xref: /linux/io_uring/net.c (revision d07de43e3f05576fd275c8c82e413d91932119a5)
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 
20 #if defined(CONFIG_NET)
21 struct io_shutdown {
22 	struct file			*file;
23 	int				how;
24 };
25 
26 struct io_accept {
27 	struct file			*file;
28 	struct sockaddr __user		*addr;
29 	int __user			*addr_len;
30 	int				flags;
31 	int				iou_flags;
32 	u32				file_slot;
33 	unsigned long			nofile;
34 };
35 
36 struct io_socket {
37 	struct file			*file;
38 	int				domain;
39 	int				type;
40 	int				protocol;
41 	int				flags;
42 	u32				file_slot;
43 	unsigned long			nofile;
44 };
45 
46 struct io_connect {
47 	struct file			*file;
48 	struct sockaddr __user		*addr;
49 	int				addr_len;
50 	bool				in_progress;
51 	bool				seen_econnaborted;
52 };
53 
54 struct io_bind {
55 	struct file			*file;
56 	int				addr_len;
57 };
58 
59 struct io_listen {
60 	struct file			*file;
61 	int				backlog;
62 };
63 
64 struct io_sr_msg {
65 	struct file			*file;
66 	union {
67 		struct compat_msghdr __user	*umsg_compat;
68 		struct user_msghdr __user	*umsg;
69 		void __user			*buf;
70 	};
71 	int				len;
72 	unsigned			done_io;
73 	unsigned			msg_flags;
74 	unsigned			nr_multishot_loops;
75 	u16				flags;
76 	/* initialised and used only by !msg send variants */
77 	u16				buf_group;
78 	u16				buf_index;
79 	void __user			*msg_control;
80 	/* used only for send zerocopy */
81 	struct io_kiocb 		*notif;
82 };
83 
84 /*
85  * Number of times we'll try and do receives if there's more data. If we
86  * exceed this limit, then add us to the back of the queue and retry from
87  * there. This helps fairness between flooding clients.
88  */
89 #define MULTISHOT_MAX_RETRY	32
90 
io_shutdown_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)91 int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
92 {
93 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
94 
95 	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
96 		     sqe->buf_index || sqe->splice_fd_in))
97 		return -EINVAL;
98 
99 	shutdown->how = READ_ONCE(sqe->len);
100 	req->flags |= REQ_F_FORCE_ASYNC;
101 	return 0;
102 }
103 
io_shutdown(struct io_kiocb * req,unsigned int issue_flags)104 int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
105 {
106 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
107 	struct socket *sock;
108 	int ret;
109 
110 	WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
111 
112 	sock = sock_from_file(req->file);
113 	if (unlikely(!sock))
114 		return -ENOTSOCK;
115 
116 	ret = __sys_shutdown_sock(sock, shutdown->how);
117 	io_req_set_res(req, ret, 0);
118 	return IOU_OK;
119 }
120 
io_net_retry(struct socket * sock,int flags)121 static bool io_net_retry(struct socket *sock, int flags)
122 {
123 	if (!(flags & MSG_WAITALL))
124 		return false;
125 	return sock->type == SOCK_STREAM || sock->type == SOCK_SEQPACKET;
126 }
127 
io_netmsg_iovec_free(struct io_async_msghdr * kmsg)128 static void io_netmsg_iovec_free(struct io_async_msghdr *kmsg)
129 {
130 	if (kmsg->free_iov) {
131 		kfree(kmsg->free_iov);
132 		kmsg->free_iov_nr = 0;
133 		kmsg->free_iov = NULL;
134 	}
135 }
136 
io_netmsg_recycle(struct io_kiocb * req,unsigned int issue_flags)137 static void io_netmsg_recycle(struct io_kiocb *req, unsigned int issue_flags)
138 {
139 	struct io_async_msghdr *hdr = req->async_data;
140 
141 	/* can't recycle, ensure we free the iovec if we have one */
142 	if (unlikely(issue_flags & IO_URING_F_UNLOCKED)) {
143 		io_netmsg_iovec_free(hdr);
144 		return;
145 	}
146 
147 	/* Let normal cleanup path reap it if we fail adding to the cache */
148 	io_alloc_cache_kasan(&hdr->free_iov, &hdr->free_iov_nr);
149 	if (io_alloc_cache_put(&req->ctx->netmsg_cache, hdr)) {
150 		req->async_data = NULL;
151 		req->flags &= ~(REQ_F_ASYNC_DATA|REQ_F_NEED_CLEANUP);
152 	}
153 }
154 
io_msg_alloc_async(struct io_kiocb * req)155 static struct io_async_msghdr *io_msg_alloc_async(struct io_kiocb *req)
156 {
157 	struct io_ring_ctx *ctx = req->ctx;
158 	struct io_async_msghdr *hdr;
159 
160 	hdr = io_uring_alloc_async_data(&ctx->netmsg_cache, req);
161 	if (!hdr)
162 		return NULL;
163 
164 	/* If the async data was cached, we might have an iov cached inside. */
165 	if (hdr->free_iov)
166 		req->flags |= REQ_F_NEED_CLEANUP;
167 	return hdr;
168 }
169 
170 /* assign new iovec to kmsg, if we need to */
io_net_vec_assign(struct io_kiocb * req,struct io_async_msghdr * kmsg,struct iovec * iov)171 static void io_net_vec_assign(struct io_kiocb *req, struct io_async_msghdr *kmsg,
172 			     struct iovec *iov)
173 {
174 	if (iov) {
175 		req->flags |= REQ_F_NEED_CLEANUP;
176 		kmsg->free_iov_nr = kmsg->msg.msg_iter.nr_segs;
177 		if (kmsg->free_iov)
178 			kfree(kmsg->free_iov);
179 		kmsg->free_iov = iov;
180 	}
181 }
182 
io_mshot_prep_retry(struct io_kiocb * req,struct io_async_msghdr * kmsg)183 static inline void io_mshot_prep_retry(struct io_kiocb *req,
184 				       struct io_async_msghdr *kmsg)
185 {
186 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
187 
188 	req->flags &= ~REQ_F_BL_EMPTY;
189 	sr->done_io = 0;
190 	sr->len = 0; /* get from the provided buffer */
191 	req->buf_index = sr->buf_group;
192 }
193 
194 #ifdef CONFIG_COMPAT
io_compat_msg_copy_hdr(struct io_kiocb * req,struct io_async_msghdr * iomsg,struct compat_msghdr * msg,int ddir)195 static int io_compat_msg_copy_hdr(struct io_kiocb *req,
196 				  struct io_async_msghdr *iomsg,
197 				  struct compat_msghdr *msg, int ddir)
198 {
199 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
200 	struct compat_iovec __user *uiov;
201 	struct iovec *iov;
202 	int ret, nr_segs;
203 
204 	if (iomsg->free_iov) {
205 		nr_segs = iomsg->free_iov_nr;
206 		iov = iomsg->free_iov;
207 	} else {
208 		iov = &iomsg->fast_iov;
209 		nr_segs = 1;
210 	}
211 
212 	if (copy_from_user(msg, sr->umsg_compat, sizeof(*msg)))
213 		return -EFAULT;
214 
215 	uiov = compat_ptr(msg->msg_iov);
216 	if (req->flags & REQ_F_BUFFER_SELECT) {
217 		compat_ssize_t clen;
218 
219 		if (msg->msg_iovlen == 0) {
220 			sr->len = iov->iov_len = 0;
221 			iov->iov_base = NULL;
222 		} else if (msg->msg_iovlen > 1) {
223 			return -EINVAL;
224 		} else {
225 			if (!access_ok(uiov, sizeof(*uiov)))
226 				return -EFAULT;
227 			if (__get_user(clen, &uiov->iov_len))
228 				return -EFAULT;
229 			if (clen < 0)
230 				return -EINVAL;
231 			sr->len = clen;
232 		}
233 
234 		return 0;
235 	}
236 
237 	ret = __import_iovec(ddir, (struct iovec __user *)uiov, msg->msg_iovlen,
238 				nr_segs, &iov, &iomsg->msg.msg_iter, true);
239 	if (unlikely(ret < 0))
240 		return ret;
241 
242 	io_net_vec_assign(req, iomsg, iov);
243 	return 0;
244 }
245 #endif
246 
