xref: /openbmc/linux/net/socket.c (revision c0e297dc)
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 
93 #include <asm/uaccess.h>
94 #include <asm/unistd.h>
95 
96 #include <net/compat.h>
97 #include <net/wext.h>
98 #include <net/cls_cgroup.h>
99 
100 #include <net/sock.h>
101 #include <linux/netfilter.h>
102 
103 #include <linux/if_tun.h>
104 #include <linux/ipv6_route.h>
105 #include <linux/route.h>
106 #include <linux/sockios.h>
107 #include <linux/atalk.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 unsigned int 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  *	Statistics counters of the socket lists
167  */
168 
169 static DEFINE_PER_CPU(int, sockets_in_use);
170 
171 /*
172  * Support routines.
173  * Move socket addresses back and forth across the kernel/user
174  * divide and look after the messy bits.
175  */
176 
177 /**
178  *	move_addr_to_kernel	-	copy a socket address into kernel space
179  *	@uaddr: Address in user space
180  *	@kaddr: Address in kernel space
181  *	@ulen: Length in user space
182  *
183  *	The address is copied into kernel space. If the provided address is
184  *	too long an error code of -EINVAL is returned. If the copy gives
185  *	invalid addresses -EFAULT is returned. On a success 0 is returned.
186  */
187 
188 int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
189 {
190 	if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
191 		return -EINVAL;
192 	if (ulen == 0)
193 		return 0;
194 	if (copy_from_user(kaddr, uaddr, ulen))
195 		return -EFAULT;
196 	return audit_sockaddr(ulen, kaddr);
197 }
198 
199 /**
200  *	move_addr_to_user	-	copy an address to user space
201  *	@kaddr: kernel space address
202  *	@klen: length of address in kernel
203  *	@uaddr: user space address
204  *	@ulen: pointer to user length field
205  *
206  *	The value pointed to by ulen on entry is the buffer length available.
207  *	This is overwritten with the buffer space used. -EINVAL is returned
208  *	if an overlong buffer is specified or a negative buffer size. -EFAULT
209  *	is returned if either the buffer or the length field are not
210  *	accessible.
211  *	After copying the data up to the limit the user specifies, the true
212  *	length of the data is written over the length limit the user
213  *	specified. Zero is returned for a success.
214  */
215 
216 static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
217 			     void __user *uaddr, int __user *ulen)
218 {
219 	int err;
220 	int len;
221 
222 	BUG_ON(klen > sizeof(struct sockaddr_storage));
223 	err = get_user(len, ulen);
224 	if (err)
225 		return err;
226 	if (len > klen)
227 		len = klen;
228 	if (len < 0)
229 		return -EINVAL;
230 	if (len) {
231 		if (audit_sockaddr(klen, kaddr))
232 			return -ENOMEM;
233 		if (copy_to_user(uaddr, kaddr, len))
234 			return -EFAULT;
235 	}
236 	/*
237 	 *      "fromlen shall refer to the value before truncation.."
238 	 *                      1003.1g
239 	 */
240 	return __put_user(klen, ulen);
241 }
242 
243 static struct kmem_cache *sock_inode_cachep __read_mostly;
244 
245 static struct inode *sock_alloc_inode(struct super_block *sb)
246 {
247 	struct socket_alloc *ei;
248 	struct socket_wq *wq;
249 
250 	ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
251 	if (!ei)
252 		return NULL;
253 	wq = kmalloc(sizeof(*wq), GFP_KERNEL);
254 	if (!wq) {
255 		kmem_cache_free(sock_inode_cachep, ei);
256 		return NULL;
257 	}
258 	init_waitqueue_head(&wq->wait);
259 	wq->fasync_list = NULL;
260 	RCU_INIT_POINTER(ei->socket.wq, wq);
261 
262 	ei->socket.state = SS_UNCONNECTED;
263 	ei->socket.flags = 0;
264 	ei->socket.ops = NULL;
265 	ei->socket.sk = NULL;
266 	ei->socket.file = NULL;
267 
268 	return &ei->vfs_inode;
269 }
270 
271 static void sock_destroy_inode(struct inode *inode)
272 {
273 	struct socket_alloc *ei;
274 	struct socket_wq *wq;
275 
276 	ei = container_of(inode, struct socket_alloc, vfs_inode);
277 	wq = rcu_dereference_protected(ei->socket.wq, 1);
278 	kfree_rcu(wq, rcu);
279 	kmem_cache_free(sock_inode_cachep, ei);
280 }
281 
282 static void init_once(void *foo)
283 {
284 	struct socket_alloc *ei = (struct socket_alloc *)foo;
285 
286 	inode_init_once(&ei->vfs_inode);
287 }
288 
289 static int init_inodecache(void)
290 {
291 	sock_inode_cachep = kmem_cache_create("sock_inode_cache",
292 					      sizeof(struct socket_alloc),
293 					      0,
294 					      (SLAB_HWCACHE_ALIGN |
295 					       SLAB_RECLAIM_ACCOUNT |
296 					       SLAB_MEM_SPREAD),
297 					      init_once);
298 	if (sock_inode_cachep == NULL)
299 		return -ENOMEM;
300 	return 0;
301 }
302 
303 static const struct super_operations sockfs_ops = {
304 	.alloc_inode	= sock_alloc_inode,
305 	.destroy_inode	= sock_destroy_inode,
306 	.statfs		= simple_statfs,
307 };
308 
309 /*
310  * sockfs_dname() is called from d_path().
