1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/errno.h>
4 #include <linux/file.h>
5 #include <linux/slab.h>
6 #include <linux/net.h>
7 #include <linux/compat.h>
8 #include <net/compat.h>
9 #include <linux/io_uring.h>
10 
11 #include <uapi/linux/io_uring.h>
12 
13 #include "io_uring.h"
14 #include "kbuf.h"
15 #include "alloc_cache.h"
16 #include "net.h"
17 #include "notif.h"
18 #include "rsrc.h"
19 #include "zcrx.h"
20 
21 #if defined(CONFIG_NET)
22 struct io_shutdown {
23 	struct file			*file;
24 	int				how;
25 };
26 
27 struct io_accept {
28 	struct file			*file;
29 	struct sockaddr __user		*addr;
30 	int __user			*addr_len;
31 	int				flags;
32 	int				iou_flags;
33 	u32				file_slot;
34 	unsigned long			nofile;
35 };
36 
37 struct io_socket {
38 	struct file			*file;
39 	int				domain;
40 	int				type;
41 	int				protocol;
42 	int				flags;
43 	u32				file_slot;
44 	unsigned long			nofile;
45 };
46 
47 struct io_connect {
48 	struct file			*file;
49 	struct sockaddr __user		*addr;
50 	int				addr_len;
51 	bool				in_progress;
52 	bool				seen_econnaborted;
53 };
54 
55 struct io_bind {
56 	struct file			*file;
57 	int				addr_len;
58 };
59 
60 struct io_listen {
61 	struct file			*file;
62 	int				backlog;
63 };
64 
65 struct io_sr_msg {
66 	struct file			*file;
67 	union {
68 		struct compat_msghdr __user	*umsg_compat;
69 		struct user_msghdr __user	*umsg;
70 		void __user			*buf;
71 	};
72 	int				len;
73 	unsigned			done_io;
74 	unsigned			msg_flags;
75 	unsigned			nr_multishot_loops;
76 	u16				flags;
77 	/* initialised and used only by !msg send variants */
78 	u16				buf_group;
79 	bool				retry;
80 	void __user			*msg_control;
81 	/* used only for send zerocopy */
82 	struct io_kiocb 		*notif;
83 };
84 
85 /*
86  * Number of times we'll try and do receives if there's more data. If we
87  * exceed this limit, then add us to the back of the queue and retry from
88  * there. This helps fairness between flooding clients.
89  */
90 #define MULTISHOT_MAX_RETRY	32
91 
92 struct io_recvzc {
93 	struct file			*file;
94 	unsigned			msg_flags;
95 	u16				flags;
96 	u32				len;
97 	struct io_zcrx_ifq		*ifq;
98 };
99 
100 static int io_sg_from_iter_iovec(struct sk_buff *skb,
101 				 struct iov_iter *from, size_t length);
102 static int io_sg_from_iter(struct sk_buff *skb,
103 			   struct iov_iter *from, size_t length);
104 
io_shutdown_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)105 int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
106 {
107 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
108 
109 	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
110 		     sqe->buf_index || sqe->splice_fd_in))
111 		return -EINVAL;
112 
113 	shutdown->how = READ_ONCE(sqe->len);
114 	req->flags |= REQ_F_FORCE_ASYNC;
115 	return 0;
116 }
117 
io_shutdown(struct io_kiocb * req,unsigned int issue_flags)118 int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
119 {
120 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
121 	struct socket *sock;
122 	int ret;
123 
124 	WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
125 
126 	sock = sock_from_file(req->file);
127 	if (unlikely(!sock))
128 		return -ENOTSOCK;
129 
130 	ret = __sys_shutdown_sock(sock, shutdown->how);
131 	io_req_set_res(req, ret, 0);
132 	return IOU_OK;
133 }
134 
io_net_retry(struct socket * sock,int flags)135 static bool io_net_retry(struct socket *sock, int flags)
136 {
137 	if (!(flags & MSG_WAITALL))
138 		return false;
139 	return sock->type == SOCK_STREAM || sock->type == SOCK_SEQPACKET;
140 }
141 
io_netmsg_iovec_free(struct io_async_msghdr * kmsg)142 static void io_netmsg_iovec_free(struct io_async_msghdr *kmsg)
143 {
144 	if (kmsg->vec.iovec)
145 		io_vec_free(&kmsg->vec);
146 }
147 
io_netmsg_recycle(struct io_kiocb * req,unsigned int issue_flags)148 static void io_netmsg_recycle(struct io_kiocb *req, unsigned int issue_flags)
149 {
150 	struct io_async_msghdr *hdr = req->async_data;
151 
152 	/* can't recycle, ensure we free the iovec if we have one */
153 	if (unlikely(issue_flags & IO_URING_F_UNLOCKED)) {
154 		io_netmsg_iovec_free(hdr);
155 		return;
156 	}
157 
158 	/* Let normal cleanup path reap it if we fail adding to the cache */
159 	io_alloc_cache_vec_kasan(&hdr->vec);
160 	if (hdr->vec.nr > IO_VEC_CACHE_SOFT_CAP)
161 		io_vec_free(&hdr->vec);
162 
163 	if (io_alloc_cache_put(&req->ctx->netmsg_cache, hdr)) {
164 		req->async_data = NULL;
165 		req->flags &= ~(REQ_F_ASYNC_DATA|REQ_F_NEED_CLEANUP);
166 	}
167 }
168 
io_msg_alloc_async(struct io_kiocb * req)169 static struct io_async_msghdr *io_msg_alloc_async(struct io_kiocb *req)
170 {
171 	struct io_ring_ctx *ctx = req->ctx;
172 	struct io_async_msghdr *hdr;
173 
174 	hdr = io_uring_alloc_async_data(&ctx->netmsg_cache, req);
175 	if (!hdr)
176 		return NULL;
177 
178 	/* If the async data was cached, we might have an iov cached inside. */
179 	if (hdr->vec.iovec)
180 		req->flags |= REQ_F_NEED_CLEANUP;
181 	return hdr;
182 }
183 
io_mshot_prep_retry(struct io_kiocb * req,struct io_async_msghdr * kmsg)184 static inline void io_mshot_prep_retry(struct io_kiocb *req,
185 				       struct io_async_msghdr *kmsg)
186 {
187 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
188 
189 	req->flags &= ~REQ_F_BL_EMPTY;
190 	sr->done_io = 0;
191 	sr->retry = false;
192 	sr->len = 0; /* get from the provided buffer */
193 	req->buf_index = sr->buf_group;
194 }
195 
io_net_import_vec(struct io_kiocb * req,struct io_async_msghdr * iomsg,const struct iovec __user * uiov,unsigned uvec_seg,int ddir)196 static int io_net_import_vec(struct io_kiocb *req, struct io_async_msghdr *iomsg,
197 			     const struct iovec __user *uiov, unsigned uvec_seg,
198 			     int ddir)
199 {
200 	struct iovec *iov;
201 	int ret, nr_segs;
202 
203 	if (iomsg->vec.iovec) {
204 		nr_segs = iomsg->vec.nr;
205 		iov = iomsg->vec.iovec;
206 	} else {
207 		nr_segs = 1;
208 		iov = &iomsg->fast_iov;
209 	}
210 
211 	ret = __import_iovec(ddir, uiov, uvec_seg, nr_segs, &iov,
212 			     &iomsg->msg.msg_iter, io_is_compat(req->ctx));
213 	if (unlikely(ret < 0))
214 		return ret;
215 
216 	if (iov) {
217 		req->flags |= REQ_F_NEED_CLEANUP;
218 		io_vec_reset_iovec(&iomsg->vec, iov, iomsg->msg.msg_iter.nr_segs);
219 	}
220 	return 0;
221 }
222 
io_compat_msg_copy_hdr(struct io_kiocb * req,struct io_async_msghdr * iomsg,struct compat_msghdr * msg,int ddir,struct sockaddr __user ** save_addr)223 static int io_compat_msg_copy_hdr(struct io_kiocb *req,
224 				  struct io_async_msghdr *iomsg,
225 				  struct compat_msghdr *msg, int ddir,
226 				  struct sockaddr __user **save_addr)
227 {
228 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
229 	struct compat_iovec __user *uiov;
230 	int ret;
231 
232 	if (copy_from_user(msg, sr->umsg_compat, sizeof(*msg)))
233 		return -EFAULT;
234 
235 	ret = __get_compat_msghdr(&iomsg->msg, msg, save_addr);
236 	if (ret)
237 		return ret;
238 
239 	uiov = compat_ptr(msg->msg_iov);
240 	if (req->flags & REQ_F_BUFFER_SELECT) {