io_msg_copy_hdr(struct io_kiocb * req,struct io_async_msghdr * iomsg,struct user_msghdr * msg,int ddir)247 static int io_msg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg,
248 			   struct user_msghdr *msg, int ddir)
249 {
250 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
251 	struct user_msghdr __user *umsg = sr->umsg;
252 	struct iovec *iov;
253 	int ret, nr_segs;
254 
255 	if (iomsg->free_iov) {
256 		nr_segs = iomsg->free_iov_nr;
257 		iov = iomsg->free_iov;
258 	} else {
259 		iov = &iomsg->fast_iov;
260 		nr_segs = 1;
261 	}
262 
263 	if (!user_access_begin(umsg, sizeof(*umsg)))
264 		return -EFAULT;
265 
266 	ret = -EFAULT;
267 	unsafe_get_user(msg->msg_name, &umsg->msg_name, ua_end);
268 	unsafe_get_user(msg->msg_namelen, &umsg->msg_namelen, ua_end);
269 	unsafe_get_user(msg->msg_iov, &umsg->msg_iov, ua_end);
270 	unsafe_get_user(msg->msg_iovlen, &umsg->msg_iovlen, ua_end);
271 	unsafe_get_user(msg->msg_control, &umsg->msg_control, ua_end);
272 	unsafe_get_user(msg->msg_controllen, &umsg->msg_controllen, ua_end);
273 	msg->msg_flags = 0;
274 
275 	if (req->flags & REQ_F_BUFFER_SELECT) {
276 		if (msg->msg_iovlen == 0) {
277 			sr->len = iov->iov_len = 0;
278 			iov->iov_base = NULL;
279 		} else if (msg->msg_iovlen > 1) {
280 			ret = -EINVAL;
281 			goto ua_end;
282 		} else {
283 			struct iovec __user *uiov = msg->msg_iov;
284 
285 			/* we only need the length for provided buffers */
286 			if (!access_ok(&uiov->iov_len, sizeof(uiov->iov_len)))
287 				goto ua_end;
288 			unsafe_get_user(iov->iov_len, &uiov->iov_len, ua_end);
289 			sr->len = iov->iov_len;
290 		}
291 		ret = 0;
292 ua_end:
293 		user_access_end();
294 		return ret;
295 	}
296 
297 	user_access_end();
298 	ret = __import_iovec(ddir, msg->msg_iov, msg->msg_iovlen, nr_segs,
299 				&iov, &iomsg->msg.msg_iter, false);
300 	if (unlikely(ret < 0))
301 		return ret;
302 
303 	io_net_vec_assign(req, iomsg, iov);
304 	return 0;
305 }
306 
io_sendmsg_copy_hdr(struct io_kiocb * req,struct io_async_msghdr * iomsg)307 static int io_sendmsg_copy_hdr(struct io_kiocb *req,
308 			       struct io_async_msghdr *iomsg)
309 {
310 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
311 	struct user_msghdr msg;
312 	int ret;
313 
314 	iomsg->msg.msg_name = &iomsg->addr;
315 	iomsg->msg.msg_iter.nr_segs = 0;
316 
317 #ifdef CONFIG_COMPAT
318 	if (unlikely(req->ctx->compat)) {
319 		struct compat_msghdr cmsg;
320 
321 		ret = io_compat_msg_copy_hdr(req, iomsg, &cmsg, ITER_SOURCE);
322 		if (unlikely(ret))
323 			return ret;
324 
325 		ret = __get_compat_msghdr(&iomsg->msg, &cmsg, NULL);
326 		sr->msg_control = iomsg->msg.msg_control_user;
327 		return ret;
328 	}
329 #endif
330 
331 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_SOURCE);
332 	if (unlikely(ret))
333 		return ret;
334 
335 	ret = __copy_msghdr(&iomsg->msg, &msg, NULL);
336 
337 	/* save msg_control as sys_sendmsg() overwrites it */
338 	sr->msg_control = iomsg->msg.msg_control_user;
339 	return ret;
340 }
341 
io_sendmsg_recvmsg_cleanup(struct io_kiocb * req)342 void io_sendmsg_recvmsg_cleanup(struct io_kiocb *req)
343 {
344 	struct io_async_msghdr *io = req->async_data;
345 
346 	io_netmsg_iovec_free(io);
347 }
348 
io_send_setup(struct io_kiocb * req,const struct io_uring_sqe * sqe)349 static int io_send_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
350 {
351 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
352 	struct io_async_msghdr *kmsg = req->async_data;
353 	void __user *addr;
354 	u16 addr_len;
355 	int ret;
356 
357 	sr->buf = u64_to_user_ptr(READ_ONCE(sqe->addr));
358 
359 	if (READ_ONCE(sqe->__pad3[0]))
360 		return -EINVAL;
361 
362 	kmsg->msg.msg_name = NULL;
363 	kmsg->msg.msg_namelen = 0;
364 	kmsg->msg.msg_control = NULL;
365 	kmsg->msg.msg_controllen = 0;
366 	kmsg->msg.msg_ubuf = NULL;
367 
368 	addr = u64_to_user_ptr(READ_ONCE(sqe->addr2));
369 	addr_len = READ_ONCE(sqe->addr_len);
370 	if (addr) {
371 		ret = move_addr_to_kernel(addr, addr_len, &kmsg->addr);
372 		if (unlikely(ret < 0))
373 			return ret;
374 		kmsg->msg.msg_name = &kmsg->addr;
375 		kmsg->msg.msg_namelen = addr_len;
376 	}
377 	if (!io_do_buffer_select(req)) {
378 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
379 				  &kmsg->msg.msg_iter);
380 		if (unlikely(ret < 0))
381 			return ret;
382 	}
383 	return 0;
384 }
385 
io_sendmsg_setup(struct io_kiocb * req,const struct io_uring_sqe * sqe)386 static int io_sendmsg_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
387 {
388 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
389 	struct io_async_msghdr *kmsg = req->async_data;
390 	int ret;
391 
392 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
393 
394 	ret = io_sendmsg_copy_hdr(req, kmsg);
395 	if (!ret)
396 		req->flags |= REQ_F_NEED_CLEANUP;
397 	return ret;
398 }
399 
400 #define SENDMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_BUNDLE)
401 
io_sendmsg_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)402 int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
403 {
404 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
405 
406 	sr->done_io = 0;
407 
408 	if (req->opcode != IORING_OP_SEND) {
409 		if (sqe->addr2 || sqe->file_index)
410 			return -EINVAL;
411 	}
412 
413 	sr->len = READ_ONCE(sqe->len);
414 	sr->flags = READ_ONCE(sqe->ioprio);
415 	if (sr->flags & ~SENDMSG_FLAGS)
416 		return -EINVAL;
417 	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
418 	if (sr->msg_flags & MSG_DONTWAIT)
419 		req->flags |= REQ_F_NOWAIT;
420 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
421 		if (req->opcode == IORING_OP_SENDMSG)
422 			return -EINVAL;
423 		if (!(req->flags & REQ_F_BUFFER_SELECT))
424 			return -EINVAL;
425 		sr->msg_flags |= MSG_WAITALL;
426 		sr->buf_group = req->buf_index;
427 		req->buf_list = NULL;
428 	}
429 
430 #ifdef CONFIG_COMPAT
431 	if (req->ctx->compat)
432 		sr->msg_flags |= MSG_CMSG_COMPAT;
433 #endif
434 	if (unlikely(!io_msg_alloc_async(req)))
435 		return -ENOMEM;
436 	if (req->opcode != IORING_OP_SENDMSG)
437 		return io_send_setup(req, sqe);
438 	return io_sendmsg_setup(req, sqe);
439 }
440 
io_req_msg_cleanup(struct io_kiocb * req,unsigned int issue_flags)441 static void io_req_msg_cleanup(struct io_kiocb *req,
442 			       unsigned int issue_flags)
443 {
444 	io_netmsg_recycle(req, issue_flags);
445 }
446 
447 /*
448  * For bundle completions, we need to figure out how many segments we consumed.
449  * A bundle could be using a single ITER_UBUF if that's all we mapped, or it
450  * could be using an ITER_IOVEC. If the latter, then if we consumed all of
451  * the segments, then it's a trivial questiont o answer. If we have residual
452  * data in the iter, then loop the segments to figure out how much we
453  * transferred.
