xref: /linux/io_uring/net.c (revision 8bc7c5e525584903ea83332e18a2118ed3b1985e)
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				addr_len;
78 	u16				buf_group;
79 	void __user			*addr;
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 int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
93 {
94 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
95 
96 	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
97 		     sqe->buf_index || sqe->splice_fd_in))
98 		return -EINVAL;
99 
100 	shutdown->how = READ_ONCE(sqe->len);
101 	req->flags |= REQ_F_FORCE_ASYNC;
102 	return 0;
103 }
104 
105 int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
106 {
107 	struct io_shutdown *shutdown = io_kiocb_to_cmd(req, struct io_shutdown);
108 	struct socket *sock;
109 	int ret;
110 
111 	WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
112 
113 	sock = sock_from_file(req->file);
114 	if (unlikely(!sock))
115 		return -ENOTSOCK;
116 
117 	ret = __sys_shutdown_sock(sock, shutdown->how);
118 	io_req_set_res(req, ret, 0);
119 	return IOU_OK;
120 }
121 
122 static bool io_net_retry(struct socket *sock, int flags)
123 {
124 	if (!(flags & MSG_WAITALL))
125 		return false;
126 	return sock->type == SOCK_STREAM || sock->type == SOCK_SEQPACKET;
127 }
128 
129 static void io_netmsg_iovec_free(struct io_async_msghdr *kmsg)
130 {
131 	if (kmsg->free_iov) {
132 		kfree(kmsg->free_iov);
133 		kmsg->free_iov_nr = 0;
134 		kmsg->free_iov = NULL;
135 	}
136 }
137 
138 static void io_netmsg_recycle(struct io_kiocb *req, unsigned int issue_flags)
139 {
140 	struct io_async_msghdr *hdr = req->async_data;
141 	struct iovec *iov;
142 
143 	/* can't recycle, ensure we free the iovec if we have one */
144 	if (unlikely(issue_flags & IO_URING_F_UNLOCKED)) {
145 		io_netmsg_iovec_free(hdr);
146 		return;
147 	}
148 
149 	/* Let normal cleanup path reap it if we fail adding to the cache */
150 	iov = hdr->free_iov;
151 	if (io_alloc_cache_put(&req->ctx->netmsg_cache, hdr)) {
152 		if (iov)
153 			kasan_mempool_poison_object(iov);
154 		req->async_data = NULL;
155 		req->flags &= ~REQ_F_ASYNC_DATA;
156 	}
157 }
158 
159 static struct io_async_msghdr *io_msg_alloc_async(struct io_kiocb *req)
160 {
161 	struct io_ring_ctx *ctx = req->ctx;
162 	struct io_async_msghdr *hdr;
163 
164 	hdr = io_alloc_cache_get(&ctx->netmsg_cache);
165 	if (hdr) {
166 		if (hdr->free_iov) {
167 			kasan_mempool_unpoison_object(hdr->free_iov,
168 				hdr->free_iov_nr * sizeof(struct iovec));
169 			req->flags |= REQ_F_NEED_CLEANUP;
170 		}
171 		req->flags |= REQ_F_ASYNC_DATA;
172 		req->async_data = hdr;
173 		return hdr;
174 	}
175 
176 	if (!io_alloc_async_data(req)) {
177 		hdr = req->async_data;
178 		hdr->free_iov_nr = 0;
179 		hdr->free_iov = NULL;
180 		return hdr;
181 	}
182 	return NULL;
183 }
184 
185 /* assign new iovec to kmsg, if we need to */
186 static int io_net_vec_assign(struct io_kiocb *req, struct io_async_msghdr *kmsg,
187 			     struct iovec *iov)
188 {
189 	if (iov) {
190 		req->flags |= REQ_F_NEED_CLEANUP;
191 		kmsg->free_iov_nr = kmsg->msg.msg_iter.nr_segs;
192 		if (kmsg->free_iov)
193 			kfree(kmsg->free_iov);
194 		kmsg->free_iov = iov;
195 	}
196 	return 0;
197 }
198 
199 static inline void io_mshot_prep_retry(struct io_kiocb *req,
200 				       struct io_async_msghdr *kmsg)
201 {
202 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
203 
204 	req->flags &= ~REQ_F_BL_EMPTY;
205 	sr->done_io = 0;
206 	sr->len = 0; /* get from the provided buffer */
207 	req->buf_index = sr->buf_group;
208 }
209 
210 #ifdef CONFIG_COMPAT
211 static int io_compat_msg_copy_hdr(struct io_kiocb *req,
212 				  struct io_async_msghdr *iomsg,
213 				  struct compat_msghdr *msg, int ddir)
214 {
215 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
216 	struct compat_iovec __user *uiov;
217 	struct iovec *iov;
218 	int ret, nr_segs;
219 
220 	if (iomsg->free_iov) {
221 		nr_segs = iomsg->free_iov_nr;
222 		iov = iomsg->free_iov;
223 	} else {
224 		iov = &iomsg->fast_iov;
225 		nr_segs = 1;
226 	}
227 
228 	if (copy_from_user(msg, sr->umsg_compat, sizeof(*msg)))
229 		return -EFAULT;
230 
231 	uiov = compat_ptr(msg->msg_iov);
232 	if (req->flags & REQ_F_BUFFER_SELECT) {
233 		compat_ssize_t clen;
234 
235 		if (msg->msg_iovlen == 0) {
236 			sr->len = iov->iov_len = 0;
237 			iov->iov_base = NULL;
238 		} else if (msg->msg_iovlen > 1) {
239 			return -EINVAL;
240 		} else {
241 			if (!access_ok(uiov, sizeof(*uiov)))
242 				return -EFAULT;
243 			if (__get_user(clen, &uiov->iov_len))
244 				return -EFAULT;
245 			if (clen < 0)
246 				return -EINVAL;
247 			sr->len = clen;
248 		}
249 
250 		return 0;
251 	}
252 
253 	ret = __import_iovec(ddir, (struct iovec __user *)uiov, msg->msg_iovlen,
254 				nr_segs, &iov, &iomsg->msg.msg_iter, true);
255 	if (unlikely(ret < 0))
256 		return ret;
257 
258 	return io_net_vec_assign(req, iomsg, iov);
259 }
260 #endif
261 
262 static int io_msg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg,
263 			   struct user_msghdr *msg, int ddir)
264 {
265 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
266 	struct iovec *iov;
267 	int ret, nr_segs;
268 
269 	if (iomsg->free_iov) {
270 		nr_segs = iomsg->free_iov_nr;
271 		iov = iomsg->free_iov;
272 	} else {
273 		iov = &iomsg->fast_iov;
274 		nr_segs = 1;
275 	}
276 
277 	if (!user_access_begin(sr->umsg, sizeof(*sr->umsg)))
278 		return -EFAULT;
279 
280 	ret = -EFAULT;
281 	unsafe_get_user(msg->msg_name, &sr->umsg->msg_name, ua_end);