241 		if (msg->msg_iovlen == 0) {
242 			sr->len = 0;
243 		} else if (msg->msg_iovlen > 1) {
244 			return -EINVAL;
245 		} else {
246 			struct compat_iovec tmp_iov;
247 
248 			if (copy_from_user(&tmp_iov, uiov, sizeof(tmp_iov)))
249 				return -EFAULT;
250 			sr->len = tmp_iov.iov_len;
251 		}
252 	}
253 	return 0;
254 }
255 
io_copy_msghdr_from_user(struct user_msghdr * msg,struct user_msghdr __user * umsg)256 static int io_copy_msghdr_from_user(struct user_msghdr *msg,
257 				    struct user_msghdr __user *umsg)
258 {
259 	if (!user_access_begin(umsg, sizeof(*umsg)))
260 		return -EFAULT;
261 	unsafe_get_user(msg->msg_name, &umsg->msg_name, ua_end);
262 	unsafe_get_user(msg->msg_namelen, &umsg->msg_namelen, ua_end);
263 	unsafe_get_user(msg->msg_iov, &umsg->msg_iov, ua_end);
264 	unsafe_get_user(msg->msg_iovlen, &umsg->msg_iovlen, ua_end);
265 	unsafe_get_user(msg->msg_control, &umsg->msg_control, ua_end);
266 	unsafe_get_user(msg->msg_controllen, &umsg->msg_controllen, ua_end);
267 	user_access_end();
268 	return 0;
269 ua_end:
270 	user_access_end();
271 	return -EFAULT;
272 }
273 
io_msg_copy_hdr(struct io_kiocb * req,struct io_async_msghdr * iomsg,struct user_msghdr * msg,int ddir,struct sockaddr __user ** save_addr)274 static int io_msg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg,
275 			   struct user_msghdr *msg, int ddir,
276 			   struct sockaddr __user **save_addr)
277 {
278 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
279 	struct user_msghdr __user *umsg = sr->umsg;
280 	int ret;
281 
282 	iomsg->msg.msg_name = &iomsg->addr;
283 	iomsg->msg.msg_iter.nr_segs = 0;
284 
285 	if (io_is_compat(req->ctx)) {
286 		struct compat_msghdr cmsg;
287 
288 		ret = io_compat_msg_copy_hdr(req, iomsg, &cmsg, ddir, save_addr);
289 		if (ret)
290 			return ret;
291 
292 		memset(msg, 0, sizeof(*msg));
293 		msg->msg_namelen = cmsg.msg_namelen;
294 		msg->msg_controllen = cmsg.msg_controllen;
295 		msg->msg_iov = compat_ptr(cmsg.msg_iov);
296 		msg->msg_iovlen = cmsg.msg_iovlen;
297 		return 0;
298 	}
299 
300 	ret = io_copy_msghdr_from_user(msg, umsg);
301 	if (unlikely(ret))
302 		return ret;
303 
304 	msg->msg_flags = 0;
305 
306 	ret = __copy_msghdr(&iomsg->msg, msg, save_addr);
307 	if (ret)
308 		return ret;
309 
310 	if (req->flags & REQ_F_BUFFER_SELECT) {
311 		if (msg->msg_iovlen == 0) {
312 			sr->len = 0;
313 		} else if (msg->msg_iovlen > 1) {
314 			return -EINVAL;
315 		} else {
316 			struct iovec __user *uiov = msg->msg_iov;
317 			struct iovec tmp_iov;
318 
319 			if (copy_from_user(&tmp_iov, uiov, sizeof(tmp_iov)))
320 				return -EFAULT;
321 			sr->len = tmp_iov.iov_len;
322 		}
323 	}
324 	return 0;
325 }
326 
io_sendmsg_recvmsg_cleanup(struct io_kiocb * req)327 void io_sendmsg_recvmsg_cleanup(struct io_kiocb *req)
328 {
329 	struct io_async_msghdr *io = req->async_data;
330 
331 	io_netmsg_iovec_free(io);
332 }
333 
io_send_setup(struct io_kiocb * req,const struct io_uring_sqe * sqe)334 static int io_send_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
335 {
336 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
337 	struct io_async_msghdr *kmsg = req->async_data;
338 	void __user *addr;
339 	u16 addr_len;
340 	int ret;
341 
342 	sr->buf = u64_to_user_ptr(READ_ONCE(sqe->addr));
343 
344 	if (READ_ONCE(sqe->__pad3[0]))
345 		return -EINVAL;
346 
347 	kmsg->msg.msg_name = NULL;
348 	kmsg->msg.msg_namelen = 0;
349 	kmsg->msg.msg_control = NULL;
350 	kmsg->msg.msg_controllen = 0;
351 	kmsg->msg.msg_ubuf = NULL;
352 
353 	addr = u64_to_user_ptr(READ_ONCE(sqe->addr2));
354 	addr_len = READ_ONCE(sqe->addr_len);
355 	if (addr) {
356 		ret = move_addr_to_kernel(addr, addr_len, &kmsg->addr);
357 		if (unlikely(ret < 0))
358 			return ret;
359 		kmsg->msg.msg_name = &kmsg->addr;
360 		kmsg->msg.msg_namelen = addr_len;
361 	}
362 	if (sr->flags & IORING_RECVSEND_FIXED_BUF)
363 		return 0;
364 	if (!io_do_buffer_select(req)) {
365 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
366 				  &kmsg->msg.msg_iter);
367 		if (unlikely(ret < 0))
368 			return ret;
369 	}
370 	return 0;
371 }
372 
io_sendmsg_setup(struct io_kiocb * req,const struct io_uring_sqe * sqe)373 static int io_sendmsg_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
374 {
375 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
376 	struct io_async_msghdr *kmsg = req->async_data;
377 	struct user_msghdr msg;
378 	int ret;
379 
380 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
381 	ret = io_msg_copy_hdr(req, kmsg, &msg, ITER_SOURCE, NULL);
382 	if (unlikely(ret))
383 		return ret;
384 	/* save msg_control as sys_sendmsg() overwrites it */
385 	sr->msg_control = kmsg->msg.msg_control_user;
386 
387 	if (sr->flags & IORING_RECVSEND_FIXED_BUF) {
388 		kmsg->msg.msg_iter.nr_segs = msg.msg_iovlen;
389 		return io_prep_reg_iovec(req, &kmsg->vec, msg.msg_iov,
390 					 msg.msg_iovlen);
391 	}
392 	if (req->flags & REQ_F_BUFFER_SELECT)
393 		return 0;
394 	return io_net_import_vec(req, kmsg, msg.msg_iov, msg.msg_iovlen, ITER_SOURCE);
395 }
396 
397 #define SENDMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_BUNDLE)
398 
io_sendmsg_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)399 int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
400 {
401 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
402 
403 	sr->done_io = 0;
404 	sr->retry = false;
405 	sr->len = READ_ONCE(sqe->len);
406 	sr->flags = READ_ONCE(sqe->ioprio);
407 	if (sr->flags & ~SENDMSG_FLAGS)
408 		return -EINVAL;
409 	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
410 	if (sr->msg_flags & MSG_DONTWAIT)
411 		req->flags |= REQ_F_NOWAIT;
412 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
413 		if (req->opcode == IORING_OP_SENDMSG)
414 			return -EINVAL;
415 		if (!(req->flags & REQ_F_BUFFER_SELECT))
416 			return -EINVAL;
417 		sr->msg_flags |= MSG_WAITALL;
418 		sr->buf_group = req->buf_index;
419 		req->buf_list = NULL;
420 		req->flags |= REQ_F_MULTISHOT;
421 	}
422 
423 	if (io_is_compat(req->ctx))
424 		sr->msg_flags |= MSG_CMSG_COMPAT;
425 
426 	if (unlikely(!io_msg_alloc_async(req)))
427 		return -ENOMEM;
428 	if (req->opcode != IORING_OP_SENDMSG)
429 		return io_send_setup(req, sqe);
430 	if (unlikely(sqe->addr2 || sqe->file_index))
431 		return -EINVAL;
432 	return io_sendmsg_setup(req, sqe);
433 }
434 
io_req_msg_cleanup(struct io_kiocb * req,unsigned int issue_flags)435 static void io_req_msg_cleanup(struct io_kiocb *req,
436 			       unsigned int issue_flags)
437 {
438 	io_netmsg_recycle(req, issue_flags);
439 }
440 
441 /*
442  * For bundle completions, we need to figure out how many segments we consumed.
443  * A bundle could be using a single ITER_UBUF if that's all we mapped, or it
444  * could be using an ITER_IOVEC. If the latter, then if we consumed all of
445  * the segments, then it's a trivial questiont o answer. If we have residual
446  * data in the iter, then loop the segments to figure out how much we
447  * transferred.
