xref: /openbmc/linux/net/socket.c (revision c2e6c856)
1 /*
2  * NET		An implementation of the SOCKET network access protocol.
3  *
4  * Version:	@(#)socket.c	1.1.93	18/02/95
5  *
6  * Authors:	Orest Zborowski, <obz@Kodak.COM>
7  *		Ross Biro
8  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
9  *
10  * Fixes:
11  *		Anonymous	:	NOTSOCK/BADF cleanup. Error fix in
12  *					shutdown()
13  *		Alan Cox	:	verify_area() fixes
14  *		Alan Cox	:	Removed DDI
15  *		Jonathan Kamens	:	SOCK_DGRAM reconnect bug
16  *		Alan Cox	:	Moved a load of checks to the very
17  *					top level.
18  *		Alan Cox	:	Move address structures to/from user
19  *					mode above the protocol layers.
20  *		Rob Janssen	:	Allow 0 length sends.
21  *		Alan Cox	:	Asynchronous I/O support (cribbed from the
22  *					tty drivers).
23  *		Niibe Yutaka	:	Asynchronous I/O for writes (4.4BSD style)
24  *		Jeff Uphoff	:	Made max number of sockets command-line
25  *					configurable.
26  *		Matti Aarnio	:	Made the number of sockets dynamic,
27  *					to be allocated when needed, and mr.
28  *					Uphoff's max is used as max to be
29  *					allowed to allocate.
30  *		Linus		:	Argh. removed all the socket allocation
31  *					altogether: it's in the inode now.
32  *		Alan Cox	:	Made sock_alloc()/sock_release() public
33  *					for NetROM and future kernel nfsd type
34  *					stuff.
35  *		Alan Cox	:	sendmsg/recvmsg basics.
36  *		Tom Dyas	:	Export net symbols.
37  *		Marcin Dalecki	:	Fixed problems with CONFIG_NET="n".
38  *		Alan Cox	:	Added thread locking to sys_* calls
39  *					for sockets. May have errors at the
40  *					moment.
41  *		Kevin Buhr	:	Fixed the dumb errors in the above.
42  *		Andi Kleen	:	Some small cleanups, optimizations,
43  *					and fixed a copy_from_user() bug.
44  *		Tigran Aivazian	:	sys_send(args) calls sys_sendto(args, NULL, 0)
45  *		Tigran Aivazian	:	Made listen(2) backlog sanity checks
46  *					protocol-independent
47  *
48  *
49  *		This program is free software; you can redistribute it and/or
50  *		modify it under the terms of the GNU General Public License
51  *		as published by the Free Software Foundation; either version
52  *		2 of the License, or (at your option) any later version.
53  *
54  *
55  *	This module is effectively the top level interface to the BSD socket
56  *	paradigm.
57  *
58  *	Based upon Swansea University Computer Society NET3.039
59  */
60 
61 #include <linux/mm.h>
62 #include <linux/socket.h>
63 #include <linux/file.h>
64 #include <linux/net.h>
65 #include <linux/interrupt.h>
66 #include <linux/thread_info.h>
67 #include <linux/rcupdate.h>
68 #include <linux/netdevice.h>
69 #include <linux/proc_fs.h>
70 #include <linux/seq_file.h>
71 #include <linux/mutex.h>
72 #include <linux/if_bridge.h>
73 #include <linux/if_frad.h>
74 #include <linux/if_vlan.h>
75 #include <linux/ptp_classify.h>
76 #include <linux/init.h>
77 #include <linux/poll.h>
78 #include <linux/cache.h>
79 #include <linux/module.h>
80 #include <linux/highmem.h>
81 #include <linux/mount.h>
82 #include <linux/security.h>
83 #include <linux/syscalls.h>
84 #include <linux/compat.h>
85 #include <linux/kmod.h>
86 #include <linux/audit.h>
87 #include <linux/wireless.h>
88 #include <linux/nsproxy.h>
89 #include <linux/magic.h>
90 #include <linux/slab.h>
91 #include <linux/xattr.h>
92 #include <linux/nospec.h>
93 
94 #include <linux/uaccess.h>
95 #include <asm/unistd.h>
96 
97 #include <net/compat.h>
98 #include <net/wext.h>
99 #include <net/cls_cgroup.h>
100 
101 #include <net/sock.h>
102 #include <linux/netfilter.h>
103 
104 #include <linux/if_tun.h>
105 #include <linux/ipv6_route.h>
106 #include <linux/route.h>
107 #include <linux/sockios.h>
108 #include <net/busy_poll.h>
109 #include <linux/errqueue.h>
110 
111 #ifdef CONFIG_NET_RX_BUSY_POLL
112 unsigned int sysctl_net_busy_read __read_mostly;
113 unsigned int sysctl_net_busy_poll __read_mostly;
114 #endif
115 
116 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to);
117 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
118 static int sock_mmap(struct file *file, struct vm_area_struct *vma);
119 
120 static int sock_close(struct inode *inode, struct file *file);
121 static __poll_t sock_poll(struct file *file,
122 			      struct poll_table_struct *wait);
123 static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
124 #ifdef CONFIG_COMPAT
125 static long compat_sock_ioctl(struct file *file,
126 			      unsigned int cmd, unsigned long arg);
127 #endif
128 static int sock_fasync(int fd, struct file *filp, int on);
129 static ssize_t sock_sendpage(struct file *file, struct page *page,
130 			     int offset, size_t size, loff_t *ppos, int more);
131 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
132 				struct pipe_inode_info *pipe, size_t len,
133 				unsigned int flags);
134 
135 /*
136  *	Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
137  *	in the operation structures but are done directly via the socketcall() multiplexor.
138  */
139 
140 static const struct file_operations socket_file_ops = {
141 	.owner =	THIS_MODULE,
142 	.llseek =	no_llseek,
143 	.read_iter =	sock_read_iter,
144 	.write_iter =	sock_write_iter,
145 	.poll =		sock_poll,
146 	.unlocked_ioctl = sock_ioctl,
147 #ifdef CONFIG_COMPAT
148 	.compat_ioctl = compat_sock_ioctl,
149 #endif
150 	.mmap =		sock_mmap,
151 	.release =	sock_close,
152 	.fasync =	sock_fasync,
153 	.sendpage =	sock_sendpage,
154 	.splice_write = generic_splice_sendpage,
155 	.splice_read =	sock_splice_read,
156 };
157 
158 /*
159  *	The protocol list. Each protocol is registered in here.
160  */
161 
162 static DEFINE_SPINLOCK(net_family_lock);
163 static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
164 
165 /*
166  * Support routines.
167  * Move socket addresses back and forth across the kernel/user
168  * divide and look after the messy bits.
169  */
170 
171 /**
172  *	move_addr_to_kernel	-	copy a socket address into kernel space
173  *	@uaddr: Address in user space
174  *	@kaddr: Address in kernel space
175  *	@ulen: Length in user space
176  *
177  *	The address is copied into kernel space. If the provided address is
178  *	too long an error code of -EINVAL is returned. If the copy gives
179  *	invalid addresses -EFAULT is returned. On a success 0 is returned.
180  */
181 
182 int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
183 {
184 	if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
185 		return -EINVAL;
186 	if (ulen == 0)
187 		return 0;
188 	if (copy_from_user(kaddr, uaddr, ulen))
189 		return -EFAULT;
190 	return audit_sockaddr(ulen, kaddr);
191 }
192 
193 /**
194  *	move_addr_to_user	-	copy an address to user space
195  *	@kaddr: kernel space address
196  *	@klen: length of address in kernel
197  *	@uaddr: user space address
198  *	@ulen: pointer to user length field
199  *
200  *	The value pointed to by ulen on entry is the buffer length available.
201  *	This is overwritten with the buffer space used. -EINVAL is returned
202  *	if an overlong buffer is specified or a negative buffer size. -EFAULT
203  *	is returned if either the buffer or the length field are not
204  *	accessible.
205  *	After copying the data up to the limit the user specifies, the true
206  *	length of the data is written over the length limit the user
207  *	specified. Zero is returned for a success.
208  */
209 
210 static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
211 			     void __user *uaddr, int __user *ulen)
212 {
213 	int err;
214 	int len;
215 
216 	BUG_ON(klen > sizeof(struct sockaddr_storage));
217 	err = get_user(len, ulen);
218 	if (err)
219 		return err;
220 	if (len > klen)
221 		len = klen;
222 	if (len < 0)
223 		return -EINVAL;
224 	if (len) {
225 		if (audit_sockaddr(klen, kaddr))
226 			return -ENOMEM;
227 		if (copy_to_user(uaddr, kaddr, len))
228 			return -EFAULT;
229 	}
230 	/*
231 	 *      "fromlen shall refer to the value before truncation.."
232 	 *                      1003.1g
233 	 */
234 	return __put_user(klen, ulen);
235 }
236 
237 static struct kmem_cache *sock_inode_cachep __ro_after_init;
238 
239 static struct inode *sock_alloc_inode(struct super_block *sb)
240 {
241 	struct socket_alloc *ei;
242 	struct socket_wq *wq;
243 
244 	ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
245 	if (!ei)
246 		return NULL;
247 	wq = kmalloc(sizeof(*wq), GFP_KERNEL);
248 	if (!wq) {
249 		kmem_cache_free(sock_inode_cachep, ei);
250 		return NULL;
251 	}
252 	init_waitqueue_head(&wq->wait);
253 	wq->fasync_list = NULL;
254 	wq->flags = 0;
255 	ei->socket.wq = wq;
256 
257 	ei->socket.state = SS_UNCONNECTED;
258 	ei->socket.flags = 0;
259 	ei->socket.ops = NULL;
260 	ei->socket.sk = NULL;
261 	ei->socket.file = NULL;
262 
263 	return &ei->vfs_inode;
264 }
265 
266 static void sock_destroy_inode(struct inode *inode)
267 {
268 	struct socket_alloc *ei;
269 
270 	ei = container_of(inode, struct socket_alloc, vfs_inode);
271 	kfree_rcu(ei->socket.wq, rcu);
272 	kmem_cache_free(sock_inode_cachep, ei);
273 }
274 
275 static void init_once(void *foo)
276 {
277 	struct socket_alloc *ei = (struct socket_alloc *)foo;
278 
279 	inode_init_once(&ei->vfs_inode);
280 }
281 
282 static void init_inodecache(void)
283 {
284 	sock_inode_cachep = kmem_cache_create("sock_inode_cache",
285 					      sizeof(struct socket_alloc),
286 					      0,
287 					      (SLAB_HWCACHE_ALIGN |
288 					       SLAB_RECLAIM_ACCOUNT |
289 					       SLAB_MEM_SPREAD | SLAB_ACCOUNT),
290 					      init_once);
291 	BUG_ON(sock_inode_cachep == NULL);
292 }
293 
294 static const struct super_operations sockfs_ops = {
295 	.alloc_inode	= sock_alloc_inode,
296 	.destroy_inode	= sock_destroy_inode,
297 	.statfs		= simple_statfs,
298 };
299 
300 /*
301  * sockfs_dname() is called from d_path().
302  */
303 static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
304 {
305 	return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",
306 				d_inode(dentry)->i_ino);
307 }
308 
309 static const struct dentry_operations sockfs_dentry_operations = {
310 	.d_dname  = sockfs_dname,
311 };
312 
313 static int sockfs_xattr_get(const struct xattr_handler *handler,
314 			    struct dentry *dentry, struct inode *inode,
315 			    const char *suffix, void *value, size_t size)
316 {
317 	if (value) {
318 		if (dentry->d_name.len + 1 > size)
319 			return -ERANGE;
320 		memcpy(value, dentry->d_name.name, dentry->d_name.len + 1);
321 	}
322 	return dentry->d_name.len + 1;
323 }
324 
325 #define XATTR_SOCKPROTONAME_SUFFIX "sockprotoname"
326 #define XATTR_NAME_SOCKPROTONAME (XATTR_SYSTEM_PREFIX XATTR_SOCKPROTONAME_SUFFIX)
327 #define XATTR_NAME_SOCKPROTONAME_LEN (sizeof(XATTR_NAME_SOCKPROTONAME)-1)
328 
329 static const struct xattr_handler sockfs_xattr_handler = {
330 	.name = XATTR_NAME_SOCKPROTONAME,
331 	.get = sockfs_xattr_get,
332 };
333 
334 static int sockfs_security_xattr_set(const struct xattr_handler *handler,
335 				     struct dentry *dentry, struct inode *inode,
336 				     const char *suffix, const void *value,
337 				     size_t size, int flags)
338 {
339 	/* Handled by LSM. */
340 	return -EAGAIN;
341 }
342 
343 static const struct xattr_handler sockfs_security_xattr_handler = {
344 	.prefix = XATTR_SECURITY_PREFIX,
345 	.set = sockfs_security_xattr_set,
346 };
347 
348 static const struct xattr_handler *sockfs_xattr_handlers[] = {
349 	&sockfs_xattr_handler,
350 	&sockfs_security_xattr_handler,
351 	NULL
352 };
353 
354 static struct dentry *sockfs_mount(struct file_system_type *fs_type,
355 			 int flags, const char *dev_name, void *data)
356 {
357 	return mount_pseudo_xattr(fs_type, "socket:", &sockfs_ops,
358 				  sockfs_xattr_handlers,
359 				  &sockfs_dentry_operations, SOCKFS_MAGIC);
360 }
361 
362 static struct vfsmount *sock_mnt __read_mostly;
363 
364 static struct file_system_type sock_fs_type = {
365 	.name =		"sockfs",
366 	.mount =	sockfs_mount,
367 	.kill_sb =	kill_anon_super,
368 };
369 
370 /*
371  *	Obtains the first available file descriptor and sets it up for use.
372  *
373  *	These functions create file structures and maps them to fd space
374  *	of the current process. On success it returns file descriptor
375  *	and file struct implicitly stored in sock->file.
376  *	Note that another thread may close file descriptor before we return
377  *	from this function. We use the fact that now we do not refer
378  *	to socket after mapping. If one day we will need it, this
379  *	function will increment ref. count on file by 1.
380  *
381  *	In any case returned fd MAY BE not valid!
382  *	This race condition is unavoidable
383  *	with shared fd spaces, we cannot solve it inside kernel,
384  *	but we take care of internal coherence yet.