454  */
io_bundle_nbufs(struct io_async_msghdr * kmsg,int ret)455 static int io_bundle_nbufs(struct io_async_msghdr *kmsg, int ret)
456 {
457 	struct iovec *iov;
458 	int nbufs;
459 
460 	/* no data is always zero segments, and a ubuf is always 1 segment */
461 	if (ret <= 0)
462 		return 0;
463 	if (iter_is_ubuf(&kmsg->msg.msg_iter))
464 		return 1;
465 
466 	iov = kmsg->free_iov;
467 	if (!iov)
468 		iov = &kmsg->fast_iov;
469 
470 	/* if all data was transferred, it's basic pointer math */
471 	if (!iov_iter_count(&kmsg->msg.msg_iter))
472 		return iter_iov(&kmsg->msg.msg_iter) - iov;
473 
474 	/* short transfer, count segments */
475 	nbufs = 0;
476 	do {
477 		int this_len = min_t(int, iov[nbufs].iov_len, ret);
478 
479 		nbufs++;
480 		ret -= this_len;
481 	} while (ret);
482 
483 	return nbufs;
484 }
485 
io_send_finish(struct io_kiocb * req,int * ret,struct io_async_msghdr * kmsg,unsigned issue_flags)486 static inline bool io_send_finish(struct io_kiocb *req, int *ret,
487 				  struct io_async_msghdr *kmsg,
488 				  unsigned issue_flags)
489 {
490 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
491 	bool bundle_finished = *ret <= 0;
492 	unsigned int cflags;
493 
494 	if (!(sr->flags & IORING_RECVSEND_BUNDLE)) {
495 		cflags = io_put_kbuf(req, *ret, issue_flags);
496 		goto finish;
497 	}
498 
499 	cflags = io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret), issue_flags);
500 
501 	if (bundle_finished || req->flags & REQ_F_BL_EMPTY)
502 		goto finish;
503 
504 	/*
505 	 * Fill CQE for this receive and see if we should keep trying to
506 	 * receive from this socket.
507 	 */
508 	if (io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
509 		io_mshot_prep_retry(req, kmsg);
510 		return false;
511 	}
512 
513 	/* Otherwise stop bundle and use the current result. */
514 finish:
515 	io_req_set_res(req, *ret, cflags);
516 	*ret = IOU_OK;
517 	return true;
518 }
519 
io_sendmsg(struct io_kiocb * req,unsigned int issue_flags)520 int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
521 {
522 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
523 	struct io_async_msghdr *kmsg = req->async_data;
524 	struct socket *sock;
525 	unsigned flags;
526 	int min_ret = 0;
527 	int ret;
528 
529 	sock = sock_from_file(req->file);
530 	if (unlikely(!sock))
531 		return -ENOTSOCK;
532 
533 	if (!(req->flags & REQ_F_POLLED) &&
534 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
535 		return -EAGAIN;
536 
537 	flags = sr->msg_flags;
538 	if (issue_flags & IO_URING_F_NONBLOCK)
539 		flags |= MSG_DONTWAIT;
540 	if (flags & MSG_WAITALL)
541 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
542 
543 	kmsg->msg.msg_control_user = sr->msg_control;
544 
545 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
546 
547 	if (ret < min_ret) {
548 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
549 			return -EAGAIN;
550 		if (ret > 0 && io_net_retry(sock, flags)) {
551 			kmsg->msg.msg_controllen = 0;
552 			kmsg->msg.msg_control = NULL;
553 			sr->done_io += ret;
554 			req->flags |= REQ_F_BL_NO_RECYCLE;
555 			return -EAGAIN;
556 		}
557 		if (ret == -ERESTARTSYS)
558 			ret = -EINTR;
559 		req_set_fail(req);
560 	}
561 	io_req_msg_cleanup(req, issue_flags);
562 	if (ret >= 0)
563 		ret += sr->done_io;
564 	else if (sr->done_io)
565 		ret = sr->done_io;
566 	io_req_set_res(req, ret, 0);
567 	return IOU_OK;
568 }
569 
io_send_select_buffer(struct io_kiocb * req,unsigned int issue_flags,struct io_async_msghdr * kmsg)570 static int io_send_select_buffer(struct io_kiocb *req, unsigned int issue_flags,
571 				 struct io_async_msghdr *kmsg)
572 {
573 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
574 
575 	int ret;
576 	struct buf_sel_arg arg = {
577 		.iovs = &kmsg->fast_iov,
578 		.max_len = min_not_zero(sr->len, INT_MAX),
579 		.nr_iovs = 1,
580 	};
581 
582 	if (kmsg->free_iov) {
583 		arg.nr_iovs = kmsg->free_iov_nr;
584 		arg.iovs = kmsg->free_iov;
585 		arg.mode = KBUF_MODE_FREE;
586 	}
587 
588 	if (!(sr->flags & IORING_RECVSEND_BUNDLE))
589 		arg.nr_iovs = 1;
590 	else
591 		arg.mode |= KBUF_MODE_EXPAND;
592 
593 	ret = io_buffers_select(req, &arg, issue_flags);
594 	if (unlikely(ret < 0))
595 		return ret;
596 
597 	if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) {
598 		kmsg->free_iov_nr = ret;
599 		kmsg->free_iov = arg.iovs;
600 		req->flags |= REQ_F_NEED_CLEANUP;
601 	}
602 	sr->len = arg.out_len;
603 
604 	if (ret == 1) {
605 		sr->buf = arg.iovs[0].iov_base;
606 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
607 					&kmsg->msg.msg_iter);
608 		if (unlikely(ret))
609 			return ret;
610 	} else {
611 		iov_iter_init(&kmsg->msg.msg_iter, ITER_SOURCE,
612 				arg.iovs, ret, arg.out_len);
613 	}
614 
615 	return 0;
616 }
617 
io_send(struct io_kiocb * req,unsigned int issue_flags)618 int io_send(struct io_kiocb *req, unsigned int issue_flags)
619 {
620 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
621 	struct io_async_msghdr *kmsg = req->async_data;
622 	struct socket *sock;
623 	unsigned flags;
624 	int min_ret = 0;
625 	int ret;
626 
627 	sock = sock_from_file(req->file);
628 	if (unlikely(!sock))
629 		return -ENOTSOCK;
630 
631 	if (!(req->flags & REQ_F_POLLED) &&
632 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
633 		return -EAGAIN;
634 
635 	flags = sr->msg_flags;
636 	if (issue_flags & IO_URING_F_NONBLOCK)
637 		flags |= MSG_DONTWAIT;
638 
639 retry_bundle:
640 	if (io_do_buffer_select(req)) {
641 		ret = io_send_select_buffer(req, issue_flags, kmsg);
642 		if (ret)
643 			return ret;
644 	}
645 
646 	/*
647 	 * If MSG_WAITALL is set, or this is a bundle send, then we need
648 	 * the full amount. If just bundle is set, if we do a short send
649 	 * then we complete the bundle sequence rather than continue on.