448  */
io_bundle_nbufs(struct io_async_msghdr * kmsg,int ret)449 static int io_bundle_nbufs(struct io_async_msghdr *kmsg, int ret)
450 {
451 	struct iovec *iov;
452 	int nbufs;
453 
454 	/* no data is always zero segments, and a ubuf is always 1 segment */
455 	if (ret <= 0)
456 		return 0;
457 	if (iter_is_ubuf(&kmsg->msg.msg_iter))
458 		return 1;
459 
460 	iov = kmsg->vec.iovec;
461 	if (!iov)
462 		iov = &kmsg->fast_iov;
463 
464 	/* if all data was transferred, it's basic pointer math */
465 	if (!iov_iter_count(&kmsg->msg.msg_iter))
466 		return iter_iov(&kmsg->msg.msg_iter) - iov;
467 
468 	/* short transfer, count segments */
469 	nbufs = 0;
470 	do {
471 		int this_len = min_t(int, iov[nbufs].iov_len, ret);
472 
473 		nbufs++;
474 		ret -= this_len;
475 	} while (ret);
476 
477 	return nbufs;
478 }
479 
io_send_finish(struct io_kiocb * req,int * ret,struct io_async_msghdr * kmsg,unsigned issue_flags)480 static inline bool io_send_finish(struct io_kiocb *req, int *ret,
481 				  struct io_async_msghdr *kmsg,
482 				  unsigned issue_flags)
483 {
484 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
485 	bool bundle_finished = *ret <= 0;
486 	unsigned int cflags;
487 
488 	if (!(sr->flags & IORING_RECVSEND_BUNDLE)) {
489 		cflags = io_put_kbuf(req, *ret, issue_flags);
490 		goto finish;
491 	}
492 
493 	cflags = io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret), issue_flags);
494 
495 	if (bundle_finished || req->flags & REQ_F_BL_EMPTY)
496 		goto finish;
497 
498 	/*
499 	 * Fill CQE for this receive and see if we should keep trying to
500 	 * receive from this socket.
501 	 */
502 	if (io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
503 		io_mshot_prep_retry(req, kmsg);
504 		return false;
505 	}
506 
507 	/* Otherwise stop bundle and use the current result. */
508 finish:
509 	io_req_set_res(req, *ret, cflags);
510 	*ret = IOU_OK;
511 	return true;
512 }
513 
io_sendmsg(struct io_kiocb * req,unsigned int issue_flags)514 int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
515 {
516 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
517 	struct io_async_msghdr *kmsg = req->async_data;
518 	struct socket *sock;
519 	unsigned flags;
520 	int min_ret = 0;
521 	int ret;
522 
523 	sock = sock_from_file(req->file);
524 	if (unlikely(!sock))
525 		return -ENOTSOCK;
526 
527 	if (!(req->flags & REQ_F_POLLED) &&
528 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
529 		return -EAGAIN;
530 
531 	flags = sr->msg_flags;
532 	if (issue_flags & IO_URING_F_NONBLOCK)
533 		flags |= MSG_DONTWAIT;
534 	if (flags & MSG_WAITALL)
535 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
536 
537 	kmsg->msg.msg_control_user = sr->msg_control;
538 
539 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
540 
541 	if (ret < min_ret) {
542 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
543 			return -EAGAIN;
544 		if (ret > 0 && io_net_retry(sock, flags)) {
545 			kmsg->msg.msg_controllen = 0;
546 			kmsg->msg.msg_control = NULL;
547 			sr->done_io += ret;
548 			req->flags |= REQ_F_BL_NO_RECYCLE;
549 			return -EAGAIN;
550 		}
551 		if (ret == -ERESTARTSYS)
552 			ret = -EINTR;
553 		req_set_fail(req);
554 	}
555 	io_req_msg_cleanup(req, issue_flags);
556 	if (ret >= 0)
557 		ret += sr->done_io;
558 	else if (sr->done_io)
559 		ret = sr->done_io;
560 	io_req_set_res(req, ret, 0);
561 	return IOU_OK;
562 }
563 
io_send_select_buffer(struct io_kiocb * req,unsigned int issue_flags,struct io_async_msghdr * kmsg)564 static int io_send_select_buffer(struct io_kiocb *req, unsigned int issue_flags,
565 				 struct io_async_msghdr *kmsg)
566 {
567 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
568 
569 	int ret;
570 	struct buf_sel_arg arg = {
571 		.iovs = &kmsg->fast_iov,
572 		.max_len = min_not_zero(sr->len, INT_MAX),
573 		.nr_iovs = 1,
574 	};
575 
576 	if (kmsg->vec.iovec) {
577 		arg.nr_iovs = kmsg->vec.nr;
578 		arg.iovs = kmsg->vec.iovec;
579 		arg.mode = KBUF_MODE_FREE;
580 	}
581 
582 	if (!(sr->flags & IORING_RECVSEND_BUNDLE))
583 		arg.nr_iovs = 1;
584 	else
585 		arg.mode |= KBUF_MODE_EXPAND;
586 
587 	ret = io_buffers_select(req, &arg, issue_flags);
588 	if (unlikely(ret < 0))
589 		return ret;
590 
591 	if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->vec.iovec) {
592 		kmsg->vec.nr = ret;
593 		kmsg->vec.iovec = arg.iovs;
594 		req->flags |= REQ_F_NEED_CLEANUP;
595 	}
596 	sr->len = arg.out_len;
597 
598 	if (ret == 1) {
599 		sr->buf = arg.iovs[0].iov_base;
600 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
601 					&kmsg->msg.msg_iter);
602 		if (unlikely(ret))
603 			return ret;
604 	} else {
605 		iov_iter_init(&kmsg->msg.msg_iter, ITER_SOURCE,
606 				arg.iovs, ret, arg.out_len);
607 	}
608 
609 	return 0;
610 }
611 
io_send(struct io_kiocb * req,unsigned int issue_flags)612 int io_send(struct io_kiocb *req, unsigned int issue_flags)
613 {
614 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
615 	struct io_async_msghdr *kmsg = req->async_data;
616 	struct socket *sock;
617 	unsigned flags;
618 	int min_ret = 0;
619 	int ret;
620 
621 	sock = sock_from_file(req->file);
622 	if (unlikely(!sock))
623 		return -ENOTSOCK;
624 
625 	if (!(req->flags & REQ_F_POLLED) &&
626 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
627 		return -EAGAIN;
628 
629 	flags = sr->msg_flags;
630 	if (issue_flags & IO_URING_F_NONBLOCK)
631 		flags |= MSG_DONTWAIT;
632 
633 retry_bundle:
634 	if (io_do_buffer_select(req)) {
635 		ret = io_send_select_buffer(req, issue_flags, kmsg);
636 		if (ret)
637 			return ret;
638 	}
639 
640 	/*
641 	 * If MSG_WAITALL is set, or this is a bundle send, then we need
642 	 * the full amount. If just bundle is set, if we do a short send
643 	 * then we complete the bundle sequence rather than continue on.