385  */
386 
387 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
388 {
389 	struct file *file;
390 
391 	if (!dname)
392 		dname = sock->sk ? sock->sk->sk_prot_creator->name : "";
393 
394 	file = alloc_file_pseudo(SOCK_INODE(sock), sock_mnt, dname,
395 				O_RDWR | (flags & O_NONBLOCK),
396 				&socket_file_ops);
397 	if (IS_ERR(file)) {
398 		sock_release(sock);
399 		return file;
400 	}
401 
402 	sock->file = file;
403 	file->private_data = sock;
404 	return file;
405 }
406 EXPORT_SYMBOL(sock_alloc_file);
407 
408 static int sock_map_fd(struct socket *sock, int flags)
409 {
410 	struct file *newfile;
411 	int fd = get_unused_fd_flags(flags);
412 	if (unlikely(fd < 0)) {
413 		sock_release(sock);
414 		return fd;
415 	}
416 
417 	newfile = sock_alloc_file(sock, flags, NULL);
418 	if (likely(!IS_ERR(newfile))) {
419 		fd_install(fd, newfile);
420 		return fd;
421 	}
422 
423 	put_unused_fd(fd);
424 	return PTR_ERR(newfile);
425 }
426 
427 struct socket *sock_from_file(struct file *file, int *err)
428 {
429 	if (file->f_op == &socket_file_ops)
430 		return file->private_data;	/* set in sock_map_fd */
431 
432 	*err = -ENOTSOCK;
433 	return NULL;
434 }
435 EXPORT_SYMBOL(sock_from_file);
436 
437 /**
438  *	sockfd_lookup - Go from a file number to its socket slot
439  *	@fd: file handle
440  *	@err: pointer to an error code return
441  *
442  *	The file handle passed in is locked and the socket it is bound
443  *	to is returned. If an error occurs the err pointer is overwritten
444  *	with a negative errno code and NULL is returned. The function checks
445  *	for both invalid handles and passing a handle which is not a socket.
446  *
447  *	On a success the socket object pointer is returned.
448  */
449 
450 struct socket *sockfd_lookup(int fd, int *err)
451 {
452 	struct file *file;
453 	struct socket *sock;
454 
455 	file = fget(fd);
456 	if (!file) {
457 		*err = -EBADF;
458 		return NULL;
459 	}
460 
461 	sock = sock_from_file(file, err);
462 	if (!sock)
463 		fput(file);
464 	return sock;
465 }
466 EXPORT_SYMBOL(sockfd_lookup);
467 
468 static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
469 {
470 	struct fd f = fdget(fd);
471 	struct socket *sock;
472 
473 	*err = -EBADF;
474 	if (f.file) {
475 		sock = sock_from_file(f.file, err);
476 		if (likely(sock)) {
477 			*fput_needed = f.flags;
478 			return sock;
479 		}
480 		fdput(f);
481 	}
482 	return NULL;
483 }
484 
485 static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
486 				size_t size)
487 {
488 	ssize_t len;
489 	ssize_t used = 0;
490 
491 	len = security_inode_listsecurity(d_inode(dentry), buffer, size);
492 	if (len < 0)
493 		return len;
494 	used += len;
495 	if (buffer) {
496 		if (size < used)
497 			return -ERANGE;
498 		buffer += len;
499 	}
500 
501 	len = (XATTR_NAME_SOCKPROTONAME_LEN + 1);
502 	used += len;
503 	if (buffer) {
504 		if (size < used)
505 			return -ERANGE;
506 		memcpy(buffer, XATTR_NAME_SOCKPROTONAME, len);
507 		buffer += len;
508 	}
509 
510 	return used;
511 }
512 
513 static int sockfs_setattr(struct dentry *dentry, struct iattr *iattr)
514 {
515 	int err = simple_setattr(dentry, iattr);
516 
517 	if (!err && (iattr->ia_valid & ATTR_UID)) {
518 		struct socket *sock = SOCKET_I(d_inode(dentry));
519 
520 		if (sock->sk)
521 			sock->sk->sk_uid = iattr->ia_uid;
522 		else
523 			err = -ENOENT;
524 	}
525 
526 	return err;
527 }
528 
529 static const struct inode_operations sockfs_inode_ops = {
530 	.listxattr = sockfs_listxattr,
531 	.setattr = sockfs_setattr,
532 };
533 
534 /**
535  *	sock_alloc	-	allocate a socket
536  *
537  *	Allocate a new inode and socket object. The two are bound together
538  *	and initialised. The socket is then returned. If we are out of inodes
539  *	NULL is returned.
540  */
541 
542 struct socket *sock_alloc(void)
543 {
544 	struct inode *inode;
545 	struct socket *sock;
546 
547 	inode = new_inode_pseudo(sock_mnt->mnt_sb);
548 	if (!inode)
549 		return NULL;
550 
551 	sock = SOCKET_I(inode);
552 
553 	inode->i_ino = get_next_ino();
554 	inode->i_mode = S_IFSOCK | S_IRWXUGO;
555 	inode->i_uid = current_fsuid();
556 	inode->i_gid = current_fsgid();
557 	inode->i_op = &sockfs_inode_ops;
558 
559 	return sock;
560 }
561 EXPORT_SYMBOL(sock_alloc);
562 
563 /**
564  *	sock_release	-	close a socket
565  *	@sock: socket to close
566  *
567  *	The socket is released from the protocol stack if it has a release
568  *	callback, and the inode is then released if the socket is bound to
569  *	an inode not a file.
570  */
571 
572 static void __sock_release(struct socket *sock, struct inode *inode)
573 {
574 	if (sock->ops) {
575 		struct module *owner = sock->ops->owner;
576 
577 		if (inode)
578 			inode_lock(inode);
579 		sock->ops->release(sock);
580 		if (inode)
581 			inode_unlock(inode);
582 		sock->ops = NULL;
583 		module_put(owner);
584 	}
585 
586 	if (sock->wq->fasync_list)
587 		pr_err("%s: fasync list not empty!\n", __func__);
588 
589 	if (!sock->file) {
590 		iput(SOCK_INODE(sock));
591 		return;
592 	}
593 	sock->file = NULL;
594 }
595 
596 void sock_release(struct socket *sock)
597 {
598 	__sock_release(sock, NULL);
599 }
600 EXPORT_SYMBOL(sock_release);
601 
602 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
603 {
604 	u8 flags = *tx_flags;
605 
606 	if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE)
607 		flags |= SKBTX_HW_TSTAMP;
608 
609 	if (tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)
610 		flags |= SKBTX_SW_TSTAMP;
611 
612 	if (tsflags & SOF_TIMESTAMPING_TX_SCHED)
613 		flags |= SKBTX_SCHED_TSTAMP;
614 
615 	*tx_flags = flags;
616 }
617 EXPORT_SYMBOL(__sock_tx_timestamp);
618 
619 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
620 {
621 	int ret = sock->ops->sendmsg(sock, msg, msg_data_left(msg));
622 	BUG_ON(ret == -EIOCBQUEUED);
623 	return ret;
624 }
625 
626 int sock_sendmsg(struct socket *sock, struct msghdr *msg)
627 {
628 	int err = security_socket_sendmsg(sock, msg,
629 					  msg_data_left(msg));
630 
631 	return err ?: sock_sendmsg_nosec(sock, msg);
632 }
633 EXPORT_SYMBOL(sock_sendmsg);
634 
635 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
636 		   struct kvec *vec, size_t num, size_t size)
637 {
638 	iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
639 	return sock_sendmsg(sock, msg);
640 }
641 EXPORT_SYMBOL(kernel_sendmsg);
642 
643 int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
644 			  struct kvec *vec, size_t num, size_t size)
645 {
646 	struct socket *sock = sk->sk_socket;
647 
648 	if (!sock->ops->sendmsg_locked)
649 		return sock_no_sendmsg_locked(sk, msg, size);
650 
651 	iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
652 
653 	return sock->ops->sendmsg_locked(sk, msg, msg_data_left(msg));
654 }
655 EXPORT_SYMBOL(kernel_sendmsg_locked);
656 
657 static bool skb_is_err_queue(const struct sk_buff *skb)
658 {
659 	/* pkt_type of skbs enqueued on the error queue are set to
660 	 * PACKET_OUTGOING in skb_set_err_queue(). This is only safe to do
661 	 * in recvmsg, since skbs received on a local socket will never
662 	 * have a pkt_type of PACKET_OUTGOING.
663 	 */
664 	return skb->pkt_type == PACKET_OUTGOING;
665 }
666 
667 /* On transmit, software and hardware timestamps are returned independently.
668  * As the two skb clones share the hardware timestamp, which may be updated
669  * before the software timestamp is received, a hardware TX timestamp may be
670  * returned only if there is no software TX timestamp. Ignore false software
671  * timestamps, which may be made in the __sock_recv_timestamp() call when the
672  * option SO_TIMESTAMP(NS) is enabled on the socket, even when the skb has a
673  * hardware timestamp.
674  */
675 static bool skb_is_swtx_tstamp(const struct sk_buff *skb, int false_tstamp)
676 {
677 	return skb->tstamp && !false_tstamp && skb_is_err_queue(skb);
678 }
679 
680 static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb)
681 {
682 	struct scm_ts_pktinfo ts_pktinfo;
683 	struct net_device *orig_dev;
684 
685 	if (!skb_mac_header_was_set(skb))
686 		return;
687 
688 	memset(&ts_pktinfo, 0, sizeof(ts_pktinfo));
689 
690 	rcu_read_lock();
691 	orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
692 	if (orig_dev)
693 		ts_pktinfo.if_index = orig_dev->ifindex;
694 	rcu_read_unlock();
695 
696 	ts_pktinfo.pkt_length = skb->len - skb_mac_offset(skb);
697 	put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
698 		 sizeof(ts_pktinfo), &ts_pktinfo);
699 }
700 
701 /*
702  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
703  */
704 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
705 	struct sk_buff *skb)
706 {
707 	int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
708 	struct scm_timestamping tss;
709 	int empty = 1, false_tstamp = 0;
710 	struct skb_shared_hwtstamps *shhwtstamps =
711 		skb_hwtstamps(skb);
712 
713 	/* Race occurred between timestamp enabling and packet
714 	   receiving.  Fill in the current time for now. */
715 	if (need_software_tstamp && skb->tstamp == 0) {
716 		__net_timestamp(skb);
717 		false_tstamp = 1;
718 	}
719 
720 	if (need_software_tstamp) {
721 		if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
722 			struct timeval tv;
723 			skb_get_timestamp(skb, &tv);
724 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP,
725 				 sizeof(tv), &tv);
726 		} else {
727 			struct timespec ts;
728 			skb_get_timestampns(skb, &ts);
729 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPNS,
730 				 sizeof(ts), &ts);
731 		}
732 	}
733 
734 	memset(&tss, 0, sizeof(tss));
735 	if ((sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
736 	    ktime_to_timespec_cond(skb->tstamp, tss.ts + 0))
737 		empty = 0;
738 	if (shhwtstamps &&
739 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
740 	    !skb_is_swtx_tstamp(skb, false_tstamp) &&
741 	    ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2)) {
742 		empty = 0;
743 		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
744 		    !skb_is_err_queue(skb))
745 			put_ts_pktinfo(msg, skb);
746 	}
747 	if (!empty) {
748 		put_cmsg(msg, SOL_SOCKET,
749 			 SCM_TIMESTAMPING, sizeof(tss), &tss);
750 
751 		if (skb_is_err_queue(skb) && skb->len &&
752 		    SKB_EXT_ERR(skb)->opt_stats)
753 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS,
754 				 skb->len, skb->data);
755 	}
756 }
757 EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
758 
759 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
760 	struct sk_buff *skb)
761 {
762 	int ack;
763 
764 	if (!sock_flag(sk, SOCK_WIFI_STATUS))
765 		return;
766 	if (!skb->wifi_acked_valid)
767 		return;
768 
769 	ack = skb->wifi_acked;
770 
771 	put_cmsg(msg, SOL_SOCKET, SCM_WIFI_STATUS, sizeof(ack), &ack);
772 }
773 EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
774 
775 static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
776 				   struct sk_buff *skb)
777 {
778 	if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
779 		put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
780 			sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
781 }
782 
783 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
784 	struct sk_buff *skb)
785 {
786 	sock_recv_timestamp(msg, sk, skb);
787 	sock_recv_drops(msg, sk, skb);
788 }
789 EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops);
790 
791 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
792 				     int flags)
793 {
794 	return sock->ops->recvmsg(sock, msg, msg_data_left(msg), flags);
795 }
796 
797 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
798 {
799 	int err = security_socket_recvmsg(sock, msg, msg_data_left(msg), flags);
800 
801 	return err ?: sock_recvmsg_nosec(sock, msg, flags);
802 }
803 EXPORT_SYMBOL(sock_recvmsg);
804 
805 /**
806  * kernel_recvmsg - Receive a message from a socket (kernel space)
807  * @sock:       The socket to receive the message from
808  * @msg:        Received message
809  * @vec:        Input s/g array for message data
810  * @num:        Size of input s/g array
811  * @size:       Number of bytes to read
812  * @flags:      Message flags (MSG_DONTWAIT, etc...)
813  *
814  * On return the msg structure contains the scatter/gather array passed in the
815  * vec argument. The array is modified so that it consists of the unfilled
816  * portion of the original array.
817  *
818  * The returned value is the total number of bytes received, or an error.
819  */
820 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
821 		   struct kvec *vec, size_t num, size_t size, int flags)
822 {
823 	mm_segment_t oldfs = get_fs();
824 	int result;
825 
826 	iov_iter_kvec(&msg->msg_iter, READ | ITER_KVEC, vec, num, size);
827 	set_fs(KERNEL_DS);
828 	result = sock_recvmsg(sock, msg, flags);
829 	set_fs(oldfs);
830 	return result;
831 }
832 EXPORT_SYMBOL(kernel_recvmsg);
833 
834 static ssize_t sock_sendpage(struct file *file, struct page *page,
835 			     int offset, size_t size, loff_t *ppos, int more)
836 {
837 	struct socket *sock;
838 	int flags;
839 
840 	sock = file->private_data;
841 
842 	flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
843 	/* more is a combination of MSG_MORE and MSG_SENDPAGE_NOTLAST */
844 	flags |= more;
845 
846 	return kernel_sendpage(sock, page, offset, size, flags);
847 }
848 
849 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
850 				struct pipe_inode_info *pipe, size_t len,
851 				unsigned int flags)
852 {
853 	struct socket *sock = file->private_data;
854 
855 	if (unlikely(!sock->ops->splice_read))
856 		return -EINVAL;
857 
858 	return sock->ops->splice_read(sock, ppos, pipe, len, flags);
859 }
860 
861 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
862 {
863 	struct file *file = iocb->ki_filp;
864 	struct socket *sock = file->private_data;
865 	struct msghdr msg = {.msg_iter = *to,
866 			     .msg_iocb = iocb};
867 	ssize_t res;
868 
869 	if (file->f_flags & O_NONBLOCK)
870 		msg.msg_flags = MSG_DONTWAIT;
871 
872 	if (iocb->ki_pos != 0)
873 		return -ESPIPE;
874 
875 	if (!iov_iter_count(to))	/* Match SYS5 behaviour */
876 		return 0;
877 
878 	res = sock_recvmsg(sock, &msg, msg.msg_flags);
879 	*to = msg.msg_iter;
880 	return res;
881 }
882 
883 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
884 {
885 	struct file *file = iocb->ki_filp;
886 	struct socket *sock = file->private_data;
887 	struct msghdr msg = {.msg_iter = *from,
888 			     .msg_iocb = iocb};
889 	ssize_t res;
890 
891 	if (iocb->ki_pos != 0)
892 		return -ESPIPE;
893 
894 	if (file->f_flags & O_NONBLOCK)
895 		msg.msg_flags = MSG_DONTWAIT;
896 
897 	if (sock->type == SOCK_SEQPACKET)
898 		msg.msg_flags |= MSG_EOR;
899 
900 	res = sock_sendmsg(sock, &msg);
901 	*from = msg.msg_iter;
902 	return res;
903 }
904 
905 /*
906  * Atomic setting of ioctl hooks to avoid race
907  * with module unload.