311  */
312 static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
313 {
314 	return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",
315 				d_inode(dentry)->i_ino);
316 }
317 
318 static const struct dentry_operations sockfs_dentry_operations = {
319 	.d_dname  = sockfs_dname,
320 };
321 
322 static struct dentry *sockfs_mount(struct file_system_type *fs_type,
323 			 int flags, const char *dev_name, void *data)
324 {
325 	return mount_pseudo(fs_type, "socket:", &sockfs_ops,
326 		&sockfs_dentry_operations, SOCKFS_MAGIC);
327 }
328 
329 static struct vfsmount *sock_mnt __read_mostly;
330 
331 static struct file_system_type sock_fs_type = {
332 	.name =		"sockfs",
333 	.mount =	sockfs_mount,
334 	.kill_sb =	kill_anon_super,
335 };
336 
337 /*
338  *	Obtains the first available file descriptor and sets it up for use.
339  *
340  *	These functions create file structures and maps them to fd space
341  *	of the current process. On success it returns file descriptor
342  *	and file struct implicitly stored in sock->file.
343  *	Note that another thread may close file descriptor before we return
344  *	from this function. We use the fact that now we do not refer
345  *	to socket after mapping. If one day we will need it, this
346  *	function will increment ref. count on file by 1.
347  *
348  *	In any case returned fd MAY BE not valid!
349  *	This race condition is unavoidable
350  *	with shared fd spaces, we cannot solve it inside kernel,
351  *	but we take care of internal coherence yet.
352  */
353 
354 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
355 {
356 	struct qstr name = { .name = "" };
357 	struct path path;
358 	struct file *file;
359 
360 	if (dname) {
361 		name.name = dname;
362 		name.len = strlen(name.name);
363 	} else if (sock->sk) {
364 		name.name = sock->sk->sk_prot_creator->name;
365 		name.len = strlen(name.name);
366 	}
367 	path.dentry = d_alloc_pseudo(sock_mnt->mnt_sb, &name);
368 	if (unlikely(!path.dentry))
369 		return ERR_PTR(-ENOMEM);
370 	path.mnt = mntget(sock_mnt);
371 
372 	d_instantiate(path.dentry, SOCK_INODE(sock));
373 
374 	file = alloc_file(&path, FMODE_READ | FMODE_WRITE,
375 		  &socket_file_ops);
376 	if (unlikely(IS_ERR(file))) {
377 		/* drop dentry, keep inode */
378 		ihold(d_inode(path.dentry));
379 		path_put(&path);
380 		return file;
381 	}
382 
383 	sock->file = file;
384 	file->f_flags = O_RDWR | (flags & O_NONBLOCK);
385 	file->private_data = sock;
386 	return file;
387 }
388 EXPORT_SYMBOL(sock_alloc_file);
389 
390 static int sock_map_fd(struct socket *sock, int flags)
391 {
392 	struct file *newfile;
393 	int fd = get_unused_fd_flags(flags);
394 	if (unlikely(fd < 0))
395 		return fd;
396 
397 	newfile = sock_alloc_file(sock, flags, NULL);
398 	if (likely(!IS_ERR(newfile))) {
399 		fd_install(fd, newfile);
400 		return fd;
401 	}
402 
403 	put_unused_fd(fd);
404 	return PTR_ERR(newfile);
405 }
406 
407 struct socket *sock_from_file(struct file *file, int *err)
408 {
409 	if (file->f_op == &socket_file_ops)
410 		return file->private_data;	/* set in sock_map_fd */
411 
412 	*err = -ENOTSOCK;
413 	return NULL;
414 }
415 EXPORT_SYMBOL(sock_from_file);
416 
417 /**
418  *	sockfd_lookup - Go from a file number to its socket slot
419  *	@fd: file handle
420  *	@err: pointer to an error code return
421  *
422  *	The file handle passed in is locked and the socket it is bound
423  *	too is returned. If an error occurs the err pointer is overwritten
424  *	with a negative errno code and NULL is returned. The function checks
425  *	for both invalid handles and passing a handle which is not a socket.
