xref: /linux/io_uring/net.c (revision ea8d7647f9ddf1f81e2027ed305299797299aa03)
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 int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
101 {
102 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
103 
104 	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
105 		     sqe->buf_index || sqe->splice_fd_in))
106 		return -EINVAL;
107 
108 	shutdown->how = READ_ONCE(sqe->len);
109 	req->flags |= REQ_F_FORCE_ASYNC;
110 	return 0;
111 }
112 
113 int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
114 {
115 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
116 	struct socket *sock;
117 	int ret;
118 
119 	WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
120 
121 	sock = sock_from_file(req->file);
122 	if (unlikely(!sock))
123 		return -ENOTSOCK;
124 
125 	ret = __sys_shutdown_sock(sock, shutdown->how);
126 	io_req_set_res(req, ret, 0);
127 	return IOU_OK;
128 }
129 
130 static bool io_net_retry(struct socket *sock, int flags)
131 {
132 	if (!(flags & MSG_WAITALL))
133 		return false;
134 	return sock->type == SOCK_STREAM || sock->type == SOCK_SEQPACKET;
135 }
136 
137 static void io_netmsg_iovec_free(struct io_async_msghdr *kmsg)
138 {
139 	if (kmsg->vec.iovec)
140 		io_vec_free(&kmsg->vec);
141 }
142 
143 static void io_netmsg_recycle(struct io_kiocb *req, unsigned int issue_flags)
144 {
145 	struct io_async_msghdr *hdr = req->async_data;
146 
147 	/* can't recycle, ensure we free the iovec if we have one */
148 	if (unlikely(issue_flags & IO_URING_F_UNLOCKED)) {
149 		io_netmsg_iovec_free(hdr);
150 		return;
151 	}
152 
153 	/* Let normal cleanup path reap it if we fail adding to the cache */
154 	io_alloc_cache_vec_kasan(&hdr->vec);
155 	if (hdr->vec.nr > IO_VEC_CACHE_SOFT_CAP)
156 		io_vec_free(&hdr->vec);
157 
158 	if (io_alloc_cache_put(&req->ctx->netmsg_cache, hdr)) {
159 		req->async_data = NULL;
160 		req->flags &= ~(REQ_F_ASYNC_DATA|REQ_F_NEED_CLEANUP);
161 	}
162 }
163 
164 static struct io_async_msghdr *io_msg_alloc_async(struct io_kiocb *req)
165 {
166 	struct io_ring_ctx *ctx = req->ctx;
167 	struct io_async_msghdr *hdr;
168 
169 	hdr = io_uring_alloc_async_data(&ctx->netmsg_cache, req);
170 	if (!hdr)
171 		return NULL;
172 
173 	/* If the async data was cached, we might have an iov cached inside. */
174 	if (hdr->vec.iovec)
175 		req->flags |= REQ_F_NEED_CLEANUP;
176 	return hdr;
177 }
178 
179 /* assign new iovec to kmsg, if we need to */
180 static void io_net_vec_assign(struct io_kiocb *req, struct io_async_msghdr *kmsg,
181 			     struct iovec *iov)
182 {
183 	if (iov) {
184 		req->flags |= REQ_F_NEED_CLEANUP;
185 		io_vec_reset_iovec(&kmsg->vec, iov, kmsg->msg.msg_iter.nr_segs);
186 	}
187 }
188 
189 static inline void io_mshot_prep_retry(struct io_kiocb *req,
190 				       struct io_async_msghdr *kmsg)
191 {
192 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
193 
194 	req->flags &= ~REQ_F_BL_EMPTY;
195 	sr->done_io = 0;
196 	sr->retry = false;
197 	sr->len = 0; /* get from the provided buffer */
198 	req->buf_index = sr->buf_group;
199 }
200 
201 static int io_net_import_vec(struct io_kiocb *req, struct io_async_msghdr *iomsg,
202 			     const struct iovec __user *uiov, unsigned uvec_seg,
203 			     int ddir)
204 {
205 	struct iovec *iov;
206 	int ret, nr_segs;
207 
208 	if (iomsg->vec.iovec) {
209 		nr_segs = iomsg->vec.nr;
210 		iov = iomsg->vec.iovec;
211 	} else {
212 		nr_segs = 1;
213 		iov = &iomsg->fast_iov;
214 	}
215 
216 	ret = __import_iovec(ddir, uiov, uvec_seg, nr_segs, &iov,
217 			     &iomsg->msg.msg_iter, io_is_compat(req->ctx));
218 	if (unlikely(ret < 0))
219 		return ret;
220 	io_net_vec_assign(req, iomsg, iov);
221 	return 0;
222 }
223 
224 static int io_compat_msg_copy_hdr(struct io_kiocb *req,
225 				  struct io_async_msghdr *iomsg,
226 				  struct compat_msghdr *msg, int ddir,
227 				  struct sockaddr __user **save_addr)
228 {
229 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
230 	struct compat_iovec __user *uiov;
231 	int ret;
232 
233 	if (copy_from_user(msg, sr->umsg_compat, sizeof(*msg)))
234 		return -EFAULT;
235 
236 	ret = __get_compat_msghdr(&iomsg->msg, msg, save_addr);
237 	if (ret)
238 		return ret;
239 
240 	uiov = compat_ptr(msg->msg_iov);
241 	if (req->flags & REQ_F_BUFFER_SELECT) {
242 		if (msg->msg_iovlen == 0) {
243 			sr->len = 0;
244 		} else if (msg->msg_iovlen > 1) {
245 			return -EINVAL;
246 		} else {
247 			struct compat_iovec tmp_iov;
248 
249 			if (copy_from_user(&tmp_iov, uiov, sizeof(tmp_iov)))
250 				return -EFAULT;
251 			sr->len = tmp_iov.iov_len;
252 		}
253 	}
254 	return 0;
255 }
256 
257 static int io_copy_msghdr_from_user(struct user_msghdr *msg,
258 				    struct user_msghdr __user *umsg)
259 {
260 	if (!user_access_begin(umsg, sizeof(*umsg)))
261 		return -EFAULT;
262 	unsafe_get_user(msg->msg_name, &umsg->msg_name, ua_end);
263 	unsafe_get_user(msg->msg_namelen, &umsg->msg_namelen, ua_end);
264 	unsafe_get_user(msg->msg_iov, &umsg->msg_iov, ua_end);
265 	unsafe_get_user(msg->msg_iovlen, &umsg->msg_iovlen, ua_end);
266 	unsafe_get_user(msg->msg_control, &umsg->msg_control, ua_end);
267 	unsafe_get_user(msg->msg_controllen, &umsg->msg_controllen, ua_end);
268 	user_access_end();
269 	return 0;
270 ua_end:
271 	user_access_end();
272 	return -EFAULT;
273 }
274 
275 static int io_msg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg,
276 			   struct user_msghdr *msg, int ddir,
277 			   struct sockaddr __user **save_addr)
278 {
279 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
280 	struct user_msghdr __user *umsg = sr->umsg;
281 	int ret;
282 
283 	iomsg->msg.msg_name = &iomsg->addr;
284 	iomsg->msg.msg_iter.nr_segs = 0;
285 
286 	if (io_is_compat(req->ctx)) {
287 		struct compat_msghdr cmsg;
288 
289 		ret = io_compat_msg_copy_hdr(req, iomsg, &cmsg, ddir, save_addr);
290 		if (ret)
291 			return ret;
292 
293 		memset(msg, 0, sizeof(*msg));
294 		msg->msg_namelen = cmsg.msg_namelen;
295 		msg->msg_controllen = cmsg.msg_controllen;
296 		msg->msg_iov = compat_ptr(cmsg.msg_iov);
297 		msg->msg_iovlen = cmsg.msg_iovlen;
298 		return 0;
299 	}
300 
301 	ret = io_copy_msghdr_from_user(msg, umsg);
302 	if (unlikely(ret))
303 		return ret;
304 
305 	msg->msg_flags = 0;
306 
307 	ret = __copy_msghdr(&iomsg->msg, msg, save_addr);
308 	if (ret)
309 		return ret;
310 
311 	if (req->flags & REQ_F_BUFFER_SELECT) {
312 		if (msg->msg_iovlen == 0) {
313 			sr->len = 0;
314 		} else if (msg->msg_iovlen > 1) {