282 	unsafe_get_user(msg->msg_namelen, &sr->umsg->msg_namelen, ua_end);
283 	unsafe_get_user(msg->msg_iov, &sr->umsg->msg_iov, ua_end);
284 	unsafe_get_user(msg->msg_iovlen, &sr->umsg->msg_iovlen, ua_end);
285 	unsafe_get_user(msg->msg_control, &sr->umsg->msg_control, ua_end);
286 	unsafe_get_user(msg->msg_controllen, &sr->umsg->msg_controllen, ua_end);
287 	msg->msg_flags = 0;
288 
289 	if (req->flags & REQ_F_BUFFER_SELECT) {
290 		if (msg->msg_iovlen == 0) {
291 			sr->len = iov->iov_len = 0;
292 			iov->iov_base = NULL;
293 		} else if (msg->msg_iovlen > 1) {
294 			ret = -EINVAL;
295 			goto ua_end;
296 		} else {
297 			/* we only need the length for provided buffers */
298 			if (!access_ok(&msg->msg_iov[0].iov_len, sizeof(__kernel_size_t)))
299 				goto ua_end;
300 			unsafe_get_user(iov->iov_len, &msg->msg_iov[0].iov_len,
301 					ua_end);
302 			sr->len = iov->iov_len;
303 		}
304 		ret = 0;
305 ua_end:
306 		user_access_end();
307 		return ret;
308 	}
309 
310 	user_access_end();
311 	ret = __import_iovec(ddir, msg->msg_iov, msg->msg_iovlen, nr_segs,
312 				&iov, &iomsg->msg.msg_iter, false);
313 	if (unlikely(ret < 0))
314 		return ret;
315 
316 	return io_net_vec_assign(req, iomsg, iov);
317 }
318 
319 static int io_sendmsg_copy_hdr(struct io_kiocb *req,
320 			       struct io_async_msghdr *iomsg)
321 {
322 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
323 	struct user_msghdr msg;
324 	int ret;
325 
326 	iomsg->msg.msg_name = &iomsg->addr;
327 	iomsg->msg.msg_iter.nr_segs = 0;
328 
329 #ifdef CONFIG_COMPAT
330 	if (unlikely(req->ctx->compat)) {
331 		struct compat_msghdr cmsg;
332 
333 		ret = io_compat_msg_copy_hdr(req, iomsg, &cmsg, ITER_SOURCE);
334 		if (unlikely(ret))
335 			return ret;
336 
337 		return __get_compat_msghdr(&iomsg->msg, &cmsg, NULL);
338 	}
339 #endif
340 
341 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_SOURCE);
342 	if (unlikely(ret))
343 		return ret;
344 
345 	ret = __copy_msghdr(&iomsg->msg, &msg, NULL);
346 
347 	/* save msg_control as sys_sendmsg() overwrites it */
348 	sr->msg_control = iomsg->msg.msg_control_user;
349 	return ret;
350 }
351 
352 void io_sendmsg_recvmsg_cleanup(struct io_kiocb *req)
353 {
354 	struct io_async_msghdr *io = req->async_data;
355 
356 	io_netmsg_iovec_free(io);
357 }
358 
359 static int io_send_setup(struct io_kiocb *req)
360 {
361 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
362 	struct io_async_msghdr *kmsg = req->async_data;
363 	int ret;
364 
365 	kmsg->msg.msg_name = NULL;
366 	kmsg->msg.msg_namelen = 0;
367 	kmsg->msg.msg_control = NULL;
368 	kmsg->msg.msg_controllen = 0;
369 	kmsg->msg.msg_ubuf = NULL;
370 
371 	if (sr->addr) {
372 		ret = move_addr_to_kernel(sr->addr, sr->addr_len, &kmsg->addr);
373 		if (unlikely(ret < 0))
374 			return ret;
375 		kmsg->msg.msg_name = &kmsg->addr;
376 		kmsg->msg.msg_namelen = sr->addr_len;
377 	}
378 	if (!io_do_buffer_select(req)) {
379 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len,
380 				  &kmsg->msg.msg_iter);
381 		if (unlikely(ret < 0))
382 			return ret;
383 	}
384 	return 0;
385 }
386 
387 static int io_sendmsg_prep_setup(struct io_kiocb *req, int is_msg)
388 {
389 	struct io_async_msghdr *kmsg;
390 	int ret;
391 
392 	kmsg = io_msg_alloc_async(req);
393 	if (unlikely(!kmsg))
394 		return -ENOMEM;
395 	if (!is_msg)
396 		return io_send_setup(req);
397 	ret = io_sendmsg_copy_hdr(req, kmsg);
398 	if (!ret)
399 		req->flags |= REQ_F_NEED_CLEANUP;
400 	return ret;
401 }
402 
403 #define SENDMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_BUNDLE)
404 
405 int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
406 {
407 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
408 
409 	sr->done_io = 0;
410 
411 	if (req->opcode == IORING_OP_SEND) {
412 		if (READ_ONCE(sqe->__pad3[0]))
413 			return -EINVAL;
414 		sr->addr = u64_to_user_ptr(READ_ONCE(sqe->addr2));
415 		sr->addr_len = READ_ONCE(sqe->addr_len);
416 	} else if (sqe->addr2 || sqe->file_index) {
417 		return -EINVAL;
418 	}
419 
420 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
421 	sr->len = READ_ONCE(sqe->len);
422 	sr->flags = READ_ONCE(sqe->ioprio);
423 	if (sr->flags & ~SENDMSG_FLAGS)
424 		return -EINVAL;
425 	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
426 	if (sr->msg_flags & MSG_DONTWAIT)
427 		req->flags |= REQ_F_NOWAIT;
428 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
429 		if (req->opcode == IORING_OP_SENDMSG)
430 			return -EINVAL;
431 		if (!(req->flags & REQ_F_BUFFER_SELECT))
432 			return -EINVAL;
433 		sr->msg_flags |= MSG_WAITALL;
434 		sr->buf_group = req->buf_index;
435 		req->buf_list = NULL;
436 	}
437 	if (req->flags & REQ_F_BUFFER_SELECT && sr->len)
438 		return -EINVAL;
439 
440 #ifdef CONFIG_COMPAT
441 	if (req->ctx->compat)
442 		sr->msg_flags |= MSG_CMSG_COMPAT;
443 #endif
444 	return io_sendmsg_prep_setup(req, req->opcode == IORING_OP_SENDMSG);
445 }
446 
447 static void io_req_msg_cleanup(struct io_kiocb *req,
448 			       unsigned int issue_flags)
449 {
450 	req->flags &= ~REQ_F_NEED_CLEANUP;
451 	io_netmsg_recycle(req, issue_flags);
452 }
453 
454 /*
455  * For bundle completions, we need to figure out how many segments we consumed.
456  * A bundle could be using a single ITER_UBUF if that's all we mapped, or it
457  * could be using an ITER_IOVEC. If the latter, then if we consumed all of
458  * the segments, then it's a trivial questiont o answer. If we have residual
459  * data in the iter, then loop the segments to figure out how much we
460  * transferred.