426  *
427  *	On a success the socket object pointer is returned.
428  */
429 
430 struct socket *sockfd_lookup(int fd, int *err)
431 {
432 	struct file *file;
433 	struct socket *sock;
434 
435 	file = fget(fd);
436 	if (!file) {
437 		*err = -EBADF;
438 		return NULL;
439 	}
440 
441 	sock = sock_from_file(file, err);
442 	if (!sock)
443 		fput(file);
444 	return sock;
445 }
446 EXPORT_SYMBOL(sockfd_lookup);
447 
448 static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
449 {
450 	struct fd f = fdget(fd);
451 	struct socket *sock;
452 
453 	*err = -EBADF;
454 	if (f.file) {
455 		sock = sock_from_file(f.file, err);
456 		if (likely(sock)) {
457 			*fput_needed = f.flags;
458 			return sock;
459 		}
460 		fdput(f);
461 	}
462 	return NULL;
463 }
464 
465 #define XATTR_SOCKPROTONAME_SUFFIX "sockprotoname"
466 #define XATTR_NAME_SOCKPROTONAME (XATTR_SYSTEM_PREFIX XATTR_SOCKPROTONAME_SUFFIX)
467 #define XATTR_NAME_SOCKPROTONAME_LEN (sizeof(XATTR_NAME_SOCKPROTONAME)-1)
468 static ssize_t sockfs_getxattr(struct dentry *dentry,
469 			       const char *name, void *value, size_t size)
470 {
471 	const char *proto_name;
472 	size_t proto_size;
473 	int error;
474 
475 	error = -ENODATA;
476 	if (!strncmp(name, XATTR_NAME_SOCKPROTONAME, XATTR_NAME_SOCKPROTONAME_LEN)) {
477 		proto_name = dentry->d_name.name;
478 		proto_size = strlen(proto_name);
479 
480 		if (value) {
481 			error = -ERANGE;
482 			if (proto_size + 1 > size)
483 				goto out;
484 
485 			strncpy(value, proto_name, proto_size + 1);
486 		}
487 		error = proto_size + 1;
488 	}
489 
490 out:
491 	return error;
492 }
493 
494 static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
495 				size_t size)
496 {
497 	ssize_t len;
498 	ssize_t used = 0;
499 
500 	len = security_inode_listsecurity(d_inode(dentry), buffer, size);
501 	if (len < 0)
502 		return len;
503 	used += len;
504 	if (buffer) {
505 		if (size < used)
506 			return -ERANGE;
507 		buffer += len;
508 	}
509 
510 	len = (XATTR_NAME_SOCKPROTONAME_LEN + 1);
511 	used += len;
512 	if (buffer) {
513 		if (size < used)
514 			return -ERANGE;
515 		memcpy(buffer, XATTR_NAME_SOCKPROTONAME, len);
516 		buffer += len;
517 	}
518 
519 	return used;
520 }
521 
522 static const struct inode_operations sockfs_inode_ops = {
523 	.getxattr = sockfs_getxattr,
524 	.listxattr = sockfs_listxattr,
525 };
526 
527 /**
528  *	sock_alloc	-	allocate a socket
529  *
530  *	Allocate a new inode and socket object. The two are bound together
531  *	and initialised. The socket is then returned. If we are out of inodes
532  *	NULL is returned.