908  */
909 
910 static DEFINE_MUTEX(br_ioctl_mutex);
911 static int (*br_ioctl_hook) (struct net *, unsigned int cmd, void __user *arg);
912 
913 void brioctl_set(int (*hook) (struct net *, unsigned int, void __user *))
914 {
915 	mutex_lock(&br_ioctl_mutex);
916 	br_ioctl_hook = hook;
917 	mutex_unlock(&br_ioctl_mutex);
918 }
919 EXPORT_SYMBOL(brioctl_set);
920 
921 static DEFINE_MUTEX(vlan_ioctl_mutex);
922 static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
923 
924 void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
925 {
926 	mutex_lock(&vlan_ioctl_mutex);
927 	vlan_ioctl_hook = hook;
928 	mutex_unlock(&vlan_ioctl_mutex);
929 }
930 EXPORT_SYMBOL(vlan_ioctl_set);
931 
932 static DEFINE_MUTEX(dlci_ioctl_mutex);
933 static int (*dlci_ioctl_hook) (unsigned int, void __user *);
934 
935 void dlci_ioctl_set(int (*hook) (unsigned int, void __user *))
936 {
937 	mutex_lock(&dlci_ioctl_mutex);
938 	dlci_ioctl_hook = hook;
939 	mutex_unlock(&dlci_ioctl_mutex);
940 }
941 EXPORT_SYMBOL(dlci_ioctl_set);
942 
943 static long sock_do_ioctl(struct net *net, struct socket *sock,
944 				 unsigned int cmd, unsigned long arg)
945 {
946 	int err;
947 	void __user *argp = (void __user *)arg;
948 
949 	err = sock->ops->ioctl(sock, cmd, arg);
950 
951 	/*
952 	 * If this ioctl is unknown try to hand it down
953 	 * to the NIC driver.
954 	 */
955 	if (err != -ENOIOCTLCMD)
956 		return err;
957 
958 	if (cmd == SIOCGIFCONF) {
959 		struct ifconf ifc;
960 		if (copy_from_user(&ifc, argp, sizeof(struct ifconf)))
961 			return -EFAULT;
962 		rtnl_lock();
963 		err = dev_ifconf(net, &ifc, sizeof(struct ifreq));
964 		rtnl_unlock();
965 		if (!err && copy_to_user(argp, &ifc, sizeof(struct ifconf)))
966 			err = -EFAULT;
967 	} else {
968 		struct ifreq ifr;
969 		bool need_copyout;
970 		if (copy_from_user(&ifr, argp, sizeof(struct ifreq)))
971 			return -EFAULT;
972 		err = dev_ioctl(net, cmd, &ifr, &need_copyout);
973 		if (!err && need_copyout)
974 			if (copy_to_user(argp, &ifr, sizeof(struct ifreq)))
975 				return -EFAULT;
976 	}
977 	return err;
978 }
979 
980 /*
981  *	With an ioctl, arg may well be a user mode pointer, but we don't know
982  *	what to do with it - that's up to the protocol still.
983  */
984 
985 struct ns_common *get_net_ns(struct ns_common *ns)
986 {
987 	return &get_net(container_of(ns, struct net, ns))->ns;
988 }
989 EXPORT_SYMBOL_GPL(get_net_ns);
990 
991 static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
992 {
993 	struct socket *sock;
994 	struct sock *sk;
995 	void __user *argp = (void __user *)arg;
996 	int pid, err;
997 	struct net *net;
998 
999 	sock = file->private_data;
1000 	sk = sock->sk;
1001 	net = sock_net(sk);
1002 	if (unlikely(cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))) {
1003 		struct ifreq ifr;
1004 		bool need_copyout;
1005 		if (copy_from_user(&ifr, argp, sizeof(struct ifreq)))
1006 			return -EFAULT;
1007 		err = dev_ioctl(net, cmd, &ifr, &need_copyout);
1008 		if (!err && need_copyout)
1009 			if (copy_to_user(argp, &ifr, sizeof(struct ifreq)))
1010 				return -EFAULT;
1011 	} else
1012 #ifdef CONFIG_WEXT_CORE
1013 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
1014 		err = wext_handle_ioctl(net, cmd, argp);
1015 	} else
1016 #endif
1017 		switch (cmd) {
1018 		case FIOSETOWN:
1019 		case SIOCSPGRP:
1020 			err = -EFAULT;
1021 			if (get_user(pid, (int __user *)argp))
1022 				break;
1023 			err = f_setown(sock->file, pid, 1);
1024 			break;
1025 		case FIOGETOWN:
1026 		case SIOCGPGRP:
1027 			err = put_user(f_getown(sock->file),
1028 				       (int __user *)argp);
1029 			break;
1030 		case SIOCGIFBR:
1031 		case SIOCSIFBR:
1032 		case SIOCBRADDBR:
1033 		case SIOCBRDELBR:
1034 			err = -ENOPKG;
1035 			if (!br_ioctl_hook)
1036 				request_module("bridge");
1037 
1038 			mutex_lock(&br_ioctl_mutex);
1039 			if (br_ioctl_hook)
1040 				err = br_ioctl_hook(net, cmd, argp);
1041 			mutex_unlock(&br_ioctl_mutex);
1042 			break;
1043 		case SIOCGIFVLAN:
1044 		case SIOCSIFVLAN:
1045 			err = -ENOPKG;
1046 			if (!vlan_ioctl_hook)
1047 				request_module("8021q");
1048 
1049 			mutex_lock(&vlan_ioctl_mutex);
1050 			if (vlan_ioctl_hook)
1051 				err = vlan_ioctl_hook(net, argp);
1052 			mutex_unlock(&vlan_ioctl_mutex);
1053 			break;
1054 		case SIOCADDDLCI:
1055 		case SIOCDELDLCI:
1056 			err = -ENOPKG;
1057 			if (!dlci_ioctl_hook)
1058 				request_module("dlci");
1059 
1060 			mutex_lock(&dlci_ioctl_mutex);
1061 			if (dlci_ioctl_hook)
1062 				err = dlci_ioctl_hook(cmd, argp);
1063 			mutex_unlock(&dlci_ioctl_mutex);
1064 			break;
1065 		case SIOCGSKNS:
1066 			err = -EPERM;
1067 			if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1068 				break;
1069 
1070 			err = open_related_ns(&net->ns, get_net_ns);
1071 			break;
1072 		default:
1073 			err = sock_do_ioctl(net, sock, cmd, arg);
1074 			break;
1075 		}
1076 	return err;
1077 }
1078 
1079 int sock_create_lite(int family, int type, int protocol, struct socket **res)
1080 {
1081 	int err;
1082 	struct socket *sock = NULL;
1083 
1084 	err = security_socket_create(family, type, protocol, 1);
1085 	if (err)
1086 		goto out;
1087 
1088 	sock = sock_alloc();
1089 	if (!sock) {
1090 		err = -ENOMEM;
1091 		goto out;
1092 	}
1093 
1094 	sock->type = type;
1095 	err = security_socket_post_create(sock, family, type, protocol, 1);
1096 	if (err)
1097 		goto out_release;
1098 
1099 out:
1100 	*res = sock;
1101 	return err;
1102 out_release:
1103 	sock_release(sock);
1104 	sock = NULL;
1105 	goto out;
1106 }
1107 EXPORT_SYMBOL(sock_create_lite);
1108 
1109 /* No kernel lock held - perfect */
1110 static __poll_t sock_poll(struct file *file, poll_table *wait)
1111 {
1112 	struct socket *sock = file->private_data;
1113 	__poll_t events = poll_requested_events(wait), flag = 0;
1114 
1115 	if (!sock->ops->poll)
1116 		return 0;
1117 
1118 	if (sk_can_busy_loop(sock->sk)) {
1119 		/* poll once if requested by the syscall */
1120 		if (events & POLL_BUSY_LOOP)
1121 			sk_busy_loop(sock->sk, 1);
1122 
1123 		/* if this socket can poll_ll, tell the system call */
1124 		flag = POLL_BUSY_LOOP;
1125 	}
1126 
1127 	return sock->ops->poll(file, sock, wait) | flag;
1128 }
1129 
1130 static int sock_mmap(struct file *file, struct vm_area_struct *vma)
1131 {
1132 	struct socket *sock = file->private_data;
1133 
1134 	return sock->ops->mmap(file, sock, vma);
1135 }
1136 
1137 static int sock_close(struct inode *inode, struct file *filp)
1138 {
1139 	__sock_release(SOCKET_I(inode), inode);
1140 	return 0;
1141 }
1142 
1143 /*
1144  *	Update the socket async list
1145  *
1146  *	Fasync_list locking strategy.
1147  *
1148  *	1. fasync_list is modified only under process context socket lock
1149  *	   i.e. under semaphore.
1150  *	2. fasync_list is used under read_lock(&sk->sk_callback_lock)
1151  *	   or under socket lock
1152  */
1153 
1154 static int sock_fasync(int fd, struct file *filp, int on)
1155 {
1156 	struct socket *sock = filp->private_data;
1157 	struct sock *sk = sock->sk;
1158 	struct socket_wq *wq;
1159 
1160 	if (sk == NULL)
1161 		return -EINVAL;
1162 
1163 	lock_sock(sk);
1164 	wq = sock->wq;
1165 	fasync_helper(fd, filp, on, &wq->fasync_list);
1166 
1167 	if (!wq->fasync_list)
1168 		sock_reset_flag(sk, SOCK_FASYNC);
1169 	else
1170 		sock_set_flag(sk, SOCK_FASYNC);
1171 
1172 	release_sock(sk);
1173 	return 0;
1174 }
1175 
1176 /* This function may be called only under rcu_lock */
1177 
1178 int sock_wake_async(struct socket_wq *wq, int how, int band)
1179 {
1180 	if (!wq || !wq->fasync_list)
1181 		return -1;
1182 
1183 	switch (how) {
1184 	case SOCK_WAKE_WAITD:
1185 		if (test_bit(SOCKWQ_ASYNC_WAITDATA, &wq->flags))
1186 			break;
1187 		goto call_kill;
1188 	case SOCK_WAKE_SPACE:
1189 		if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags))
1190 			break;
1191 		/* fall through */
1192 	case SOCK_WAKE_IO:
1193 call_kill:
1194 		kill_fasync(&wq->fasync_list, SIGIO, band);
1195 		break;
1196 	case SOCK_WAKE_URG:
1197 		kill_fasync(&wq->fasync_list, SIGURG, band);
1198 	}
1199 
1200 	return 0;
1201 }
1202 EXPORT_SYMBOL(sock_wake_async);
1203 
1204 int __sock_create(struct net *net, int family, int type, int protocol,
1205 			 struct socket **res, int kern)
1206 {
1207 	int err;
1208 	struct socket *sock;
1209 	const struct net_proto_family *pf;
1210 
1211 	/*
1212 	 *      Check protocol is in range
1213 	 */
1214 	if (family < 0 || family >= NPROTO)
1215 		return -EAFNOSUPPORT;
1216 	if (type < 0 || type >= SOCK_MAX)
1217 		return -EINVAL;
1218 
1219 	/* Compatibility.
1220 
1221 	   This uglymoron is moved from INET layer to here to avoid
1222 	   deadlock in module load.
1223 	 */
1224 	if (family == PF_INET && type == SOCK_PACKET) {
1225 		pr_info_once("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
1226 			     current->comm);
1227 		family = PF_PACKET;
1228 	}
1229 
1230 	err = security_socket_create(family, type, protocol, kern);
1231 	if (err)
1232 		return err;
1233 
1234 	/*
1235 	 *	Allocate the socket and allow the family to set things up. if
1236 	 *	the protocol is 0, the family is instructed to select an appropriate
1237 	 *	default.
1238 	 */
1239 	sock = sock_alloc();
1240 	if (!sock) {
1241 		net_warn_ratelimited("socket: no more sockets\n");
1242 		return -ENFILE;	/* Not exactly a match, but its the
1243 				   closest posix thing */
1244 	}
1245 
1246 	sock->type = type;
1247 
1248 #ifdef CONFIG_MODULES
1249 	/* Attempt to load a protocol module if the find failed.
1250 	 *
1251 	 * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
1252 	 * requested real, full-featured networking support upon configuration.
1253 	 * Otherwise module support will break!
1254 	 */
1255 	if (rcu_access_pointer(net_families[family]) == NULL)
1256 		request_module("net-pf-%d", family);
1257 #endif
1258 
1259 	rcu_read_lock();
1260 	pf = rcu_dereference(net_families[family]);
1261 	err = -EAFNOSUPPORT;
1262 	if (!pf)
1263 		goto out_release;
1264 
1265 	/*
1266 	 * We will call the ->create function, that possibly is in a loadable
1267 	 * module, so we have to bump that loadable module refcnt first.
1268 	 */
1269 	if (!try_module_get(pf->owner))
1270 		goto out_release;
1271 
1272 	/* Now protected by module ref count */
1273 	rcu_read_unlock();
1274 
1275 	err = pf->create(net, sock, protocol, kern);
1276 	if (err < 0)
1277 		goto out_module_put;
1278 
1279 	/*
1280 	 * Now to bump the refcnt of the [loadable] module that owns this
1281 	 * socket at sock_release time we decrement its refcnt.