315 			return -EINVAL;
316 		} else {
317 			struct iovec __user *uiov = msg->msg_iov;
318 			struct iovec tmp_iov;
319 
320 			if (copy_from_user(&tmp_iov, uiov, sizeof(tmp_iov)))
321 				return -EFAULT;
322 			sr->len = tmp_iov.iov_len;
323 		}
324 	}
325 	return 0;
326 }
327 
328 static int io_sendmsg_copy_hdr(struct io_kiocb *req,
329 			       struct io_async_msghdr *iomsg)
330 {
331 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
332 	struct user_msghdr msg;
333 	int ret;
334 
335 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_SOURCE, NULL);
336 	if (unlikely(ret))
337 		return ret;
338 
339 	if (!(req->flags & REQ_F_BUFFER_SELECT))
340 		ret = io_net_import_vec(req, iomsg, msg.msg_iov, msg.msg_iovlen,
341 					ITER_SOURCE);
342 	/* save msg_control as sys_sendmsg() overwrites it */
343 	sr->msg_control = iomsg->msg.msg_control_user;
344 	return ret;
345 }
346 
347 void io_sendmsg_recvmsg_cleanup(struct io_kiocb *req)
348 {
349 	struct io_async_msghdr *io = req->async_data;
350 
351 	io_netmsg_iovec_free(io);
352 }
353 
354 static int io_send_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
355 {
356 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
357 	struct io_async_msghdr *kmsg = req->async_data;
358 	void __user *addr;
359 	u16 addr_len;
360 	int ret;
361 
362 	sr->buf = u64_to_user_ptr(READ_ONCE(sqe->addr));
363 
364 	if (READ_ONCE(sqe->__pad3[0]))
365 		return -EINVAL;
366 
367 	kmsg->msg.msg_name = NULL;
368 	kmsg->msg.msg_namelen = 0;
369 	kmsg->msg.msg_control = NULL;
370 	kmsg->msg.msg_controllen = 0;
371 	kmsg->msg.msg_ubuf = NULL;
372 
373 	addr = u64_to_user_ptr(READ_ONCE(sqe->addr2));
374 	addr_len = READ_ONCE(sqe->addr_len);
375 	if (addr) {
376 		ret = move_addr_to_kernel(addr, addr_len, &kmsg->addr);
377 		if (unlikely(ret < 0))
378 			return ret;
379 		kmsg->msg.msg_name = &kmsg->addr;
380 		kmsg->msg.msg_namelen = addr_len;
381 	}
382 	if (!io_do_buffer_select(req)) {
383 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
384 				  &kmsg->msg.msg_iter);
385 		if (unlikely(ret < 0))
386 			return ret;
387 	}
388 	return 0;
389 }
390 
391 static int io_sendmsg_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
392 {
393 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
394 	struct io_async_msghdr *kmsg = req->async_data;
395 
396 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
397 
398 	return io_sendmsg_copy_hdr(req, kmsg);
399 }
400 
401 static int io_sendmsg_zc_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
402 {
403 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
404 	struct io_async_msghdr *kmsg = req->async_data;
405 	struct user_msghdr msg;
406 	int ret;
407 
408 	if (!(sr->flags & IORING_RECVSEND_FIXED_BUF))
409 		return io_sendmsg_setup(req, sqe);
410 
411 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
412 
413 	ret = io_msg_copy_hdr(req, kmsg, &msg, ITER_SOURCE, NULL);
414 	if (unlikely(ret))
415 		return ret;
416 	sr->msg_control = kmsg->msg.msg_control_user;
417 	kmsg->msg.msg_iter.nr_segs = msg.msg_iovlen;
418 
419 	return io_prep_reg_iovec(req, &kmsg->vec, msg.msg_iov, msg.msg_iovlen);
420 }
421 
422 #define SENDMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_BUNDLE)
423 
424 int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
425 {
426 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
427 
428 	sr->done_io = 0;
429 	sr->retry = false;
430 
431 	if (req->opcode != IORING_OP_SEND) {
432 		if (sqe->addr2 || sqe->file_index)
433 			return -EINVAL;
434 	}
435 
436 	sr->len = READ_ONCE(sqe->len);
437 	sr->flags = READ_ONCE(sqe->ioprio);
438 	if (sr->flags & ~SENDMSG_FLAGS)
439 		return -EINVAL;
440 	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
441 	if (sr->msg_flags & MSG_DONTWAIT)
442 		req->flags |= REQ_F_NOWAIT;
443 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
444 		if (req->opcode == IORING_OP_SENDMSG)
445 			return -EINVAL;
446 		if (!(req->flags & REQ_F_BUFFER_SELECT))
447 			return -EINVAL;
448 		sr->msg_flags |= MSG_WAITALL;
449 		sr->buf_group = req->buf_index;
450 		req->buf_list = NULL;
451 		req->flags |= REQ_F_MULTISHOT;
452 	}
453 
454 	if (io_is_compat(req->ctx))
455 		sr->msg_flags |= MSG_CMSG_COMPAT;
456 
457 	if (unlikely(!io_msg_alloc_async(req)))
458 		return -ENOMEM;
459 	if (req->opcode != IORING_OP_SENDMSG)
460 		return io_send_setup(req, sqe);
461 	return io_sendmsg_setup(req, sqe);
462 }
463 
464 static void io_req_msg_cleanup(struct io_kiocb *req,
465 			       unsigned int issue_flags)
466 {
467 	io_netmsg_recycle(req, issue_flags);
468 }
469 
470 /*
471  * For bundle completions, we need to figure out how many segments we consumed.
472  * A bundle could be using a single ITER_UBUF if that's all we mapped, or it
473  * could be using an ITER_IOVEC. If the latter, then if we consumed all of
474  * the segments, then it's a trivial questiont o answer. If we have residual
475  * data in the iter, then loop the segments to figure out how much we
476  * transferred.
477  */
478 static int io_bundle_nbufs(struct io_async_msghdr *kmsg, int ret)
479 {
480 	struct iovec *iov;
481 	int nbufs;
482 
483 	/* no data is always zero segments, and a ubuf is always 1 segment */
484 	if (ret <= 0)
485 		return 0;
486 	if (iter_is_ubuf(&kmsg->msg.msg_iter))
487 		return 1;
488 
489 	iov = kmsg->vec.iovec;
490 	if (!iov)
491 		iov = &kmsg->fast_iov;
492 
493 	/* if all data was transferred, it's basic pointer math */
494 	if (!iov_iter_count(&kmsg->msg.msg_iter))
495 		return iter_iov(&kmsg->msg.msg_iter) - iov;
496 
497 	/* short transfer, count segments */
498 	nbufs = 0;
499 	do {
500 		int this_len = min_t(int, iov[nbufs].iov_len, ret);
501 
502 		nbufs++;
503 		ret -= this_len;
504 	} while (ret);
505 
506 	return nbufs;
507 }
508 
509 static inline bool io_send_finish(struct io_kiocb *req, int *ret,
510 				  struct io_async_msghdr *kmsg,
511 				  unsigned issue_flags)
512 {
513 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
514 	bool bundle_finished = *ret <= 0;
515 	unsigned int cflags;
516 
517 	if (!(sr->flags & IORING_RECVSEND_BUNDLE)) {
518 		cflags = io_put_kbuf(req, *ret, issue_flags);
519 		goto finish;
520 	}
521 
522 	cflags = io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret), issue_flags);
523 
524 	if (bundle_finished || req->flags & REQ_F_BL_EMPTY)
525 		goto finish;
526 
527 	/*
528 	 * Fill CQE for this receive and see if we should keep trying to
529 	 * receive from this socket.