533  */
534 
535 static struct socket *sock_alloc(void)
536 {
537 	struct inode *inode;
538 	struct socket *sock;
539 
540 	inode = new_inode_pseudo(sock_mnt->mnt_sb);
541 	if (!inode)
542 		return NULL;
543 
544 	sock = SOCKET_I(inode);
545 
546 	kmemcheck_annotate_bitfield(sock, type);
547 	inode->i_ino = get_next_ino();
548 	inode->i_mode = S_IFSOCK | S_IRWXUGO;
549 	inode->i_uid = current_fsuid();
550 	inode->i_gid = current_fsgid();
551 	inode->i_op = &sockfs_inode_ops;
552 
553 	this_cpu_add(sockets_in_use, 1);
554 	return sock;
555 }
556 
557 /**
558  *	sock_release	-	close a socket
559  *	@sock: socket to close
560  *
561  *	The socket is released from the protocol stack if it has a release
562  *	callback, and the inode is then released if the socket is bound to
563  *	an inode not a file.
564  */
565 
566 void sock_release(struct socket *sock)
567 {
568 	if (sock->ops) {
569 		struct module *owner = sock->ops->owner;
570 
571 		sock->ops->release(sock);
572 		sock->ops = NULL;
573 		module_put(owner);
574 	}
575 
576 	if (rcu_dereference_protected(sock->wq, 1)->fasync_list)
577 		pr_err("%s: fasync list not empty!\n", __func__);
578 
579 	this_cpu_sub(sockets_in_use, 1);
580 	if (!sock->file) {
581 		iput(SOCK_INODE(sock));
582 		return;
583 	}
584 	sock->file = NULL;
585 }
586 EXPORT_SYMBOL(sock_release);
587 
588 void __sock_tx_timestamp(const struct sock *sk, __u8 *tx_flags)
589 {
590 	u8 flags = *tx_flags;
591 
592 	if (sk->sk_tsflags & SOF_TIMESTAMPING_TX_HARDWARE)
593 		flags |= SKBTX_HW_TSTAMP;
594 
595 	if (sk->sk_tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)
596 		flags |= SKBTX_SW_TSTAMP;
597 
598 	if (sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED)
599 		flags |= SKBTX_SCHED_TSTAMP;
600 
601 	if (sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK)
602 		flags |= SKBTX_ACK_TSTAMP;
603 
604 	*tx_flags = flags;
605 }
606 EXPORT_SYMBOL(__sock_tx_timestamp);
607 
608 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
609 {
610 	int ret = sock->ops->sendmsg(sock, msg, msg_data_left(msg));
611 	BUG_ON(ret == -EIOCBQUEUED);
612 	return ret;
613 }
614 
615 int sock_sendmsg(struct socket *sock, struct msghdr *msg)
616 {
617 	int err = security_socket_sendmsg(sock, msg,
618 					  msg_data_left(msg));
619 
620 	return err ?: sock_sendmsg_nosec(sock, msg);
621 }
622 EXPORT_SYMBOL(sock_sendmsg);
623 
624 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
625 		   struct kvec *vec, size_t num, size_t size)
626 {
627 	iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
628 	return sock_sendmsg(sock, msg);
629 }
630 EXPORT_SYMBOL(kernel_sendmsg);
631 
632 /*
633  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
634  */
635 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
636 	struct sk_buff *skb)
637 {
638 	int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
639 	struct scm_timestamping tss;
640 	int empty = 1;
641 	struct skb_shared_hwtstamps *shhwtstamps =
642 		skb_hwtstamps(skb);
643 
644 	/* Race occurred between timestamp enabling and packet
645 	   receiving.  Fill in the current time for now. */
646 	if (need_software_tstamp && skb->tstamp.tv64 == 0)
647 		__net_timestamp(skb);
648 
649 	if (need_software_tstamp) {
650 		if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
651 			struct timeval tv;
652 			skb_get_timestamp(skb, &tv);
653 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP,
654 				 sizeof(tv), &tv);
655 		} else {
656 			struct timespec ts;
657 			skb_get_timestampns(skb, &ts);
658 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPNS,
659 				 sizeof(ts), &ts);
660 		}
661 	}
662 
663 	memset(&tss, 0, sizeof(tss));
664 	if ((sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
665 	    ktime_to_timespec_cond(skb->tstamp, tss.ts + 0))
666 		empty = 0;
667 	if (shhwtstamps &&
668 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
669 	    ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2))
670 		empty = 0;
671 	if (!empty)
672 		put_cmsg(msg, SOL_SOCKET,
673 			 SCM_TIMESTAMPING, sizeof(tss), &tss);
674 }
675 EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
676 
677 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
678 	struct sk_buff *skb)
679 {
680 	int ack;
681 
682 	if (!sock_flag(sk, SOCK_WIFI_STATUS))
683 		return;