644 	 */
645 	if (flags & MSG_WAITALL || sr->flags & IORING_RECVSEND_BUNDLE)
646 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
647 
648 	flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
649 	kmsg->msg.msg_flags = flags;
650 	ret = sock_sendmsg(sock, &kmsg->msg);
651 	if (ret < min_ret) {
652 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
653 			return -EAGAIN;
654 
655 		if (ret > 0 && io_net_retry(sock, flags)) {
656 			sr->len -= ret;
657 			sr->buf += ret;
658 			sr->done_io += ret;
659 			req->flags |= REQ_F_BL_NO_RECYCLE;
660 			return -EAGAIN;
661 		}
662 		if (ret == -ERESTARTSYS)
663 			ret = -EINTR;
664 		req_set_fail(req);
665 	}
666 	if (ret >= 0)
667 		ret += sr->done_io;
668 	else if (sr->done_io)
669 		ret = sr->done_io;
670 
671 	if (!io_send_finish(req, &ret, kmsg, issue_flags))
672 		goto retry_bundle;
673 
674 	io_req_msg_cleanup(req, issue_flags);
675 	return ret;
676 }
677 
io_recvmsg_mshot_prep(struct io_kiocb * req,struct io_async_msghdr * iomsg,int namelen,size_t controllen)678 static int io_recvmsg_mshot_prep(struct io_kiocb *req,
679 				 struct io_async_msghdr *iomsg,
680 				 int namelen, size_t controllen)
681 {
682 	if ((req->flags & (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) ==
683 			  (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) {
684 		int hdr;
685 
686 		if (unlikely(namelen < 0))
687 			return -EOVERFLOW;
688 		if (check_add_overflow(sizeof(struct io_uring_recvmsg_out),
689 					namelen, &hdr))
690 			return -EOVERFLOW;
691 		if (check_add_overflow(hdr, controllen, &hdr))
692 			return -EOVERFLOW;
693 
694 		iomsg->namelen = namelen;
695 		iomsg->controllen = controllen;
696 		return 0;
697 	}
698 
699 	return 0;
700 }
701 
io_recvmsg_copy_hdr(struct io_kiocb * req,struct io_async_msghdr * iomsg)702 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
703 			       struct io_async_msghdr *iomsg)
704 {
705 	struct user_msghdr msg;
706 	int ret;
707 
708 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_DEST, &iomsg->uaddr);
709 	if (unlikely(ret))
710 		return ret;
711 
712 	if (!(req->flags & REQ_F_BUFFER_SELECT)) {
713 		ret = io_net_import_vec(req, iomsg, msg.msg_iov, msg.msg_iovlen,
714 					ITER_DEST);
715 		if (unlikely(ret))
716 			return ret;
717 	}
718 	return io_recvmsg_mshot_prep(req, iomsg, msg.msg_namelen,
719 					msg.msg_controllen);
720 }
721 
io_recvmsg_prep_setup(struct io_kiocb * req)722 static int io_recvmsg_prep_setup(struct io_kiocb *req)
723 {
724 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
725 	struct io_async_msghdr *kmsg;
726 	int ret;
727 
728 	kmsg = io_msg_alloc_async(req);
729 	if (unlikely(!kmsg))
730 		return -ENOMEM;
731 
732 	if (req->opcode == IORING_OP_RECV) {
733 		kmsg->msg.msg_name = NULL;
734 		kmsg->msg.msg_namelen = 0;
735 		kmsg->msg.msg_inq = 0;
736 		kmsg->msg.msg_control = NULL;
737 		kmsg->msg.msg_get_inq = 1;
738 		kmsg->msg.msg_controllen = 0;
739 		kmsg->msg.msg_iocb = NULL;
740 		kmsg->msg.msg_ubuf = NULL;
741 
742 		if (!io_do_buffer_select(req)) {
743 			ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
744 					  &kmsg->msg.msg_iter);
745 			if (unlikely(ret))
746 				return ret;
747 		}
748 		return 0;
749 	}
750 
751 	return io_recvmsg_copy_hdr(req, kmsg);
752 }
753 
754 #define RECVMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT | \
755 			IORING_RECVSEND_BUNDLE)
756 
io_recvmsg_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)757 int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
758 {
759 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
760 
761 	sr->done_io = 0;
762 	sr->retry = false;
763 
764 	if (unlikely(sqe->file_index || sqe->addr2))
765 		return -EINVAL;
766 
767 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
768 	sr->len = READ_ONCE(sqe->len);
769 	sr->flags = READ_ONCE(sqe->ioprio);
770 	if (sr->flags & ~RECVMSG_FLAGS)
771 		return -EINVAL;
772 	sr->msg_flags = READ_ONCE(sqe->msg_flags);
773 	if (sr->msg_flags & MSG_DONTWAIT)
774 		req->flags |= REQ_F_NOWAIT;
775 	if (sr->msg_flags & MSG_ERRQUEUE)
776 		req->flags |= REQ_F_CLEAR_POLLIN;
777 	if (req->flags & REQ_F_BUFFER_SELECT) {
778 		/*
779 		 * Store the buffer group for this multishot receive separately,
780 		 * as if we end up doing an io-wq based issue that selects a
781 		 * buffer, it has to be committed immediately and that will
782 		 * clear ->buf_list. This means we lose the link to the buffer
783 		 * list, and the eventual buffer put on completion then cannot
784 		 * restore it.
785 		 */
786 		sr->buf_group = req->buf_index;
787 		req->buf_list = NULL;
788 	}
789 	if (sr->flags & IORING_RECV_MULTISHOT) {
790 		if (!(req->flags & REQ_F_BUFFER_SELECT))
791 			return -EINVAL;
792 		if (sr->msg_flags & MSG_WAITALL)
793 			return -EINVAL;
794 		if (req->opcode == IORING_OP_RECV && sr->len)
795 			return -EINVAL;
796 		req->flags |= REQ_F_APOLL_MULTISHOT;
797 	}
798 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
799 		if (req->opcode == IORING_OP_RECVMSG)
800 			return -EINVAL;
801 	}
802 
803 	if (io_is_compat(req->ctx))
804 		sr->msg_flags |= MSG_CMSG_COMPAT;
805 
806 	sr->nr_multishot_loops = 0;
807 	return io_recvmsg_prep_setup(req);
808 }
809 
810 /* bits to clear in old and inherit in new cflags on bundle retry */
811 #define CQE_F_MASK	(IORING_CQE_F_SOCK_NONEMPTY|IORING_CQE_F_MORE)
812 
813 /*
814  * Finishes io_recv and io_recvmsg.
815  *
816  * Returns true if it is actually finished, or false if it should run
817  * again (for multishot).
818  */
io_recv_finish(struct io_kiocb * req,int * ret,struct io_async_msghdr * kmsg,bool mshot_finished,unsigned issue_flags)819 static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
820 				  struct io_async_msghdr *kmsg,
821 				  bool mshot_finished, unsigned issue_flags)
822 {
823 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
824 	unsigned int cflags = 0;
825 
826 	if (kmsg->msg.msg_inq > 0)
827 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
828 
829 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
830 		size_t this_ret = *ret - sr->done_io;
831 
832 		cflags |= io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, this_ret),
833 				      issue_flags);
834 		if (sr->retry)
835 			cflags = req->cqe.flags | (cflags & CQE_F_MASK);
836 		/* bundle with no more immediate buffers, we're done */
837 		if (req->flags & REQ_F_BL_EMPTY)
838 			goto finish;
839 		/*
840 		 * If more is available AND it was a full transfer, retry and
841 		 * append to this one
842 		 */
843 		if (!sr->retry && kmsg->msg.msg_inq > 0 && this_ret > 0 &&
844 		    !iov_iter_count(&kmsg->msg.msg_iter)) {
845 			req->cqe.flags = cflags & ~CQE_F_MASK;
846 			sr->len = kmsg->msg.msg_inq;
847 			sr->done_io += this_ret;
848 			sr->retry = true;
849 			return false;
850 		}
851 	} else {
852 		cflags |= io_put_kbuf(req, *ret, issue_flags);
853 	}
854 
855 	/*
856 	 * Fill CQE for this receive and see if we should keep trying to
857 	 * receive from this socket.
858 	 */
859 	if ((req->flags & REQ_F_APOLL_MULTISHOT) && !mshot_finished &&
860 	    io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
861 		*ret = IOU_RETRY;
862 		io_mshot_prep_retry(req, kmsg);
863 		/* Known not-empty or unknown state, retry */
864 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || kmsg->msg.msg_inq < 0) {
865 			if (sr->nr_multishot_loops++ < MULTISHOT_MAX_RETRY)
866 				return false;
867 			/* mshot retries exceeded, force a requeue */
868 			sr->nr_multishot_loops = 0;
869 			if (issue_flags & IO_URING_F_MULTISHOT)
870 				*ret = IOU_REQUEUE;
871 		}
872 		return true;
873 	}
874 
875 	/* Finish the request / stop multishot. */
876 finish:
877 	io_req_set_res(req, *ret, cflags);
878 	*ret = IOU_COMPLETE;
879 	io_req_msg_cleanup(req, issue_flags);
880 	return true;
881 }
882 
io_recvmsg_prep_multishot(struct io_async_msghdr * kmsg,struct io_sr_msg * sr,void __user ** buf,size_t * len)883 static int io_recvmsg_prep_multishot(struct io_async_msghdr *kmsg,
884 				     struct io_sr_msg *sr, void __user **buf,
885 				     size_t *len)
886 {
887 	unsigned long ubuf = (unsigned long) *buf;
888 	unsigned long hdr;
889 
890 	hdr = sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
891 		kmsg->controllen;
892 	if (*len < hdr)
893 		return -EFAULT;
894 
895 	if (kmsg->controllen) {
896 		unsigned long control = ubuf + hdr - kmsg->controllen;
897 
898 		kmsg->msg.msg_control_user = (void __user *) control;
899 		kmsg->msg.msg_controllen = kmsg->controllen;
900 	}
901 
902 	sr->buf = *buf; /* stash for later copy */
903 	*buf = (void __user *) (ubuf + hdr);
904 	kmsg->payloadlen = *len = *len - hdr;
905 	return 0;
906 }
907 
908 struct io_recvmsg_multishot_hdr {
909 	struct io_uring_recvmsg_out msg;
910 	struct sockaddr_storage addr;
911 };
912 
io_recvmsg_multishot(struct socket * sock,struct io_sr_msg * io,struct io_async_msghdr * kmsg,unsigned int flags,bool * finished)913 static int io_recvmsg_multishot(struct socket *sock, struct io_sr_msg *io,
914 				struct io_async_msghdr *kmsg,
915 				unsigned int flags, bool *finished)
916 {
917 	int err;
918 	int copy_len;
919 	struct io_recvmsg_multishot_hdr hdr;
920 
921 	if (kmsg->namelen)
922 		kmsg->msg.msg_name = &hdr.addr;
923 	kmsg->msg.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
924 	kmsg->msg.msg_namelen = 0;
925 
926 	if (sock->file->f_flags & O_NONBLOCK)
927 		flags |= MSG_DONTWAIT;
928 
929 	err = sock_recvmsg(sock, &kmsg->msg, flags);
930 	*finished = err <= 0;
931 	if (err < 0)
932 		return err;
933 
934 	hdr.msg = (struct io_uring_recvmsg_out) {
935 		.controllen = kmsg->controllen - kmsg->msg.msg_controllen,
936 		.flags = kmsg->msg.msg_flags & ~MSG_CMSG_COMPAT
937 	};
938 
939 	hdr.msg.payloadlen = err;
940 	if (err > kmsg->payloadlen)
941 		err = kmsg->payloadlen;
942 
943 	copy_len = sizeof(struct io_uring_recvmsg_out);
944 	if (kmsg->msg.msg_namelen > kmsg->namelen)
945 		copy_len += kmsg->namelen;
946 	else
947 		copy_len += kmsg->msg.msg_namelen;
948 
949 	/*
950 	 *      "fromlen shall refer to the value before truncation.."