530 	 */
531 	if (io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
532 		io_mshot_prep_retry(req, kmsg);
533 		return false;
534 	}
535 
536 	/* Otherwise stop bundle and use the current result. */
537 finish:
538 	io_req_set_res(req, *ret, cflags);
539 	*ret = IOU_OK;
540 	return true;
541 }
542 
543 int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
544 {
545 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
546 	struct io_async_msghdr *kmsg = req->async_data;
547 	struct socket *sock;
548 	unsigned flags;
549 	int min_ret = 0;
550 	int ret;
551 
552 	sock = sock_from_file(req->file);
553 	if (unlikely(!sock))
554 		return -ENOTSOCK;
555 
556 	if (!(req->flags & REQ_F_POLLED) &&
557 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
558 		return -EAGAIN;
559 
560 	flags = sr->msg_flags;
561 	if (issue_flags & IO_URING_F_NONBLOCK)
562 		flags |= MSG_DONTWAIT;
563 	if (flags & MSG_WAITALL)
564 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
565 
566 	kmsg->msg.msg_control_user = sr->msg_control;
567 
568 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
569 
570 	if (ret < min_ret) {
571 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
572 			return -EAGAIN;
573 		if (ret > 0 && io_net_retry(sock, flags)) {
574 			kmsg->msg.msg_controllen = 0;
575 			kmsg->msg.msg_control = NULL;
576 			sr->done_io += ret;
577 			req->flags |= REQ_F_BL_NO_RECYCLE;
578 			return -EAGAIN;
579 		}
580 		if (ret == -ERESTARTSYS)
581 			ret = -EINTR;
582 		req_set_fail(req);
583 	}
584 	io_req_msg_cleanup(req, issue_flags);
585 	if (ret >= 0)
586 		ret += sr->done_io;
587 	else if (sr->done_io)
588 		ret = sr->done_io;
589 	io_req_set_res(req, ret, 0);
590 	return IOU_OK;
591 }
592 
593 static int io_send_select_buffer(struct io_kiocb *req, unsigned int issue_flags,
594 				 struct io_async_msghdr *kmsg)
595 {
596 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
597 
598 	int ret;
599 	struct buf_sel_arg arg = {
600 		.iovs = &kmsg->fast_iov,
601 		.max_len = min_not_zero(sr->len, INT_MAX),
602 		.nr_iovs = 1,
603 	};
604 
605 	if (kmsg->vec.iovec) {
606 		arg.nr_iovs = kmsg->vec.nr;
607 		arg.iovs = kmsg->vec.iovec;
608 		arg.mode = KBUF_MODE_FREE;
609 	}
610 
611 	if (!(sr->flags & IORING_RECVSEND_BUNDLE))
612 		arg.nr_iovs = 1;
613 	else
614 		arg.mode |= KBUF_MODE_EXPAND;
615 
616 	ret = io_buffers_select(req, &arg, issue_flags);
617 	if (unlikely(ret < 0))
618 		return ret;
619 
620 	if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->vec.iovec) {
621 		kmsg->vec.nr = ret;
622 		kmsg->vec.iovec = arg.iovs;
623 		req->flags |= REQ_F_NEED_CLEANUP;
624 	}
625 	sr->len = arg.out_len;
626 
627 	if (ret == 1) {
628 		sr->buf = arg.iovs[0].iov_base;
629 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
630 					&kmsg->msg.msg_iter);
631 		if (unlikely(ret))
632 			return ret;
633 	} else {
634 		iov_iter_init(&kmsg->msg.msg_iter, ITER_SOURCE,
635 				arg.iovs, ret, arg.out_len);
636 	}
637 
638 	return 0;
639 }
640 
641 int io_send(struct io_kiocb *req, unsigned int issue_flags)
642 {
643 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
644 	struct io_async_msghdr *kmsg = req->async_data;
645 	struct socket *sock;
646 	unsigned flags;
647 	int min_ret = 0;
648 	int ret;
649 
650 	sock = sock_from_file(req->file);
651 	if (unlikely(!sock))
652 		return -ENOTSOCK;
653 
654 	if (!(req->flags & REQ_F_POLLED) &&
655 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
656 		return -EAGAIN;
657 
658 	flags = sr->msg_flags;
659 	if (issue_flags & IO_URING_F_NONBLOCK)
660 		flags |= MSG_DONTWAIT;
661 
662 retry_bundle:
663 	if (io_do_buffer_select(req)) {
664 		ret = io_send_select_buffer(req, issue_flags, kmsg);
665 		if (ret)
666 			return ret;
667 	}
668 
669 	/*
670 	 * If MSG_WAITALL is set, or this is a bundle send, then we need
671 	 * the full amount. If just bundle is set, if we do a short send
672 	 * then we complete the bundle sequence rather than continue on.
673 	 */
674 	if (flags & MSG_WAITALL || sr->flags & IORING_RECVSEND_BUNDLE)
675 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
676 
677 	flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
678 	kmsg->msg.msg_flags = flags;
679 	ret = sock_sendmsg(sock, &kmsg->msg);
680 	if (ret < min_ret) {
681 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
682 			return -EAGAIN;
683 
684 		if (ret > 0 && io_net_retry(sock, flags)) {
685 			sr->len -= ret;
686 			sr->buf += ret;
687 			sr->done_io += ret;
688 			req->flags |= REQ_F_BL_NO_RECYCLE;
689 			return -EAGAIN;
690 		}
691 		if (ret == -ERESTARTSYS)
692 			ret = -EINTR;
693 		req_set_fail(req);
694 	}
695 	if (ret >= 0)
696 		ret += sr->done_io;
697 	else if (sr->done_io)
698 		ret = sr->done_io;
699 
700 	if (!io_send_finish(req, &ret, kmsg, issue_flags))
701 		goto retry_bundle;
702 
703 	io_req_msg_cleanup(req, issue_flags);
704 	return ret;
705 }
706 
707 static int io_recvmsg_mshot_prep(struct io_kiocb *req,
708 				 struct io_async_msghdr *iomsg,
709 				 int namelen, size_t controllen)
710 {
711 	if ((req->flags & (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) ==
712 			  (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) {
713 		int hdr;
714 
715 		if (unlikely(namelen < 0))
716 			return -EOVERFLOW;
717 		if (check_add_overflow(sizeof(struct io_uring_recvmsg_out),
718 					namelen, &hdr))
719 			return -EOVERFLOW;
720 		if (check_add_overflow(hdr, controllen, &hdr))
721 			return -EOVERFLOW;
722 
723 		iomsg->namelen = namelen;
724 		iomsg->controllen = controllen;
725 		return 0;
726 	}
727 
728 	return 0;
729 }
730 
731 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
732 			       struct io_async_msghdr *iomsg)
733 {
734 	struct user_msghdr msg;
735 	int ret;
736 
737 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_DEST, &iomsg->uaddr);
738 	if (unlikely(ret))
739 		return ret;
740 
741 	if (!(req->flags & REQ_F_BUFFER_SELECT)) {
742 		ret = io_net_import_vec(req, iomsg, msg.msg_iov, msg.msg_iovlen,
743 					ITER_DEST);
744 		if (unlikely(ret))
745 			return ret;
746 	}
747 	return io_recvmsg_mshot_prep(req, iomsg, msg.msg_namelen,
748 					msg.msg_controllen);
749 }
750 
751 static int io_recvmsg_prep_setup(struct io_kiocb *req)
752 {
753 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
754 	struct io_async_msghdr *kmsg;
755 	int ret;
756 
757 	kmsg = io_msg_alloc_async(req);
758 	if (unlikely(!kmsg))
759 		return -ENOMEM;
760 
761 	if (req->opcode == IORING_OP_RECV) {
762 		kmsg->msg.msg_name = NULL;
763 		kmsg->msg.msg_namelen = 0;
764 		kmsg->msg.msg_inq = 0;
765 		kmsg->msg.msg_control = NULL;
766 		kmsg->msg.msg_get_inq = 1;
767 		kmsg->msg.msg_controllen = 0;
768 		kmsg->msg.msg_iocb = NULL;
769 		kmsg->msg.msg_ubuf = NULL;
770 
771 		if (!io_do_buffer_select(req)) {
772 			ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
773 					  &kmsg->msg.msg_iter);
774 			if (unlikely(ret))
775 				return ret;
776 		}
777 		return 0;
778 	}
779 
780 	return io_recvmsg_copy_hdr(req, kmsg);
781 }
782 
783 #define RECVMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT | \
784 			IORING_RECVSEND_BUNDLE)
785 
786 int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
787 {
788 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
789 
790 	sr->done_io = 0;
791 	sr->retry = false;
792 
793 	if (unlikely(sqe->file_index || sqe->addr2))
794 		return -EINVAL;
795 
796 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
797 	sr->len = READ_ONCE(sqe->len);
798 	sr->flags = READ_ONCE(sqe->ioprio);
799 	if (sr->flags & ~RECVMSG_FLAGS)
800 		return -EINVAL;
801 	sr->msg_flags = READ_ONCE(sqe->msg_flags);
802 	if (sr->msg_flags & MSG_DONTWAIT)
803 		req->flags |= REQ_F_NOWAIT;
804 	if (sr->msg_flags & MSG_ERRQUEUE)
805 		req->flags |= REQ_F_CLEAR_POLLIN;
806 	if (req->flags & REQ_F_BUFFER_SELECT) {
807 		/*
808 		 * Store the buffer group for this multishot receive separately,
809 		 * as if we end up doing an io-wq based issue that selects a
810 		 * buffer, it has to be committed immediately and that will
811 		 * clear ->buf_list. This means we lose the link to the buffer
812 		 * list, and the eventual buffer put on completion then cannot
813 		 * restore it.