684 	if (!skb->wifi_acked_valid)
685 		return;
686 
687 	ack = skb->wifi_acked;
688 
689 	put_cmsg(msg, SOL_SOCKET, SCM_WIFI_STATUS, sizeof(ack), &ack);
690 }
691 EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
692 
693 static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
694 				   struct sk_buff *skb)
695 {
696 	if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
697 		put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
698 			sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
699 }
700 
701 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
702 	struct sk_buff *skb)
703 {
704 	sock_recv_timestamp(msg, sk, skb);
705 	sock_recv_drops(msg, sk, skb);
706 }
707 EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops);
708 
709 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
710 				     size_t size, int flags)
711 {
712 	return sock->ops->recvmsg(sock, msg, size, flags);
713 }
714 
715 int sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
716 		 int flags)
717 {
718 	int err = security_socket_recvmsg(sock, msg, size, flags);
719 
720 	return err ?: sock_recvmsg_nosec(sock, msg, size, flags);
721 }
722 EXPORT_SYMBOL(sock_recvmsg);
723 
724 /**
725  * kernel_recvmsg - Receive a message from a socket (kernel space)
726  * @sock:       The socket to receive the message from
727  * @msg:        Received message
728  * @vec:        Input s/g array for message data
729  * @num:        Size of input s/g array
730  * @size:       Number of bytes to read
731  * @flags:      Message flags (MSG_DONTWAIT, etc...)
732  *
733  * On return the msg structure contains the scatter/gather array passed in the
734  * vec argument. The array is modified so that it consists of the unfilled
735  * portion of the original array.
736  *
737  * The returned value is the total number of bytes received, or an error.
738  */
739 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
740 		   struct kvec *vec, size_t num, size_t size, int flags)
741 {
742 	mm_segment_t oldfs = get_fs();
743 	int result;
744 
745 	iov_iter_kvec(&msg->msg_iter, READ | ITER_KVEC, vec, num, size);
746 	set_fs(KERNEL_DS);
747 	result = sock_recvmsg(sock, msg, size, flags);
748 	set_fs(oldfs);
749 	return result;
750 }
751 EXPORT_SYMBOL(kernel_recvmsg);
752 
753 static ssize_t sock_sendpage(struct file *file, struct page *page,
754 			     int offset, size_t size, loff_t *ppos, int more)
755 {
756 	struct socket *sock;
757 	int flags;
758 
759 	sock = file->private_data;
760 
761 	flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
762 	/* more is a combination of MSG_MORE and MSG_SENDPAGE_NOTLAST */
763 	flags |= more;
764 
765 	return kernel_sendpage(sock, page, offset, size, flags);
766 }
767 
768 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
769 				struct pipe_inode_info *pipe, size_t len,
770 				unsigned int flags)
771 {
772 	struct socket *sock = file->private_data;
773 
774 	if (unlikely(!sock->ops->splice_read))
775 		return -EINVAL;
776 
777 	return sock->ops->splice_read(sock, ppos, pipe, len, flags);
778 }
779 
780 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
781 {
782 	struct file *file = iocb->ki_filp;
783 	struct socket *sock = file->private_data;
784 	struct msghdr msg = {.msg_iter = *to,
785 			     .msg_iocb = iocb};
786 	ssize_t res;
787 
788 	if (file->f_flags & O_NONBLOCK)
789 		msg.msg_flags = MSG_DONTWAIT;
790 
791 	if (iocb->ki_pos != 0)
792 		return -ESPIPE;
793 
794 	if (!iov_iter_count(to))	/* Match SYS5 behaviour */
795 		return 0;
796 
797 	res = sock_recvmsg(sock, &msg, iov_iter_count(to), msg.msg_flags);
798 	*to = msg.msg_iter;
799 	return res;
800 }
801 
802 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
803 {
804 	struct file *file = iocb->ki_filp;
805 	struct socket *sock = file->private_data;
806 	struct msghdr msg = {.msg_iter = *from,
807 			     .msg_iocb = iocb};
808 	ssize_t res;
809 
810 	if (iocb->ki_pos != 0)
811 		return -ESPIPE;
812 
813 	if (file->f_flags & O_NONBLOCK)
814 		msg.msg_flags = MSG_DONTWAIT;
815 
816 	if (sock->type == SOCK_SEQPACKET)
817 		msg.msg_flags |= MSG_EOR;
818 
819 	res = sock_sendmsg(sock, &msg);
820 	*from = msg.msg_iter;
821 	return res;
822 }
823 
824 /*
825  * Atomic setting of ioctl hooks to avoid race
826  * with module unload.