1282 	 */
1283 	if (!try_module_get(sock->ops->owner))
1284 		goto out_module_busy;
1285 
1286 	/*
1287 	 * Now that we're done with the ->create function, the [loadable]
1288 	 * module can have its refcnt decremented
1289 	 */
1290 	module_put(pf->owner);
1291 	err = security_socket_post_create(sock, family, type, protocol, kern);
1292 	if (err)
1293 		goto out_sock_release;
1294 	*res = sock;
1295 
1296 	return 0;
1297 
1298 out_module_busy:
1299 	err = -EAFNOSUPPORT;
1300 out_module_put:
1301 	sock->ops = NULL;
1302 	module_put(pf->owner);
1303 out_sock_release:
1304 	sock_release(sock);
1305 	return err;
1306 
1307 out_release:
1308 	rcu_read_unlock();
1309 	goto out_sock_release;
1310 }
1311 EXPORT_SYMBOL(__sock_create);
1312 
1313 int sock_create(int family, int type, int protocol, struct socket **res)
1314 {
1315 	return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
1316 }
1317 EXPORT_SYMBOL(sock_create);
1318 
1319 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
1320 {
1321 	return __sock_create(net, family, type, protocol, res, 1);
1322 }
1323 EXPORT_SYMBOL(sock_create_kern);
1324 
1325 int __sys_socket(int family, int type, int protocol)
1326 {
1327 	int retval;
1328 	struct socket *sock;
1329 	int flags;
1330 
1331 	/* Check the SOCK_* constants for consistency.  */
1332 	BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
1333 	BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
1334 	BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
1335 	BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
1336 
1337 	flags = type & ~SOCK_TYPE_MASK;
1338 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1339 		return -EINVAL;
1340 	type &= SOCK_TYPE_MASK;
1341 
1342 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1343 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1344 
1345 	retval = sock_create(family, type, protocol, &sock);
1346 	if (retval < 0)
1347 		return retval;
1348 
1349 	return sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
1350 }
1351 
1352 SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
1353 {
1354 	return __sys_socket(family, type, protocol);
1355 }
1356 
1357 /*
1358  *	Create a pair of connected sockets.
1359  */
1360 
1361 int __sys_socketpair(int family, int type, int protocol, int __user *usockvec)
1362 {
1363 	struct socket *sock1, *sock2;
1364 	int fd1, fd2, err;
1365 	struct file *newfile1, *newfile2;
1366 	int flags;
1367 
1368 	flags = type & ~SOCK_TYPE_MASK;
1369 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1370 		return -EINVAL;
1371 	type &= SOCK_TYPE_MASK;
1372 
1373 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1374 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1375 
1376 	/*
1377 	 * reserve descriptors and make sure we won't fail
1378 	 * to return them to userland.
1379 	 */
1380 	fd1 = get_unused_fd_flags(flags);
1381 	if (unlikely(fd1 < 0))
1382 		return fd1;
1383 
1384 	fd2 = get_unused_fd_flags(flags);
1385 	if (unlikely(fd2 < 0)) {
1386 		put_unused_fd(fd1);
1387 		return fd2;
1388 	}
1389 
1390 	err = put_user(fd1, &usockvec[0]);
1391 	if (err)
1392 		goto out;
1393 
1394 	err = put_user(fd2, &usockvec[1]);
1395 	if (err)
1396 		goto out;
1397 
1398 	/*
1399 	 * Obtain the first socket and check if the underlying protocol
1400 	 * supports the socketpair call.
1401 	 */
1402 
1403 	err = sock_create(family, type, protocol, &sock1);
1404 	if (unlikely(err < 0))
1405 		goto out;
1406 
1407 	err = sock_create(family, type, protocol, &sock2);
1408 	if (unlikely(err < 0)) {
1409 		sock_release(sock1);
1410 		goto out;
1411 	}
1412 
1413 	err = security_socket_socketpair(sock1, sock2);
1414 	if (unlikely(err)) {
1415 		sock_release(sock2);
1416 		sock_release(sock1);
1417 		goto out;
1418 	}
1419 
1420 	err = sock1->ops->socketpair(sock1, sock2);
1421 	if (unlikely(err < 0)) {
1422 		sock_release(sock2);
1423 		sock_release(sock1);
1424 		goto out;
1425 	}
1426 
1427 	newfile1 = sock_alloc_file(sock1, flags, NULL);
1428 	if (IS_ERR(newfile1)) {
1429 		err = PTR_ERR(newfile1);
1430 		sock_release(sock2);
1431 		goto out;
1432 	}
1433 
1434 	newfile2 = sock_alloc_file(sock2, flags, NULL);
1435 	if (IS_ERR(newfile2)) {
1436 		err = PTR_ERR(newfile2);
1437 		fput(newfile1);
1438 		goto out;
1439 	}
1440 
1441 	audit_fd_pair(fd1, fd2);
1442 
1443 	fd_install(fd1, newfile1);
1444 	fd_install(fd2, newfile2);
1445 	return 0;
1446 
1447 out:
1448 	put_unused_fd(fd2);
1449 	put_unused_fd(fd1);
1450 	return err;
1451 }
1452 
1453 SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
1454 		int __user *, usockvec)
1455 {
1456 	return __sys_socketpair(family, type, protocol, usockvec);
1457 }
1458 
1459 /*
1460  *	Bind a name to a socket. Nothing much to do here since it's
1461  *	the protocol's responsibility to handle the local address.
1462  *
1463  *	We move the socket address to kernel space before we call
1464  *	the protocol layer (having also checked the address is ok).
1465  */
1466 
1467 int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
1468 {
1469 	struct socket *sock;
1470 	struct sockaddr_storage address;
1471 	int err, fput_needed;
1472 
1473 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1474 	if (sock) {
1475 		err = move_addr_to_kernel(umyaddr, addrlen, &address);
1476 		if (err >= 0) {
1477 			err = security_socket_bind(sock,
1478 						   (struct sockaddr *)&address,
1479 						   addrlen);
1480 			if (!err)
1481 				err = sock->ops->bind(sock,
1482 						      (struct sockaddr *)
1483 						      &address, addrlen);
1484 		}
1485 		fput_light(sock->file, fput_needed);
1486 	}
1487 	return err;
1488 }
1489 
1490 SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
1491 {
1492 	return __sys_bind(fd, umyaddr, addrlen);
1493 }
1494 
1495 /*
1496  *	Perform a listen. Basically, we allow the protocol to do anything
1497  *	necessary for a listen, and if that works, we mark the socket as
1498  *	ready for listening.
1499  */
1500 
1501 int __sys_listen(int fd, int backlog)
1502 {
1503 	struct socket *sock;
1504 	int err, fput_needed;
1505 	int somaxconn;
1506 
1507 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1508 	if (sock) {
1509 		somaxconn = sock_net(sock->sk)->core.sysctl_somaxconn;
1510 		if ((unsigned int)backlog > somaxconn)
1511 			backlog = somaxconn;
1512 
1513 		err = security_socket_listen(sock, backlog);
1514 		if (!err)
1515 			err = sock->ops->listen(sock, backlog);
1516 
1517 		fput_light(sock->file, fput_needed);
1518 	}
1519 	return err;
1520 }
1521 
1522 SYSCALL_DEFINE2(listen, int, fd, int, backlog)
1523 {
1524 	return __sys_listen(fd, backlog);
1525 }
1526 
1527 /*
1528  *	For accept, we attempt to create a new socket, set up the link
1529  *	with the client, wake up the client, then return the new
1530  *	connected fd. We collect the address of the connector in kernel
1531  *	space and move it to user at the very end. This is unclean because
1532  *	we open the socket then return an error.
1533  *
1534  *	1003.1g adds the ability to recvmsg() to query connection pending
1535  *	status to recvmsg. We need to add that support in a way thats
1536  *	clean when we restructure accept also.
1537  */
1538 
1539 int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
1540 		  int __user *upeer_addrlen, int flags)
1541 {
1542 	struct socket *sock, *newsock;
1543 	struct file *newfile;
1544 	int err, len, newfd, fput_needed;
1545 	struct sockaddr_storage address;
1546 
1547 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1548 		return -EINVAL;
1549 
1550 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1551 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1552 
1553 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1554 	if (!sock)
1555 		goto out;
1556 
1557 	err = -ENFILE;
1558 	newsock = sock_alloc();
1559 	if (!newsock)
1560 		goto out_put;
1561 
1562 	newsock->type = sock->type;
1563 	newsock->ops = sock->ops;
1564 
1565 	/*
1566 	 * We don't need try_module_get here, as the listening socket (sock)
1567 	 * has the protocol module (sock->ops->owner) held.
1568 	 */
1569 	__module_get(newsock->ops->owner);
1570 
1571 	newfd = get_unused_fd_flags(flags);
1572 	if (unlikely(newfd < 0)) {
1573 		err = newfd;
1574 		sock_release(newsock);
1575 		goto out_put;
1576 	}
1577 	newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);
1578 	if (IS_ERR(newfile)) {
1579 		err = PTR_ERR(newfile);
1580 		put_unused_fd(newfd);
1581 		goto out_put;
1582 	}
1583 
1584 	err = security_socket_accept(sock, newsock);
1585 	if (err)
1586 		goto out_fd;
1587 
1588 	err = sock->ops->accept(sock, newsock, sock->file->f_flags, false);
1589 	if (err < 0)
1590 		goto out_fd;
1591 
1592 	if (upeer_sockaddr) {
1593 		len = newsock->ops->getname(newsock,
1594 					(struct sockaddr *)&address, 2);
1595 		if (len < 0) {
1596 			err = -ECONNABORTED;
1597 			goto out_fd;
1598 		}
1599 		err = move_addr_to_user(&address,
1600 					len, upeer_sockaddr, upeer_addrlen);
1601 		if (err < 0)
1602 			goto out_fd;
1603 	}
1604 
1605 	/* File flags are not inherited via accept() unlike another OSes. */
1606 
1607 	fd_install(newfd, newfile);
1608 	err = newfd;
1609 
1610 out_put:
1611 	fput_light(sock->file, fput_needed);
1612 out:
1613 	return err;
1614 out_fd:
1615 	fput(newfile);
1616 	put_unused_fd(newfd);
1617 	goto out_put;
1618 }
1619 
1620 SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
1621 		int __user *, upeer_addrlen, int, flags)
1622 {
1623 	return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, flags);
1624 }
1625 
1626 SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
1627 		int __user *, upeer_addrlen)
1628 {
1629 	return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
1630 }
1631 
1632 /*
1633  *	Attempt to connect to a socket with the server address.  The address
1634  *	is in user space so we verify it is OK and move it to kernel space.
1635  *
1636  *	For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
1637  *	break bindings
1638  *
1639  *	NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
1640  *	other SEQPACKET protocols that take time to connect() as it doesn't
1641  *	include the -EINPROGRESS status for such sockets.
1642  */
1643 
1644 int __sys_connect(int fd, struct sockaddr __user *uservaddr, int addrlen)
1645 {
1646 	struct socket *sock;
1647 	struct sockaddr_storage address;
1648 	int err, fput_needed;
1649 
1650 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1651 	if (!sock)
1652 		goto out;
1653 	err = move_addr_to_kernel(uservaddr, addrlen, &address);
1654 	if (err < 0)
1655 		goto out_put;
1656 
1657 	err =
1658 	    security_socket_connect(sock, (struct sockaddr *)&address, addrlen);
1659 	if (err)
1660 		goto out_put;
1661 
1662 	err = sock->ops->connect(sock, (struct sockaddr *)&address, addrlen,
1663 				 sock->file->f_flags);
1664 out_put:
1665 	fput_light(sock->file, fput_needed);
1666 out:
1667 	return err;
1668 }
1669 
1670 SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
1671 		int, addrlen)
1672 {
1673 	return __sys_connect(fd, uservaddr, addrlen);
1674 }
1675 
1676 /*
1677  *	Get the local address ('name') of a socket object. Move the obtained
1678  *	name to user space.
1679  */
1680 
1681 int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
1682 		      int __user *usockaddr_len)
1683 {
1684 	struct socket *sock;
1685 	struct sockaddr_storage address;
1686 	int err, fput_needed;
1687 
1688 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1689 	if (!sock)
1690 		goto out;
1691 
1692 	err = security_socket_getsockname(sock);
1693 	if (err)
1694 		goto out_put;
1695 
1696 	err = sock->ops->getname(sock, (struct sockaddr *)&address, 0);
1697 	if (err < 0)
1698 		goto out_put;
1699         /* "err" is actually length in this case */
1700 	err = move_addr_to_user(&address, err, usockaddr, usockaddr_len);
1701 
1702 out_put:
1703 	fput_light(sock->file, fput_needed);
1704 out:
1705 	return err;
1706 }
1707 
1708 SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
1709 		int __user *, usockaddr_len)
1710 {
1711 	return __sys_getsockname(fd, usockaddr, usockaddr_len);
1712 }
1713 
1714 /*
1715  *	Get the remote address ('name') of a socket object. Move the obtained
1716  *	name to user space.
1717  */
1718 
1719 int __sys_getpeername(int fd, struct sockaddr __user *usockaddr,
1720 		      int __user *usockaddr_len)
1721 {
1722 	struct socket *sock;
1723 	struct sockaddr_storage address;
1724 	int err, fput_needed;
1725 
1726 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1727 	if (sock != NULL) {
1728 		err = security_socket_getpeername(sock);
1729 		if (err) {
1730 			fput_light(sock->file, fput_needed);
1731 			return err;
1732 		}
1733 
1734 		err = sock->ops->getname(sock, (struct sockaddr *)&address, 1);
1735 		if (err >= 0)
1736 			/* "err" is actually length in this case */
1737 			err = move_addr_to_user(&address, err, usockaddr,
1738 						usockaddr_len);
1739 		fput_light(sock->file, fput_needed);
1740 	}
1741 	return err;
1742 }
1743 
1744 SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
1745 		int __user *, usockaddr_len)
1746 {
1747 	return __sys_getpeername(fd, usockaddr, usockaddr_len);
1748 }
1749 
1750 /*
1751  *	Send a datagram to a given address. We move the address into kernel
1752  *	space and check the user space data area is readable before invoking
1753  *	the protocol.
1754  */
1755 int __sys_sendto(int fd, void __user *buff, size_t len, unsigned int flags,
1756 		 struct sockaddr __user *addr,  int addr_len)
1757 {
1758 	struct socket *sock;
1759 	struct sockaddr_storage address;
1760 	int err;
1761 	struct msghdr msg;
1762 	struct iovec iov;
1763 	int fput_needed;
1764 
1765 	err = import_single_range(WRITE, buff, len, &iov, &msg.msg_iter);
1766 	if (unlikely(err))
1767 		return err;
1768 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1769 	if (!sock)
1770 		goto out;
1771 
1772 	msg.msg_name = NULL;
1773 	msg.msg_control = NULL;
1774 	msg.msg_controllen = 0;
1775 	msg.msg_namelen = 0;
1776 	if (addr) {
1777 		err = move_addr_to_kernel(addr, addr_len, &address);
1778 		if (err < 0)
1779 			goto out_put;
1780 		msg.msg_name = (struct sockaddr *)&address;
1781 		msg.msg_namelen = addr_len;
1782 	}
1783 	if (sock->file->f_flags & O_NONBLOCK)
1784 		flags |= MSG_DONTWAIT;
1785 	msg.msg_flags = flags;
1786 	err = sock_sendmsg(sock, &msg);
1787 
1788 out_put:
1789 	fput_light(sock->file, fput_needed);
1790 out:
1791 	return err;
1792 }
1793 
1794 SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
1795 		unsigned int, flags, struct sockaddr __user *, addr,
1796 		int, addr_len)
1797 {
1798 	return __sys_sendto(fd, buff, len, flags, addr, addr_len);
1799 }
1800 
1801 /*
1802  *	Send a datagram down a socket.