461  */
462 static int io_bundle_nbufs(struct io_async_msghdr *kmsg, int ret)
463 {
464 	struct iovec *iov;
465 	int nbufs;
466 
467 	/* no data is always zero segments, and a ubuf is always 1 segment */
468 	if (ret <= 0)
469 		return 0;
470 	if (iter_is_ubuf(&kmsg->msg.msg_iter))
471 		return 1;
472 
473 	iov = kmsg->free_iov;
474 	if (!iov)
475 		iov = &kmsg->fast_iov;
476 
477 	/* if all data was transferred, it's basic pointer math */
478 	if (!iov_iter_count(&kmsg->msg.msg_iter))
479 		return iter_iov(&kmsg->msg.msg_iter) - iov;
480 
481 	/* short transfer, count segments */
482 	nbufs = 0;
483 	do {
484 		int this_len = min_t(int, iov[nbufs].iov_len, ret);
485 
486 		nbufs++;
487 		ret -= this_len;
488 	} while (ret);
489 
490 	return nbufs;
491 }
492 
493 static inline bool io_send_finish(struct io_kiocb *req, int *ret,
494 				  struct io_async_msghdr *kmsg,
495 				  unsigned issue_flags)
496 {
497 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
498 	bool bundle_finished = *ret <= 0;
499 	unsigned int cflags;
500 
501 	if (!(sr->flags & IORING_RECVSEND_BUNDLE)) {
502 		cflags = io_put_kbuf(req, issue_flags);
503 		goto finish;
504 	}
505 
506 	cflags = io_put_kbufs(req, io_bundle_nbufs(kmsg, *ret), issue_flags);
507 
508 	if (bundle_finished || req->flags & REQ_F_BL_EMPTY)
509 		goto finish;
510 
511 	/*
512 	 * Fill CQE for this receive and see if we should keep trying to
513 	 * receive from this socket.
514 	 */
515 	if (io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
516 		io_mshot_prep_retry(req, kmsg);
517 		return false;
518 	}
519 
520 	/* Otherwise stop bundle and use the current result. */
521 finish:
522 	io_req_set_res(req, *ret, cflags);
523 	*ret = IOU_OK;
524 	return true;
525 }
526 
527 int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
528 {
529 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
530 	struct io_async_msghdr *kmsg = req->async_data;
531 	struct socket *sock;
532 	unsigned flags;
533 	int min_ret = 0;
534 	int ret;
535 
536 	sock = sock_from_file(req->file);
537 	if (unlikely(!sock))
538 		return -ENOTSOCK;
539 
540 	if (!(req->flags & REQ_F_POLLED) &&
541 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
542 		return -EAGAIN;
543 
544 	flags = sr->msg_flags;
545 	if (issue_flags & IO_URING_F_NONBLOCK)
546 		flags |= MSG_DONTWAIT;
547 	if (flags & MSG_WAITALL)
548 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
549 
550 	kmsg->msg.msg_control_user = sr->msg_control;
551 
552 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
553 
554 	if (ret < min_ret) {
555 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
556 			return -EAGAIN;
557 		if (ret > 0 && io_net_retry(sock, flags)) {
558 			kmsg->msg.msg_controllen = 0;
559 			kmsg->msg.msg_control = NULL;
560 			sr->done_io += ret;
561 			req->flags |= REQ_F_BL_NO_RECYCLE;
562 			return -EAGAIN;
563 		}
564 		if (ret == -ERESTARTSYS)
565 			ret = -EINTR;
566 		req_set_fail(req);
567 	}
568 	io_req_msg_cleanup(req, issue_flags);
569 	if (ret >= 0)
570 		ret += sr->done_io;
571 	else if (sr->done_io)
572 		ret = sr->done_io;
573 	io_req_set_res(req, ret, 0);
574 	return IOU_OK;
575 }
576 
577 int io_send(struct io_kiocb *req, unsigned int issue_flags)
578 {
579 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
580 	struct io_async_msghdr *kmsg = req->async_data;
581 	struct socket *sock;
582 	unsigned flags;
583 	int min_ret = 0;
584 	int ret;
585 
586 	sock = sock_from_file(req->file);
587 	if (unlikely(!sock))
588 		return -ENOTSOCK;
589 
590 	if (!(req->flags & REQ_F_POLLED) &&
591 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
592 		return -EAGAIN;
593 
594 	flags = sr->msg_flags;
595 	if (issue_flags & IO_URING_F_NONBLOCK)
596 		flags |= MSG_DONTWAIT;
597 
598 retry_bundle:
599 	if (io_do_buffer_select(req)) {
600 		struct buf_sel_arg arg = {
601 			.iovs = &kmsg->fast_iov,
602 			.max_len = INT_MAX,
603 			.nr_iovs = 1,
604 		};
605 
606 		if (kmsg->free_iov) {
607 			arg.nr_iovs = kmsg->free_iov_nr;
608 			arg.iovs = kmsg->free_iov;
609 			arg.mode = KBUF_MODE_FREE;
610 		}
611 
612 		if (!(sr->flags & IORING_RECVSEND_BUNDLE))
613 			arg.nr_iovs = 1;
614 		else
615 			arg.mode |= KBUF_MODE_EXPAND;
616 
617 		ret = io_buffers_select(req, &arg, issue_flags);
618 		if (unlikely(ret < 0))
619 			return ret;
620 
621 		sr->len = arg.out_len;
622 		iov_iter_init(&kmsg->msg.msg_iter, ITER_SOURCE, arg.iovs, ret,
623 				arg.out_len);
624 		if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) {
625 			kmsg->free_iov_nr = ret;
626 			kmsg->free_iov = arg.iovs;
627 			req->flags |= REQ_F_NEED_CLEANUP;
628 		}
629 	}
630 
631 	/*
632 	 * If MSG_WAITALL is set, or this is a bundle send, then we need
633 	 * the full amount. If just bundle is set, if we do a short send
634 	 * then we complete the bundle sequence rather than continue on.