827  */
828 
829 static DEFINE_MUTEX(br_ioctl_mutex);
830 static int (*br_ioctl_hook) (struct net *, unsigned int cmd, void __user *arg);
831 
832 void brioctl_set(int (*hook) (struct net *, unsigned int, void __user *))
833 {
834 	mutex_lock(&br_ioctl_mutex);
835 	br_ioctl_hook = hook;
836 	mutex_unlock(&br_ioctl_mutex);
837 }
838 EXPORT_SYMBOL(brioctl_set);
839 
840 static DEFINE_MUTEX(vlan_ioctl_mutex);
841 static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
842 
843 void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
844 {
845 	mutex_lock(&vlan_ioctl_mutex);
846 	vlan_ioctl_hook = hook;
847 	mutex_unlock(&vlan_ioctl_mutex);
848 }
849 EXPORT_SYMBOL(vlan_ioctl_set);
850 
851 static DEFINE_MUTEX(dlci_ioctl_mutex);
852 static int (*dlci_ioctl_hook) (unsigned int, void __user *);
853 
854 void dlci_ioctl_set(int (*hook) (unsigned int, void __user *))
855 {
856 	mutex_lock(&dlci_ioctl_mutex);
857 	dlci_ioctl_hook = hook;
858 	mutex_unlock(&dlci_ioctl_mutex);
859 }
860 EXPORT_SYMBOL(dlci_ioctl_set);
861 
862 static long sock_do_ioctl(struct net *net, struct socket *sock,
863 				 unsigned int cmd, unsigned long arg)
864 {
865 	int err;
866 	void __user *argp = (void __user *)arg;
867 
868 	err = sock->ops->ioctl(sock, cmd, arg);
869 
870 	/*
871 	 * If this ioctl is unknown try to hand it down
872 	 * to the NIC driver.
873 	 */
874 	if (err == -ENOIOCTLCMD)
875 		err = dev_ioctl(net, cmd, argp);
876 
877 	return err;
878 }
879 
880 /*
881  *	With an ioctl, arg may well be a user mode pointer, but we don't know
882  *	what to do with it - that's up to the protocol still.
883  */
884 
885 static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
886 {
887 	struct socket *sock;
888 	struct sock *sk;
889 	void __user *argp = (void __user *)arg;
890 	int pid, err;
891 	struct net *net;
892 
893 	sock = file->private_data;
894 	sk = sock->sk;
895 	net = sock_net(sk);
896 	if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15)) {
897 		err = dev_ioctl(net, cmd, argp);
898 	} else
899 #ifdef CONFIG_WEXT_CORE
900 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
901 		err = dev_ioctl(net, cmd, argp);
902 	} else
903 #endif
904 		switch (cmd) {
905 		case FIOSETOWN:
906 		case SIOCSPGRP:
907 			err = -EFAULT;
908 			if (get_user(pid, (int __user *)argp))
909 				break;
910 			f_setown(sock->file, pid, 1);
911 			err = 0;
912 			break;
913 		case FIOGETOWN:
914 		case SIOCGPGRP:
915 			err = put_user(f_getown(sock->file),
916 				       (int __user *)argp);
917 			break;
918 		case SIOCGIFBR:
919 		case SIOCSIFBR:
920 		case SIOCBRADDBR:
921 		case SIOCBRDELBR:
922 			err = -ENOPKG;
923 			if (!br_ioctl_hook)
924 				request_module("bridge");
925 
926 			mutex_lock(&br_ioctl_mutex);
927 			if (br_ioctl_hook)
928 				err = br_ioctl_hook(net, cmd, argp);
929 			mutex_unlock(&br_ioctl_mutex);
930 			break;
931 		case SIOCGIFVLAN:
932 		case SIOCSIFVLAN:
933 			err = -ENOPKG;
934 			if (!vlan_ioctl_hook)
935 				request_module("8021q");
936 
937 			mutex_lock(&vlan_ioctl_mutex);
938 			if (vlan_ioctl_hook)
939 				err = vlan_ioctl_hook(net, argp);
940 			mutex_unlock(&vlan_ioctl_mutex);
941 			break;
942 		case SIOCADDDLCI:
943 		case SIOCDELDLCI:
944 			err = -ENOPKG;