814 		 */
815 		sr->buf_group = req->buf_index;
816 		req->buf_list = NULL;
817 	}
818 	if (sr->flags & IORING_RECV_MULTISHOT) {
819 		if (!(req->flags & REQ_F_BUFFER_SELECT))
820 			return -EINVAL;
821 		if (sr->msg_flags & MSG_WAITALL)
822 			return -EINVAL;
823 		if (req->opcode == IORING_OP_RECV && sr->len)
824 			return -EINVAL;
825 		req->flags |= REQ_F_APOLL_MULTISHOT;
826 	}
827 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
828 		if (req->opcode == IORING_OP_RECVMSG)
829 			return -EINVAL;
830 	}
831 
832 	if (io_is_compat(req->ctx))
833 		sr->msg_flags |= MSG_CMSG_COMPAT;
834 
835 	sr->nr_multishot_loops = 0;
836 	return io_recvmsg_prep_setup(req);
837 }
838 
839 /* bits to clear in old and inherit in new cflags on bundle retry */
840 #define CQE_F_MASK	(IORING_CQE_F_SOCK_NONEMPTY|IORING_CQE_F_MORE)
841 
842 /*
843  * Finishes io_recv and io_recvmsg.
844  *
845  * Returns true if it is actually finished, or false if it should run
846  * again (for multishot).
847  */
848 static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
849 				  struct io_async_msghdr *kmsg,
850 				  bool mshot_finished, unsigned issue_flags)
851 {
852 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
853 	unsigned int cflags = 0;
854 
855 	if (kmsg->msg.msg_inq > 0)
856 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
857 
858 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
859 		cflags |= io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret),
860 				      issue_flags);
861 		if (sr->retry)
862 			cflags = req->cqe.flags | (cflags & CQE_F_MASK);
863 		/* bundle with no more immediate buffers, we're done */
864 		if (req->flags & REQ_F_BL_EMPTY)
865 			goto finish;
866 		/* if more is available, retry and append to this one */
867 		if (!sr->retry && kmsg->msg.msg_inq > 0 && *ret > 0) {
868 			req->cqe.flags = cflags & ~CQE_F_MASK;
869 			sr->len = kmsg->msg.msg_inq;
870 			sr->done_io += *ret;
871 			sr->retry = true;
872 			return false;
873 		}
874 	} else {
875 		cflags |= io_put_kbuf(req, *ret, issue_flags);
876 	}
877 
878 	/*
879 	 * Fill CQE for this receive and see if we should keep trying to
880 	 * receive from this socket.
881 	 */
882 	if ((req->flags & REQ_F_APOLL_MULTISHOT) && !mshot_finished &&
883 	    io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
884 		*ret = IOU_RETRY;
885 		io_mshot_prep_retry(req, kmsg);
886 		/* Known not-empty or unknown state, retry */
887 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || kmsg->msg.msg_inq < 0) {
888 			if (sr->nr_multishot_loops++ < MULTISHOT_MAX_RETRY)
889 				return false;
890 			/* mshot retries exceeded, force a requeue */
891 			sr->nr_multishot_loops = 0;
892 			if (issue_flags & IO_URING_F_MULTISHOT)
893 				*ret = IOU_REQUEUE;
894 		}
895 		return true;
896 	}
897 
898 	/* Finish the request / stop multishot. */
899 finish:
900 	io_req_set_res(req, *ret, cflags);
901 	*ret = IOU_COMPLETE;
902 	io_req_msg_cleanup(req, issue_flags);
903 	return true;
904 }
905 
906 static int io_recvmsg_prep_multishot(struct io_async_msghdr *kmsg,
907 				     struct io_sr_msg *sr, void __user **buf,
908 				     size_t *len)
909 {
910 	unsigned long ubuf = (unsigned long) *buf;
911 	unsigned long hdr;
912 
913 	hdr = sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
914 		kmsg->controllen;
915 	if (*len < hdr)
916 		return -EFAULT;
917 
918 	if (kmsg->controllen) {
919 		unsigned long control = ubuf + hdr - kmsg->controllen;
920 
921 		kmsg->msg.msg_control_user = (void __user *) control;
922 		kmsg->msg.msg_controllen = kmsg->controllen;
923 	}
924 
925 	sr->buf = *buf; /* stash for later copy */
926 	*buf = (void __user *) (ubuf + hdr);
927 	kmsg->payloadlen = *len = *len - hdr;
928 	return 0;
929 }
930 
931 struct io_recvmsg_multishot_hdr {
932 	struct io_uring_recvmsg_out msg;
933 	struct sockaddr_storage addr;
934 };
935 
936 static int io_recvmsg_multishot(struct socket *sock, struct io_sr_msg *io,
937 				struct io_async_msghdr *kmsg,
938 				unsigned int flags, bool *finished)
939 {
940 	int err;
941 	int copy_len;
942 	struct io_recvmsg_multishot_hdr hdr;
943 
944 	if (kmsg->namelen)
945 		kmsg->msg.msg_name = &hdr.addr;
946 	kmsg->msg.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
947 	kmsg->msg.msg_namelen = 0;
948 
949 	if (sock->file->f_flags & O_NONBLOCK)
950 		flags |= MSG_DONTWAIT;
951 
952 	err = sock_recvmsg(sock, &kmsg->msg, flags);
953 	*finished = err <= 0;
954 	if (err < 0)
955 		return err;
956 
957 	hdr.msg = (struct io_uring_recvmsg_out) {
958 		.controllen = kmsg->controllen - kmsg->msg.msg_controllen,
959 		.flags = kmsg->msg.msg_flags & ~MSG_CMSG_COMPAT
960 	};
961 
962 	hdr.msg.payloadlen = err;
963 	if (err > kmsg->payloadlen)
964 		err = kmsg->payloadlen;
965 
966 	copy_len = sizeof(struct io_uring_recvmsg_out);
967 	if (kmsg->msg.msg_namelen > kmsg->namelen)
968 		copy_len += kmsg->namelen;
969 	else
970 		copy_len += kmsg->msg.msg_namelen;
971 
972 	/*
973 	 *      "fromlen shall refer to the value before truncation.."
