect = io_kiocb_to_cmd(req, struct io_connect);
1733 	struct io_async_msghdr *io = req->async_data;
1734 	unsigned file_flags;
1735 	int ret;
1736 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1737 
1738 	if (unlikely(req->flags & REQ_F_FAIL)) {
1739 		ret = -ECONNRESET;
1740 		goto out;
1741 	}
1742 
1743 	file_flags = force_nonblock ? O_NONBLOCK : 0;
1744 
1745 	ret = __sys_connect_file(req->file, &io->addr, connect->addr_len,
1746 				 file_flags);
1747 	if ((ret == -EAGAIN || ret == -EINPROGRESS || ret == -ECONNABORTED)
1748 	    && force_nonblock) {
1749 		if (ret == -EINPROGRESS) {
1750 			connect->in_progress = true;
1751 		} else if (ret == -ECONNABORTED) {
1752 			if (connect->seen_econnaborted)
1753 				goto out;
1754 			connect->seen_econnaborted = true;
1755 		}
1756 		return -EAGAIN;
1757 	}
1758 	if (connect->in_progress) {
1759 		/*
1760 		 * At least bluetooth will return -EBADFD on a re-connect
1761 		 * attempt, and it's (supposedly) also valid to get -EISCONN
1762 		 * which means the previous result is good. For both of these,
1763 		 * grab the sock_error() and use that for the completion.
1764 		 */
1765 		if (ret == -EBADFD || ret == -EISCONN)
1766 			ret = sock_error(sock_from_file(req->file)->sk);
1767 	}
1768 	if (ret == -ERESTARTSYS)
1769 		ret = -EINTR;
1770 out:
1771 	if (ret < 0)
1772 		req_set_fail(req);
1773 	io_req_msg_cleanup(req, issue_flags);
1774 	io_req_set_res(req, ret, 0);
1775 	return IOU_OK;
1776 }
1777 
1778 int io_bind_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1779 {
1780 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1781 	struct sockaddr __user *uaddr;
1782 	struct io_async_msghdr *io;
1783 
1784 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1785 		return -EINVAL;
1786 
1787 	uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1788 	bind->addr_len =  READ_ONCE(sqe->addr2);
1789 
1790 	io = io_msg_alloc_async(req);
1791 	if (unlikely(!io))
1792 		return -ENOMEM;
1793 	return move_addr_to_kernel(uaddr, bind->addr_len, &io->addr);
1794 }
1795 
1796 int io_bind(struct io_kiocb *req, unsigned int issue_flags)
1797 {
1798 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1799 	struct io_async_msghdr *io = req->async_data;
1800 	struct socket *sock;
1801 	int ret;
1802 
1803 	sock = sock_from_file(req->file);
1804 	if (unlikely(!sock))
1805 		return -ENOTSOCK;
1806 
1807 	ret = __sys_bind_socket(sock, &io->addr, bind->addr_len);
1808 	if (ret < 0)
1809 		req_set_fail(req);
1810 	io_req_set_res(req, ret, 0);
1811 	return 0;
1812 }
1813 
1814 int io_listen_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1815 {
1816 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1817 
1818 	if (sqe->addr || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in || sqe->addr2)
1819 		return -EINVAL;
1820 
1821 	listen->backlog = READ_ONCE(sqe->len);
1822 	return 0;
1823 }
1824 
1825 int io_listen(struct io_kiocb *req, unsigned int issue_flags)
1826 {
1827 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1828 	struct socket *sock;
1829 	int ret;
1830 
1831 	sock = sock_from_file(req->file);
1832 	if (unlikely(!sock))
1833 		return -ENOTSOCK;
1834 
1835 	ret = __sys_listen_socket(sock, listen->backlog);
1836 	if (ret < 0)
1837 		req_set_fail(req);
1838 	io_req_set_res(req, ret, 0);
1839 	return 0;
1840 }
1841 
1842 void io_netmsg_cache_free(const void *entry)
1843 {
1844 	struct io_async_msghdr *kmsg = (struct io_async_msghdr *) entry;
1845 
1846 	io_vec_free(&kmsg->vec);
1847 	kfree(kmsg);
1848 }
1849 #endif
1850