635 	 */
636 	if (flags & MSG_WAITALL || sr->flags & IORING_RECVSEND_BUNDLE)
637 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
638 
639 	flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
640 	kmsg->msg.msg_flags = flags;
641 	ret = sock_sendmsg(sock, &kmsg->msg);
642 	if (ret < min_ret) {
643 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
644 			return -EAGAIN;
645 
646 		if (ret > 0 && io_net_retry(sock, flags)) {
647 			sr->len -= ret;
648 			sr->buf += ret;
649 			sr->done_io += ret;
650 			req->flags |= REQ_F_BL_NO_RECYCLE;
651 			return -EAGAIN;
652 		}
653 		if (ret == -ERESTARTSYS)
654 			ret = -EINTR;
655 		req_set_fail(req);
656 	}
657 	if (ret >= 0)
658 		ret += sr->done_io;
659 	else if (sr->done_io)
660 		ret = sr->done_io;
661 
662 	if (!io_send_finish(req, &ret, kmsg, issue_flags))
663 		goto retry_bundle;
664 
665 	io_req_msg_cleanup(req, issue_flags);
666 	return ret;
667 }
668 
669 static int io_recvmsg_mshot_prep(struct io_kiocb *req,
670 				 struct io_async_msghdr *iomsg,
671 				 int namelen, size_t controllen)
672 {
673 	if ((req->flags & (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) ==
674 			  (REQ_F_APOLL_MULTISHOT|REQ_F_BUFFER_SELECT)) {
675 		int hdr;
676 
677 		if (unlikely(namelen < 0))
678 			return -EOVERFLOW;
679 		if (check_add_overflow(sizeof(struct io_uring_recvmsg_out),
680 					namelen, &hdr))
681 			return -EOVERFLOW;
682 		if (check_add_overflow(hdr, controllen, &hdr))
683 			return -EOVERFLOW;
684 
685 		iomsg->namelen = namelen;
686 		iomsg->controllen = controllen;
687 		return 0;
688 	}
689 
690 	return 0;
691 }
692 
693 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
694 			       struct io_async_msghdr *iomsg)
695 {
696 	struct user_msghdr msg;
697 	int ret;
698 
699 	iomsg->msg.msg_name = &iomsg->addr;
700 	iomsg->msg.msg_iter.nr_segs = 0;
701 
702 #ifdef CONFIG_COMPAT
703 	if (unlikely(req->ctx->compat)) {
704 		struct compat_msghdr cmsg;
705 
706 		ret = io_compat_msg_copy_hdr(req, iomsg, &cmsg, ITER_DEST);
707 		if (unlikely(ret))
708 			return ret;
709 
710 		ret = __get_compat_msghdr(&iomsg->msg, &cmsg, &iomsg->uaddr);
711 		if (unlikely(ret))
712 			return ret;
713 
714 		return io_recvmsg_mshot_prep(req, iomsg, cmsg.msg_namelen,
715 						cmsg.msg_controllen);
716 	}
717 #endif
718 
719 	ret = io_msg_copy_hdr(req, iomsg, &msg, ITER_DEST);
720 	if (unlikely(ret))
721 		return ret;
722 
723 	ret = __copy_msghdr(&iomsg->msg, &msg, &iomsg->uaddr);
724 	if (unlikely(ret))
725 		return ret;
726 
727 	return io_recvmsg_mshot_prep(req, iomsg, msg.msg_namelen,
728 					msg.msg_controllen);
729 }
730 
731 static int io_recvmsg_prep_setup(struct io_kiocb *req)
732 {
733 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
734 	struct io_async_msghdr *kmsg;
735 	int ret;
736 
737 	kmsg = io_msg_alloc_async(req);
738 	if (unlikely(!kmsg))
739 		return -ENOMEM;
740 
741 	if (req->opcode == IORING_OP_RECV) {
742 		kmsg->msg.msg_name = NULL;
743 		kmsg->msg.msg_namelen = 0;
744 		kmsg->msg.msg_control = NULL;
745 		kmsg->msg.msg_get_inq = 1;
746 		kmsg->msg.msg_controllen = 0;
747 		kmsg->msg.msg_iocb = NULL;
748 		kmsg->msg.msg_ubuf = NULL;
749 
750 		if (!io_do_buffer_select(req)) {
751 			ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
752 					  &kmsg->msg.msg_iter);
753 			if (unlikely(ret))
754 				return ret;
755 		}
756 		return 0;
757 	}
758 
759 	ret = io_recvmsg_copy_hdr(req, kmsg);
760 	if (!ret)
761 		req->flags |= REQ_F_NEED_CLEANUP;
762 	return ret;
763 }
764 
765 #define RECVMSG_FLAGS (IORING_RECVSEND_POLL_FIRST | IORING_RECV_MULTISHOT | \
766 			IORING_RECVSEND_BUNDLE)
767 
768 int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
769 {
770 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
771 
772 	sr->done_io = 0;
773 
774 	if (unlikely(sqe->file_index || sqe->addr2))
775 		return -EINVAL;
776 
777 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
778 	sr->len = READ_ONCE(sqe->len);
779 	sr->flags = READ_ONCE(sqe->ioprio);
780 	if (sr->flags & ~RECVMSG_FLAGS)
781 		return -EINVAL;
782 	sr->msg_flags = READ_ONCE(sqe->msg_flags);
783 	if (sr->msg_flags & MSG_DONTWAIT)
784 		req->flags |= REQ_F_NOWAIT;
785 	if (sr->msg_flags & MSG_ERRQUEUE)
786 		req->flags |= REQ_F_CLEAR_POLLIN;
787 	if (req->flags & REQ_F_BUFFER_SELECT) {
788 		/*
789 		 * Store the buffer group for this multishot receive separately,
790 		 * as if we end up doing an io-wq based issue that selects a
791 		 * buffer, it has to be committed immediately and that will
792 		 * clear ->buf_list. This means we lose the link to the buffer
793 		 * list, and the eventual buffer put on completion then cannot
794 		 * restore it.
795 		 */
796 		sr->buf_group = req->buf_index;
797 		req->buf_list = NULL;
798 	}
799 	if (sr->flags & IORING_RECV_MULTISHOT) {
800 		if (!(req->flags & REQ_F_BUFFER_SELECT))
801 			return -EINVAL;
802 		if (sr->msg_flags & MSG_WAITALL)
803 			return -EINVAL;
804 		if (req->opcode == IORING_OP_RECV && sr->len)
805 			return -EINVAL;
806 		req->flags |= REQ_F_APOLL_MULTISHOT;
807 	}
808 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
809 		if (req->opcode == IORING_OP_RECVMSG)
810 			return -EINVAL;
811 	}
812 
813 #ifdef CONFIG_COMPAT
814 	if (req->ctx->compat)
815 		sr->msg_flags |= MSG_CMSG_COMPAT;
816 #endif
817 	sr->nr_multishot_loops = 0;
818 	return io_recvmsg_prep_setup(req);
819 }
820 
821 /*
822  * Finishes io_recv and io_recvmsg.
823  *
824  * Returns true if it is actually finished, or false if it should run
825  * again (for multishot).
826  */
827 static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
828 				  struct io_async_msghdr *kmsg,
829 				  bool mshot_finished, unsigned issue_flags)
830 {
831 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
832 	unsigned int cflags = 0;
833 
834 	if (kmsg->msg.msg_inq > 0)
835 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
836 
837 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
838 		cflags |= io_put_kbufs(req, io_bundle_nbufs(kmsg, *ret),
839 				      issue_flags);
840 		/* bundle with no more immediate buffers, we're done */
841 		if (req->flags & REQ_F_BL_EMPTY)
842 			goto finish;
843 	} else {
844 		cflags |= io_put_kbuf(req, issue_flags);
845 	}
846 
847 	/*
848 	 * Fill CQE for this receive and see if we should keep trying to
849 	 * receive from this socket.
850 	 */
851 	if ((req->flags & REQ_F_APOLL_MULTISHOT) && !mshot_finished &&
852 	    io_req_post_cqe(req, *ret, cflags | IORING_CQE_F_MORE)) {
853 		int mshot_retry_ret = IOU_ISSUE_SKIP_COMPLETE;
854 
855 		io_mshot_prep_retry(req, kmsg);
856 		/* Known not-empty or unknown state, retry */
857 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || kmsg->msg.msg_inq < 0) {
858 			if (sr->nr_multishot_loops++ < MULTISHOT_MAX_RETRY)
859 				return false;
860 			/* mshot retries exceeded, force a requeue */
861 			sr->nr_multishot_loops = 0;
862 			mshot_retry_ret = IOU_REQUEUE;
863 		}
864 		if (issue_flags & IO_URING_F_MULTISHOT)
865 			*ret = mshot_retry_ret;
866 		else
867 			*ret = -EAGAIN;
868 		return true;
869 	}
870 
871 	/* Finish the request / stop multishot. */
872 finish:
873 	io_req_set_res(req, *ret, cflags);
874 
875 	if (issue_flags & IO_URING_F_MULTISHOT)
876 		*ret = IOU_STOP_MULTISHOT;
877 	else
878 		*ret = IOU_OK;
879 	io_req_msg_cleanup(req, issue_flags);
880 	return true;
881 }
882 
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 
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 
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 				return IOU_ISSUE_SKIP_COMPLETE;
1028 			}
1029 			return -EAGAIN;
1030 		}
1031 		if (ret > 0 && io_net_retry(sock, flags)) {
1032 			sr->done_io += ret;
1033 			req->flags |= REQ_F_BL_NO_RECYCLE;
1034 			return -EAGAIN;
1035 		}
1036 		if (ret == -ERESTARTSYS)
1037 			ret = -EINTR;
1038 		req_set_fail(req);
1039 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1040 		req_set_fail(req);
1041 	}
1042 
1043 	if (ret > 0)
1044 		ret += sr->done_io;
1045 	else if (sr->done_io)
1046 		ret = sr->done_io;
1047 	else
1048 		io_kbuf_recycle(req, issue_flags);
1049 
1050 	if (!io_recv_finish(req, &ret, kmsg, mshot_finished, issue_flags))
1051 		goto retry_multishot;
1052 
1053 	return ret;
1054 }
1055 
1056 static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg,
1057 			      size_t *len, unsigned int issue_flags)
1058 {
1059 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1060 	int ret;
1061 
1062 	/*
1063 	 * If the ring isn't locked, then don't use the peek interface
1064 	 * to grab multiple buffers as we will lock/unlock between
1065 	 * this selection and posting the buffers.