974 	 *                      1003.1g
975 	 */
976 	hdr.msg.namelen = kmsg->msg.msg_namelen;
977 
978 	/* ensure that there is no gap between hdr and sockaddr_storage */
979 	BUILD_BUG_ON(offsetof(struct io_recvmsg_multishot_hdr, addr) !=
980 		     sizeof(struct io_uring_recvmsg_out));
981 	if (copy_to_user(io->buf, &hdr, copy_len)) {
982 		*finished = true;
983 		return -EFAULT;
984 	}
985 
986 	return sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
987 			kmsg->controllen + err;
988 }
989 
990 int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
991 {
992 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
993 	struct io_async_msghdr *kmsg = req->async_data;
994 	struct socket *sock;
995 	unsigned flags;
996 	int ret, min_ret = 0;
997 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
998 	bool mshot_finished = true;
999 
1000 	sock = sock_from_file(req->file);
1001 	if (unlikely(!sock))
1002 		return -ENOTSOCK;
1003 
1004 	if (!(req->flags & REQ_F_POLLED) &&
1005 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1006 		return -EAGAIN;
1007 
1008 	flags = sr->msg_flags;
1009 	if (force_nonblock)
1010 		flags |= MSG_DONTWAIT;
1011 
1012 retry_multishot:
1013 	if (io_do_buffer_select(req)) {
1014 		void __user *buf;
1015 		size_t len = sr->len;
1016 
1017 		buf = io_buffer_select(req, &len, issue_flags);
1018 		if (!buf)
1019 			return -ENOBUFS;
1020 
1021 		if (req->flags & REQ_F_APOLL_MULTISHOT) {
1022 			ret = io_recvmsg_prep_multishot(kmsg, sr, &buf, &len);
1023 			if (ret) {
1024 				io_kbuf_recycle(req, issue_flags);
1025 				return ret;
1026 			}
1027 		}
1028 
1029 		iov_iter_ubuf(&kmsg->msg.msg_iter, ITER_DEST, buf, len);
1030 	}
1031 
1032 	kmsg->msg.msg_get_inq = 1;
1033 	kmsg->msg.msg_inq = -1;
1034 	if (req->flags & REQ_F_APOLL_MULTISHOT) {
1035 		ret = io_recvmsg_multishot(sock, sr, kmsg, flags,
1036 					   &mshot_finished);
1037 	} else {
1038 		/* disable partial retry for recvmsg with cmsg attached */
1039 		if (flags & MSG_WAITALL && !kmsg->msg.msg_controllen)
1040 			min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1041 
1042 		ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg,
1043 					 kmsg->uaddr, flags);
1044 	}
1045 
1046 	if (ret < min_ret) {
1047 		if (ret == -EAGAIN && force_nonblock) {
1048 			if (issue_flags & IO_URING_F_MULTISHOT)
1049 				io_kbuf_recycle(req, issue_flags);
1050 
1051 			return IOU_RETRY;
1052 		}
1053 		if (ret > 0 && io_net_retry(sock, flags)) {
1054 			sr->done_io += ret;
1055 			req->flags |= REQ_F_BL_NO_RECYCLE;
1056 			return IOU_RETRY;
1057 		}
1058 		if (ret == -ERESTARTSYS)
1059 			ret = -EINTR;
1060 		req_set_fail(req);
1061 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1062 		req_set_fail(req);
1063 	}
1064 
1065 	if (ret > 0)
1066 		ret += sr->done_io;
1067 	else if (sr->done_io)
1068 		ret = sr->done_io;
1069 	else
1070 		io_kbuf_recycle(req, issue_flags);
1071 
1072 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1073 		goto retry_multishot;
1074 
1075 	return ret;
1076 }
1077 
1078 static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg,
1079 			      size_t *len, unsigned int issue_flags)
1080 {
1081 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1082 	int ret;
1083 
1084 	/*
1085 	 * If the ring isn't locked, then don't use the peek interface
1086 	 * to grab multiple buffers as we will lock/unlock between
1087 	 * this selection and posting the buffers.
1088 	 */
1089 	if (!(issue_flags & IO_URING_F_UNLOCKED) &&
1090 	    sr->flags & IORING_RECVSEND_BUNDLE) {
1091 		struct buf_sel_arg arg = {
1092 			.iovs = &kmsg->fast_iov,
1093 			.nr_iovs = 1,
1094 			.mode = KBUF_MODE_EXPAND,
1095 		};
1096 
1097 		if (kmsg->vec.iovec) {
1098 			arg.nr_iovs = kmsg->vec.nr;
1099 			arg.iovs = kmsg->vec.iovec;
1100 			arg.mode |= KBUF_MODE_FREE;
1101 		}
1102 
1103 		if (kmsg->msg.msg_inq > 0)
1104 			arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq);
1105 
1106 		ret = io_buffers_peek(req, &arg);
1107 		if (unlikely(ret < 0))
1108 			return ret;
1109 
1110 		/* special case 1 vec, can be a fast path */
1111 		if (ret == 1) {
1112 			sr->buf = arg.iovs[0].iov_base;
1113 			sr->len = arg.iovs[0].iov_len;
1114 			goto map_ubuf;
1115 		}
1116 		iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, arg.iovs, ret,
1117 				arg.out_len);
1118 		if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->vec.iovec) {
1119 			kmsg->vec.nr = ret;
1120 			kmsg->vec.iovec = arg.iovs;
1121 			req->flags |= REQ_F_NEED_CLEANUP;
1122 		}
1123 	} else {
1124 		void __user *buf;
1125 
1126 		*len = sr->len;
1127 		buf = io_buffer_select(req, len, issue_flags);
1128 		if (!buf)
1129 			return -ENOBUFS;
1130 		sr->buf = buf;
1131 		sr->len = *len;
1132 map_ubuf:
1133 		ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
1134 				  &kmsg->msg.msg_iter);
1135 		if (unlikely(ret))
1136 			return ret;
1137 	}
1138 
1139 	return 0;
1140 }
1141 
1142 int io_recv(struct io_kiocb *req, unsigned int issue_flags)
1143 {
1144 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1145 	struct io_async_msghdr *kmsg = req->async_data;
1146 	struct socket *sock;
1147 	unsigned flags;
1148 	int ret, min_ret = 0;
1149 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1150 	size_t len = sr->len;
1151 	bool mshot_finished;
1152 
1153 	if (!(req->flags & REQ_F_POLLED) &&
1154 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1155 		return -EAGAIN;
1156 
1157 	sock = sock_from_file(req->file);
1158 	if (unlikely(!sock))
1159 		return -ENOTSOCK;
1160 
1161 	flags = sr->msg_flags;
1162 	if (force_nonblock)
1163 		flags |= MSG_DONTWAIT;
1164 
1165 retry_multishot:
1166 	if (io_do_buffer_select(req)) {
1167 		ret = io_recv_buf_select(req, kmsg, &len, issue_flags);
1168 		if (unlikely(ret)) {
1169 			kmsg->msg.msg_inq = -1;
1170 			goto out_free;
1171 		}
1172 		sr->buf = NULL;
1173 	}
1174 
1175 	kmsg->msg.msg_flags = 0;
1176 	kmsg->msg.msg_inq = -1;
1177 
1178 	if (flags & MSG_WAITALL)
1179 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1180 
1181 	ret = sock_recvmsg(sock, &kmsg->msg, flags);
1182 	if (ret < min_ret) {
1183 		if (ret == -EAGAIN && force_nonblock) {
1184 			if (issue_flags & IO_URING_F_MULTISHOT)
1185 				io_kbuf_recycle(req, issue_flags);
1186 
1187 			return IOU_RETRY;
1188 		}
1189 		if (ret > 0 && io_net_retry(sock, flags)) {
1190 			sr->len -= ret;
1191 			sr->buf += ret;
1192 			sr->done_io += ret;
1193 			req->flags |= REQ_F_BL_NO_RECYCLE;
1194 			return -EAGAIN;
1195 		}
1196 		if (ret == -ERESTARTSYS)
1197 			ret = -EINTR;
1198 		req_set_fail(req);
1199 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1200 out_free:
1201 		req_set_fail(req);
1202 	}
1203 
1204 	mshot_finished = ret <= 0;
1205 	if (ret > 0)
1206 		ret += sr->done_io;
1207 	else if (sr->done_io)
1208 		ret = sr->done_io;
1209 	else
1210 		io_kbuf_recycle(req, issue_flags);
1211 
1212 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1213 		goto retry_multishot;