1803  */
1804 
1805 SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
1806 		unsigned int, flags)
1807 {
1808 	return __sys_sendto(fd, buff, len, flags, NULL, 0);
1809 }
1810 
1811 /*
1812  *	Receive a frame from the socket and optionally record the address of the
1813  *	sender. We verify the buffers are writable and if needed move the
1814  *	sender address from kernel to user space.
1815  */
1816 int __sys_recvfrom(int fd, void __user *ubuf, size_t size, unsigned int flags,
1817 		   struct sockaddr __user *addr, int __user *addr_len)
1818 {
1819 	struct socket *sock;
1820 	struct iovec iov;
1821 	struct msghdr msg;
1822 	struct sockaddr_storage address;
1823 	int err, err2;
1824 	int fput_needed;
1825 
1826 	err = import_single_range(READ, ubuf, size, &iov, &msg.msg_iter);
1827 	if (unlikely(err))
1828 		return err;
1829 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1830 	if (!sock)
1831 		goto out;
1832 
1833 	msg.msg_control = NULL;
1834 	msg.msg_controllen = 0;
1835 	/* Save some cycles and don't copy the address if not needed */
1836 	msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
1837 	/* We assume all kernel code knows the size of sockaddr_storage */
1838 	msg.msg_namelen = 0;
1839 	msg.msg_iocb = NULL;
1840 	msg.msg_flags = 0;
1841 	if (sock->file->f_flags & O_NONBLOCK)
1842 		flags |= MSG_DONTWAIT;
1843 	err = sock_recvmsg(sock, &msg, flags);
1844 
1845 	if (err >= 0 && addr != NULL) {
1846 		err2 = move_addr_to_user(&address,
1847 					 msg.msg_namelen, addr, addr_len);
1848 		if (err2 < 0)
1849 			err = err2;
1850 	}
1851 
1852 	fput_light(sock->file, fput_needed);
1853 out:
1854 	return err;
1855 }
1856 
1857 SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
1858 		unsigned int, flags, struct sockaddr __user *, addr,
1859 		int __user *, addr_len)
1860 {
1861 	return __sys_recvfrom(fd, ubuf, size, flags, addr, addr_len);
1862 }
1863 
1864 /*
1865  *	Receive a datagram from a socket.
1866  */
1867 
1868 SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
1869 		unsigned int, flags)
1870 {
1871 	return __sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
1872 }
1873 
1874 /*
1875  *	Set a socket option. Because we don't know the option lengths we have
1876  *	to pass the user mode parameter for the protocols to sort out.
1877  */
1878 
1879 static int __sys_setsockopt(int fd, int level, int optname,
1880 			    char __user *optval, int optlen)
1881 {
1882 	int err, fput_needed;
1883 	struct socket *sock;
1884 
1885 	if (optlen < 0)
1886 		return -EINVAL;
1887 
1888 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1889 	if (sock != NULL) {
1890 		err = security_socket_setsockopt(sock, level, optname);
1891 		if (err)
1892 			goto out_put;
1893 
1894 		if (level == SOL_SOCKET)
1895 			err =
1896 			    sock_setsockopt(sock, level, optname, optval,
1897 					    optlen);
1898 		else
1899 			err =
1900 			    sock->ops->setsockopt(sock, level, optname, optval,
1901 						  optlen);
1902 out_put:
1903 		fput_light(sock->file, fput_needed);
1904 	}
1905 	return err;
1906 }
1907 
1908 SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
1909 		char __user *, optval, int, optlen)
1910 {
1911 	return __sys_setsockopt(fd, level, optname, optval, optlen);
1912 }
1913 
1914 /*
1915  *	Get a socket option. Because we don't know the option lengths we have
1916  *	to pass a user mode parameter for the protocols to sort out.
1917  */
1918 
1919 static int __sys_getsockopt(int fd, int level, int optname,
1920 			    char __user *optval, int __user *optlen)
1921 {
1922 	int err, fput_needed;
1923 	struct socket *sock;
1924 
1925 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1926 	if (sock != NULL) {
1927 		err = security_socket_getsockopt(sock, level, optname);
1928 		if (err)
1929 			goto out_put;
1930 
1931 		if (level == SOL_SOCKET)
1932 			err =
1933 			    sock_getsockopt(sock, level, optname, optval,
1934 					    optlen);
1935 		else
1936 			err =
1937 			    sock->ops->getsockopt(sock, level, optname, optval,
1938 						  optlen);
1939 out_put:
1940 		fput_light(sock->file, fput_needed);
1941 	}
1942 	return err;
1943 }
1944 
1945 SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
1946 		char __user *, optval, int __user *, optlen)
1947 {
1948 	return __sys_getsockopt(fd, level, optname, optval, optlen);
1949 }
1950 
1951 /*
1952  *	Shutdown a socket.
1953  */
1954 
1955 int __sys_shutdown(int fd, int how)
1956 {
1957 	int err, fput_needed;
1958 	struct socket *sock;
1959 
1960 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1961 	if (sock != NULL) {
1962 		err = security_socket_shutdown(sock, how);
1963 		if (!err)
1964 			err = sock->ops->shutdown(sock, how);
1965 		fput_light(sock->file, fput_needed);
1966 	}
1967 	return err;
1968 }
1969 
1970 SYSCALL_DEFINE2(shutdown, int, fd, int, how)
1971 {
1972 	return __sys_shutdown(fd, how);
1973 }
1974 
1975 /* A couple of helpful macros for getting the address of the 32/64 bit
1976  * fields which are the same type (int / unsigned) on our platforms.
1977  */
1978 #define COMPAT_MSG(msg, member)	((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
1979 #define COMPAT_NAMELEN(msg)	COMPAT_MSG(msg, msg_namelen)
1980 #define COMPAT_FLAGS(msg)	COMPAT_MSG(msg, msg_flags)
1981 
1982 struct used_address {
1983 	struct sockaddr_storage name;
1984 	unsigned int name_len;
1985 };
1986 
1987 static int copy_msghdr_from_user(struct msghdr *kmsg,
1988 				 struct user_msghdr __user *umsg,
1989 				 struct sockaddr __user **save_addr,
1990 				 struct iovec **iov)
1991 {
1992 	struct user_msghdr msg;
1993 	ssize_t err;
1994 
1995 	if (copy_from_user(&msg, umsg, sizeof(*umsg)))
1996 		return -EFAULT;
1997 
1998 	kmsg->msg_control = (void __force *)msg.msg_control;
1999 	kmsg->msg_controllen = msg.msg_controllen;
2000 	kmsg->msg_flags = msg.msg_flags;
2001 
2002 	kmsg->msg_namelen = msg.msg_namelen;
2003 	if (!msg.msg_name)
2004 		kmsg->msg_namelen = 0;
2005 
2006 	if (kmsg->msg_namelen < 0)
2007 		return -EINVAL;
2008 
2009 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
2010 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
2011 
2012 	if (save_addr)
2013 		*save_addr = msg.msg_name;
2014 
2015 	if (msg.msg_name && kmsg->msg_namelen) {
2016 		if (!save_addr) {
2017 			err = move_addr_to_kernel(msg.msg_name,
2018 						  kmsg->msg_namelen,
2019 						  kmsg->msg_name);
2020 			if (err < 0)
2021 				return err;
2022 		}
2023 	} else {
2024 		kmsg->msg_name = NULL;
2025 		kmsg->msg_namelen = 0;
2026 	}
2027 
2028 	if (msg.msg_iovlen > UIO_MAXIOV)
2029 		return -EMSGSIZE;
2030 
2031 	kmsg->msg_iocb = NULL;
2032 
2033 	return import_iovec(save_addr ? READ : WRITE,
2034 			    msg.msg_iov, msg.msg_iovlen,
2035 			    UIO_FASTIOV, iov, &kmsg->msg_iter);
2036 }
2037 
2038 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
2039 			 struct msghdr *msg_sys, unsigned int flags,
2040 			 struct used_address *used_address,
2041 			 unsigned int allowed_msghdr_flags)
2042 {
2043 	struct compat_msghdr __user *msg_compat =
2044 	    (struct compat_msghdr __user *)msg;
2045 	struct sockaddr_storage address;
2046 	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
2047 	unsigned char ctl[sizeof(struct cmsghdr) + 20]
2048 				__aligned(sizeof(__kernel_size_t));
2049 	/* 20 is size of ipv6_pktinfo */
2050 	unsigned char *ctl_buf = ctl;
2051 	int ctl_len;
2052 	ssize_t err;
2053 
2054 	msg_sys->msg_name = &address;
2055 
2056 	if (MSG_CMSG_COMPAT & flags)
2057 		err = get_compat_msghdr(msg_sys, msg_compat, NULL, &iov);
2058 	else
2059 		err = copy_msghdr_from_user(msg_sys, msg, NULL, &iov);
2060 	if (err < 0)
2061 		return err;
2062 
2063 	err = -ENOBUFS;
2064 
2065 	if (msg_sys->msg_controllen > INT_MAX)
2066 		goto out_freeiov;
2067 	flags |= (msg_sys->msg_flags & allowed_msghdr_flags);
2068 	ctl_len = msg_sys->msg_controllen;
2069 	if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
2070 		err =
2071 		    cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl,
2072 						     sizeof(ctl));
2073 		if (err)
2074 			goto out_freeiov;
2075 		ctl_buf = msg_sys->msg_control;
2076 		ctl_len = msg_sys->msg_controllen;
2077 	} else if (ctl_len) {
2078 		BUILD_BUG_ON(sizeof(struct cmsghdr) !=
2079 			     CMSG_ALIGN(sizeof(struct cmsghdr)));
2080 		if (ctl_len > sizeof(ctl)) {
2081 			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
2082 			if (ctl_buf == NULL)
2083 				goto out_freeiov;
2084 		}
2085 		err = -EFAULT;
2086 		/*
2087 		 * Careful! Before this, msg_sys->msg_control contains a user pointer.
2088 		 * Afterwards, it will be a kernel pointer. Thus the compiler-assisted
2089 		 * checking falls down on this.
2090 		 */
2091 		if (copy_from_user(ctl_buf,
2092 				   (void __user __force *)msg_sys->msg_control,
2093 				   ctl_len))
2094 			goto out_freectl;
2095 		msg_sys->msg_control = ctl_buf;
2096 	}
2097 	msg_sys->msg_flags = flags;
2098 
2099 	if (sock->file->f_flags & O_NONBLOCK)
2100 		msg_sys->msg_flags |= MSG_DONTWAIT;
2101 	/*
2102 	 * If this is sendmmsg() and current destination address is same as
2103 	 * previously succeeded address, omit asking LSM's decision.
2104 	 * used_address->name_len is initialized to UINT_MAX so that the first
2105 	 * destination address never matches.
2106 	 */
2107 	if (used_address && msg_sys->msg_name &&
2108 	    used_address->name_len == msg_sys->msg_namelen &&
2109 	    !memcmp(&used_address->name, msg_sys->msg_name,
2110 		    used_address->name_len)) {
2111 		err = sock_sendmsg_nosec(sock, msg_sys);
2112 		goto out_freectl;
2113 	}
2114 	err = sock_sendmsg(sock, msg_sys);
2115 	/*
2116 	 * If this is sendmmsg() and sending to current destination address was
2117 	 * successful, remember it.