951 	 *                      1003.1g
952 	 */
953 	hdr.msg.namelen = kmsg->msg.msg_namelen;
954 
955 	/* ensure that there is no gap between hdr and sockaddr_storage */
956 	BUILD_BUG_ON(offsetof(struct io_recvmsg_multishot_hdr, addr) !=
957 		     sizeof(struct io_uring_recvmsg_out));
958 	if (copy_to_user(io->buf, &hdr, copy_len)) {
959 		*finished = true;
960 		return -EFAULT;
961 	}
962 
963 	return sizeof(struct io_uring_recvmsg_out) + kmsg->namelen +
964 			kmsg->controllen + err;
965 }
966 
io_recvmsg(struct io_kiocb * req,unsigned int issue_flags)967 int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
968 {
969 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
970 	struct io_async_msghdr *kmsg = req->async_data;
971 	struct socket *sock;
972 	unsigned flags;
973 	int ret, min_ret = 0;
974 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
975 	bool mshot_finished = true;
976 
977 	sock = sock_from_file(req->file);
978 	if (unlikely(!sock))
979 		return -ENOTSOCK;
980 
981 	if (!(req->flags & REQ_F_POLLED) &&
982 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
983 		return -EAGAIN;
984 
985 	flags = sr->msg_flags;
986 	if (force_nonblock)
987 		flags |= MSG_DONTWAIT;
988 
989 retry_multishot:
990 	if (io_do_buffer_select(req)) {
991 		void __user *buf;
992 		size_t len = sr->len;
993 
994 		buf = io_buffer_select(req, &len, issue_flags);
995 		if (!buf)
996 			return -ENOBUFS;
997 
998 		if (req->flags & REQ_F_APOLL_MULTISHOT) {
999 			ret = io_recvmsg_prep_multishot(kmsg, sr, &buf, &len);
1000 			if (ret) {
1001 				io_kbuf_recycle(req, issue_flags);
1002 				return ret;
1003 			}
1004 		}
1005 
1006 		iov_iter_ubuf(&kmsg->msg.msg_iter, ITER_DEST, buf, len);
1007 	}
1008 
1009 	kmsg->msg.msg_get_inq = 1;
1010 	kmsg->msg.msg_inq = -1;
1011 	if (req->flags & REQ_F_APOLL_MULTISHOT) {
1012 		ret = io_recvmsg_multishot(sock, sr, kmsg, flags,
1013 					   &mshot_finished);
1014 	} else {
1015 		/* disable partial retry for recvmsg with cmsg attached */
1016 		if (flags & MSG_WAITALL && !kmsg->msg.msg_controllen)
1017 			min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1018 
1019 		ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg,
1020 					 kmsg->uaddr, flags);
1021 	}
1022 
1023 	if (ret < min_ret) {
1024 		if (ret == -EAGAIN && force_nonblock) {
1025 			if (issue_flags & IO_URING_F_MULTISHOT)
1026 				io_kbuf_recycle(req, issue_flags);
1027 
1028 			return IOU_RETRY;
1029 		}
1030 		if (ret > 0 && io_net_retry(sock, flags)) {
1031 			sr->done_io += ret;
1032 			req->flags |= REQ_F_BL_NO_RECYCLE;
1033 			return IOU_RETRY;
1034 		}
1035 		if (ret == -ERESTARTSYS)
1036 			ret = -EINTR;
1037 		req_set_fail(req);
1038 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1039 		req_set_fail(req);
1040 	}
1041 
1042 	if (ret > 0)
1043 		ret += sr->done_io;
1044 	else if (sr->done_io)
1045 		ret = sr->done_io;
1046 	else
1047 		io_kbuf_recycle(req, issue_flags);
1048 
1049 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1050 		goto retry_multishot;
1051 
1052 	return ret;
1053 }
1054 
io_recv_buf_select(struct io_kiocb * req,struct io_async_msghdr * kmsg,size_t * len,unsigned int issue_flags)1055 static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg,
1056 			      size_t *len, unsigned int issue_flags)
1057 {
1058 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1059 	int ret;
1060 
1061 	/*
1062 	 * If the ring isn't locked, then don't use the peek interface
1063 	 * to grab multiple buffers as we will lock/unlock between
1064 	 * this selection and posting the buffers.
1065 	 */
1066 	if (!(issue_flags & IO_URING_F_UNLOCKED) &&
1067 	    sr->flags & IORING_RECVSEND_BUNDLE) {
1068 		struct buf_sel_arg arg = {
1069 			.iovs = &kmsg->fast_iov,
1070 			.nr_iovs = 1,
1071 			.mode = KBUF_MODE_EXPAND,
1072 		};
1073 
1074 		if (kmsg->vec.iovec) {
1075 			arg.nr_iovs = kmsg->vec.nr;
1076 			arg.iovs = kmsg->vec.iovec;
1077 			arg.mode |= KBUF_MODE_FREE;
1078 		}
1079 
1080 		if (kmsg->msg.msg_inq > 0)
1081 			arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq);
1082 
1083 		ret = io_buffers_peek(req, &arg);
1084 		if (unlikely(ret < 0))
1085 			return ret;
1086 
1087 		/* special case 1 vec, can be a fast path */
1088 		if (ret == 1) {
1089 			sr->buf = arg.iovs[0].iov_base;
1090 			sr->len = arg.iovs[0].iov_len;
1091 			goto map_ubuf;
1092 		}
1093 		iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, arg.iovs, ret,
1094 				arg.out_len);
1095 		if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->vec.iovec) {
1096 			kmsg->vec.nr = ret;
1097 			kmsg->vec.iovec = arg.iovs;
1098 			req->flags |= REQ_F_NEED_CLEANUP;
1099 		}
1100 	} else {
1101 		void __user *buf;
1102 
1103 		*len = sr->len;
1104 		buf = io_buffer_select(req, len, issue_flags);
1105 		if (!buf)
1106 			return -ENOBUFS;
1107 		sr->buf = buf;
1108 		sr->len = *len;
1109 map_ubuf:
1110 		ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
1111 				  &kmsg->msg.msg_iter);
1112 		if (unlikely(ret))
1113 			return ret;
1114 	}
1115 
1116 	return 0;
1117 }
1118 
io_recv(struct io_kiocb * req,unsigned int issue_flags)1119 int io_recv(struct io_kiocb *req, unsigned int issue_flags)
1120 {
1121 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1122 	struct io_async_msghdr *kmsg = req->async_data;
1123 	struct socket *sock;
1124 	unsigned flags;
1125 	int ret, min_ret = 0;
1126 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1127 	size_t len = sr->len;
1128 	bool mshot_finished;
1129 
1130 	if (!(req->flags & REQ_F_POLLED) &&
1131 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1132 		return -EAGAIN;
1133 
1134 	sock = sock_from_file(req->file);
1135 	if (unlikely(!sock))
1136 		return -ENOTSOCK;
1137 
1138 	flags = sr->msg_flags;
1139 	if (force_nonblock)
1140 		flags |= MSG_DONTWAIT;
1141 
1142 retry_multishot:
1143 	if (io_do_buffer_select(req)) {
1144 		ret = io_recv_buf_select(req, kmsg, &len, issue_flags);
1145 		if (unlikely(ret)) {
1146 			kmsg->msg.msg_inq = -1;
1147 			goto out_free;
1148 		}
1149 		sr->buf = NULL;
1150 	}
1151 
1152 	kmsg->msg.msg_flags = 0;
1153 	kmsg->msg.msg_inq = -1;
1154 
1155 	if (flags & MSG_WAITALL)
1156 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1157 
1158 	ret = sock_recvmsg(sock, &kmsg->msg, flags);
1159 	if (ret < min_ret) {
1160 		if (ret == -EAGAIN && force_nonblock) {
1161 			if (issue_flags & IO_URING_F_MULTISHOT)
1162 				io_kbuf_recycle(req, issue_flags);
1163 
1164 			return IOU_RETRY;
1165 		}
1166 		if (ret > 0 && io_net_retry(sock, flags)) {
1167 			sr->len -= ret;
1168 			sr->buf += ret;
1169 			sr->done_io += ret;
1170 			req->flags |= REQ_F_BL_NO_RECYCLE;
1171 			return -EAGAIN;
1172 		}
1173 		if (ret == -ERESTARTSYS)
1174 			ret = -EINTR;
1175 		req_set_fail(req);
1176 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1177 out_free:
1178 		req_set_fail(req);
1179 	}
1180 
1181 	mshot_finished = ret <= 0;
1182 	if (ret > 0)
1183 		ret += sr->done_io;
1184 	else if (sr->done_io)
1185 		ret = sr->done_io;
1186 	else
1187 		io_kbuf_recycle(req, issue_flags);
1188 
1189 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1190 		goto retry_multishot;
1191 
1192 	return ret;
1193 }
1194 