650 	 */
651 	if (flags & MSG_WAITALL || sr->flags & IORING_RECVSEND_BUNDLE)
652 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
653 
654 	flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
655 	kmsg->msg.msg_flags = flags;
656 	ret = sock_sendmsg(sock, &kmsg->msg);
657 	if (ret < min_ret) {
658 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
659 			return -EAGAIN;
660 
661 		if (ret > 0 && io_net_retry(sock, flags)) {
662 			sr->len -= ret;
663 			sr->buf += ret;
664 			sr->done_io += ret;
665 			req->flags |= REQ_F_BL_NO_RECYCLE;
666 			return -EAGAIN;
667 		}
668 		if (ret == -ERESTARTSYS)
669 			ret = -EINTR;
670 		req_set_fail(req);
671 	}
672 	if (ret >= 0)
673 		ret += sr->done_io;
674 	else if (sr->done_io)
675 		ret = sr->done_io;
676 
677 	if (!io_send_finish(req, &ret, kmsg, issue_flags))
678 		goto retry_bundle;
679 
680 	io_req_msg_cleanup(req, issue_flags);
681 	return ret;
682 }
683 
io_recvmsg_mshot_prep(struct io_kiocb * req,struct io_async_msghdr * iomsg,int namelen,size_t controllen)684 static int io_recvmsg_mshot_prep(struct io_kiocb *req,
685 				 struct io_async_msghdr *iomsg,
686 				 int namelen, size_t controllen)
687 {
688 	if ((req->flags & (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) ==
689 			  (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) {
690 		int hdr;
691 
692 		if (unlikely(namelen < 0))
693 			return -EOVERFLOW;
694 		if (check_add_overflow(sizeof(struct io_uring_recvmsg_out),
695 					namelen, &hdr))
696 			return -EOVERFLOW;
697 		if (check_add_overflow(hdr, controllen, &hdr))
698 			return -EOVERFLOW;
699 
700 		iomsg->namelen = namelen;
701 		iomsg->controllen = controllen;
702 		return 0;
703 	}
704 
705 	return 0;
706 }
707 
io_recvmsg_copy_hdr(struct io_kiocb * req,struct io_async_msghdr * iomsg)708 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
709 			       struct io_async_msghdr *iomsg)
710 {
711 	struct user_msghdr msg;
712 	int ret;
713 
714 	iomsg->msg.msg_name = &iomsg->addr;
715 	iomsg->msg.msg_iter.nr_segs = 0;
716 
717 #ifdef CONFIG_COMPAT
718 	if (unlikely(req->ctx->compat)) {
719 		struct compat_msghdr cmsg;
720 
721 		ret = io_compat_msg_copy_hdr(req, iomsg, &cmsg, ITER_DEST);
722 		if (unlikely(ret))
723 			return ret;
724 
725 		ret = __get_compat_msghdr(&iomsg->msg, &cmsg, &iomsg->uaddr);
726 		if (unlikely(ret))
727 			return ret;
728 
729 		return io_recvmsg_mshot_prep(req, iomsg, cmsg.msg_namelen,
730 						cmsg.msg_controllen);
731 	}
732 #endif
733 
734 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_DEST);
735 	if (unlikely(ret))
736 		return ret;
737 
738 	ret = __copy_msghdr(&iomsg->msg, &msg, &iomsg->uaddr);
739 	if (unlikely(ret))
740 		return ret;
741 
742 	return io_recvmsg_mshot_prep(req, iomsg, msg.msg_namelen,
743 					msg.msg_controllen);
744 }
745 
io_recvmsg_prep_setup(struct io_kiocb * req)746 static int io_recvmsg_prep_setup(struct io_kiocb *req)
747 {
748 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
749 	struct io_async_msghdr *kmsg;
750 	int ret;
751 
752 	kmsg = io_msg_alloc_async(req);
753 	if (unlikely(!kmsg))
754 		return -ENOMEM;
755 
756 	if (req->opcode == IORING_OP_RECV) {
757 		kmsg->msg.msg_name = NULL;
758 		kmsg->msg.msg_namelen = 0;
759 		kmsg->msg.msg_inq = 0;
760 		kmsg->msg.msg_control = NULL;
761 		kmsg->msg.msg_get_inq = 1;
762 		kmsg->msg.msg_controllen = 0;
763 		kmsg->msg.msg_iocb = NULL;
764 		kmsg->msg.msg_ubuf = NULL;
765 
766 		if (!io_do_buffer_select(req)) {
767 			ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
768 					  &kmsg->msg.msg_iter);
769 			if (unlikely(ret))
770 				return ret;
771 		}
772 		return 0;
773 	}
774 
775 	ret = io_recvmsg_copy_hdr(req, kmsg);
776 	if (!ret)
777 		req->flags |= REQ_F_NEED_CLEANUP;
778 	return ret;
779 }
780 
781 #define RECVMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT | \
782 			IORING_RECVSEND_BUNDLE)
783 
io_recvmsg_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)784 int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
785 {
786 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
787 
788 	sr->done_io = 0;
789 
790 	if (unlikely(sqe->file_index || sqe->addr2))
791 		return -EINVAL;
792 
793 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
794 	sr->len = READ_ONCE(sqe->len);
795 	sr->flags = READ_ONCE(sqe->ioprio);
796 	if (sr->flags & ~RECVMSG_FLAGS)
797 		return -EINVAL;
798 	sr->msg_flags = READ_ONCE(sqe->msg_flags);
799 	if (sr->msg_flags & MSG_DONTWAIT)
800 		req->flags |= REQ_F_NOWAIT;
801 	if (sr->msg_flags & MSG_ERRQUEUE)
802 		req->flags |= REQ_F_CLEAR_POLLIN;
803 	if (req->flags & REQ_F_BUFFER_SELECT) {
804 		/*
805 		 * Store the buffer group for this multishot receive separately,
806 		 * as if we end up doing an io-wq based issue that selects a
807 		 * buffer, it has to be committed immediately and that will
808 		 * clear ->buf_list. This means we lose the link to the buffer
809 		 * list, and the eventual buffer put on completion then cannot
810 		 * restore it.
811 		 */
812 		sr->buf_group = req->buf_index;
813 		req->buf_list = NULL;
814 	}
815 	if (sr->flags & IORING_RECV_MULTISHOT) {
816 		if (!(req->flags & REQ_F_BUFFER_SELECT))
817 			return -EINVAL;
818 		if (sr->msg_flags & MSG_WAITALL)
819 			return -EINVAL;
820 		if (req->opcode == IORING_OP_RECV && sr->len)
821 			return -EINVAL;
822 		req->flags |= REQ_F_APOLL_MULTISHOT;
823 	}
824 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
825 		if (req->opcode == IORING_OP_RECVMSG)
826 			return -EINVAL;
827 	}
828 
829 #ifdef CONFIG_COMPAT
830 	if (req->ctx->compat)
831 		sr->msg_flags |= MSG_CMSG_COMPAT;
832 #endif
833 	sr->nr_multishot_loops = 0;
834 	return io_recvmsg_prep_setup(req);
835 }
836 
837 /*
838  * Finishes io_recv and io_recvmsg.
839  *
840  * Returns true if it is actually finished, or false if it should run
841  * again (for multishot).
842  */
io_recv_finish(struct io_kiocb * req,int * ret,struct io_async_msghdr * kmsg,bool mshot_finished,unsigned issue_flags)843 static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
844 				  struct io_async_msghdr *kmsg,
845 				  bool mshot_finished, unsigned issue_flags)
846 {
847 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
848 	unsigned int cflags = 0;
849 
850 	if (kmsg->msg.msg_inq > 0)
851 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
852 
853 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
854 		cflags |= io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret),
855 				      issue_flags);
856 		/* bundle with no more immediate buffers, we're done */
857 		if (req->flags & REQ_F_BL_EMPTY)
858 			goto finish;
859 	} else {
860 		cflags |= io_put_kbuf(req, *ret, issue_flags);
861 	}
862 
863 	/*
864 	 * Fill CQE for this receive and see if we should keep trying to
865 	 * receive from this socket.
866 	 */
867 	if ((req->flags & REQ_F_APOLL_MULTISHOT) && !mshot_finished &&
868 	    io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
869 		int mshot_retry_ret = IOU_ISSUE_SKIP_COMPLETE;
870 
871 		io_mshot_prep_retry(req, kmsg);
872 		/* Known not-empty or unknown state, retry */
873 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || kmsg->msg.msg_inq < 0) {
874 			if (sr->nr_multishot_loops++ < MULTISHOT_MAX_RETRY)
875 				return false;
876 			/* mshot retries exceeded, force a requeue */
877 			sr->nr_multishot_loops = 0;
878 			mshot_retry_ret = IOU_REQUEUE;
879 		}
880 		if (issue_flags & IO_URING_F_MULTISHOT)
881 			*ret = mshot_retry_ret;
882 		else
883 			*ret = -EAGAIN;
884 		return true;
885 	}
886 
887 	/* Finish the request / stop multishot. */
888 finish:
889 	io_req_set_res(req, *ret, cflags);
890 
891 	if (issue_flags & IO_URING_F_MULTISHOT)
892 		*ret = IOU_STOP_MULTISHOT;
893 	else
894 		*ret = IOU_OK;
895 	io_req_msg_cleanup(req, issue_flags);
896 	return true;
897 }
898 
io_recvmsg_prep_multishot(struct io_async_msghdr * kmsg,struct io_sr_msg * sr,void __user ** buf,size_t * len)899 static int io_recvmsg_prep_multishot(struct io_async_msghdr *kmsg,
900 				     struct io_sr_msg *sr, void __user **buf,
901 				     size_t *len)
902 {
903 	unsigned long ubuf = (unsigned long) *buf;
904 	unsigned long hdr;
905 
906 	hdr = sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
907 		kmsg->controllen;
908 	if (*len < hdr)
909 		return -EFAULT;
910 
911 	if (kmsg->controllen) {
912 		unsigned long control = ubuf + hdr - kmsg->controllen;
913 
914 		kmsg->msg.msg_control_user = (void __user *) control;
915 		kmsg->msg.msg_controllen = kmsg->controllen;
916 	}
917 
918 	sr->buf = *buf; /* stash for later copy */
919 	*buf = (void __user *) (ubuf + hdr);
920 	kmsg->payloadlen = *len = *len - hdr;
921 	return 0;
922 }
923 
924 struct io_recvmsg_multishot_hdr {
925 	struct io_uring_recvmsg_out msg;
926 	struct sockaddr_storage addr;
927 };
928 
io_recvmsg_multishot(struct socket * sock,struct io_sr_msg * io,struct io_async_msghdr * kmsg,unsigned int flags,bool * finished)929 static int io_recvmsg_multishot(struct socket *sock, struct io_sr_msg *io,
930 				struct io_async_msghdr *kmsg,
931 				unsigned int flags, bool *finished)
932 {
933 	int err;
934 	int copy_len;
935 	struct io_recvmsg_multishot_hdr hdr;
936 
937 	if (kmsg->namelen)
938 		kmsg->msg.msg_name = &hdr.addr;
939 	kmsg->msg.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
940 	kmsg->msg.msg_namelen = 0;
941 
942 	if (sock->file->f_flags & O_NONBLOCK)
943 		flags |= MSG_DONTWAIT;
944 
945 	err = sock_recvmsg(sock, &kmsg->msg, flags);
946 	*finished = err <= 0;
947 	if (err < 0)
948 		return err;
949 
950 	hdr.msg = (struct io_uring_recvmsg_out) {
951 		.controllen = kmsg->controllen - kmsg->msg.msg_controllen,
952 		.flags = kmsg->msg.msg_flags & ~MSG_CMSG_COMPAT
953 	};
954 
955 	hdr.msg.payloadlen = err;
956 	if (err > kmsg->payloadlen)
957 		err = kmsg->payloadlen;
958 
959 	copy_len = sizeof(struct io_uring_recvmsg_out);
960 	if (kmsg->msg.msg_namelen > kmsg->namelen)
961 		copy_len += kmsg->namelen;
962 	else
963 		copy_len += kmsg->msg.msg_namelen;
964 
965 	/*
966 	 *      "fromlen shall refer to the value before truncation.."