1066 	 */
1067 	if (!(issue_flags & IO_URING_F_UNLOCKED) &&
1068 	    sr->flags & IORING_RECVSEND_BUNDLE) {
1069 		struct buf_sel_arg arg = {
1070 			.iovs = &kmsg->fast_iov,
1071 			.nr_iovs = 1,
1072 			.mode = KBUF_MODE_EXPAND,
1073 		};
1074 
1075 		if (kmsg->free_iov) {
1076 			arg.nr_iovs = kmsg->free_iov_nr;
1077 			arg.iovs = kmsg->free_iov;
1078 			arg.mode |= KBUF_MODE_FREE;
1079 		}
1080 
1081 		if (kmsg->msg.msg_inq > 0)
1082 			arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq);
1083 
1084 		ret = io_buffers_peek(req, &arg);
1085 		if (unlikely(ret < 0))
1086 			return ret;
1087 
1088 		/* special case 1 vec, can be a fast path */
1089 		if (ret == 1) {
1090 			sr->buf = arg.iovs[0].iov_base;
1091 			sr->len = arg.iovs[0].iov_len;
1092 			goto map_ubuf;
1093 		}
1094 		iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, arg.iovs, ret,
1095 				arg.out_len);
1096 		if (arg.iovs != &kmsg->fast_iov && arg.iovs != kmsg->free_iov) {
1097 			kmsg->free_iov_nr = ret;
1098 			kmsg->free_iov = arg.iovs;
1099 			req->flags |= REQ_F_NEED_CLEANUP;
1100 		}
1101 	} else {
1102 		void __user *buf;
1103 
1104 		*len = sr->len;
1105 		buf = io_buffer_select(req, len, issue_flags);
1106 		if (!buf)
1107 			return -ENOBUFS;
1108 		sr->buf = buf;
1109 		sr->len = *len;
1110 map_ubuf:
1111 		ret = import_ubuf(ITER_DEST, sr->buf, sr->len,
1112 				  &kmsg->msg.msg_iter);
1113 		if (unlikely(ret))
1114 			return ret;
1115 	}
1116 
1117 	return 0;
1118 }
1119 
1120 int io_recv(struct io_kiocb *req, unsigned int issue_flags)
1121 {
1122 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1123 	struct io_async_msghdr *kmsg = req->async_data;
1124 	struct socket *sock;
1125 	unsigned flags;
1126 	int ret, min_ret = 0;
1127 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1128 	size_t len = sr->len;
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 				return IOU_ISSUE_SKIP_COMPLETE;
1164 			}
1165 
1166 			return -EAGAIN;
1167 		}
1168 		if (ret > 0 && io_net_retry(sock, flags)) {
1169 			sr->len -= ret;
1170 			sr->buf += ret;
1171 			sr->done_io += ret;
1172 			req->flags |= REQ_F_BL_NO_RECYCLE;
1173 			return -EAGAIN;
1174 		}
1175 		if (ret == -ERESTARTSYS)
1176 			ret = -EINTR;
1177 		req_set_fail(req);
1178 	} else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
1179 out_free:
1180 		req_set_fail(req);
1181 	}
1182 
1183 	if (ret > 0)
1184 		ret += sr->done_io;
1185 	else if (sr->done_io)
1186 		ret = sr->done_io;
1187 	else
1188 		io_kbuf_recycle(req, issue_flags);
1189 
1190 	if (!io_recv_finish(req, &ret, kmsg, ret <= 0, issue_flags))
1191 		goto retry_multishot;
1192 
1193 	return ret;
1194 }
1195 
1196 void io_send_zc_cleanup(struct io_kiocb *req)
1197 {
1198 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1199 	struct io_async_msghdr *io = req->async_data;
1200 
1201 	if (req_has_async_data(req))
1202 		io_netmsg_iovec_free(io);
1203 	if (zc->notif) {
1204 		io_notif_flush(zc->notif);
1205 		zc->notif = NULL;
1206 	}
1207 }
1208 
1209 #define IO_ZC_FLAGS_COMMON (IORING_RECVSEND_POLL_FIRST | IORING_RECVSEND_FIXED_BUF)
1210 #define IO_ZC_FLAGS_VALID  (IO_ZC_FLAGS_COMMON | IORING_SEND_ZC_REPORT_USAGE)
1211 
1212 int io_send_zc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1213 {
1214 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1215 	struct io_ring_ctx *ctx = req->ctx;
1216 	struct io_kiocb *notif;
1217 
1218 	zc->done_io = 0;
1219 	req->flags |= REQ_F_POLL_NO_LAZY;
1220 
1221 	if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3)))
1222 		return -EINVAL;
1223 	/* we don't support IOSQE_CQE_SKIP_SUCCESS just yet */
1224 	if (req->flags & REQ_F_CQE_SKIP)
1225 		return -EINVAL;
1226 
1227 	notif = zc->notif = io_alloc_notif(ctx);
1228 	if (!notif)
1229 		return -ENOMEM;
1230 	notif->cqe.user_data = req->cqe.user_data;
1231 	notif->cqe.res = 0;
1232 	notif->cqe.flags = IORING_CQE_F_NOTIF;
1233 	req->flags |= REQ_F_NEED_CLEANUP;
1234 
1235 	zc->flags = READ_ONCE(sqe->ioprio);
1236 	if (unlikely(zc->flags & ~IO_ZC_FLAGS_COMMON)) {
1237 		if (zc->flags & ~IO_ZC_FLAGS_VALID)
1238 			return -EINVAL;
1239 		if (zc->flags & IORING_SEND_ZC_REPORT_USAGE) {
1240 			struct io_notif_data *nd = io_notif_to_data(notif);
1241 
1242 			nd->zc_report = true;
1243 			nd->zc_used = false;
1244 			nd->zc_copied = false;
1245 		}
1246 	}
1247 
1248 	if (zc->flags & IORING_RECVSEND_FIXED_BUF) {
1249 		unsigned idx = READ_ONCE(sqe->buf_index);
1250 
1251 		if (unlikely(idx >= ctx->nr_user_bufs))
1252 			return -EFAULT;
1253 		idx = array_index_nospec(idx, ctx->nr_user_bufs);
1254 		req->imu = READ_ONCE(ctx->user_bufs[idx]);
1255 		io_req_set_rsrc_node(notif, ctx, 0);
1256 	}
1257 
1258 	if (req->opcode == IORING_OP_SEND_ZC) {
1259 		if (READ_ONCE(sqe->__pad3[0]))
1260 			return -EINVAL;
1261 		zc->addr = u64_to_user_ptr(READ_ONCE(sqe->addr2));
1262 		zc->addr_len = READ_ONCE(sqe->addr_len);
1263 	} else {
1264 		if (unlikely(sqe->addr2 || sqe->file_index))
1265 			return -EINVAL;
1266 		if (unlikely(zc->flags & IORING_RECVSEND_FIXED_BUF))
1267 			return -EINVAL;
1268 	}
1269 
1270 	zc->buf = u64_to_user_ptr(READ_ONCE(sqe->addr));
1271 	zc->len = READ_ONCE(sqe->len);
1272 	zc->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL | MSG_ZEROCOPY;
1273 	if (zc->msg_flags & MSG_DONTWAIT)
1274 		req->flags |= REQ_F_NOWAIT;
1275 
1276 #ifdef CONFIG_COMPAT
1277 	if (req->ctx->compat)
1278 		zc->msg_flags |= MSG_CMSG_COMPAT;
1279 #endif