1214 
1215 	return ret;
1216 }
1217 
1218 int io_recvzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1219 {
1220 	struct io_recvzc *zc = io_kiocb_to_cmd(req, struct io_recvzc);
1221 	unsigned ifq_idx;
1222 
1223 	if (unlikely(sqe->file_index || sqe->addr2 || sqe->addr ||
1224 		     sqe->addr3))
1225 		return -EINVAL;
1226 
1227 	ifq_idx = READ_ONCE(sqe->zcrx_ifq_idx);
1228 	if (ifq_idx != 0)
1229 		return -EINVAL;
1230 	zc->ifq = req->ctx->ifq;
1231 	if (!zc->ifq)
1232 		return -EINVAL;
1233 	zc->len = READ_ONCE(sqe->len);
1234 	zc->flags = READ_ONCE(sqe->ioprio);
1235 	zc->msg_flags = READ_ONCE(sqe->msg_flags);
1236 	if (zc->msg_flags)
1237 		return -EINVAL;
1238 	if (zc->flags & ~(IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT))
1239 		return -EINVAL;
1240 	/* multishot required */
1241 	if (!(zc->flags & IORING_RECV_MULTISHOT))
1242 		return -EINVAL;
1243 	/* All data completions are posted as aux CQEs. */
1244 	req->flags |= REQ_F_APOLL_MULTISHOT;
1245 
1246 	return 0;
1247 }
1248 
1249 int io_recvzc(struct io_kiocb *req, unsigned int issue_flags)
1250 {
1251 	struct io_recvzc *zc = io_kiocb_to_cmd(req, struct io_recvzc);
1252 	struct socket *sock;
1253 	unsigned int len;
1254 	int ret;
1255 
1256 	if (!(req->flags & REQ_F_POLLED) &&
1257 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1258 		return -EAGAIN;
1259 
1260 	sock = sock_from_file(req->file);
1261 	if (unlikely(!sock))
1262 		return -ENOTSOCK;
1263 
1264 	len = zc->len;
1265 	ret = io_zcrx_recv(req, zc->ifq, sock, zc->msg_flags | MSG_DONTWAIT,
1266 			   issue_flags, &zc->len);
1267 	if (len && zc->len == 0) {
1268 		io_req_set_res(req, 0, 0);
1269 
1270 		return IOU_COMPLETE;
1271 	}
1272 	if (unlikely(ret <= 0) && ret != -EAGAIN) {
1273 		if (ret == -ERESTARTSYS)
1274 			ret = -EINTR;
1275 		if (ret == IOU_REQUEUE)
1276 			return IOU_REQUEUE;
1277 
1278 		req_set_fail(req);
1279 		io_req_set_res(req, ret, 0);
1280 		return IOU_COMPLETE;
1281 	}
1282 	return IOU_RETRY;
1283 }
1284 
1285 void io_send_zc_cleanup(struct io_kiocb *req)
1286 {
1287 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1288 	struct io_async_msghdr *io = req->async_data;
1289 
1290 	if (req_has_async_data(req))
1291 		io_netmsg_iovec_free(io);
1292 	if (zc->notif) {
1293 		io_notif_flush(zc->notif);
1294 		zc->notif = NULL;
1295 	}
1296 }
1297 
1298 #define IO_ZC_FLAGS_COMMON (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_FIXED_BUF)
1299 #define IO_ZC_FLAGS_VALID  (IO_ZC_FLAGS_COMMON | IORING_SEND_ZC_REPORT_USAGE)
1300 
1301 int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1302 {
1303 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1304 	struct io_ring_ctx *ctx = req->ctx;
1305 	struct io_kiocb *notif;
1306 
1307 	zc->done_io = 0;
1308 	zc->retry = false;
1309 	req->flags |= REQ_F_POLL_NO_LAZY;
1310 
1311 	if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3)))
1312 		return -EINVAL;
1313 	/* we don't support IOSQE_CQE_SKIP_SUCCESS just yet */
1314 	if (req->flags & REQ_F_CQE_SKIP)
1315 		return -EINVAL;
1316 
1317 	notif = zc->notif = io_alloc_notif(ctx);
1318 	if (!notif)
1319 		return -ENOMEM;
1320 	notif->cqe.user_data = req->cqe.user_data;
1321 	notif->cqe.res = 0;
1322 	notif->cqe.flags = IORING_CQE_F_NOTIF;
1323 	req->flags |= REQ_F_NEED_CLEANUP;
1324 
1325 	zc->flags = READ_ONCE(sqe->ioprio);
1326 	if (unlikely(zc->flags & ~IO_ZC_FLAGS_COMMON)) {
1327 		if (zc->flags & ~IO_ZC_FLAGS_VALID)
1328 			return -EINVAL;
1329 		if (zc->flags & IORING_SEND_ZC_REPORT_USAGE) {
1330 			struct io_notif_data *nd = io_notif_to_data(notif);
1331 
1332 			nd->zc_report = true;
1333 			nd->zc_used = false;
1334 			nd->zc_copied = false;
1335 		}
1336 	}
1337 
1338 	if (req->opcode != IORING_OP_SEND_ZC) {
1339 		if (unlikely(sqe->addr2 || sqe->file_index))
1340 			return -EINVAL;
1341 	}
1342 
1343 	zc->len = READ_ONCE(sqe->len);
1344 	zc->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL | MSG_ZEROCOPY;
1345 	req->buf_index = READ_ONCE(sqe->buf_index);
1346 	if (zc->msg_flags & MSG_DONTWAIT)
1347 		req->flags |= REQ_F_NOWAIT;
1348 
1349 	if (io_is_compat(req->ctx))
1350 		zc->msg_flags |= MSG_CMSG_COMPAT;
1351 
1352 	if (unlikely(!io_msg_alloc_async(req)))
1353 		return -ENOMEM;
1354 	if (req->opcode == IORING_OP_SEND_ZC) {
1355 		req->flags |= REQ_F_IMPORT_BUFFER;
1356 		return io_send_setup(req, sqe);
1357 	}
1358 	return io_sendmsg_zc_setup(req, sqe);
1359 }
1360 
1361 static int io_sg_from_iter_iovec(struct sk_buff *skb,
1362 				 struct iov_iter *from, size_t length)
1363 {
1364 	skb_zcopy_downgrade_managed(skb);
1365 	return zerocopy_fill_skb_from_iter(skb, from, length);
1366 }
1367 
1368 static int io_sg_from_iter(struct sk_buff *skb,
1369 			   struct iov_iter *from, size_t length)
1370 {
1371 	struct skb_shared_info *shinfo = skb_shinfo(skb);
1372 	int frag = shinfo->nr_frags;
1373 	int ret = 0;
1374 	struct bvec_iter bi;
1375 	ssize_t copied = 0;
1376 	unsigned long truesize = 0;
1377 
1378 	if (!frag)
1379 		shinfo->flags |= SKBFL_MANAGED_FRAG_REFS;
1380 	else if (unlikely(!skb_zcopy_managed(skb)))
1381 		return zerocopy_fill_skb_from_iter(skb, from, length);
1382 
1383 	bi.bi_size = min(from->count, length);
1384 	bi.bi_bvec_done = from->iov_offset;
1385 	bi.bi_idx = 0;
1386 
1387 	while (bi.bi_size && frag < MAX_SKB_FRAGS) {
1388 		struct bio_vec v = mp_bvec_iter_bvec(from->bvec, bi);
1389 
1390 		copied += v.bv_len;
1391 		truesize += PAGE_ALIGN(v.bv_len + v.bv_offset);
1392 		__skb_fill_page_desc_noacc(shinfo, frag++, v.bv_page,
1393 					   v.bv_offset, v.bv_len);
1394 		bvec_iter_advance_single(from->bvec, &bi, v.bv_len);
1395 	}
1396 	if (bi.bi_size)
1397 		ret = -EMSGSIZE;
1398 
1399 	shinfo->nr_frags = frag;
1400 	from->bvec += bi.bi_idx;
1401 	from->nr_segs -= bi.bi_idx;
1402 	from->count -= copied;
1403 	from->iov_offset = bi.bi_bvec_done;
1404 
1405 	skb->data_len += copied;
1406 	skb->len += copied;
1407 	skb->truesize += truesize;
1408 	return ret;
1409 }
1410 
1411 static int io_send_zc_import(struct io_kiocb *req, unsigned int issue_flags)
1412 {
1413 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1414 	struct io_async_msghdr *kmsg = req->async_data;
1415 	int ret;
1416 
1417 	if (sr->flags & IORING_RECVSEND_FIXED_BUF) {
1418 		sr->notif->buf_index = req->buf_index;
1419 		ret = io_import_reg_buf(sr->notif, &kmsg->msg.msg_iter,
1420 					(u64)(uintptr_t)sr->buf, sr->len,
1421 					ITER_SOURCE, issue_flags);
1422 		if (unlikely(ret))
1423 			return ret;
1424 		kmsg->msg.sg_from_iter = io_sg_from_iter;
1425 	} else {
1426 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len, &kmsg->msg.msg_iter);
1427 		if (unlikely(ret))
1428 			return ret;
1429 		ret = io_notif_account_mem(sr->notif, sr->len);
1430 		if (unlikely(ret))
1431 			return ret;
1432 		kmsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1433 	}
1434 
1435 	return ret;
1436 }
1437 