2118 	 */
2119 	if (used_address && err >= 0) {
2120 		used_address->name_len = msg_sys->msg_namelen;
2121 		if (msg_sys->msg_name)
2122 			memcpy(&used_address->name, msg_sys->msg_name,
2123 			       used_address->name_len);
2124 	}
2125 
2126 out_freectl:
2127 	if (ctl_buf != ctl)
2128 		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
2129 out_freeiov:
2130 	kfree(iov);
2131 	return err;
2132 }
2133 
2134 /*
2135  *	BSD sendmsg interface
2136  */
2137 
2138 long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2139 		   bool forbid_cmsg_compat)
2140 {
2141 	int fput_needed, err;
2142 	struct msghdr msg_sys;
2143 	struct socket *sock;
2144 
2145 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2146 		return -EINVAL;
2147 
2148 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2149 	if (!sock)
2150 		goto out;
2151 
2152 	err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL, 0);
2153 
2154 	fput_light(sock->file, fput_needed);
2155 out:
2156 	return err;
2157 }
2158 
2159 SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
2160 {
2161 	return __sys_sendmsg(fd, msg, flags, true);
2162 }
2163 
2164 /*
2165  *	Linux sendmmsg interface
2166  */
2167 
2168 int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2169 		   unsigned int flags, bool forbid_cmsg_compat)
2170 {
2171 	int fput_needed, err, datagrams;
2172 	struct socket *sock;
2173 	struct mmsghdr __user *entry;
2174 	struct compat_mmsghdr __user *compat_entry;
2175 	struct msghdr msg_sys;
2176 	struct used_address used_address;
2177 	unsigned int oflags = flags;
2178 
2179 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2180 		return -EINVAL;
2181 
2182 	if (vlen > UIO_MAXIOV)
2183 		vlen = UIO_MAXIOV;
2184 
2185 	datagrams = 0;
2186 
2187 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2188 	if (!sock)
2189 		return err;
2190 
2191 	used_address.name_len = UINT_MAX;
2192 	entry = mmsg;
2193 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2194 	err = 0;
2195 	flags |= MSG_BATCH;
2196 
2197 	while (datagrams < vlen) {
2198 		if (datagrams == vlen - 1)
2199 			flags = oflags;
2200 
2201 		if (MSG_CMSG_COMPAT & flags) {
2202 			err = ___sys_sendmsg(sock, (struct user_msghdr __user *)compat_entry,
2203 					     &msg_sys, flags, &used_address, MSG_EOR);
2204 			if (err < 0)
2205 				break;
2206 			err = __put_user(err, &compat_entry->msg_len);
2207 			++compat_entry;
2208 		} else {
2209 			err = ___sys_sendmsg(sock,
2210 					     (struct user_msghdr __user *)entry,
2211 					     &msg_sys, flags, &used_address, MSG_EOR);
2212 			if (err < 0)
2213 				break;
2214 			err = put_user(err, &entry->msg_len);
2215 			++entry;
2216 		}
2217 
2218 		if (err)
2219 			break;
2220 		++datagrams;
2221 		if (msg_data_left(&msg_sys))
2222 			break;
2223 		cond_resched();
2224 	}
2225 
2226 	fput_light(sock->file, fput_needed);
2227 
2228 	/* We only return an error if no datagrams were able to be sent */
2229 	if (datagrams != 0)
2230 		return datagrams;
2231 
2232 	return err;
2233 }
2234 
2235 SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
2236 		unsigned int, vlen, unsigned int, flags)
2237 {
2238 	return __sys_sendmmsg(fd, mmsg, vlen, flags, true);
2239 }
2240 
2241 static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
2242 			 struct msghdr *msg_sys, unsigned int flags, int nosec)
2243 {
2244 	struct compat_msghdr __user *msg_compat =
2245 	    (struct compat_msghdr __user *)msg;
2246 	struct iovec iovstack[UIO_FASTIOV];
2247 	struct iovec *iov = iovstack;
2248 	unsigned long cmsg_ptr;
2249 	int len;
2250 	ssize_t err;
2251 
2252 	/* kernel mode address */
2253 	struct sockaddr_storage addr;
2254 
2255 	/* user mode address pointers */
2256 	struct sockaddr __user *uaddr;
2257 	int __user *uaddr_len = COMPAT_NAMELEN(msg);
2258 
2259 	msg_sys->msg_name = &addr;
2260 
2261 	if (MSG_CMSG_COMPAT & flags)
2262 		err = get_compat_msghdr(msg_sys, msg_compat, &uaddr, &iov);
2263 	else
2264 		err = copy_msghdr_from_user(msg_sys, msg, &uaddr, &iov);
2265 	if (err < 0)
2266 		return err;
2267 
2268 	cmsg_ptr = (unsigned long)msg_sys->msg_control;
2269 	msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
2270 
2271 	/* We assume all kernel code knows the size of sockaddr_storage */
2272 	msg_sys->msg_namelen = 0;
2273 
2274 	if (sock->file->f_flags & O_NONBLOCK)
2275 		flags |= MSG_DONTWAIT;
2276 	err = (nosec ? sock_recvmsg_nosec : sock_recvmsg)(sock, msg_sys, flags);
2277 	if (err < 0)
2278 		goto out_freeiov;
2279 	len = err;
2280 
2281 	if (uaddr != NULL) {
2282 		err = move_addr_to_user(&addr,
2283 					msg_sys->msg_namelen, uaddr,
2284 					uaddr_len);
2285 		if (err < 0)
2286 			goto out_freeiov;
2287 	}
2288 	err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
2289 			 COMPAT_FLAGS(msg));
2290 	if (err)
2291 		goto out_freeiov;
2292 	if (MSG_CMSG_COMPAT & flags)
2293 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2294 				 &msg_compat->msg_controllen);
2295 	else
2296 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2297 				 &msg->msg_controllen);
2298 	if (err)
2299 		goto out_freeiov;
2300 	err = len;
2301 
2302 out_freeiov:
2303 	kfree(iov);
2304 	return err;
2305 }
2306 
2307 /*
2308  *	BSD recvmsg interface
2309  */
2310 
2311 long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2312 		   bool forbid_cmsg_compat)
2313 {
2314 	int fput_needed, err;
2315 	struct msghdr msg_sys;
2316 	struct socket *sock;
2317 
2318 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2319 		return -EINVAL;
2320 
2321 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2322 	if (!sock)
2323 		goto out;
2324 
2325 	err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
2326 
2327 	fput_light(sock->file, fput_needed);
2328 out:
2329 	return err;
2330 }
2331 
2332 SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
2333 		unsigned int, flags)
2334 {
2335 	return __sys_recvmsg(fd, msg, flags, true);
2336 }
2337 
2338 /*
2339  *     Linux recvmmsg interface
2340  */
2341 
2342 int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2343 		   unsigned int flags, struct timespec64 *timeout)
2344 {
2345 	int fput_needed, err, datagrams;
2346 	struct socket *sock;
2347 	struct mmsghdr __user *entry;
2348 	struct compat_mmsghdr __user *compat_entry;
2349 	struct msghdr msg_sys;
2350 	struct timespec64 end_time;
2351 	struct timespec64 timeout64;
2352 
2353 	if (timeout &&
2354 	    poll_select_set_timeout(&end_time, timeout->tv_sec,
2355 				    timeout->tv_nsec))
2356 		return -EINVAL;
2357 
2358 	datagrams = 0;
2359 
2360 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2361 	if (!sock)
2362 		return err;
2363 
2364 	if (likely(!(flags & MSG_ERRQUEUE))) {
2365 		err = sock_error(sock->sk);
2366 		if (err) {
2367 			datagrams = err;
2368 			goto out_put;
2369 		}
2370 	}
2371 
2372 	entry = mmsg;
2373 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2374 
2375 	while (datagrams < vlen) {
2376 		/*
2377 		 * No need to ask LSM for more than the first datagram.
2378 		 */
2379 		if (MSG_CMSG_COMPAT & flags) {
2380 			err = ___sys_recvmsg(sock, (struct user_msghdr __user *)compat_entry,
2381 					     &msg_sys, flags & ~MSG_WAITFORONE,
2382 					     datagrams);
2383 			if (err < 0)
2384 				break;
2385 			err = __put_user(err, &compat_entry->msg_len);
2386 			++compat_entry;
2387 		} else {
2388 			err = ___sys_recvmsg(sock,
2389 					     (struct user_msghdr __user *)entry,
2390 					     &msg_sys, flags & ~MSG_WAITFORONE,
2391 					     datagrams);
2392 			if (err < 0)
2393 				break;
2394 			err = put_user(err, &entry->msg_len);
2395 			++entry;
2396 		}
2397 
2398 		if (err)
2399 			break;
2400 		++datagrams;
2401 
2402 		/* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */
2403 		if (flags & MSG_WAITFORONE)
2404 			flags |= MSG_DONTWAIT;
2405 
2406 		if (timeout) {
2407 			ktime_get_ts64(&timeout64);
2408 			*timeout = timespec64_sub(end_time, timeout64);
2409 			if (timeout->tv_sec < 0) {
2410 				timeout->tv_sec = timeout->tv_nsec = 0;
2411 				break;
2412 			}
2413 
2414 			/* Timeout, return less than vlen datagrams */
2415 			if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
2416 				break;
2417 		}
2418 
2419 		/* Out of band data, return right away */
2420 		if (msg_sys.msg_flags & MSG_OOB)
2421 			break;
2422 		cond_resched();
2423 	}
2424 
2425 	if (err == 0)
2426 		goto out_put;
2427 
2428 	if (datagrams == 0) {
2429 		datagrams = err;
2430 		goto out_put;
2431 	}
2432 
2433 	/*
2434 	 * We may return less entries than requested (vlen) if the
2435 	 * sock is non block and there aren't enough datagrams...
2436 	 */
2437 	if (err != -EAGAIN) {
2438 		/*
2439 		 * ... or  if recvmsg returns an error after we
2440 		 * received some datagrams, where we record the
2441 		 * error to return on the next call or if the
2442 		 * app asks about it using getsockopt(SO_ERROR).
2443 		 */
2444 		sock->sk->sk_err = -err;
2445 	}
2446 out_put:
2447 	fput_light(sock->file, fput_needed);
2448 
2449 	return datagrams;
2450 }
2451 
2452 static int do_sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
2453 			   unsigned int vlen, unsigned int flags,
2454 			   struct __kernel_timespec __user *timeout)
2455 {
2456 	int datagrams;
2457 	struct timespec64 timeout_sys;
2458 
2459 	if (flags & MSG_CMSG_COMPAT)
2460 		return -EINVAL;
2461 
2462 	if (!timeout)
2463 		return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL);
2464 
2465 	if (get_timespec64(&timeout_sys, timeout))
2466 		return -EFAULT;
2467 
2468 	datagrams = __sys_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
2469 
2470 	if (datagrams > 0 && put_timespec64(&timeout_sys, timeout))
2471 		datagrams = -EFAULT;
2472 
2473 	return datagrams;
2474 }
2475 
2476 SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
2477 		unsigned int, vlen, unsigned int, flags,
2478 		struct __kernel_timespec __user *, timeout)
2479 {
2480 	return do_sys_recvmmsg(fd, mmsg, vlen, flags, timeout);
2481 }
2482 
2483 #ifdef __ARCH_WANT_SYS_SOCKETCALL
2484 /* Argument list sizes for sys_socketcall */
2485 #define AL(x) ((x) * sizeof(unsigned long))
2486 static const unsigned char nargs[21] = {
2487 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
2488 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
2489 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
2490 	AL(4), AL(5), AL(4)
2491 };
2492 
2493 #undef AL
2494 
2495 /*
2496  *	System call vectors.
2497  *
2498  *	Argument checking cleaned up. Saved 20% in size.
2499  *  This function doesn't need to set the kernel lock because
2500  *  it is set by the callees.
2501  */
2502 
2503 SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
2504 {
2505 	unsigned long a[AUDITSC_ARGS];
2506 	unsigned long a0, a1;
2507 	int err;
2508 	unsigned int len;
2509 
2510 	if (call < 1 || call > SYS_SENDMMSG)
2511 		return -EINVAL;
2512 	call = array_index_nospec(call, SYS_SENDMMSG + 1);
2513 
2514 	len = nargs[call];
2515 	if (len > sizeof(a))
2516 		return -EINVAL;
2517 
2518 	/* copy_from_user should be SMP safe. */
2519 	if (copy_from_user(a, args, len))
2520 		return -EFAULT;
2521 
2522 	err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
2523 	if (err)
2524 		return err;
2525 
2526 	a0 = a[0];
2527 	a1 = a[1];
2528 
2529 	switch (call) {
2530 	case SYS_SOCKET:
2531 		err = __sys_socket(a0, a1, a[2]);
2532 		break;
2533 	case SYS_BIND:
2534 		err = __sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
2535 		break;
2536 	case SYS_CONNECT:
2537 		err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
2538 		break;
2539 	case SYS_LISTEN:
2540 		err = __sys_listen(a0, a1);
2541 		break;
2542 	case SYS_ACCEPT:
2543 		err = __sys_accept4(a0, (struct sockaddr __user *)a1,
2544 				    (int __user *)a[2], 0);
2545 		break;
2546 	case SYS_GETSOCKNAME:
2547 		err =
2548 		    __sys_getsockname(a0, (struct sockaddr __user *)a1,
2549 				      (int __user *)a[2]);
2550 		break;
2551 	case SYS_GETPEERNAME:
2552 		err =
2553 		    __sys_getpeername(a0, (struct sockaddr __user *)a1,
2554 				      (int __user *)a[2]);
2555 		break;
2556 	case SYS_SOCKETPAIR:
2557 		err = __sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
2558 		break;
2559 	case SYS_SEND:
2560 		err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
2561 				   NULL, 0);
2562 		break;
2563 	case SYS_SENDTO:
2564 		err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
2565 				   (struct sockaddr __user *)a[4], a[5]);
2566 		break;
2567 	case SYS_RECV:
2568 		err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2569 				     NULL, NULL);
2570 		break;
2571 	case SYS_RECVFROM:
2572 		err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2573 				     (struct sockaddr __user *)a[4],
2574 				     (int __user *)a[5]);
2575 		break;
2576 	case SYS_SHUTDOWN:
2577 		err = __sys_shutdown(a0, a1);
2578 		break;
2579 	case SYS_SETSOCKOPT:
2580 		err = __sys_setsockopt(a0, a1, a[2], (char __user *)a[3],
2581 				       a[4]);
2582 		break;
2583 	case SYS_GETSOCKOPT:
2584 		err =
2585 		    __sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
2586 				     (int __user *)a[4]);
2587 		break;
2588 	case SYS_SENDMSG:
2589 		err = __sys_sendmsg(a0, (struct user_msghdr __user *)a1,
2590 				    a[2], true);
2591 		break;
2592 	case SYS_SENDMMSG:
2593 		err = __sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2],
2594 				     a[3], true);
2595 		break;
2596 	case SYS_RECVMSG:
2597 		err = __sys_recvmsg(a0, (struct user_msghdr __user *)a1,
2598 				    a[2], true);
2599 		break;
2600 	case SYS_RECVMMSG:
2601 		err = do_sys_recvmmsg(a0, (struct mmsghdr __user *)a1, a[2],
2602 				      a[3], (struct __kernel_timespec __user *)a[4]);
2603 		break;
2604 	case SYS_ACCEPT4:
2605 		err = __sys_accept4(a0, (struct sockaddr __user *)a1,
2606 				    (int __user *)a[2], a[3]);
2607 		break;
2608 	default:
2609 		err = -EINVAL;
2610 		break;
2611 	}
2612 	return err;
2613 }
2614 
2615 #endif				/* __ARCH_WANT_SYS_SOCKETCALL */
2616 
2617 /**
2618  *	sock_register - add a socket protocol handler
2619  *	@ops: description of protocol
2620  *
2621  *	This function is called by a protocol handler that wants to
2622  *	advertise its address family, and have it linked into the
2623  *	socket interface. The value ops->family corresponds to the
2624  *	socket system call protocol family.
2625  */
2626 int sock_register(const struct net_proto_family *ops)
2627 {
2628 	int err;
2629 
2630 	if (ops->family >= NPROTO) {
2631 		pr_crit("protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
2632 		return -ENOBUFS;
2633 	}
2634 
2635 	spin_lock(&net_family_lock);
2636 	if (rcu_dereference_protected(net_families[ops->family],
2637 				      lockdep_is_held(&net_family_lock)))
2638 		err = -EEXIST;
2639 	else {
2640 		rcu_assign_pointer(net_families[ops->family], ops);
2641 		err = 0;
2642 	}
2643 	spin_unlock(&net_family_lock);
2644 
2645 	pr_info("NET: Registered protocol family %d\n", ops->family);
2646 	return err;
2647 }
2648 EXPORT_SYMBOL(sock_register);
2649 
2650 /**
2651  *	sock_unregister - remove a protocol handler
2652  *	@family: protocol family to remove
2653  *
2654  *	This function is called by a protocol handler that wants to
2655  *	remove its address family, and have it unlinked from the
2656  *	new socket creation.
2657  *
2658  *	If protocol handler is a module, then it can use module reference
2659  *	counts to protect against new references. If protocol handler is not
2660  *	a module then it needs to provide its own protection in
2661  *	the ops->create routine.