io_recvzc_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1195 int io_recvzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1196 {
1197 	struct io_recvzc *zc = io_kiocb_to_cmd(req, struct io_recvzc);
1198 	unsigned ifq_idx;
1199 
1200 	if (unlikely(sqe->file_index || sqe->addr2 || sqe->addr ||
1201 		     sqe->addr3))
1202 		return -EINVAL;
1203 
1204 	ifq_idx = READ_ONCE(sqe->zcrx_ifq_idx);
1205 	if (ifq_idx != 0)
1206 		return -EINVAL;
1207 	zc->ifq = req->ctx->ifq;
1208 	if (!zc->ifq)
1209 		return -EINVAL;
1210 	zc->len = READ_ONCE(sqe->len);
1211 	zc->flags = READ_ONCE(sqe->ioprio);
1212 	zc->msg_flags = READ_ONCE(sqe->msg_flags);
1213 	if (zc->msg_flags)
1214 		return -EINVAL;
1215 	if (zc->flags & ~(IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT))
1216 		return -EINVAL;
1217 	/* multishot required */
1218 	if (!(zc->flags & IORING_RECV_MULTISHOT))
1219 		return -EINVAL;
1220 	/* All data completions are posted as aux CQEs. */
1221 	req->flags |= REQ_F_APOLL_MULTISHOT;
1222 
1223 	return 0;
1224 }
1225 
io_recvzc(struct io_kiocb * req,unsigned int issue_flags)1226 int io_recvzc(struct io_kiocb *req, unsigned int issue_flags)
1227 {
1228 	struct io_recvzc *zc = io_kiocb_to_cmd(req, struct io_recvzc);
1229 	struct socket *sock;
1230 	unsigned int len;
1231 	int ret;
1232 
1233 	if (!(req->flags & REQ_F_POLLED) &&
1234 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1235 		return -EAGAIN;
1236 
1237 	sock = sock_from_file(req->file);
1238 	if (unlikely(!sock))
1239 		return -ENOTSOCK;
1240 
1241 	len = zc->len;
1242 	ret = io_zcrx_recv(req, zc->ifq, sock, zc->msg_flags | MSG_DONTWAIT,
1243 			   issue_flags, &zc->len);
1244 	if (len && zc->len == 0) {
1245 		io_req_set_res(req, 0, 0);
1246 
1247 		return IOU_COMPLETE;
1248 	}
1249 	if (unlikely(ret <= 0) && ret != -EAGAIN) {
1250 		if (ret == -ERESTARTSYS)
1251 			ret = -EINTR;
1252 		if (ret == IOU_REQUEUE)
1253 			return IOU_REQUEUE;
1254 
1255 		req_set_fail(req);
1256 		io_req_set_res(req, ret, 0);
1257 		return IOU_COMPLETE;
1258 	}
1259 	return IOU_RETRY;
1260 }
1261 
io_send_zc_cleanup(struct io_kiocb * req)1262 void io_send_zc_cleanup(struct io_kiocb *req)
1263 {
1264 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1265 	struct io_async_msghdr *io = req->async_data;
1266 
1267 	if (req_has_async_data(req))
1268 		io_netmsg_iovec_free(io);
1269 	if (zc->notif) {
1270 		io_notif_flush(zc->notif);
1271 		zc->notif = NULL;
1272 	}
1273 }
1274 
1275 #define IO_ZC_FLAGS_COMMON (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_FIXED_BUF)
1276 #define IO_ZC_FLAGS_VALID  (IO_ZC_FLAGS_COMMON | IORING_SEND_ZC_REPORT_USAGE)
1277 
io_send_zc_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1278 int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1279 {
1280 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1281 	struct io_ring_ctx *ctx = req->ctx;
1282 	struct io_async_msghdr *iomsg;
1283 	struct io_kiocb *notif;
1284 	int ret;
1285 
1286 	zc->done_io = 0;
1287 	zc->retry = false;
1288 
1289 	if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3)))
1290 		return -EINVAL;
1291 	/* we don't support IOSQE_CQE_SKIP_SUCCESS just yet */
1292 	if (req->flags & REQ_F_CQE_SKIP)
1293 		return -EINVAL;
1294 
1295 	notif = zc->notif = io_alloc_notif(ctx);
1296 	if (!notif)
1297 		return -ENOMEM;
1298 	notif->cqe.user_data = req->cqe.user_data;
1299 	notif->cqe.res = 0;
1300 	notif->cqe.flags = IORING_CQE_F_NOTIF;
1301 	req->flags |= REQ_F_NEED_CLEANUP | REQ_F_POLL_NO_LAZY;
1302 
1303 	zc->flags = READ_ONCE(sqe->ioprio);
1304 	if (unlikely(zc->flags & ~IO_ZC_FLAGS_COMMON)) {
1305 		if (zc->flags & ~IO_ZC_FLAGS_VALID)
1306 			return -EINVAL;
1307 		if (zc->flags & IORING_SEND_ZC_REPORT_USAGE) {
1308 			struct io_notif_data *nd = io_notif_to_data(notif);
1309 
1310 			nd->zc_report = true;
1311 			nd->zc_used = false;
1312 			nd->zc_copied = false;
1313 		}
1314 	}
1315 
1316 	zc->len = READ_ONCE(sqe->len);
1317 	zc->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL | MSG_ZEROCOPY;
1318 	req->buf_index = READ_ONCE(sqe->buf_index);
1319 	if (zc->msg_flags & MSG_DONTWAIT)
1320 		req->flags |= REQ_F_NOWAIT;
1321 
1322 	if (io_is_compat(req->ctx))
1323 		zc->msg_flags |= MSG_CMSG_COMPAT;
1324 
1325 	iomsg = io_msg_alloc_async(req);
1326 	if (unlikely(!iomsg))
1327 		return -ENOMEM;
1328 
1329 	if (req->opcode == IORING_OP_SEND_ZC) {
1330 		if (zc->flags & IORING_RECVSEND_FIXED_BUF)
1331 			req->flags |= REQ_F_IMPORT_BUFFER;
1332 		ret = io_send_setup(req, sqe);
1333 	} else {
1334 		if (unlikely(sqe->addr2 || sqe->file_index))
1335 			return -EINVAL;
1336 		ret = io_sendmsg_setup(req, sqe);
1337 	}
1338 	if (unlikely(ret))
1339 		return ret;
1340 
1341 	if (!(zc->flags & IORING_RECVSEND_FIXED_BUF)) {
1342 		iomsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1343 		return io_notif_account_mem(zc->notif, iomsg->msg.msg_iter.count);
1344 	}
1345 	iomsg->msg.sg_from_iter = io_sg_from_iter;
1346 	return 0;
1347 }
1348 
io_sg_from_iter_iovec(struct sk_buff * skb,struct iov_iter * from,size_t length)1349 static int io_sg_from_iter_iovec(struct sk_buff *skb,
1350 				 struct iov_iter *from, size_t length)
1351 {
1352 	skb_zcopy_downgrade_managed(skb);
1353 	return zerocopy_fill_skb_from_iter(skb, from, length);
1354 }
1355 
io_sg_from_iter(struct sk_buff * skb,struct iov_iter * from,size_t length)1356 static int io_sg_from_iter(struct sk_buff *skb,
1357 			   struct iov_iter *from, size_t length)
1358 {
1359 	struct skb_shared_info *shinfo = skb_shinfo(skb);
1360 	int frag = shinfo->nr_frags;
1361 	int ret = 0;
1362 	struct bvec_iter bi;
1363 	ssize_t copied = 0;
1364 	unsigned long truesize = 0;
1365 
1366 	if (!frag)
1367 		shinfo->flags |= SKBFL_MANAGED_FRAG_REFS;
1368 	else if (unlikely(!skb_zcopy_managed(skb)))
1369 		return zerocopy_fill_skb_from_iter(skb, from, length);
1370 
1371 	bi.bi_size = min(from->count, length);
1372 	bi.bi_bvec_done = from->iov_offset;
1373 	bi.bi_idx = 0;
1374 
1375 	while (bi.bi_size && frag < MAX_SKB_FRAGS) {
1376 		struct bio_vec v = mp_bvec_iter_bvec(from->bvec, bi);
1377 
1378 		copied += v.bv_len;
1379 		truesize += PAGE_ALIGN(v.bv_len + v.bv_offset);
1380 		__skb_fill_page_desc_noacc(shinfo, frag++, v.bv_page,
1381 					   v.bv_offset, v.bv_len);
1382 		bvec_iter_advance_single(from->bvec, &bi, v.bv_len);
1383 	}
1384 	if (bi.bi_size)
1385 		ret = -EMSGSIZE;
1386 
1387 	shinfo->nr_frags = frag;
1388 	from->bvec += bi.bi_idx;
1389 	from->nr_segs -= bi.bi_idx;
1390 	from->count -= copied;
1391 	from->iov_offset = bi.bi_bvec_done;
1392 
1393 	skb->data_len += copied;
1394 	skb->len += copied;
1395 	skb->truesize += truesize;
1396 	return ret;
1397 }
1398 
io_send_zc_import(struct io_kiocb * req,unsigned int issue_flags)1399 static int io_send_zc_import(struct io_kiocb *req, unsigned int issue_flags)
1400 {
1401 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1402 	struct io_async_msghdr *kmsg = req->async_data;
1403 
1404 	WARN_ON_ONCE(!(sr->flags & IORING_RECVSEND_FIXED_BUF));
1405 
1406 	sr->notif->buf_index = req->buf_index;
1407 	return io_import_reg_buf(sr->notif, &kmsg->msg.msg_iter,
1408 				(u64)(uintptr_t)sr->buf, sr->len,
1409 				ITER_SOURCE, issue_flags);
1410 }
1411 