1280 	return io_sendmsg_prep_setup(req, req->opcode == IORING_OP_SENDMSG_ZC);
1281 }
1282 
1283 static int io_sg_from_iter_iovec(struct sk_buff *skb,
1284 				 struct iov_iter *from, size_t length)
1285 {
1286 	skb_zcopy_downgrade_managed(skb);
1287 	return zerocopy_fill_skb_from_iter(skb, from, length);
1288 }
1289 
1290 static int io_sg_from_iter(struct sk_buff *skb,
1291 			   struct iov_iter *from, size_t length)
1292 {
1293 	struct skb_shared_info *shinfo = skb_shinfo(skb);
1294 	int frag = shinfo->nr_frags;
1295 	int ret = 0;
1296 	struct bvec_iter bi;
1297 	ssize_t copied = 0;
1298 	unsigned long truesize = 0;
1299 
1300 	if (!frag)
1301 		shinfo->flags |= SKBFL_MANAGED_FRAG_REFS;
1302 	else if (unlikely(!skb_zcopy_managed(skb)))
1303 		return zerocopy_fill_skb_from_iter(skb, from, length);
1304 
1305 	bi.bi_size = min(from->count, length);
1306 	bi.bi_bvec_done = from->iov_offset;
1307 	bi.bi_idx = 0;
1308 
1309 	while (bi.bi_size && frag < MAX_SKB_FRAGS) {
1310 		struct bio_vec v = mp_bvec_iter_bvec(from->bvec, bi);
1311 
1312 		copied += v.bv_len;
1313 		truesize += PAGE_ALIGN(v.bv_len + v.bv_offset);
1314 		__skb_fill_page_desc_noacc(shinfo, frag++, v.bv_page,
1315 					   v.bv_offset, v.bv_len);
1316 		bvec_iter_advance_single(from->bvec, &bi, v.bv_len);
1317 	}
1318 	if (bi.bi_size)
1319 		ret = -EMSGSIZE;
1320 
1321 	shinfo->nr_frags = frag;
1322 	from->bvec += bi.bi_idx;
1323 	from->nr_segs -= bi.bi_idx;
1324 	from->count -= copied;
1325 	from->iov_offset = bi.bi_bvec_done;
1326 
1327 	skb->data_len += copied;
1328 	skb->len += copied;
1329 	skb->truesize += truesize;
1330 	return ret;
1331 }
1332 
1333 static int io_send_zc_import(struct io_kiocb *req, struct io_async_msghdr *kmsg)
1334 {
1335 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1336 	int ret;
1337 
1338 	if (sr->flags & IORING_RECVSEND_FIXED_BUF) {
1339 		ret = io_import_fixed(ITER_SOURCE, &kmsg->msg.msg_iter, req->imu,
1340 					(u64)(uintptr_t)sr->buf, sr->len);
1341 		if (unlikely(ret))
1342 			return ret;
1343 		kmsg->msg.sg_from_iter = io_sg_from_iter;
1344 	} else {
1345 		ret = import_ubuf(ITER_SOURCE, sr->buf, sr->len, &kmsg->msg.msg_iter);
1346 		if (unlikely(ret))
1347 			return ret;
1348 		ret = io_notif_account_mem(sr->notif, sr->len);
1349 		if (unlikely(ret))
1350 			return ret;
1351 		kmsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1352 	}
1353 
1354 	return ret;
1355 }
1356 
1357 int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
1358 {
1359 	struct io_sr_msg *zc = io_kiocb_to_cmd(req, struct io_sr_msg);
1360 	struct io_async_msghdr *kmsg = req->async_data;
1361 	struct socket *sock;
1362 	unsigned msg_flags;
1363 	int ret, min_ret = 0;
1364 
1365 	sock = sock_from_file(req->file);
1366 	if (unlikely(!sock))
1367 		return -ENOTSOCK;
1368 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1369 		return -EOPNOTSUPP;
1370 
1371 	if (!(req->flags & REQ_F_POLLED) &&
1372 	    (zc->flags & IORING_RECVSEND_POLL_FIRST))
1373 		return -EAGAIN;
1374 
1375 	if (!zc->done_io) {
1376 		ret = io_send_zc_import(req, kmsg);
1377 		if (unlikely(ret))
1378 			return ret;
1379 	}
1380 
1381 	msg_flags = zc->msg_flags;
1382 	if (issue_flags & IO_URING_F_NONBLOCK)
1383 		msg_flags |= MSG_DONTWAIT;
1384 	if (msg_flags & MSG_WAITALL)
1385 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1386 	msg_flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
1387 
1388 	kmsg->msg.msg_flags = msg_flags;
1389 	kmsg->msg.msg_ubuf = &io_notif_to_data(zc->notif)->uarg;
1390 	ret = sock_sendmsg(sock, &kmsg->msg);
1391 
1392 	if (unlikely(ret < min_ret)) {
1393 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1394 			return -EAGAIN;
1395 
1396 		if (ret > 0 && io_net_retry(sock, kmsg->msg.msg_flags)) {
1397 			zc->len -= ret;
1398 			zc->buf += ret;
1399 			zc->done_io += ret;
1400 			req->flags |= REQ_F_BL_NO_RECYCLE;
1401 			return -EAGAIN;
1402 		}
1403 		if (ret == -ERESTARTSYS)
1404 			ret = -EINTR;
1405 		req_set_fail(req);
1406 	}
1407 
1408 	if (ret >= 0)
1409 		ret += zc->done_io;
1410 	else if (zc->done_io)
1411 		ret = zc->done_io;
1412 
1413 	/*
1414 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1415 	 * flushing notif to io_send_zc_cleanup()
1416 	 */
1417 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1418 		io_notif_flush(zc->notif);
1419 		io_req_msg_cleanup(req, 0);
1420 	}
1421 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1422 	return IOU_OK;
1423 }
1424 
1425 int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags)
1426 {
1427 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1428 	struct io_async_msghdr *kmsg = req->async_data;
1429 	struct socket *sock;
1430 	unsigned flags;
1431 	int ret, min_ret = 0;
1432 
1433 	sock = sock_from_file(req->file);
1434 	if (unlikely(!sock))
1435 		return -ENOTSOCK;
1436 	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
1437 		return -EOPNOTSUPP;
1438 
1439 	if (!(req->flags & REQ_F_POLLED) &&
1440 	    (sr->flags & IORING_RECVSEND_POLL_FIRST))
1441 		return -EAGAIN;
1442 
1443 	flags = sr->msg_flags;
1444 	if (issue_flags & IO_URING_F_NONBLOCK)
1445 		flags |= MSG_DONTWAIT;
1446 	if (flags & MSG_WAITALL)
1447 		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
1448 
1449 	kmsg->msg.msg_control_user = sr->msg_control;
1450 	kmsg->msg.msg_ubuf = &io_notif_to_data(sr->notif)->uarg;
1451 	kmsg->msg.sg_from_iter = io_sg_from_iter_iovec;
1452 	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