2662  */
2663 void sock_unregister(int family)
2664 {
2665 	BUG_ON(family < 0 || family >= NPROTO);
2666 
2667 	spin_lock(&net_family_lock);
2668 	RCU_INIT_POINTER(net_families[family], NULL);
2669 	spin_unlock(&net_family_lock);
2670 
2671 	synchronize_rcu();
2672 
2673 	pr_info("NET: Unregistered protocol family %d\n", family);
2674 }
2675 EXPORT_SYMBOL(sock_unregister);
2676 
2677 bool sock_is_registered(int family)
2678 {
2679 	return family < NPROTO && rcu_access_pointer(net_families[family]);
2680 }
2681 
2682 static int __init sock_init(void)
2683 {
2684 	int err;
2685 	/*
2686 	 *      Initialize the network sysctl infrastructure.
2687 	 */
2688 	err = net_sysctl_init();
2689 	if (err)
2690 		goto out;
2691 
2692 	/*
2693 	 *      Initialize skbuff SLAB cache
2694 	 */
2695 	skb_init();
2696 
2697 	/*
2698 	 *      Initialize the protocols module.
2699 	 */
2700 
2701 	init_inodecache();
2702 
2703 	err = register_filesystem(&sock_fs_type);
2704 	if (err)
2705 		goto out_fs;
2706 	sock_mnt = kern_mount(&sock_fs_type);
2707 	if (IS_ERR(sock_mnt)) {
2708 		err = PTR_ERR(sock_mnt);
2709 		goto out_mount;
2710 	}
2711 
2712 	/* The real protocol initialization is performed in later initcalls.
2713 	 */
2714 
2715 #ifdef CONFIG_NETFILTER
2716 	err = netfilter_init();
2717 	if (err)
2718 		goto out;
2719 #endif
2720 
2721 	ptp_classifier_init();
2722 
2723 out:
2724 	return err;
2725 
2726 out_mount:
2727 	unregister_filesystem(&sock_fs_type);
2728 out_fs:
2729 	goto out;
2730 }
2731 
2732 core_initcall(sock_init);	/* early initcall */
2733 
2734 #ifdef CONFIG_PROC_FS
2735 void socket_seq_show(struct seq_file *seq)
2736 {
2737 	seq_printf(seq, "sockets: used %d\n",
2738 		   sock_inuse_get(seq->private));
2739 }
2740 #endif				/* CONFIG_PROC_FS */
2741 
2742 #ifdef CONFIG_COMPAT
2743 static int do_siocgstamp(struct net *net, struct socket *sock,
2744 			 unsigned int cmd, void __user *up)
2745 {
2746 	mm_segment_t old_fs = get_fs();
2747 	struct timeval ktv;
2748 	int err;
2749 
2750 	set_fs(KERNEL_DS);
2751 	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&ktv);
2752 	set_fs(old_fs);
2753 	if (!err)
2754 		err = compat_put_timeval(&ktv, up);
2755 
2756 	return err;
2757 }
2758 
2759 static int do_siocgstampns(struct net *net, struct socket *sock,
2760 			   unsigned int cmd, void __user *up)
2761 {
2762 	mm_segment_t old_fs = get_fs();
2763 	struct timespec kts;
2764 	int err;
2765 
2766 	set_fs(KERNEL_DS);
2767 	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&kts);
2768 	set_fs(old_fs);
2769 	if (!err)
2770 		err = compat_put_timespec(&kts, up);
2771 
2772 	return err;
2773 }
2774 
2775 static int compat_dev_ifconf(struct net *net, struct compat_ifconf __user *uifc32)
2776 {
2777 	struct compat_ifconf ifc32;
2778 	struct ifconf ifc;
2779 	int err;
2780 
2781 	if (copy_from_user(&ifc32, uifc32, sizeof(struct compat_ifconf)))
2782 		return -EFAULT;
2783 
2784 	ifc.ifc_len = ifc32.ifc_len;
2785 	ifc.ifc_req = compat_ptr(ifc32.ifcbuf);
2786 
2787 	rtnl_lock();
2788 	err = dev_ifconf(net, &ifc, sizeof(struct compat_ifreq));
2789 	rtnl_unlock();
2790 	if (err)
2791 		return err;
2792 
2793 	ifc32.ifc_len = ifc.ifc_len;
2794 	if (copy_to_user(uifc32, &ifc32, sizeof(struct compat_ifconf)))
2795 		return -EFAULT;
2796 
2797 	return 0;
2798 }
2799 
2800 static int ethtool_ioctl(struct net *net, struct compat_ifreq __user *ifr32)
2801 {
2802 	struct compat_ethtool_rxnfc __user *compat_rxnfc;
2803 	bool convert_in = false, convert_out = false;
2804 	size_t buf_size = 0;
2805 	struct ethtool_rxnfc __user *rxnfc = NULL;
2806 	struct ifreq ifr;
2807 	u32 rule_cnt = 0, actual_rule_cnt;
2808 	u32 ethcmd;
2809 	u32 data;
2810 	int ret;
2811 
2812 	if (get_user(data, &ifr32->ifr_ifru.ifru_data))
2813 		return -EFAULT;
2814 
2815 	compat_rxnfc = compat_ptr(data);
2816 
2817 	if (get_user(ethcmd, &compat_rxnfc->cmd))
2818 		return -EFAULT;
2819 
2820 	/* Most ethtool structures are defined without padding.
2821 	 * Unfortunately struct ethtool_rxnfc is an exception.
2822 	 */
2823 	switch (ethcmd) {
2824 	default:
2825 		break;
2826 	case ETHTOOL_GRXCLSRLALL:
2827 		/* Buffer size is variable */
2828 		if (get_user(rule_cnt, &compat_rxnfc->rule_cnt))
2829 			return -EFAULT;
2830 		if (rule_cnt > KMALLOC_MAX_SIZE / sizeof(u32))
2831 			return -ENOMEM;
2832 		buf_size += rule_cnt * sizeof(u32);
2833 		/* fall through */
2834 	case ETHTOOL_GRXRINGS:
2835 	case ETHTOOL_GRXCLSRLCNT:
2836 	case ETHTOOL_GRXCLSRULE:
2837 	case ETHTOOL_SRXCLSRLINS:
2838 		convert_out = true;
2839 		/* fall through */
2840 	case ETHTOOL_SRXCLSRLDEL:
2841 		buf_size += sizeof(struct ethtool_rxnfc);
2842 		convert_in = true;
2843 		rxnfc = compat_alloc_user_space(buf_size);
2844 		break;
2845 	}
2846 
2847 	if (copy_from_user(&ifr.ifr_name, &ifr32->ifr_name, IFNAMSIZ))
2848 		return -EFAULT;
2849 
2850 	ifr.ifr_data = convert_in ? rxnfc : (void __user *)compat_rxnfc;
2851 
2852 	if (convert_in) {
2853 		/* We expect there to be holes between fs.m_ext and
2854 		 * fs.ring_cookie and at the end of fs, but nowhere else.
2855 		 */
2856 		BUILD_BUG_ON(offsetof(struct compat_ethtool_rxnfc, fs.m_ext) +
2857 			     sizeof(compat_rxnfc->fs.m_ext) !=
2858 			     offsetof(struct ethtool_rxnfc, fs.m_ext) +
2859 			     sizeof(rxnfc->fs.m_ext));
2860 		BUILD_BUG_ON(
2861 			offsetof(struct compat_ethtool_rxnfc, fs.location) -
2862 			offsetof(struct compat_ethtool_rxnfc, fs.ring_cookie) !=
2863 			offsetof(struct ethtool_rxnfc, fs.location) -
2864 			offsetof(struct ethtool_rxnfc, fs.ring_cookie));
2865 
2866 		if (copy_in_user(rxnfc, compat_rxnfc,
2867 				 (void __user *)(&rxnfc->fs.m_ext + 1) -
2868 				 (void __user *)rxnfc) ||
2869 		    copy_in_user(&rxnfc->fs.ring_cookie,
2870 				 &compat_rxnfc->fs.ring_cookie,
2871 				 (void __user *)(&rxnfc->fs.location + 1) -
2872 				 (void __user *)&rxnfc->fs.ring_cookie) ||
2873 		    copy_in_user(&rxnfc->rule_cnt, &compat_rxnfc->rule_cnt,
2874 				 sizeof(rxnfc->rule_cnt)))
2875 			return -EFAULT;
2876 	}
2877 
2878 	ret = dev_ioctl(net, SIOCETHTOOL, &ifr, NULL);
2879 	if (ret)
2880 		return ret;
2881 
2882 	if (convert_out) {
2883 		if (copy_in_user(compat_rxnfc, rxnfc,
2884 				 (const void __user *)(&rxnfc->fs.m_ext + 1) -
2885 				 (const void __user *)rxnfc) ||
2886 		    copy_in_user(&compat_rxnfc->fs.ring_cookie,
2887 				 &rxnfc->fs.ring_cookie,
2888 				 (const void __user *)(&rxnfc->fs.location + 1) -
2889 				 (const void __user *)&rxnfc->fs.ring_cookie) ||
2890 		    copy_in_user(&compat_rxnfc->rule_cnt, &rxnfc->rule_cnt,
2891 				 sizeof(rxnfc->rule_cnt)))
2892 			return -EFAULT;
2893 
2894 		if (ethcmd == ETHTOOL_GRXCLSRLALL) {
2895 			/* As an optimisation, we only copy the actual
2896 			 * number of rules that the underlying
2897 			 * function returned.  Since Mallory might
2898 			 * change the rule count in user memory, we
2899 			 * check that it is less than the rule count
2900 			 * originally given (as the user buffer size),
2901 			 * which has been range-checked.
2902 			 */
2903 			if (get_user(actual_rule_cnt, &rxnfc->rule_cnt))
2904 				return -EFAULT;
2905 			if (actual_rule_cnt < rule_cnt)
2906 				rule_cnt = actual_rule_cnt;
2907 			if (copy_in_user(&compat_rxnfc->rule_locs[0],
2908 					 &rxnfc->rule_locs[0],
2909 					 rule_cnt * sizeof(u32)))
2910 				return -EFAULT;
2911 		}
2912 	}
2913 
2914 	return 0;
2915 }
2916 
2917 static int compat_siocwandev(struct net *net, struct compat_ifreq __user *uifr32)
2918 {
2919 	compat_uptr_t uptr32;
2920 	struct ifreq ifr;
2921 	void __user *saved;
2922 	int err;
2923 
2924 	if (copy_from_user(&ifr, uifr32, sizeof(struct compat_ifreq)))
2925 		return -EFAULT;
2926 
2927 	if (get_user(uptr32, &uifr32->ifr_settings.ifs_ifsu))
2928 		return -EFAULT;
2929 
2930 	saved = ifr.ifr_settings.ifs_ifsu.raw_hdlc;
2931 	ifr.ifr_settings.ifs_ifsu.raw_hdlc = compat_ptr(uptr32);
2932 
2933 	err = dev_ioctl(net, SIOCWANDEV, &ifr, NULL);
2934 	if (!err) {
2935 		ifr.ifr_settings.ifs_ifsu.raw_hdlc = saved;
2936 		if (copy_to_user(uifr32, &ifr, sizeof(struct compat_ifreq)))
2937 			err = -EFAULT;
2938 	}
2939 	return err;
2940 }
2941 
2942 /* Handle ioctls that use ifreq::ifr_data and just need struct ifreq converted */
2943 static int compat_ifr_data_ioctl(struct net *net, unsigned int cmd,
2944 				 struct compat_ifreq __user *u_ifreq32)
2945 {
2946 	struct ifreq ifreq;
2947 	u32 data32;
2948 
2949 	if (copy_from_user(ifreq.ifr_name, u_ifreq32->ifr_name, IFNAMSIZ))
2950 		return -EFAULT;
2951 	if (get_user(data32, &u_ifreq32->ifr_data))
2952 		return -EFAULT;
2953 	ifreq.ifr_data = compat_ptr(data32);
2954 
2955 	return dev_ioctl(net, cmd, &ifreq, NULL);
2956 }
2957 
2958 static int compat_sioc_ifmap(struct net *net, unsigned int cmd,
2959 			struct compat_ifreq __user *uifr32)
2960 {
2961 	struct ifreq ifr;
2962 	struct compat_ifmap __user *uifmap32;
2963 	int err;
2964 
2965 	uifmap32 = &uifr32->ifr_ifru.ifru_map;
2966 	err = copy_from_user(&ifr, uifr32, sizeof(ifr.ifr_name));
2967 	err |= get_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
2968 	err |= get_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
2969 	err |= get_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
2970 	err |= get_user(ifr.ifr_map.irq, &uifmap32->irq);
2971 	err |= get_user(ifr.ifr_map.dma, &uifmap32->dma);
2972 	err |= get_user(ifr.ifr_map.port, &uifmap32->port);
2973 	if (err)
2974 		return -EFAULT;
2975 
2976 	err = dev_ioctl(net, cmd, &ifr, NULL);
2977 
2978 	if (cmd == SIOCGIFMAP && !err) {
2979 		err = copy_to_user(uifr32, &ifr, sizeof(ifr.ifr_name));
2980 		err |= put_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
2981 		err |= put_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
2982 		err |= put_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
2983 		err |= put_user(ifr.ifr_map.irq, &uifmap32->irq);
2984 		err |= put_user(ifr.ifr_map.dma, &uifmap32->dma);
2985 		err |= put_user(ifr.ifr_map.port, &uifmap32->port);
2986 		if (err)
2987 			err = -EFAULT;
2988 	}
2989 	return err;
2990 }
2991 
2992 struct rtentry32 {
2993 	u32		rt_pad1;
2994 	struct sockaddr rt_dst;         /* target address               */
2995 	struct sockaddr rt_gateway;     /* gateway addr (RTF_GATEWAY)   */
2996 	struct sockaddr rt_genmask;     /* target network mask (IP)     */
2997 	unsigned short	rt_flags;
2998 	short		rt_pad2;
2999 	u32		rt_pad3;
3000 	unsigned char	rt_tos;
3001 	unsigned char	rt_class;
3002 	short		rt_pad4;
3003 	short		rt_metric;      /* +1 for binary compatibility! */
3004 	/* char * */ u32 rt_dev;        /* forcing the device at add    */
3005 	u32		rt_mtu;         /* per route MTU/Window         */
3006 	u32		rt_window;      /* Window clamping              */
3007 	unsigned short  rt_irtt;        /* Initial RTT                  */
3008 };
3009 
3010 struct in6_rtmsg32 {
3011 	struct in6_addr		rtmsg_dst;
3012 	struct in6_addr		rtmsg_src;
3013 	struct in6_addr		rtmsg_gateway;