io_send_zc(struct io_kiocb * req,unsigned int issue_flags)1412 int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
1413 {
1414 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1415 	struct io_async_msghdr *kmsg = req->async_data;
1416 	struct socket *sock;
1417 	unsigned msg_flags;
1418 	int ret, min_ret = 0;
1419 
1420 	sock = sock_from_file(req->file);
1421 	if (unlikely(!sock))
1422 		return -ENOTSOCK;
1423 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1424 		return -EOPNOTSUPP;
1425 
1426 	if (!(req->flags & REQ_F_POLLED) &&
1427 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1428 		return -EAGAIN;
1429 
1430 	if (req->flags & REQ_F_IMPORT_BUFFER) {
1431 		req->flags &= ~REQ_F_IMPORT_BUFFER;
1432 		ret = io_send_zc_import(req, issue_flags);
1433 		if (unlikely(ret))
1434 			return ret;
1435 	}
1436 
1437 	msg_flags = zc->msg_flags;
1438 	if (issue_flags & IO_URING_F_NONBLOCK)
1439 		msg_flags |= MSG_DONTWAIT;
1440 	if (msg_flags & MSG_WAITALL)
1441 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1442 	msg_flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
1443 
1444 	kmsg->msg.msg_flags = msg_flags;
1445 	kmsg->msg.msg_ubuf = &io_notif_to_data(zc->notif)->uarg;
1446 	ret = sock_sendmsg(sock, &kmsg->msg);
1447 
1448 	if (unlikely(ret < min_ret)) {
1449 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1450 			return -EAGAIN;
1451 
1452 		if (ret > 0 && io_net_retry(sock, kmsg->msg.msg_flags)) {
1453 			zc->len -= ret;
1454 			zc->buf += ret;
1455 			zc->done_io += ret;
1456 			req->flags |= REQ_F_BL_NO_RECYCLE;
1457 			return -EAGAIN;
1458 		}
1459 		if (ret == -ERESTARTSYS)
1460 			ret = -EINTR;
1461 		req_set_fail(req);
1462 	}
1463 
1464 	if (ret >= 0)
1465 		ret += zc->done_io;
1466 	else if (zc->done_io)
1467 		ret = zc->done_io;
1468 
1469 	/*
1470 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1471 	 * flushing notif to io_send_zc_cleanup()
1472 	 */
1473 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1474 		io_notif_flush(zc->notif);
1475 		zc->notif = NULL;
1476 		io_req_msg_cleanup(req, 0);
1477 	}
1478 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1479 	return IOU_OK;
1480 }
1481 
io_sendmsg_zc(struct io_kiocb * req,unsigned int issue_flags)1482 int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags)
1483 {
1484 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1485 	struct io_async_msghdr *kmsg = req->async_data;
1486 	struct socket *sock;
1487 	unsigned flags;
1488 	int ret, min_ret = 0;
1489 
1490 	if (req->flags & REQ_F_IMPORT_BUFFER) {
1491 		unsigned uvec_segs = kmsg->msg.msg_iter.nr_segs;
1492 		int ret;
1493 
1494 		ret = io_import_reg_vec(ITER_SOURCE, &kmsg->msg.msg_iter, req,
1495 					&kmsg->vec, uvec_segs, issue_flags);
1496 		if (unlikely(ret))
1497 			return ret;
1498 		req->flags &= ~REQ_F_IMPORT_BUFFER;
1499 	}
1500 
1501 	sock = sock_from_file(req->file);
1502 	if (unlikely(!sock))
1503 		return -ENOTSOCK;
1504 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1505 		return -EOPNOTSUPP;
1506 
1507 	if (!(req->flags & REQ_F_POLLED) &&
1508 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1509 		return -EAGAIN;
1510 
1511 	flags = sr->msg_flags;
1512 	if (issue_flags & IO_URING_F_NONBLOCK)
1513 		flags |= MSG_DONTWAIT;
1514 	if (flags & MSG_WAITALL)
1515 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1516 
1517 	kmsg->msg.msg_control_user = sr->msg_control;
1518 	kmsg->msg.msg_ubuf = &io_notif_to_data(sr->notif)->uarg;
1519 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
1520 
1521 	if (unlikely(ret < min_ret)) {
1522 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1523 			return -EAGAIN;
1524 
1525 		if (ret > 0 && io_net_retry(sock, flags)) {
1526 			sr->done_io += ret;
1527 			req->flags |= REQ_F_BL_NO_RECYCLE;
1528 			return -EAGAIN;
1529 		}
1530 		if (ret == -ERESTARTSYS)
1531 			ret = -EINTR;
1532 		req_set_fail(req);
1533 	}
1534 
1535 	if (ret >= 0)
1536 		ret += sr->done_io;
1537 	else if (sr->done_io)
1538 		ret = sr->done_io;
1539 
1540 	/*
1541 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1542 	 * flushing notif to io_send_zc_cleanup()
1543 	 */
1544 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1545 		io_notif_flush(sr->notif);
1546 		sr->notif = NULL;
1547 		io_req_msg_cleanup(req, 0);
1548 	}
1549 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1550 	return IOU_OK;
1551 }
1552 
io_sendrecv_fail(struct io_kiocb * req)1553 void io_sendrecv_fail(struct io_kiocb *req)
1554 {
1555 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1556 
1557 	if (sr->done_io)
1558 		req->cqe.res = sr->done_io;
1559 
1560 	if ((req->flags & REQ_F_NEED_CLEANUP) &&
1561 	    (req->opcode == IORING_OP_SEND_ZC || req->opcode == IORING_OP_SENDMSG_ZC))
1562 		req->cqe.flags |= IORING_CQE_F_MORE;
1563 }
1564 
1565 #define ACCEPT_FLAGS	(IORING_ACCEPT_MULTISHOT | IORING_ACCEPT_DONTWAIT | \
1566 			 IORING_ACCEPT_POLL_FIRST)
1567 
io_accept_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1568 int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1569 {
1570 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1571 
1572 	if (sqe->len || sqe->buf_index)
1573 		return -EINVAL;
1574 
1575 	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1576 	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
1577 	accept->flags = READ_ONCE(sqe->accept_flags);
1578 	accept->nofile = rlimit(RLIMIT_NOFILE);
1579 	accept->iou_flags = READ_ONCE(sqe->ioprio);
1580 	if (accept->iou_flags & ~ACCEPT_FLAGS)
1581 		return -EINVAL;
1582 
1583 	accept->file_slot = READ_ONCE(sqe->file_index);
1584 	if (accept->file_slot) {
1585 		if (accept->flags & SOCK_CLOEXEC)
1586 			return -EINVAL;
1587 		if (accept->iou_flags & IORING_ACCEPT_MULTISHOT &&
1588 		    accept->file_slot != IORING_FILE_INDEX_ALLOC)
1589 			return -EINVAL;
1590 	}
1591 	if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1592 		return -EINVAL;
1593 	if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
1594 		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1595 	if (accept->iou_flags & IORING_ACCEPT_MULTISHOT)
1596 		req->flags |= REQ_F_APOLL_MULTISHOT;
1597 	if (accept->iou_flags & IORING_ACCEPT_DONTWAIT)
1598 		req->flags |= REQ_F_NOWAIT;
1599 	return 0;
1600 }
1601 
io_accept(struct io_kiocb * req,unsigned int issue_flags)1602 int io_accept(struct io_kiocb *req, unsigned int issue_flags)
1603 {
1604 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1605 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1606 	bool fixed = !!accept->file_slot;
1607 	struct proto_accept_arg arg = {
1608 		.flags = force_nonblock ? O_NONBLOCK : 0,
1609 	};
1610 	struct file *file;
1611 	unsigned cflags;
1612 	int ret, fd;
1613 
1614 	if (!(req->flags & REQ_F_POLLED) &&
1615 	    accept->iou_flags & IORING_ACCEPT_POLL_FIRST)
1616 		return -EAGAIN;
1617 
1618 retry:
1619 	if (!fixed) {
1620 		fd = __get_unused_fd_flags(accept->flags, accept->nofile);
1621 		if (unlikely(fd < 0))
1622 			return fd;
1623 	}
1624 	arg.err = 0;
1625 	arg.is_empty = -1;
1626 	file = do_accept(req->file, &arg, accept->addr, accept->addr_len,
1627 			 accept->flags);
1628 	if (IS_ERR(file)) {
1629 		if (!fixed)
1630 			put_unused_fd(fd);
1631 		ret = PTR_ERR(file);
1632 		if (ret == -EAGAIN && force_nonblock &&