1438 int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
1439 {
1440 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1441 	struct io_async_msghdr *kmsg = req->async_data;
1442 	struct socket *sock;
1443 	unsigned msg_flags;
1444 	int ret, min_ret = 0;
1445 
1446 	sock = sock_from_file(req->file);
1447 	if (unlikely(!sock))
1448 		return -ENOTSOCK;
1449 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1450 		return -EOPNOTSUPP;
1451 
1452 	if (!(req->flags & REQ_F_POLLED) &&
1453 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1454 		return -EAGAIN;
1455 
1456 	if (req->flags & REQ_F_IMPORT_BUFFER) {
1457 		req->flags &= ~REQ_F_IMPORT_BUFFER;
1458 		ret = io_send_zc_import(req, issue_flags);
1459 		if (unlikely(ret))
1460 			return ret;
1461 	}
1462 
1463 	msg_flags = zc->msg_flags;
1464 	if (issue_flags & IO_URING_F_NONBLOCK)
1465 		msg_flags |= MSG_DONTWAIT;
1466 	if (msg_flags & MSG_WAITALL)
1467 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1468 	msg_flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
1469 
1470 	kmsg->msg.msg_flags = msg_flags;
1471 	kmsg->msg.msg_ubuf = &io_notif_to_data(zc->notif)->uarg;
1472 	ret = sock_sendmsg(sock, &kmsg->msg);
1473 
1474 	if (unlikely(ret < min_ret)) {
1475 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1476 			return -EAGAIN;
1477 
1478 		if (ret > 0 && io_net_retry(sock, kmsg->msg.msg_flags)) {
1479 			zc->len -= ret;
1480 			zc->buf += ret;
1481 			zc->done_io += ret;
1482 			req->flags |= REQ_F_BL_NO_RECYCLE;
1483 			return -EAGAIN;
1484 		}
1485 		if (ret == -ERESTARTSYS)
1486 			ret = -EINTR;
1487 		req_set_fail(req);
1488 	}
1489 
1490 	if (ret >= 0)
1491 		ret += zc->done_io;
1492 	else if (zc->done_io)
1493 		ret = zc->done_io;
1494 
1495 	/*
1496 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1497 	 * flushing notif to io_send_zc_cleanup()
1498 	 */
1499 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1500 		io_notif_flush(zc->notif);
1501 		zc->notif = NULL;
1502 		io_req_msg_cleanup(req, 0);
1503 	}
1504 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1505 	return IOU_OK;
1506 }
1507 
1508 int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags)
1509 {
1510 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1511 	struct io_async_msghdr *kmsg = req->async_data;
1512 	struct socket *sock;
1513 	unsigned flags;
1514 	int ret, min_ret = 0;
1515 
1516 	kmsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1517 
1518 	if (req->flags & REQ_F_IMPORT_BUFFER) {
1519 		unsigned uvec_segs = kmsg->msg.msg_iter.nr_segs;
1520 		int ret;
1521 
1522 		ret = io_import_reg_vec(ITER_SOURCE, &kmsg->msg.msg_iter, req,
1523 					&kmsg->vec, uvec_segs, issue_flags);
1524 		if (unlikely(ret))
1525 			return ret;
1526 		kmsg->msg.sg_from_iter = io_sg_from_iter;
1527 		req->flags &= ~REQ_F_IMPORT_BUFFER;
1528 	}
1529 
1530 	sock = sock_from_file(req->file);
1531 	if (unlikely(!sock))
1532 		return -ENOTSOCK;
1533 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1534 		return -EOPNOTSUPP;
1535 
1536 	if (!(req->flags & REQ_F_POLLED) &&
1537 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1538 		return -EAGAIN;
1539 
1540 	flags = sr->msg_flags;
1541 	if (issue_flags & IO_URING_F_NONBLOCK)
1542 		flags |= MSG_DONTWAIT;
1543 	if (flags & MSG_WAITALL)
1544 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1545 
1546 	kmsg->msg.msg_control_user = sr->msg_control;
1547 	kmsg->msg.msg_ubuf = &io_notif_to_data(sr->notif)->uarg;
1548 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
1549 
1550 	if (unlikely(ret < min_ret)) {
1551 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1552 			return -EAGAIN;
1553 
1554 		if (ret > 0 && io_net_retry(sock, flags)) {
1555 			sr->done_io += ret;
1556 			req->flags |= REQ_F_BL_NO_RECYCLE;
1557 			return -EAGAIN;
1558 		}
1559 		if (ret == -ERESTARTSYS)
1560 			ret = -EINTR;
1561 		req_set_fail(req);
1562 	}
1563 
1564 	if (ret >= 0)
1565 		ret += sr->done_io;
1566 	else if (sr->done_io)
1567 		ret = sr->done_io;
1568 
1569 	/*
1570 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1571 	 * flushing notif to io_send_zc_cleanup()
1572 	 */
1573 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1574 		io_notif_flush(sr->notif);
1575 		sr->notif = NULL;
1576 		io_req_msg_cleanup(req, 0);
1577 	}
1578 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1579 	return IOU_OK;
1580 }
1581 
1582 void io_sendrecv_fail(struct io_kiocb *req)
1583 {
1584 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1585 
1586 	if (sr->done_io)
1587 		req->cqe.res = sr->done_io;
1588 
1589 	if ((req->flags & REQ_F_NEED_CLEANUP) &&
1590 	    (req->opcode == IORING_OP_SEND_ZC || req->opcode == IORING_OP_SENDMSG_ZC))
1591 		req->cqe.flags |= IORING_CQE_F_MORE;
1592 }
1593 
1594 #define ACCEPT_FLAGS	(IORING_ACCEPT_MULTISHOT | IORING_ACCEPT_DONTWAIT | \
1595 			 IORING_ACCEPT_POLL_FIRST)
1596 
1597 int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1598 {
1599 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1600 
1601 	if (sqe->len || sqe->buf_index)
1602 		return -EINVAL;
1603 
1604 	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1605 	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
1606 	accept->flags = READ_ONCE(sqe->accept_flags);
1607 	accept->nofile = rlimit(RLIMIT_NOFILE);
1608 	accept->iou_flags = READ_ONCE(sqe->ioprio);
1609 	if (accept->iou_flags & ~ACCEPT_FLAGS)
1610 		return -EINVAL;
1611 
1612 	accept->file_slot = READ_ONCE(sqe->file_index);
1613 	if (accept->file_slot) {
1614 		if (accept->flags & SOCK_CLOEXEC)
1615 			return -EINVAL;
1616 		if (accept->iou_flags & IORING_ACCEPT_MULTISHOT &&
1617 		    accept->file_slot != IORING_FILE_INDEX_ALLOC)
1618 			return -EINVAL;
1619 	}
1620 	if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1621 		return -EINVAL;
1622 	if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
1623 		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1624 	if (accept->iou_flags & IORING_ACCEPT_MULTISHOT)
1625 		req->flags |= REQ_F_APOLL_MULTISHOT;
1626 	if (accept->iou_flags & IORING_ACCEPT_DONTWAIT)
1627 		req->flags |= REQ_F_NOWAIT;
1628 	return 0;
1629 }
1630 
1631 int io_accept(struct io_kiocb *req, unsigned int issue_flags)
1632 {
1633 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1634 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1635 	bool fixed = !!accept->file_slot;
1636 	struct proto_accept_arg arg = {
1637 		.flags = force_nonblock ? O_NONBLOCK : 0,
1638 	};
1639 	struct file *file;
1640 	unsigned cflags;
1641 	int ret, fd;
1642 
1643 	if (!(req->flags & REQ_F_POLLED) &&
1644 	    accept->iou_flags & IORING_ACCEPT_POLL_FIRST)
1645 		return -EAGAIN;
1646 
1647 retry:
1648 	if (!fixed) {
1649 		fd = __get_unused_fd_flags(accept->flags, accept->nofile);
1650 		if (unlikely(fd < 0))
1651 			return fd;
1652 	}
1653 	arg.err = 0;
1654 	arg.is_empty = -1;
1655 	file = do_accept(req->file, &arg, accept->addr, accept->addr_len,