967 	 *                      1003.1g
968 	 */
969 	hdr.msg.namelen = kmsg->msg.msg_namelen;
970 
971 	/* ensure that there is no gap between hdr and sockaddr_storage */
972 	BUILD_BUG_ON(offsetof(struct io_recvmsg_multishot_hdr, addr) !=
973 		     sizeof(struct io_uring_recvmsg_out));
974 	if (copy_to_user(io->buf, &hdr, copy_len)) {
975 		*finished = true;
976 		return -EFAULT;
977 	}
978 
979 	return sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
980 			kmsg->controllen + err;
981 }
982 
io_recvmsg(struct io_kiocb * req,unsigned int issue_flags)983 int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
984 {
985 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
986 	struct io_async_msghdr *kmsg = req->async_data;
987 	struct socket *sock;
988 	unsigned flags;
989 	int ret, min_ret = 0;
990 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
991 	bool mshot_finished = true;
992 
993 	sock = sock_from_file(req->file);
994 	if (unlikely(!sock))
995 		return -ENOTSOCK;
996 
997 	if (!(req->flags & REQ_F_POLLED) &&
998 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
999 		return -EAGAIN;
1000 
1001 	flags = sr->msg_flags;
1002 	if (force_nonblock)
1003 		flags |= MSG_DONTWAIT;
1004 
1005 retry_multishot:
1006 	if (io_do_buffer_select(req)) {
1007 		void __user *buf;
1008 		size_t len = sr->len;
1009 
1010 		buf = io_buffer_select(req, &len, issue_flags);
1011 		if (!buf)
1012 			return -ENOBUFS;
1013 
1014 		if (req->flags & REQ_F_APOLL_MULTISHOT) {
1015 			ret = io_recvmsg_prep_multishot(kmsg, sr, &buf, &len);
1016 			if (ret) {
1017 				io_kbuf_recycle(req, issue_flags);
1018 				return ret;
1019 			}
1020 		}
1021 
1022 		iov_iter_ubuf(&kmsg->msg.msg_iter, ITER_DEST, buf, len);
1023 	}
1024 
1025 	kmsg->msg.msg_get_inq = 1;
1026 	kmsg->msg.msg_inq = -1;
1027 	if (req->flags & REQ_F_APOLL_MULTISHOT) {
1028 		ret = io_recvmsg_multishot(sock, sr, kmsg, flags,
1029 					   &mshot_finished);
1030 	} else {
1031 		/* disable partial retry for recvmsg with cmsg attached */
1032 		if (flags & MSG_WAITALL && !kmsg->msg.msg_controllen)
1033 			min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1034 
1035 		ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg,
1036 					 kmsg->uaddr, flags);
1037 	}
1038 
1039 	if (ret < min_ret) {
1040 		if (ret == -EAGAIN && force_nonblock) {
1041 			if (issue_flags & IO_URING_F_MULTISHOT) {
1042 				io_kbuf_recycle(req, issue_flags);
1043 				return IOU_ISSUE_SKIP_COMPLETE;
1044 			}
1045 			return -EAGAIN;
1046 		}
1047 		if (ret > 0 && io_net_retry(sock, flags)) {
1048 			sr->done_io += ret;
1049 			req->flags |= REQ_F_BL_NO_RECYCLE;
1050 			return -EAGAIN;
1051 		}
1052 		if (ret == -ERESTARTSYS)
1053 			ret = -EINTR;
1054 		req_set_fail(req);
1055 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1056 		req_set_fail(req);
1057 	}
1058 
1059 	if (ret > 0)
1060 		ret += sr->done_io;
1061 	else if (sr->done_io)
1062 		ret = sr->done_io;
1063 	else
1064 		io_kbuf_recycle(req, issue_flags);
1065 
1066 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1067 		goto retry_multishot;
1068 
1069 	return ret;
1070 }
1071 
io_recv_buf_select(struct io_kiocb * req,struct io_async_msghdr * kmsg,size_t * len,unsigned int issue_flags)1072 static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg,
1073 			      size_t *len, unsigned int issue_flags)
1074 {
1075 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1076 	int ret;
1077 
1078 	/*
1079 	 * If the ring isn't locked, then don't use the peek interface
1080 	 * to grab multiple buffers as we will lock/unlock between
1081 	 * this selection and posting the buffers.
1082 	 */
1083 	if (!(issue_flags & IO_URING_F_UNLOCKED) &&
1084 	    sr->flags & IORING_RECVSEND_BUNDLE) {
1085 		struct buf_sel_arg arg = {
1086 			.iovs = &kmsg->fast_iov,
1087 			.nr_iovs = 1,
1088 			.mode = KBUF_MODE_EXPAND,
1089 		};
1090 
1091 		if (kmsg->free_iov) {
1092 			arg.nr_iovs = kmsg->free_iov_nr;
1093 			arg.iovs = kmsg->free_iov;
1094 			arg.mode |= KBUF_MODE_FREE;
1095 		}
1096 
1097 		if (kmsg->msg.msg_inq > 0)
1098 			arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq);
1099 
1100 		ret = io_buffers_peek(req, &arg);
1101 		if (unlikely(ret < 0))
1102 			return ret;
1103 
1104 		/* special case 1 vec, can be a fast path */
1105 		if (ret == 1) {
1106 			sr->buf = arg.iovs[0].iov_base;
1107 			sr->len = arg.iovs[0].iov_len;
1108 			goto map_ubuf;
1109 		}
1110 		iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, arg.iovs, ret,
1111 				arg.out_len);
1112 		if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) {
1113 			kmsg->free_iov_nr = ret;
1114 			kmsg->free_iov = arg.iovs;
1115 			req->flags |= REQ_F_NEED_CLEANUP;
1116 		}
1117 	} else {
1118 		void __user *buf;
1119 
1120 		*len = sr->len;
1121 		buf = io_buffer_select(req, len, issue_flags);
1122 		if (!buf)
1123 			return -ENOBUFS;
1124 		sr->buf = buf;
1125 		sr->len = *len;
1126 map_ubuf:
1127 		ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
1128 				  &kmsg->msg.msg_iter);
1129 		if (unlikely(ret))
1130 			return ret;
1131 	}
1132 
1133 	return 0;
1134 }
1135 
io_recv(struct io_kiocb * req,unsigned int issue_flags)1136 int io_recv(struct io_kiocb *req, unsigned int issue_flags)
1137 {
1138 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1139 	struct io_async_msghdr *kmsg = req->async_data;
1140 	struct socket *sock;
1141 	unsigned flags;
1142 	int ret, min_ret = 0;
1143 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1144 	size_t len = sr->len;
1145 	bool mshot_finished;
1146 
1147 	if (!(req->flags & REQ_F_POLLED) &&
1148 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1149 		return -EAGAIN;
1150 
1151 	sock = sock_from_file(req->file);
1152 	if (unlikely(!sock))
1153 		return -ENOTSOCK;
1154 
1155 	flags = sr->msg_flags;
1156 	if (force_nonblock)
1157 		flags |= MSG_DONTWAIT;
1158 
1159 retry_multishot:
1160 	if (io_do_buffer_select(req)) {
1161 		ret = io_recv_buf_select(req, kmsg, &len, issue_flags);
1162 		if (unlikely(ret)) {
1163 			kmsg->msg.msg_inq = -1;
1164 			goto out_free;
1165 		}
1166 		sr->buf = NULL;
1167 	}
1168 
1169 	kmsg->msg.msg_flags = 0;
1170 	kmsg->msg.msg_inq = -1;
1171 
1172 	if (flags & MSG_WAITALL)
1173 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1174 
1175 	ret = sock_recvmsg(sock, &kmsg->msg, flags);
1176 	if (ret < min_ret) {
1177 		if (ret == -EAGAIN && force_nonblock) {
1178 			if (issue_flags & IO_URING_F_MULTISHOT) {
1179 				io_kbuf_recycle(req, issue_flags);
1180 				return IOU_ISSUE_SKIP_COMPLETE;
1181 			}
1182 
1183 			return -EAGAIN;
1184 		}
1185 		if (ret > 0 && io_net_retry(sock, flags)) {
1186 			sr->len -= ret;
1187 			sr->buf += ret;
1188 			sr->done_io += ret;
1189 			req->flags |= REQ_F_BL_NO_RECYCLE;
1190 			return -EAGAIN;
1191 		}
1192 		if (ret == -ERESTARTSYS)
1193 			ret = -EINTR;
1194 		req_set_fail(req);