1633 		    !(accept->iou_flags & IORING_ACCEPT_DONTWAIT))
1634 			return IOU_RETRY;
1635 
1636 		if (ret == -ERESTARTSYS)
1637 			ret = -EINTR;
1638 	} else if (!fixed) {
1639 		fd_install(fd, file);
1640 		ret = fd;
1641 	} else {
1642 		ret = io_fixed_fd_install(req, issue_flags, file,
1643 						accept->file_slot);
1644 	}
1645 
1646 	cflags = 0;
1647 	if (!arg.is_empty)
1648 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
1649 
1650 	if (ret >= 0 && (req->flags & REQ_F_APOLL_MULTISHOT) &&
1651 	    io_req_post_cqe(req, ret, cflags | IORING_CQE_F_MORE)) {
1652 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || arg.is_empty == -1)
1653 			goto retry;
1654 		return IOU_RETRY;
1655 	}
1656 
1657 	io_req_set_res(req, ret, cflags);
1658 	if (ret < 0)
1659 		req_set_fail(req);
1660 	return IOU_COMPLETE;
1661 }
1662 
io_socket_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1663 int io_socket_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1664 {
1665 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1666 
1667 	if (sqe->addr || sqe->rw_flags || sqe->buf_index)
1668 		return -EINVAL;
1669 
1670 	sock->domain = READ_ONCE(sqe->fd);
1671 	sock->type = READ_ONCE(sqe->off);
1672 	sock->protocol = READ_ONCE(sqe->len);
1673 	sock->file_slot = READ_ONCE(sqe->file_index);
1674 	sock->nofile = rlimit(RLIMIT_NOFILE);
1675 
1676 	sock->flags = sock->type & ~SOCK_TYPE_MASK;
1677 	if (sock->file_slot && (sock->flags & SOCK_CLOEXEC))
1678 		return -EINVAL;
1679 	if (sock->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1680 		return -EINVAL;
1681 	return 0;
1682 }
1683 
io_socket(struct io_kiocb * req,unsigned int issue_flags)1684 int io_socket(struct io_kiocb *req, unsigned int issue_flags)
1685 {
1686 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1687 	bool fixed = !!sock->file_slot;
1688 	struct file *file;
1689 	int ret, fd;
1690 
1691 	if (!fixed) {
1692 		fd = __get_unused_fd_flags(sock->flags, sock->nofile);
1693 		if (unlikely(fd < 0))
1694 			return fd;
1695 	}
1696 	file = __sys_socket_file(sock->domain, sock->type, sock->protocol);
1697 	if (IS_ERR(file)) {
1698 		if (!fixed)
1699 			put_unused_fd(fd);
1700 		ret = PTR_ERR(file);
1701 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1702 			return -EAGAIN;
1703 		if (ret == -ERESTARTSYS)
1704 			ret = -EINTR;
1705 		req_set_fail(req);
1706 	} else if (!fixed) {
1707 		fd_install(fd, file);
1708 		ret = fd;
1709 	} else {
1710 		ret = io_fixed_fd_install(req, issue_flags, file,
1711 					    sock->file_slot);
1712 	}
1713 	io_req_set_res(req, ret, 0);
1714 	return IOU_OK;
1715 }
1716 
io_connect_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1717 int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1718 {
1719 	struct io_connect *conn = io_kiocb_to_cmd(req, struct io_connect);
1720 	struct io_async_msghdr *io;
1721 
1722 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1723 		return -EINVAL;
1724 
1725 	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1726 	conn->addr_len =  READ_ONCE(sqe->addr2);
1727 	conn->in_progress = conn->seen_econnaborted = false;
1728 
1729 	io = io_msg_alloc_async(req);
1730 	if (unlikely(!io))
1731 		return -ENOMEM;
1732 
1733 	return move_addr_to_kernel(conn->addr, conn->addr_len, &io->addr);
1734 }
1735 
io_connect(struct io_kiocb * req,unsigned int issue_flags)1736 int io_connect(struct io_kiocb *req, unsigned int issue_flags)
1737 {
1738 	struct io_connect *connect = io_kiocb_to_cmd(req, struct io_connect);
1739 	struct io_async_msghdr *io = req->async_data;
1740 	unsigned file_flags;
1741 	int ret;
1742 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1743 
1744 	if (unlikely(req->flags & REQ_F_FAIL)) {
1745 		ret = -ECONNRESET;
1746 		goto out;
1747 	}
1748 
1749 	file_flags = force_nonblock ? O_NONBLOCK : 0;
1750 
1751 	ret = __sys_connect_file(req->file, &io->addr, connect->addr_len,
1752 				 file_flags);
1753 	if ((ret == -EAGAIN || ret == -EINPROGRESS || ret == -ECONNABORTED)
1754 	    && force_nonblock) {
1755 		if (ret == -EINPROGRESS) {
1756 			connect->in_progress = true;
1757 		} else if (ret == -ECONNABORTED) {
1758 			if (connect->seen_econnaborted)
1759 				goto out;
1760 			connect->seen_econnaborted = true;
1761 		}
1762 		return -EAGAIN;
1763 	}
1764 	if (connect->in_progress) {
1765 		/*
1766 		 * At least bluetooth will return -EBADFD on a re-connect
1767 		 * attempt, and it's (supposedly) also valid to get -EISCONN
1768 		 * which means the previous result is good. For both of these,
1769 		 * grab the sock_error() and use that for the completion.
1770 		 */
1771 		if (ret == -EBADFD || ret == -EISCONN)
1772 			ret = sock_error(sock_from_file(req->file)->sk);
1773 	}
1774 	if (ret == -ERESTARTSYS)
1775 		ret = -EINTR;
1776 out:
1777 	if (ret < 0)
1778 		req_set_fail(req);
1779 	io_req_msg_cleanup(req, issue_flags);
1780 	io_req_set_res(req, ret, 0);
1781 	return IOU_OK;
1782 }
1783 
io_bind_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1784 int io_bind_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1785 {
1786 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1787 	struct sockaddr __user *uaddr;
1788 	struct io_async_msghdr *io;
1789 
1790 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1791 		return -EINVAL;
1792 
1793 	uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1794 	bind->addr_len =  READ_ONCE(sqe->addr2);
1795 
1796 	io = io_msg_alloc_async(req);
1797 	if (unlikely(!io))
1798 		return -ENOMEM;
1799 	return move_addr_to_kernel(uaddr, bind->addr_len, &io->addr);
1800 }
1801 
io_bind(struct io_kiocb * req,unsigned int issue_flags)1802 int io_bind(struct io_kiocb *req, unsigned int issue_flags)
1803 {
1804 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1805 	struct io_async_msghdr *io = req->async_data;
1806 	struct socket *sock;
1807 	int ret;
1808 
1809 	sock = sock_from_file(req->file);
1810 	if (unlikely(!sock))
1811 		return -ENOTSOCK;
1812 
1813 	ret = __sys_bind_socket(sock, &io->addr, bind->addr_len);
1814 	if (ret < 0)
1815 		req_set_fail(req);
1816 	io_req_set_res(req, ret, 0);
1817 	return 0;
1818 }
1819 
io_listen_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)1820 int io_listen_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1821 {
1822 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1823 
1824 	if (sqe->addr || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in || sqe->addr2)
1825 		return -EINVAL;
1826 
1827 	listen->backlog = READ_ONCE(sqe->len);
1828 	return 0;
1829 }
1830 
io_listen(struct io_kiocb * req,unsigned int issue_flags)1831 int io_listen(struct io_kiocb *req, unsigned int issue_flags)
1832 {
1833 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1834 	struct socket *sock;
1835 	int ret;
1836 
1837 	sock = sock_from_file(req->file);
1838 	if (unlikely(!sock))
1839 		return -ENOTSOCK;
1840 
1841 	ret = __sys_listen_socket(sock, listen->backlog);
1842 	if (ret < 0)
1843 		req_set_fail(req);
1844 	io_req_set_res(req, ret, 0);
1845 	return 0;
1846 }
1847 
io_netmsg_cache_free(const void * entry)1848 void io_netmsg_cache_free(const void *entry)
1849 {
1850 	struct io_async_msghdr *kmsg = (struct io_async_msghdr *) entry;
1851 
1852 	io_vec_free(&kmsg->vec);
1853 	kfree(kmsg);
1854 }
1855 #endif
1856