1656 			 accept->flags);
1657 	if (IS_ERR(file)) {
1658 		if (!fixed)
1659 			put_unused_fd(fd);
1660 		ret = PTR_ERR(file);
1661 		if (ret == -EAGAIN && force_nonblock &&
1662 		    !(accept->iou_flags & IORING_ACCEPT_DONTWAIT))
1663 			return IOU_RETRY;
1664 
1665 		if (ret == -ERESTARTSYS)
1666 			ret = -EINTR;
1667 	} else if (!fixed) {
1668 		fd_install(fd, file);
1669 		ret = fd;
1670 	} else {
1671 		ret = io_fixed_fd_install(req, issue_flags, file,
1672 						accept->file_slot);
1673 	}
1674 
1675 	cflags = 0;
1676 	if (!arg.is_empty)
1677 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
1678 
1679 	if (ret >= 0 && (req->flags & REQ_F_APOLL_MULTISHOT) &&
1680 	    io_req_post_cqe(req, ret, cflags | IORING_CQE_F_MORE)) {
1681 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || arg.is_empty == -1)
1682 			goto retry;
1683 		return IOU_RETRY;
1684 	}
1685 
1686 	io_req_set_res(req, ret, cflags);
1687 	if (ret < 0)
1688 		req_set_fail(req);
1689 	return IOU_COMPLETE;
1690 }
1691 
1692 int io_socket_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1693 {
1694 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1695 
1696 	if (sqe->addr || sqe->rw_flags || sqe->buf_index)
1697 		return -EINVAL;
1698 
1699 	sock->domain = READ_ONCE(sqe->fd);
1700 	sock->type = READ_ONCE(sqe->off);
1701 	sock->protocol = READ_ONCE(sqe->len);
1702 	sock->file_slot = READ_ONCE(sqe->file_index);
1703 	sock->nofile = rlimit(RLIMIT_NOFILE);
1704 
1705 	sock->flags = sock->type & ~SOCK_TYPE_MASK;
1706 	if (sock->file_slot && (sock->flags & SOCK_CLOEXEC))
1707 		return -EINVAL;
1708 	if (sock->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1709 		return -EINVAL;
1710 	return 0;
1711 }
1712 
1713 int io_socket(struct io_kiocb *req, unsigned int issue_flags)
1714 {
1715 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1716 	bool fixed = !!sock->file_slot;
1717 	struct file *file;
1718 	int ret, fd;
1719 
1720 	if (!fixed) {
1721 		fd = __get_unused_fd_flags(sock->flags, sock->nofile);
1722 		if (unlikely(fd < 0))
1723 			return fd;
1724 	}
1725 	file = __sys_socket_file(sock->domain, sock->type, sock->protocol);
1726 	if (IS_ERR(file)) {
1727 		if (!fixed)
1728 			put_unused_fd(fd);
1729 		ret = PTR_ERR(file);
1730 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1731 			return -EAGAIN;
1732 		if (ret == -ERESTARTSYS)
1733 			ret = -EINTR;
1734 		req_set_fail(req);
1735 	} else if (!fixed) {
1736 		fd_install(fd, file);
1737 		ret = fd;
1738 	} else {
1739 		ret = io_fixed_fd_install(req, issue_flags, file,
1740 					    sock->file_slot);
1741 	}
1742 	io_req_set_res(req, ret, 0);
1743 	return IOU_OK;
1744 }
1745 
1746 int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1747 {
1748 	struct io_connect *conn = io_kiocb_to_cmd(req, struct io_connect);
1749 	struct io_async_msghdr *io;
1750 
1751 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1752 		return -EINVAL;
1753 
1754 	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1755 	conn->addr_len =  READ_ONCE(sqe->addr2);
1756 	conn->in_progress = conn->seen_econnaborted = false;
1757 
1758 	io = io_msg_alloc_async(req);
1759 	if (unlikely(!io))
1760 		return -ENOMEM;
1761 
1762 	return move_addr_to_kernel(conn->addr, conn->addr_len, &io->addr);
1763 }
1764 
1765 int io_connect(struct io_kiocb *req, unsigned int issue_flags)
1766 {
1767 	struct io_connect *connect = io_kiocb_to_cmd(req, struct io_connect);
1768 	struct io_async_msghdr *io = req->async_data;
1769 	unsigned file_flags;
1770 	int ret;
1771 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1772 
1773 	if (unlikely(req->flags & REQ_F_FAIL)) {
1774 		ret = -ECONNRESET;
1775 		goto out;
1776 	}
1777 
1778 	file_flags = force_nonblock ? O_NONBLOCK : 0;
1779 
1780 	ret = __sys_connect_file(req->file, &io->addr, connect->addr_len,
1781 				 file_flags);
1782 	if ((ret == -EAGAIN || ret == -EINPROGRESS || ret == -ECONNABORTED)
1783 	    && force_nonblock) {
1784 		if (ret == -EINPROGRESS) {
1785 			connect->in_progress = true;
1786 		} else if (ret == -ECONNABORTED) {
1787 			if (connect->seen_econnaborted)
1788 				goto out;
1789 			connect->seen_econnaborted = true;
1790 		}
1791 		return -EAGAIN;
1792 	}
1793 	if (connect->in_progress) {
1794 		/*
1795 		 * At least bluetooth will return -EBADFD on a re-connect
1796 		 * attempt, and it's (supposedly) also valid to get -EISCONN
1797 		 * which means the previous result is good. For both of these,
1798 		 * grab the sock_error() and use that for the completion.
1799 		 */
1800 		if (ret == -EBADFD || ret == -EISCONN)
1801 			ret = sock_error(sock_from_file(req->file)->sk);
1802 	}
1803 	if (ret == -ERESTARTSYS)
1804 		ret = -EINTR;
1805 out:
1806 	if (ret < 0)
1807 		req_set_fail(req);
1808 	io_req_msg_cleanup(req, issue_flags);
1809 	io_req_set_res(req, ret, 0);
1810 	return IOU_OK;
1811 }
1812 
1813 int io_bind_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1814 {
1815 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1816 	struct sockaddr __user *uaddr;
1817 	struct io_async_msghdr *io;
1818 
1819 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1820 		return -EINVAL;
1821 
1822 	uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1823 	bind->addr_len =  READ_ONCE(sqe->addr2);
1824 
1825 	io = io_msg_alloc_async(req);
1826 	if (unlikely(!io))
1827 		return -ENOMEM;
1828 	return move_addr_to_kernel(uaddr, bind->addr_len, &io->addr);
1829 }
1830 
1831 int io_bind(struct io_kiocb *req, unsigned int issue_flags)
1832 {
1833 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1834 	struct io_async_msghdr *io = req->async_data;
1835 	struct socket *sock;
1836 	int ret;
1837 
1838 	sock = sock_from_file(req->file);
1839 	if (unlikely(!sock))
1840 		return -ENOTSOCK;
1841 
1842 	ret = __sys_bind_socket(sock, &io->addr, bind->addr_len);
1843 	if (ret < 0)
1844 		req_set_fail(req);
1845 	io_req_set_res(req, ret, 0);
1846 	return 0;
1847 }
1848 
1849 int io_listen_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1850 {
1851 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1852 
1853 	if (sqe->addr || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in || sqe->addr2)
1854 		return -EINVAL;
1855 
1856 	listen->backlog = READ_ONCE(sqe->len);
1857 	return 0;
1858 }
1859 
1860 int io_listen(struct io_kiocb *req, unsigned int issue_flags)
1861 {
1862 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1863 	struct socket *sock;
1864 	int ret;
1865 
1866 	sock = sock_from_file(req->file);
1867 	if (unlikely(!sock))
1868 		return -ENOTSOCK;
1869 
1870 	ret = __sys_listen_socket(sock, listen->backlog);
1871 	if (ret < 0)
1872 		req_set_fail(req);
1873 	io_req_set_res(req, ret, 0);
1874 	return 0;
1875 }
1876 
1877 void io_netmsg_cache_free(const void *entry)
1878 {
1879 	struct io_async_msghdr *kmsg = (struct io_async_msghdr *) entry;
1880 
1881 	io_vec_free(&kmsg->vec);
1882 	kfree(kmsg);
1883 }
1884 #endif
1885