3014 	u32			rtmsg_type;
3015 	u16			rtmsg_dst_len;
3016 	u16			rtmsg_src_len;
3017 	u32			rtmsg_metric;
3018 	u32			rtmsg_info;
3019 	u32			rtmsg_flags;
3020 	s32			rtmsg_ifindex;
3021 };
3022 
3023 static int routing_ioctl(struct net *net, struct socket *sock,
3024 			 unsigned int cmd, void __user *argp)
3025 {
3026 	int ret;
3027 	void *r = NULL;
3028 	struct in6_rtmsg r6;
3029 	struct rtentry r4;
3030 	char devname[16];
3031 	u32 rtdev;
3032 	mm_segment_t old_fs = get_fs();
3033 
3034 	if (sock && sock->sk && sock->sk->sk_family == AF_INET6) { /* ipv6 */
3035 		struct in6_rtmsg32 __user *ur6 = argp;
3036 		ret = copy_from_user(&r6.rtmsg_dst, &(ur6->rtmsg_dst),
3037 			3 * sizeof(struct in6_addr));
3038 		ret |= get_user(r6.rtmsg_type, &(ur6->rtmsg_type));
3039 		ret |= get_user(r6.rtmsg_dst_len, &(ur6->rtmsg_dst_len));
3040 		ret |= get_user(r6.rtmsg_src_len, &(ur6->rtmsg_src_len));
3041 		ret |= get_user(r6.rtmsg_metric, &(ur6->rtmsg_metric));
3042 		ret |= get_user(r6.rtmsg_info, &(ur6->rtmsg_info));
3043 		ret |= get_user(r6.rtmsg_flags, &(ur6->rtmsg_flags));
3044 		ret |= get_user(r6.rtmsg_ifindex, &(ur6->rtmsg_ifindex));
3045 
3046 		r = (void *) &r6;
3047 	} else { /* ipv4 */
3048 		struct rtentry32 __user *ur4 = argp;
3049 		ret = copy_from_user(&r4.rt_dst, &(ur4->rt_dst),
3050 					3 * sizeof(struct sockaddr));
3051 		ret |= get_user(r4.rt_flags, &(ur4->rt_flags));
3052 		ret |= get_user(r4.rt_metric, &(ur4->rt_metric));
3053 		ret |= get_user(r4.rt_mtu, &(ur4->rt_mtu));
3054 		ret |= get_user(r4.rt_window, &(ur4->rt_window));
3055 		ret |= get_user(r4.rt_irtt, &(ur4->rt_irtt));
3056 		ret |= get_user(rtdev, &(ur4->rt_dev));
3057 		if (rtdev) {
3058 			ret |= copy_from_user(devname, compat_ptr(rtdev), 15);
3059 			r4.rt_dev = (char __user __force *)devname;
3060 			devname[15] = 0;
3061 		} else
3062 			r4.rt_dev = NULL;
3063 
3064 		r = (void *) &r4;
3065 	}
3066 
3067 	if (ret) {
3068 		ret = -EFAULT;
3069 		goto out;
3070 	}
3071 
3072 	set_fs(KERNEL_DS);
3073 	ret = sock_do_ioctl(net, sock, cmd, (unsigned long) r);
3074 	set_fs(old_fs);
3075 
3076 out:
3077 	return ret;
3078 }
3079 
3080 /* Since old style bridge ioctl's endup using SIOCDEVPRIVATE
3081  * for some operations; this forces use of the newer bridge-utils that
3082  * use compatible ioctls
3083  */
3084 static int old_bridge_ioctl(compat_ulong_t __user *argp)
3085 {
3086 	compat_ulong_t tmp;
3087 
3088 	if (get_user(tmp, argp))
3089 		return -EFAULT;
3090 	if (tmp == BRCTL_GET_VERSION)
3091 		return BRCTL_VERSION + 1;
3092 	return -EINVAL;
3093 }
3094 
3095 static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
3096 			 unsigned int cmd, unsigned long arg)
3097 {
3098 	void __user *argp = compat_ptr(arg);
3099 	struct sock *sk = sock->sk;
3100 	struct net *net = sock_net(sk);
3101 
3102 	if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))
3103 		return compat_ifr_data_ioctl(net, cmd, argp);
3104 
3105 	switch (cmd) {
3106 	case SIOCSIFBR:
3107 	case SIOCGIFBR:
3108 		return old_bridge_ioctl(argp);
3109 	case SIOCGIFCONF:
3110 		return compat_dev_ifconf(net, argp);
3111 	case SIOCETHTOOL:
3112 		return ethtool_ioctl(net, argp);
3113 	case SIOCWANDEV:
3114 		return compat_siocwandev(net, argp);
3115 	case SIOCGIFMAP:
3116 	case SIOCSIFMAP:
3117 		return compat_sioc_ifmap(net, cmd, argp);
3118 	case SIOCADDRT:
3119 	case SIOCDELRT:
3120 		return routing_ioctl(net, sock, cmd, argp);
3121 	case SIOCGSTAMP:
3122 		return do_siocgstamp(net, sock, cmd, argp);
3123 	case SIOCGSTAMPNS:
3124 		return do_siocgstampns(net, sock, cmd, argp);
3125 	case SIOCBONDSLAVEINFOQUERY:
3126 	case SIOCBONDINFOQUERY:
3127 	case SIOCSHWTSTAMP:
3128 	case SIOCGHWTSTAMP:
3129 		return compat_ifr_data_ioctl(net, cmd, argp);
3130 
3131 	case FIOSETOWN:
3132 	case SIOCSPGRP:
3133 	case FIOGETOWN:
3134 	case SIOCGPGRP:
3135 	case SIOCBRADDBR:
3136 	case SIOCBRDELBR:
3137 	case SIOCGIFVLAN:
3138 	case SIOCSIFVLAN:
3139 	case SIOCADDDLCI:
3140 	case SIOCDELDLCI:
3141 	case SIOCGSKNS:
3142 		return sock_ioctl(file, cmd, arg);
3143 
3144 	case SIOCGIFFLAGS:
3145 	case SIOCSIFFLAGS:
3146 	case SIOCGIFMETRIC:
3147 	case SIOCSIFMETRIC:
3148 	case SIOCGIFMTU:
3149 	case SIOCSIFMTU:
3150 	case SIOCGIFMEM:
3151 	case SIOCSIFMEM:
3152 	case SIOCGIFHWADDR:
3153 	case SIOCSIFHWADDR:
3154 	case SIOCADDMULTI:
3155 	case SIOCDELMULTI:
3156 	case SIOCGIFINDEX:
3157 	case SIOCGIFADDR:
3158 	case SIOCSIFADDR:
3159 	case SIOCSIFHWBROADCAST:
3160 	case SIOCDIFADDR:
3161 	case SIOCGIFBRDADDR:
3162 	case SIOCSIFBRDADDR:
3163 	case SIOCGIFDSTADDR:
3164 	case SIOCSIFDSTADDR:
3165 	case SIOCGIFNETMASK:
3166 	case SIOCSIFNETMASK:
3167 	case SIOCSIFPFLAGS:
3168 	case SIOCGIFPFLAGS:
3169 	case SIOCGIFTXQLEN:
3170 	case SIOCSIFTXQLEN:
3171 	case SIOCBRADDIF:
3172 	case SIOCBRDELIF:
3173 	case SIOCSIFNAME:
3174 	case SIOCGMIIPHY:
3175 	case SIOCGMIIREG:
3176 	case SIOCSMIIREG:
3177 	case SIOCSARP:
3178 	case SIOCGARP:
3179 	case SIOCDARP:
3180 	case SIOCATMARK:
3181 	case SIOCBONDENSLAVE:
3182 	case SIOCBONDRELEASE:
3183 	case SIOCBONDSETHWADDR:
3184 	case SIOCBONDCHANGEACTIVE:
3185 	case SIOCGIFNAME:
3186 		return sock_do_ioctl(net, sock, cmd, arg);
3187 	}
3188 
3189 	return -ENOIOCTLCMD;
3190 }
3191 
3192 static long compat_sock_ioctl(struct file *file, unsigned int cmd,
3193 			      unsigned long arg)
3194 {
3195 	struct socket *sock = file->private_data;
3196 	int ret = -ENOIOCTLCMD;
3197 	struct sock *sk;
3198 	struct net *net;
3199 
3200 	sk = sock->sk;
3201 	net = sock_net(sk);
3202 
3203 	if (sock->ops->compat_ioctl)
3204 		ret = sock->ops->compat_ioctl(sock, cmd, arg);
3205 
3206 	if (ret == -ENOIOCTLCMD &&
3207 	    (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
3208 		ret = compat_wext_handle_ioctl(net, cmd, arg);
3209 
3210 	if (ret == -ENOIOCTLCMD)
3211 		ret = compat_sock_ioctl_trans(file, sock, cmd, arg);
3212 
3213 	return ret;
3214 }
3215 #endif
3216 
3217 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
3218 {
3219 	return sock->ops->bind(sock, addr, addrlen);
3220 }
3221 EXPORT_SYMBOL(kernel_bind);
3222 
3223 int kernel_listen(struct socket *sock, int backlog)
3224 {
3225 	return sock->ops->listen(sock, backlog);
3226 }
3227 EXPORT_SYMBOL(kernel_listen);
3228 
3229 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
3230 {
3231 	struct sock *sk = sock->sk;
3232 	int err;
3233 
3234 	err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
3235 			       newsock);
3236 	if (err < 0)
3237 		goto done;
3238 
3239 	err = sock->ops->accept(sock, *newsock, flags, true);
3240 	if (err < 0) {
3241 		sock_release(*newsock);
3242 		*newsock = NULL;
3243 		goto done;
3244 	}
3245 
3246 	(*newsock)->ops = sock->ops;
3247 	__module_get((*newsock)->ops->owner);
3248 
3249 done:
3250 	return err;
3251 }
3252 EXPORT_SYMBOL(kernel_accept);
3253 
3254 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
3255 		   int flags)
3256 {
3257 	return sock->ops->connect(sock, addr, addrlen, flags);
3258 }
3259 EXPORT_SYMBOL(kernel_connect);
3260 
3261 int kernel_getsockname(struct socket *sock, struct sockaddr *addr)
3262 {
3263 	return sock->ops->getname(sock, addr, 0);
3264 }
3265 EXPORT_SYMBOL(kernel_getsockname);
3266 
3267 int kernel_getpeername(struct socket *sock, struct sockaddr *addr)
3268 {
3269 	return sock->ops->getname(sock, addr, 1);
3270 }
3271 EXPORT_SYMBOL(kernel_getpeername);
3272 
3273 int kernel_getsockopt(struct socket *sock, int level, int optname,
3274 			char *optval, int *optlen)
3275 {
3276 	mm_segment_t oldfs = get_fs();
3277 	char __user *uoptval;
3278 	int __user *uoptlen;
3279 	int err;
3280 
3281 	uoptval = (char __user __force *) optval;
3282 	uoptlen = (int __user __force *) optlen;
3283 
3284 	set_fs(KERNEL_DS);
3285 	if (level == SOL_SOCKET)
3286 		err = sock_getsockopt(sock, level, optname, uoptval, uoptlen);
3287 	else
3288 		err = sock->ops->getsockopt(sock, level, optname, uoptval,
3289 					    uoptlen);
3290 	set_fs(oldfs);
3291 	return err;
3292 }
3293 EXPORT_SYMBOL(kernel_getsockopt);
3294 
3295 int kernel_setsockopt(struct socket *sock, int level, int optname,
3296 			char *optval, unsigned int optlen)
3297 {
3298 	mm_segment_t oldfs = get_fs();
3299 	char __user *uoptval;
3300 	int err;
3301 
3302 	uoptval = (char __user __force *) optval;
3303 
3304 	set_fs(KERNEL_DS);
3305 	if (level == SOL_SOCKET)
3306 		err = sock_setsockopt(sock, level, optname, uoptval, optlen);
3307 	else
3308 		err = sock->ops->setsockopt(sock, level, optname, uoptval,
3309 					    optlen);
3310 	set_fs(oldfs);
3311 	return err;
3312 }
3313 EXPORT_SYMBOL(kernel_setsockopt);
3314 
3315 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
3316 		    size_t size, int flags)
3317 {
3318 	if (sock->ops->sendpage)
3319 		return sock->ops->sendpage(sock, page, offset, size, flags);
3320 
3321 	return sock_no_sendpage(sock, page, offset, size, flags);
3322 }
3323 EXPORT_SYMBOL(kernel_sendpage);
3324 
3325 int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
3326 			   size_t size, int flags)
3327 {
3328 	struct socket *sock = sk->sk_socket;
3329 
3330 	if (sock->ops->sendpage_locked)
3331 		return sock->ops->sendpage_locked(sk, page, offset, size,
3332 						  flags);
3333 
3334 	return sock_no_sendpage_locked(sk, page, offset, size, flags);
3335 }
3336 EXPORT_SYMBOL(kernel_sendpage_locked);
3337 
3338 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
3339 {
3340 	return sock->ops->shutdown(sock, how);
3341 }
3342 EXPORT_SYMBOL(kernel_sock_shutdown);
3343 
3344 /* This routine returns the IP overhead imposed by a socket i.e.
3345  * the length of the underlying IP header, depending on whether
3346  * this is an IPv4 or IPv6 socket and the length from IP options turned
3347  * on at the socket. Assumes that the caller has a lock on the socket.
3348  */
3349 u32 kernel_sock_ip_overhead(struct sock *sk)
3350 {
3351 	struct inet_sock *inet;
3352 	struct ip_options_rcu *opt;
3353 	u32 overhead = 0;
3354 #if IS_ENABLED(CONFIG_IPV6)
3355 	struct ipv6_pinfo *np;
3356 	struct ipv6_txoptions *optv6 = NULL;
3357 #endif /* IS_ENABLED(CONFIG_IPV6) */
3358 
3359 	if (!sk)
3360 		return overhead;
3361 
3362 	switch (sk->sk_family) {
3363 	case AF_INET:
3364 		inet = inet_sk(sk);
3365 		overhead += sizeof(struct iphdr);
3366 		opt = rcu_dereference_protected(inet->inet_opt,
3367 						sock_owned_by_user(sk));
3368 		if (opt)
3369 			overhead += opt->opt.optlen;
3370 		return overhead;
3371 #if IS_ENABLED(CONFIG_IPV6)
3372 	case AF_INET6:
3373 		np = inet6_sk(sk);
3374 		overhead += sizeof(struct ipv6hdr);
3375 		if (np)
3376 			optv6 = rcu_dereference_protected(np->opt,
3377 							  sock_owned_by_user(sk));
3378 		if (optv6)
3379 			overhead += (optv6->opt_flen + optv6->opt_nflen);
3380 		return overhead;
3381 #endif /* IS_ENABLED(CONFIG_IPV6) */
3382 	default: /* Returns 0 overhead if the socket is not ipv4 or ipv6 */
3383 		return overhead;
3384 	}
3385 }
3386 EXPORT_SYMBOL(kernel_sock_ip_overhead);
3387