1453 
1454 	if (unlikely(ret < min_ret)) {
1455 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1456 			return -EAGAIN;
1457 
1458 		if (ret > 0 && io_net_retry(sock, flags)) {
1459 			sr->done_io += ret;
1460 			req->flags |= REQ_F_BL_NO_RECYCLE;
1461 			return -EAGAIN;
1462 		}
1463 		if (ret == -ERESTARTSYS)
1464 			ret = -EINTR;
1465 		req_set_fail(req);
1466 	}
1467 
1468 	if (ret >= 0)
1469 		ret += sr->done_io;
1470 	else if (sr->done_io)
1471 		ret = sr->done_io;
1472 
1473 	/*
1474 	 * If we're in io-wq we can't rely on tw ordering guarantees, defer
1475 	 * flushing notif to io_send_zc_cleanup()
1476 	 */
1477 	if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1478 		io_notif_flush(sr->notif);
1479 		io_req_msg_cleanup(req, 0);
1480 	}
1481 	io_req_set_res(req, ret, IORING_CQE_F_MORE);
1482 	return IOU_OK;
1483 }
1484 
1485 void io_sendrecv_fail(struct io_kiocb *req)
1486 {
1487 	struct io_sr_msg *sr = io_kiocb_to_cmd(req, struct io_sr_msg);
1488 
1489 	if (sr->done_io)
1490 		req->cqe.res = sr->done_io;
1491 
1492 	if ((req->flags & REQ_F_NEED_CLEANUP) &&
1493 	    (req->opcode == IORING_OP_SEND_ZC || req->opcode == IORING_OP_SENDMSG_ZC))
1494 		req->cqe.flags |= IORING_CQE_F_MORE;
1495 }
1496 
1497 #define ACCEPT_FLAGS	(IORING_ACCEPT_MULTISHOT | IORING_ACCEPT_DONTWAIT | \
1498 			 IORING_ACCEPT_POLL_FIRST)
1499 
1500 int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1501 {
1502 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1503 
1504 	if (sqe->len || sqe->buf_index)
1505 		return -EINVAL;
1506 
1507 	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1508 	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
1509 	accept->flags = READ_ONCE(sqe->accept_flags);
1510 	accept->nofile = rlimit(RLIMIT_NOFILE);
1511 	accept->iou_flags = READ_ONCE(sqe->ioprio);
1512 	if (accept->iou_flags & ~ACCEPT_FLAGS)
1513 		return -EINVAL;
1514 
1515 	accept->file_slot = READ_ONCE(sqe->file_index);
1516 	if (accept->file_slot) {
1517 		if (accept->flags & SOCK_CLOEXEC)
1518 			return -EINVAL;
1519 		if (accept->iou_flags & IORING_ACCEPT_MULTISHOT &&
1520 		    accept->file_slot != IORING_FILE_INDEX_ALLOC)
1521 			return -EINVAL;
1522 	}
1523 	if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1524 		return -EINVAL;
1525 	if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
1526 		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1527 	if (accept->iou_flags & IORING_ACCEPT_MULTISHOT)
1528 		req->flags |= REQ_F_APOLL_MULTISHOT;
1529 	if (accept->iou_flags & IORING_ACCEPT_DONTWAIT)
1530 		req->flags |= REQ_F_NOWAIT;
1531 	return 0;
1532 }
1533 
1534 int io_accept(struct io_kiocb *req, unsigned int issue_flags)
1535 {
1536 	struct io_accept *accept = io_kiocb_to_cmd(req, struct io_accept);
1537 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1538 	bool fixed = !!accept->file_slot;
1539 	struct proto_accept_arg arg = {
1540 		.flags = force_nonblock ? O_NONBLOCK : 0,
1541 	};
1542 	struct file *file;
1543 	unsigned cflags;
1544 	int ret, fd;
1545 
1546 	if (!(req->flags & REQ_F_POLLED) &&
1547 	    accept->iou_flags & IORING_ACCEPT_POLL_FIRST)
1548 		return -EAGAIN;
1549 
1550 retry:
1551 	if (!fixed) {
1552 		fd = __get_unused_fd_flags(accept->flags, accept->nofile);
1553 		if (unlikely(fd < 0))
1554 			return fd;
1555 	}
1556 	arg.err = 0;
1557 	arg.is_empty = -1;
1558 	file = do_accept(req->file, &arg, accept->addr, accept->addr_len,
1559 			 accept->flags);
1560 	if (IS_ERR(file)) {
1561 		if (!fixed)
1562 			put_unused_fd(fd);
1563 		ret = PTR_ERR(file);
1564 		if (ret == -EAGAIN && force_nonblock &&
1565 		    !(accept->iou_flags & IORING_ACCEPT_DONTWAIT)) {
1566 			/*
1567 			 * if it's multishot and polled, we don't need to
1568 			 * return EAGAIN to arm the poll infra since it
1569 			 * has already been done
1570 			 */
1571 			if (issue_flags & IO_URING_F_MULTISHOT)
1572 				return IOU_ISSUE_SKIP_COMPLETE;
1573 			return ret;
1574 		}
1575 		if (ret == -ERESTARTSYS)
1576 			ret = -EINTR;
1577 		req_set_fail(req);
1578 	} else if (!fixed) {
1579 		fd_install(fd, file);
1580 		ret = fd;
1581 	} else {
1582 		ret = io_fixed_fd_install(req, issue_flags, file,
1583 						accept->file_slot);
1584 	}
1585 
1586 	cflags = 0;
1587 	if (!arg.is_empty)
1588 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
1589 
1590 	if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
1591 		io_req_set_res(req, ret, cflags);
1592 		return IOU_OK;
1593 	}
1594 
1595 	if (ret < 0)
1596 		return ret;
1597 	if (io_req_post_cqe(req, ret, cflags | IORING_CQE_F_MORE)) {
1598 		if (cflags & IORING_CQE_F_SOCK_NONEMPTY || arg.is_empty == -1)
1599 			goto retry;
1600 		if (issue_flags & IO_URING_F_MULTISHOT)
1601 			return IOU_ISSUE_SKIP_COMPLETE;
1602 		return -EAGAIN;
1603 	}
1604 
1605 	io_req_set_res(req, ret, cflags);
1606 	return IOU_STOP_MULTISHOT;
1607 }
1608 
1609 int io_socket_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1610 {
1611 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1612 
1613 	if (sqe->addr || sqe->rw_flags || sqe->buf_index)
1614 		return -EINVAL;
1615 
1616 	sock->domain = READ_ONCE(sqe->fd);
1617 	sock->type = READ_ONCE(sqe->off);
1618 	sock->protocol = READ_ONCE(sqe->len);
1619 	sock->file_slot = READ_ONCE(sqe->file_index);
1620 	sock->nofile = rlimit(RLIMIT_NOFILE);
1621 
1622 	sock->flags = sock->type & ~SOCK_TYPE_MASK;
1623 	if (sock->file_slot && (sock->flags & SOCK_CLOEXEC))