1195 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1196 out_free:
1197 		req_set_fail(req);
1198 	}
1199 
1200 	mshot_finished = ret <= 0;
1201 	if (ret > 0)
1202 		ret += sr->done_io;
1203 	else if (sr->done_io)
1204 		ret = sr->done_io;
1205 	else
1206 		io_kbuf_recycle(req, issue_flags);
1207 
1208 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1209 		goto retry_multishot;
1210 
1211 	return ret;
1212 }
1213 
io_send_zc_cleanup(struct io_kiocb * req)1214 void io_send_zc_cleanup(struct io_kiocb *req)
1215 {
1216 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1217 	struct io_async_msghdr *io = req->async_data;
1218 
1219 	if (req_has_async_data(req))
1220 		io_netmsg_iovec_free(io);
1221 	if (zc->notif) {
1222 		io_notif_flush(zc->notif);
1223 		zc->notif = NULL;
1224 	}
1225 }
1226 
1227 #define IO_ZC_FLAGS_COMMON (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_FIXED_BUF)
1228 #define IO_ZC_FLAGS_VALID  (IO_ZC_FLAGS_COMMON | IORING_SEND_ZC_REPORT_USAGE)
1229 
io_send_zc_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1230 int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1231 {
1232 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1233 	struct io_ring_ctx *ctx = req->ctx;
1234 	struct io_kiocb *notif;
1235 
1236 	zc->done_io = 0;
1237 	req->flags |= REQ_F_POLL_NO_LAZY;
1238 
1239 	if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3)))
1240 		return -EINVAL;
1241 	/* we don't support IOSQE_CQE_SKIP_SUCCESS just yet */
1242 	if (req->flags & REQ_F_CQE_SKIP)
1243 		return -EINVAL;
1244 
1245 	notif = zc->notif = io_alloc_notif(ctx);
1246 	if (!notif)
1247 		return -ENOMEM;
1248 	notif->cqe.user_data = req->cqe.user_data;
1249 	notif->cqe.res = 0;
1250 	notif->cqe.flags = IORING_CQE_F_NOTIF;
1251 	req->flags |= REQ_F_NEED_CLEANUP;
1252 
1253 	zc->flags = READ_ONCE(sqe->ioprio);
1254 	if (unlikely(zc->flags & ~IO_ZC_FLAGS_COMMON)) {
1255 		if (zc->flags & ~IO_ZC_FLAGS_VALID)
1256 			return -EINVAL;
1257 		if (zc->flags & IORING_SEND_ZC_REPORT_USAGE) {
1258 			struct io_notif_data *nd = io_notif_to_data(notif);
1259 
1260 			nd->zc_report = true;
1261 			nd->zc_used = false;
1262 			nd->zc_copied = false;
1263 		}
1264 	}
1265 
1266 	if (req->opcode != IORING_OP_SEND_ZC) {
1267 		if (unlikely(sqe->addr2 || sqe->file_index))
1268 			return -EINVAL;
1269 		if (unlikely(zc->flags & IORING_RECVSEND_FIXED_BUF))
1270 			return -EINVAL;
1271 	}
1272 
1273 	zc->len = READ_ONCE(sqe->len);
1274 	zc->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL | MSG_ZEROCOPY;
1275 	zc->buf_index = READ_ONCE(sqe->buf_index);
1276 	if (zc->msg_flags & MSG_DONTWAIT)
1277 		req->flags |= REQ_F_NOWAIT;
1278 
1279 #ifdef CONFIG_COMPAT
1280 	if (req->ctx->compat)
1281 		zc->msg_flags |= MSG_CMSG_COMPAT;
1282 #endif
1283 	if (unlikely(!io_msg_alloc_async(req)))
1284 		return -ENOMEM;
1285 	if (req->opcode != IORING_OP_SENDMSG_ZC)
1286 		return io_send_setup(req, sqe);
1287 	return io_sendmsg_setup(req, sqe);
1288 }
1289 
io_sg_from_iter_iovec(struct sk_buff * skb,struct iov_iter * from,size_t length)1290 static int io_sg_from_iter_iovec(struct sk_buff *skb,
1291 				 struct iov_iter *from, size_t length)
1292 {
1293 	skb_zcopy_downgrade_managed(skb);
1294 	return zerocopy_fill_skb_from_iter(skb, from, length);
1295 }
1296 
io_sg_from_iter(struct sk_buff * skb,struct iov_iter * from,size_t length)1297 static int io_sg_from_iter(struct sk_buff *skb,
1298 			   struct iov_iter *from, size_t length)
1299 {
1300 	struct skb_shared_info *shinfo = skb_shinfo(skb);
1301 	int frag = shinfo->nr_frags;
1302 	int ret = 0;
1303 	struct bvec_iter bi;
1304 	ssize_t copied = 0;
1305 	unsigned long truesize = 0;
1306 
1307 	if (!frag)
1308 		shinfo->flags |= SKBFL_MANAGED_FRAG_REFS;
1309 	else if (unlikely(!skb_zcopy_managed(skb)))
1310 		return zerocopy_fill_skb_from_iter(skb, from, length);
1311 
1312 	bi.bi_size = min(from->count, length);
1313 	bi.bi_bvec_done = from->iov_offset;
1314 	bi.bi_idx = 0;
1315 
1316 	while (bi.bi_size && frag < MAX_SKB_FRAGS) {
1317 		struct bio_vec v = mp_bvec_iter_bvec(from->bvec, bi);
1318 
1319 		copied += v.bv_len;
1320 		truesize += PAGE_ALIGN(v.bv_len + v.bv_offset);
1321 		__skb_fill_page_desc_noacc(shinfo, frag++, v.bv_page,
1322 					   v.bv_offset, v.bv_len);
1323 		bvec_iter_advance_single(from->bvec, &bi, v.bv_len);
1324 	}
1325 	if (bi.bi_size)
1326 		ret = -EMSGSIZE;
1327 
1328 	shinfo->nr_frags = frag;
1329 	from->bvec += bi.bi_idx;
1330 	from->nr_segs -= bi.bi_idx;
1331 	from->count -= copied;
1332 	from->iov_offset = bi.bi_bvec_done;
1333 
1334 	skb->data_len += copied;
1335 	skb->len += copied;
1336 	skb->truesize += truesize;
1337 	return ret;
1338 }
1339 
io_send_zc_import(struct io_kiocb * req,unsigned int issue_flags)1340 static int io_send_zc_import(struct io_kiocb *req, unsigned int issue_flags)
1341 {
1342 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1343 	struct io_async_msghdr *kmsg = req->async_data;
1344 	int ret;
1345 
1346 	if (sr->flags & IORING_RECVSEND_FIXED_BUF) {
1347 		struct io_ring_ctx *ctx = req->ctx;
1348 		struct io_rsrc_node *node;
1349 
1350 		ret = -EFAULT;
1351 		io_ring_submit_lock(ctx, issue_flags);
1352 		node = io_rsrc_node_lookup(&ctx->buf_table, sr->buf_index);
1353 		if (node) {
1354 			io_req_assign_buf_node(sr->notif, node);
1355 			ret = 0;
1356 		}
1357 		io_ring_submit_unlock(ctx, issue_flags);
1358 
1359 		if (unlikely(ret))
1360 			return ret;
1361 
1362 		ret = io_import_fixed(ITER_SOURCE, &kmsg->msg.msg_iter,
1363 					node->buf, (u64)(uintptr_t)sr->buf,
1364 					sr->len);
1365 		if (unlikely(ret))
1366 			return ret;
1367 		kmsg->msg.sg_from_iter = io_sg_from_iter;
1368 	} else {
1369 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len, &kmsg->msg.msg_iter);
1370 		if (unlikely(ret))
1371 			return ret;
1372 		ret = io_notif_account_mem(sr->notif, sr->len);
1373 		if (unlikely(ret))
1374 			return ret;
1375 		kmsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1376 	}
1377 
1378 	return ret;
1379 }
1380 
io_send_zc(struct io_kiocb * req,unsigned int issue_flags)1381 int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
1382 {
1383 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1384 	struct io_async_msghdr *kmsg = req->async_data;
1385 	struct socket *sock;
1386 	unsigned msg_flags;
1387 	int ret, min_ret = 0;
1388 
1389 	sock = sock_from_file(req->file);
1390 	if (unlikely(!sock))
1391 		return -ENOTSOCK;
1392 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1393 		return -EOPNOTSUPP;
1394 
1395 	if (!(req->flags & REQ_F_POLLED) &&
1396 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1397 		return -EAGAIN;
1398 
1399 	if (!zc->done_io) {
1400 		ret = io_send_zc_import(req, issue_flags);
1401 		if (unlikely(ret))
1402 			return ret;
1403 	}
1404 
1405 	msg_flags = zc->msg_flags;
1406 	if (issue_flags & IO_URING_F_NONBLOCK)