1624 		return -EINVAL;
1625 	if (sock->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1626 		return -EINVAL;
1627 	return 0;
1628 }
1629 
1630 int io_socket(struct io_kiocb *req, unsigned int issue_flags)
1631 {
1632 	struct io_socket *sock = io_kiocb_to_cmd(req, struct io_socket);
1633 	bool fixed = !!sock->file_slot;
1634 	struct file *file;
1635 	int ret, fd;
1636 
1637 	if (!fixed) {
1638 		fd = __get_unused_fd_flags(sock->flags, sock->nofile);
1639 		if (unlikely(fd < 0))
1640 			return fd;
1641 	}
1642 	file = __sys_socket_file(sock->domain, sock->type, sock->protocol);
1643 	if (IS_ERR(file)) {
1644 		if (!fixed)
1645 			put_unused_fd(fd);
1646 		ret = PTR_ERR(file);
1647 		if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
1648 			return -EAGAIN;
1649 		if (ret == -ERESTARTSYS)
1650 			ret = -EINTR;
1651 		req_set_fail(req);
1652 	} else if (!fixed) {
1653 		fd_install(fd, file);
1654 		ret = fd;
1655 	} else {
1656 		ret = io_fixed_fd_install(req, issue_flags, file,
1657 					    sock->file_slot);
1658 	}
1659 	io_req_set_res(req, ret, 0);
1660 	return IOU_OK;
1661 }
1662 
1663 int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1664 {
1665 	struct io_connect *conn = io_kiocb_to_cmd(req, struct io_connect);
1666 	struct io_async_msghdr *io;
1667 
1668 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1669 		return -EINVAL;
1670 
1671 	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1672 	conn->addr_len =  READ_ONCE(sqe->addr2);
1673 	conn->in_progress = conn->seen_econnaborted = false;
1674 
1675 	io = io_msg_alloc_async(req);
1676 	if (unlikely(!io))
1677 		return -ENOMEM;
1678 
1679 	return move_addr_to_kernel(conn->addr, conn->addr_len, &io->addr);
1680 }
1681 
1682 int io_connect(struct io_kiocb *req, unsigned int issue_flags)
1683 {
1684 	struct io_connect *connect = io_kiocb_to_cmd(req, struct io_connect);
1685 	struct io_async_msghdr *io = req->async_data;
1686 	unsigned file_flags;
1687 	int ret;
1688 	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
1689 
1690 	file_flags = force_nonblock ? O_NONBLOCK : 0;
1691 
1692 	ret = __sys_connect_file(req->file, &io->addr, connect->addr_len,
1693 				 file_flags);
1694 	if ((ret == -EAGAIN || ret == -EINPROGRESS || ret == -ECONNABORTED)
1695 	    && force_nonblock) {
1696 		if (ret == -EINPROGRESS) {
1697 			connect->in_progress = true;
1698 		} else if (ret == -ECONNABORTED) {
1699 			if (connect->seen_econnaborted)
1700 				goto out;
1701 			connect->seen_econnaborted = true;
1702 		}
1703 		return -EAGAIN;
1704 	}
1705 	if (connect->in_progress) {
1706 		/*
1707 		 * At least bluetooth will return -EBADFD on a re-connect
1708 		 * attempt, and it's (supposedly) also valid to get -EISCONN
1709 		 * which means the previous result is good. For both of these,
1710 		 * grab the sock_error() and use that for the completion.
1711 		 */
1712 		if (ret == -EBADFD || ret == -EISCONN)
1713 			ret = sock_error(sock_from_file(req->file)->sk);
1714 	}
1715 	if (ret == -ERESTARTSYS)
1716 		ret = -EINTR;
1717 out:
1718 	if (ret < 0)
1719 		req_set_fail(req);
1720 	io_req_msg_cleanup(req, issue_flags);
1721 	io_req_set_res(req, ret, 0);
1722 	return IOU_OK;
1723 }
1724 
1725 int io_bind_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1726 {
1727 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1728 	struct sockaddr __user *uaddr;
1729 	struct io_async_msghdr *io;
1730 
1731 	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
1732 		return -EINVAL;
1733 
1734 	uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr));
1735 	bind->addr_len =  READ_ONCE(sqe->addr2);
1736 
1737 	io = io_msg_alloc_async(req);
1738 	if (unlikely(!io))
1739 		return -ENOMEM;
1740 	return move_addr_to_kernel(uaddr, bind->addr_len, &io->addr);
1741 }
1742 
1743 int io_bind(struct io_kiocb *req, unsigned int issue_flags)
1744 {
1745 	struct io_bind *bind = io_kiocb_to_cmd(req, struct io_bind);
1746 	struct io_async_msghdr *io = req->async_data;
1747 	struct socket *sock;
1748 	int ret;
1749 
1750 	sock = sock_from_file(req->file);
1751 	if (unlikely(!sock))
1752 		return -ENOTSOCK;
1753 
1754 	ret = __sys_bind_socket(sock, &io->addr, bind->addr_len);
1755 	if (ret < 0)
1756 		req_set_fail(req);
1757 	io_req_set_res(req, ret, 0);
1758 	return 0;
1759 }
1760 
1761 int io_listen_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
1762 {
1763 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1764 
1765 	if (sqe->addr || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in || sqe->addr2)
1766 		return -EINVAL;
1767 
1768 	listen->backlog = READ_ONCE(sqe->len);
1769 	return 0;
1770 }
1771 
1772 int io_listen(struct io_kiocb *req, unsigned int issue_flags)
1773 {
1774 	struct io_listen *listen = io_kiocb_to_cmd(req, struct io_listen);
1775 	struct socket *sock;
1776 	int ret;
1777 
1778 	sock = sock_from_file(req->file);
1779 	if (unlikely(!sock))
1780 		return -ENOTSOCK;
1781 
1782 	ret = __sys_listen_socket(sock, listen->backlog);
1783 	if (ret < 0)
1784 		req_set_fail(req);
1785 	io_req_set_res(req, ret, 0);
1786 	return 0;
1787 }
1788 
1789 void io_netmsg_cache_free(const void *entry)
1790 {
1791 	struct io_async_msghdr *kmsg = (struct io_async_msghdr *) entry;
1792 
1793 	if (kmsg->free_iov) {
1794 		kasan_mempool_unpoison_object(kmsg->free_iov,
1795 				kmsg->free_iov_nr * sizeof(struct iovec));
1796 		io_netmsg_iovec_free(kmsg);
1797 	}
1798 	kfree(kmsg);
1799 }
1800 #endif
1801