1407 		msg_flags |= MSG_DONTWAIT;
1408 	if (msg_flags & MSG_WAITALL)
1409 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1410 	msg_flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
1411 
1412 	kmsg->msg.msg_flags = msg_flags;
1413 	kmsg->msg.msg_ubuf = &io_notif_to_data(zc->notif)->uarg;
1414 	ret = sock_sendmsg(sock, &kmsg->msg);
1415 
1416 	if (unlikely(ret < min_ret)) {
1417 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1418 			return -EAGAIN;
1419 
1420 		if (ret > 0 && io_net_retry(sock, kmsg->msg.msg_flags)) {
1421 			zc->len -= ret;
1422 			zc->buf += ret;
1423 			zc->done_io += ret;
1424 			req->flags |= REQ_F_BL_NO_RECYCLE;
1425 			return -EAGAIN;
1426 		}
1427 		if (ret == -ERESTARTSYS)
1428 			ret = -EINTR;
1429 		req_set_fail(req);
1430 	}
1431 
1432 	if (ret >= 0)
1433 		ret += zc->done_io;
1434 	else if (zc->done_io)
1435 		ret = zc->done_io;
1436 
1437 	/*
1438 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1439 	 * flushing notif to io_send_zc_cleanup()
1440 	 */
1441 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1442 		io_notif_flush(zc->notif);
1443 		io_req_msg_cleanup(req, 0);
1444 	}
1445 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1446 	return IOU_OK;
1447 }
1448 
io_sendmsg_zc(struct io_kiocb * req,unsigned int issue_flags)1449 int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags)
1450 {
1451 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1452 	struct io_async_msghdr *kmsg = req->async_data;
1453 	struct socket *sock;
1454 	unsigned flags;
1455 	int ret, min_ret = 0;
1456 
1457 	sock = sock_from_file(req->file);
1458 	if (unlikely(!sock))
1459 		return -ENOTSOCK;
1460 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1461 		return -EOPNOTSUPP;
1462 
1463 	if (!(req->flags & REQ_F_POLLED) &&
1464 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1465 		return -EAGAIN;
1466 
1467 	flags = sr->msg_flags;
1468 	if (issue_flags & IO_URING_F_NONBLOCK)
1469 		flags |= MSG_DONTWAIT;
1470 	if (flags & MSG_WAITALL)
1471 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1472 
1473 	kmsg->msg.msg_control_user = sr->msg_control;
1474 	kmsg->msg.msg_ubuf = &io_notif_to_data(sr->notif)->uarg;
1475 	kmsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1476 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
1477 
1478 	if (unlikely(ret < min_ret)) {
1479 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1480 			return -EAGAIN;
1481 
1482 		if (ret > 0 && io_net_retry(sock, flags)) {
1483 			sr->done_io += ret;
1484 			req->flags |= REQ_F_BL_NO_RECYCLE;
1485 			return -EAGAIN;
1486 		}
1487 		if (ret == -ERESTARTSYS)
1488 			ret = -EINTR;
1489 		req_set_fail(req);
1490 	}
1491 
1492 	if (ret >= 0)
1493 		ret += sr->done_io;
1494 	else if (sr->done_io)
1495 		ret = sr->done_io;
1496 
1497 	/*
1498 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1499 	 * flushing notif to io_send_zc_cleanup()
1500 	 */
1501 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1502 		io_notif_flush(sr->notif);
1503 		io_req_msg_cleanup(req, 0);
1504 	}
1505 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1506 	return IOU_OK;
1507 }
1508 
io_sendrecv_fail(struct io_kiocb * req)1509 void io_sendrecv_fail(struct io_kiocb *req)
1510 {
1511 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1512 
1513 	if (sr->done_io)
1514 		req->cqe.res = sr->done_io;
1515 
1516 	if ((req->flags & REQ_F_NEED_CLEANUP) &&
1517 	    (req->opcode == IORING_OP_SEND_ZC || req->opcode == IORING_OP_SENDMSG_ZC))
1518 		req->cqe.flags |= IORING_CQE_F_MORE;
1519 }
1520 
1521 #define ACCEPT_FLAGS	(IORING_ACCEPT_MULTISHOT | IORING_ACCEPT_DONTWAIT | \
1522 			 IORING_ACCEPT_POLL_FIRST)
1523 
io_accept_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1524 int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1525 {
1526 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1527 
1528 	if (sqe->len || sqe->buf_index)
1529 		return -EINVAL;
1530 
1531 	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1532 	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
1533 	accept->flags = READ_ONCE(sqe->accept_flags);
1534 	accept->nofile = rlimit(RLIMIT_NOFILE);
1535 	accept->iou_flags = READ_ONCE(sqe->ioprio);
1536 	if (accept->iou_flags & ~ACCEPT_FLAGS)
1537 		return -EINVAL;
1538 
1539 	accept->file_slot = READ_ONCE(sqe->file_index);
1540 	if (accept->file_slot) {
1541 		if (accept->flags & SOCK_CLOEXEC)
1542 			return -EINVAL;
1543 		if (accept->iou_flags & IORING_ACCEPT_MULTISHOT &&
1544 		    accept->file_slot != IORING_FILE_INDEX_ALLOC)
1545 			return -EINVAL;
1546 	}
1547 	if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1548 		return -EINVAL;
1549 	if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
1550 		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1551 	if (accept->iou_flags & IORING_ACCEPT_MULTISHOT)
1552 		req->flags |= REQ_F_APOLL_MULTISHOT;
1553 	if (accept->iou_flags & IORING_ACCEPT_DONTWAIT)
1554 		req->flags |= REQ_F_NOWAIT;
1555 	return 0;
1556 }
1557 
io_accept(struct io_kiocb * req,unsigned int issue_flags)1558 int io_accept(struct io_kiocb *req, unsigned int issue_flags)
1559 {
1560 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1561 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1562 	bool fixed = !!accept->file_slot;
1563 	struct proto_accept_arg arg = {
1564 		.flags = force_nonblock ? O_NONBLOCK : 0,
1565 	};
1566 	struct file *file;
1567 	unsigned cflags;
1568 	int ret, fd;
1569 
1570 	if (!(req->flags & REQ_F_POLLED) &&
1571 	    accept->iou_flags & IORING_ACCEPT_POLL_FIRST)
1572 		return -EAGAIN;
1573 
1574 retry:
1575 	if (!fixed) {
1576 		fd = __get_unused_fd_flags(accept->flags, accept->nofile);
1577 		if (unlikely(fd < 0))
1578 			return fd;
1579 	}
1580 	arg.err = 0;
1581 	arg.is_empty = -1;
1582 	file = do_accept(req->file, &arg, accept->addr, accept->addr_len,
1583 			 accept->flags);
1584 	if (IS_ERR(file)) {
1585 		if (!fixed)
1586 			put_unused_fd(fd);
1587 		ret = PTR_ERR(file);
1588 		if (ret == -EAGAIN && force_nonblock &&
1589 		    !(accept->iou_flags & IORING_ACCEPT_DONTWAIT)) {
1590 			/*
1591 			 * if it's multishot and polled, we don't need to
1592 			 * return EAGAIN to arm the poll infra since it
1593 			 * has already been done
1594 			 */
1595 			if (issue_flags & IO_URING_F_MULTISHOT)
1596 				return IOU_ISSUE_SKIP_COMPLETE;
1597 			return ret;
1598 		}
1599 		if (ret == -ERESTARTSYS)
1600 			ret = -EINTR;
1601 		req_set_fail(req);
1602 	} else if (!fixed) {
1603 		fd_install(fd, file);
1604 		ret = fd;
1605 	} else {
1606 		ret = io_fixed_fd_install(req, issue_flags, file,
1607 						accept->file_slot);
1608 	}
1609 
1610 	cflags = 0;
1611 	if (!arg.is_empty)
1612 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
1613 
1614 	if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
1615 		io_req_set_res(req, ret, cflags);
1616 		return IOU_OK;
1617 	}
1618 
1619 	if (ret < 0)
1620 		return ret;
1621 	if (io_req_post_cqe(req, ret, cflags | IORING_CQE_F_MORE)) {
1622 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || arg.is_empty == -1)
1623 			goto retry;
1624 		if (issue_flags & IO_URING_F_MULTISHOT)
1625 			return IOU_ISSUE_SKIP_COMPLETE;
1626 		return -EAGAIN;
1627 	}
1628 
1629 	io_req_set_res(req, ret, cflags);
1630 	return IOU_STOP_MULTISHOT;
1631 }
1632 
io_socket_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1633 int io_socket_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1634 {
1635 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1636 
1637 	if (sqe->addr || sqe->rw_flags || sqe->buf_index)
1638 		return -EINVAL;
1639 
1640 	sock->domain = READ_ONCE(sqe->fd);
1641 	sock->type = READ_ONCE(sqe->off);
1642 	sock->protocol = READ_ONCE(sqe->len);
1643 	sock->file_slot = READ_ONCE(sqe->file_index);
1644 	sock->nofile = rlimit(RLIMIT_NOFILE);
1645 
1646 	sock->flags = sock->type & ~SOCK_TYPE_MASK;
1647 	if (sock->file_slot && (sock->flags & SOCK_CLOEXEC))
1648 		return -EINVAL;
1649 	if (sock->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1650 		return -EINVAL;
1651 	return 0;
1652 }
1653 
io_socket(struct io_kiocb * req,unsigned int issue_flags)1654 int io_socket(struct io_kiocb *req, unsigned int issue_flags)
1655 {
1656 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1657 	bool fixed = !!sock->file_slot;
1658 	struct file *file;
1659 	int ret, fd;
1660 
1661 	if (!fixed) {
1662 		fd = __get_unused_fd_flags(sock->flags, sock->nofile);
1663 		if (unlikely(fd < 0))
1664 			return fd;
1665 	}
1666 	file = __sys_socket_file(sock->domain, sock->type, sock->protocol);
1667 	if (IS_ERR(file)) {
1668 		if (!fixed)
1669 			put_unused_fd(fd);
1670 		ret = PTR_ERR(file);
1671 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1672 			return -EAGAIN;
1673 		if (ret == -ERESTARTSYS)
1674 			ret = -EINTR;
1675 		req_set_fail(req);
1676 	} else if (!fixed) {
1677 		fd_install(fd, file);
1678 		ret = fd;
1679 	} else {
1680 		ret = io_fixed_fd_install(req, issue_flags, file,
1681 					    sock->file_slot);
1682 	}
1683 	io_req_set_res(req, ret, 0);
1684 	return IOU_OK;
1685 }
1686 
io_connect_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1687 int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1688 {
1689 	struct io_connect *conn = io_kiocb_to_cmd(req, struct io_connect);
1690 	struct io_async_msghdr *io;
1691 
1692 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1693 		return -EINVAL;
1694 
1695 	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1696 	conn->addr_len =  READ_ONCE(sqe->addr2);
1697 	conn->in_progress = conn->seen_econnaborted = false;
1698 
1699 	io = io_msg_alloc_async(req);
1700 	if (unlikely(!io))
1701 		return -ENOMEM;
1702 
1703 	return move_addr_to_kernel(conn->addr, conn->addr_len, &io->addr);
1704 }
1705 
io_connect(struct io_kiocb * req,unsigned int issue_flags)1706 int io_connect(struct io_kiocb *req, unsigned int issue_flags)
1707 {
1708 	struct io_connect *connect = io_kiocb_to_cmd(req, struct io_connect);
1709 	struct io_async_msghdr *io = req->async_data;
1710 	unsigned file_flags;
1711 	int ret;
1712 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1713 
1714 	if (unlikely(req->flags & REQ_F_FAIL)) {
1715 		ret = -ECONNRESET;
1716 		goto out;
1717 	}
1718 
1719 	file_flags = force_nonblock ? O_NONBLOCK : 0;
1720 
1721 	ret = __sys_connect_file(req->file, &io->addr, connect->addr_len,
1722 				 file_flags);
1723 	if ((ret == -EAGAIN || ret == -EINPROGRESS || ret == -ECONNABORTED)
1724 	    && force_nonblock) {
1725 		if (ret == -EINPROGRESS) {
1726 			connect->in_progress = true;
1727 		} else if (ret == -ECONNABORTED) {
1728 			if (connect->seen_econnaborted)
1729 				goto out;
1730 			connect->seen_econnaborted = true;
1731 		}
1732 		return -EAGAIN;
1733 	}
1734 	if (connect->in_progress) {
1735 		/*
1736 		 * At least bluetooth will return -EBADFD on a re-connect
1737 		 * attempt, and it's (supposedly) also valid to get -EISCONN
1738 		 * which means the previous result is good. For both of these,
1739 		 * grab the sock_error() and use that for the completion.
1740 		 */
1741 		if (ret == -EBADFD || ret == -EISCONN)
1742 			ret = sock_error(sock_from_file(req->file)->sk);
1743 	}
1744 	if (ret == -ERESTARTSYS)
1745 		ret = -EINTR;
1746 out:
1747 	if (ret < 0)
1748 		req_set_fail(req);
1749 	io_req_msg_cleanup(req, issue_flags);
1750 	io_req_set_res(req, ret, 0);
1751 	return IOU_OK;
1752 }
1753 
io_bind_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1754 int io_bind_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1755 {
1756 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1757 	struct sockaddr __user *uaddr;
1758 	struct io_async_msghdr *io;
1759 
1760 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1761 		return -EINVAL;
1762 
1763 	uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1764 	bind->addr_len =  READ_ONCE(sqe->addr2);
1765 
1766 	io = io_msg_alloc_async(req);
1767 	if (unlikely(!io))
1768 		return -ENOMEM;
1769 	return move_addr_to_kernel(uaddr, bind->addr_len, &io->addr);
1770 }
1771 
io_bind(struct io_kiocb * req,unsigned int issue_flags)1772 int io_bind(struct io_kiocb *req, unsigned int issue_flags)
1773 {
1774 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1775 	struct io_async_msghdr *io = req->async_data;
1776 	struct socket *sock;
1777 	int ret;
1778 
1779 	sock = sock_from_file(req->file);
1780 	if (unlikely(!sock))
1781 		return -ENOTSOCK;
1782 
1783 	ret = __sys_bind_socket(sock, &io->addr, bind->addr_len);
1784 	if (ret < 0)
1785 		req_set_fail(req);
1786 	io_req_set_res(req, ret, 0);
1787 	return 0;
1788 }
1789 
io_listen_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1790 int io_listen_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1791 {
1792 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1793 
1794 	if (sqe->addr || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in || sqe->addr2)
1795 		return -EINVAL;
1796 
1797 	listen->backlog = READ_ONCE(sqe->len);
1798 	return 0;
1799 }
1800 
io_listen(struct io_kiocb * req,unsigned int issue_flags)1801 int io_listen(struct io_kiocb *req, unsigned int issue_flags)
1802 {
1803 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1804 	struct socket *sock;
1805 	int ret;
1806 
1807 	sock = sock_from_file(req->file);
1808 	if (unlikely(!sock))
1809 		return -ENOTSOCK;
1810 
1811 	ret = __sys_listen_socket(sock, listen->backlog);
1812 	if (ret < 0)
1813 		req_set_fail(req);
1814 	io_req_set_res(req, ret, 0);
1815 	return 0;
1816 }
1817 
io_netmsg_cache_free(const void * entry)1818 void io_netmsg_cache_free(const void *entry)
1819 {
1820 	struct io_async_msghdr *kmsg = (struct io_async_msghdr *) entry;
1821 
1822 	if (kmsg->free_iov)
1823 		io_netmsg_iovec_free(kmsg);
1824 	kfree(kmsg);
1825 }
1826 #endif
1827