945 			if (!dlci_ioctl_hook)
946 				request_module("dlci");
947 
948 			mutex_lock(&dlci_ioctl_mutex);
949 			if (dlci_ioctl_hook)
950 				err = dlci_ioctl_hook(cmd, argp);
951 			mutex_unlock(&dlci_ioctl_mutex);
952 			break;
953 		default:
954 			err = sock_do_ioctl(net, sock, cmd, arg);
955 			break;
956 		}
957 	return err;
958 }
959 
960 int sock_create_lite(int family, int type, int protocol, struct socket **res)
961 {
962 	int err;
963 	struct socket *sock = NULL;
964 
965 	err = security_socket_create(family, type, protocol, 1);
966 	if (err)
967 		goto out;
968 
969 	sock = sock_alloc();
970 	if (!sock) {
971 		err = -ENOMEM;
972 		goto out;
973 	}
974 
975 	sock->type = type;
976 	err = security_socket_post_create(sock, family, type, protocol, 1);
977 	if (err)
978 		goto out_release;
979 
980 out:
981 	*res = sock;
982 	return err;
983 out_release:
984 	sock_release(sock);
985 	sock = NULL;
986 	goto out;
987 }
988 EXPORT_SYMBOL(sock_create_lite);
989 
990 /* No kernel lock held - perfect */
991 static unsigned int sock_poll(struct file *file, poll_table *wait)
992 {
993 	unsigned int busy_flag = 0;
994 	struct socket *sock;
995 
996 	/*
997 	 *      We can't return errors to poll, so it's either yes or no.
998 	 */
999 	sock = file->private_data;
1000 
1001 	if (sk_can_busy_loop(sock->sk)) {
1002 		/* this socket can poll_ll so tell the system call */
1003 		busy_flag = POLL_BUSY_LOOP;
1004 
1005 		/* once, only if requested by syscall */
1006 		if (wait && (wait->_key & POLL_BUSY_LOOP))
1007 			sk_busy_loop(sock->sk, 1);
1008 	}
1009 
1010 	return busy_flag | sock->ops->poll(file, sock, wait);
1011 }
1012 
1013 static int sock_mmap(struct file *file, struct vm_area_struct *vma)
1014 {
1015 	struct socket *sock = file->private_data;
1016 
1017 	return sock->ops->mmap(file, sock, vma);
1018 }
1019 
1020 static int sock_close(struct inode *inode, struct file *filp)
1021 {
1022 	sock_release(SOCKET_I(inode));
1023 	return 0;
1024 }
1025 
1026 /*
1027  *	Update the socket async list
1028  *
1029  *	Fasync_list locking strategy.
1030  *
1031  *	1. fasync_list is modified only under process context socket lock
1032  *	   i.e. under semaphore.
1033  *	2. fasync_list is used under read_lock(&sk->sk_callback_lock)
1034  *	   or under socket lock
1035  */
1036 
1037 static int sock_fasync(int fd, struct file *filp, int on)
1038 {
1039 	struct socket *sock = filp->private_data;
1040 	struct sock *sk = sock->sk;
1041 	struct socket_wq *wq;
1042 
1043 	if (sk == NULL)
1044 		return -EINVAL;
1045 
1046 	lock_sock(sk);
1047 	wq = rcu_dereference_protected(sock->wq, sock_owned_by_user(sk));
1048 	fasync_helper(fd, filp, on, &wq->fasync_list);
1049 
1050 	if (!wq->fasync_list)
1051 		sock_reset_flag(sk, SOCK_FASYNC);
1052 	else
1053 		sock_set_flag(sk, SOCK_FASYNC);
1054 
1055 	release_sock(sk);
1056 	return 0;
1057 }
1058 
1059 /* This function may be called only under socket lock or callback_lock or rcu_lock */
1060 
1061 int sock_wake_async(struct socket *sock, int how, int band)
1062 {
1063 	struct socket_wq *wq;
1064 
1065 	if (!sock)
1066 		return -1;
1067 	rcu_read_lock();
1068 	wq = rcu_dereference(sock->wq);
1069 	if (!wq || !wq->fasync_list) {
1070 		rcu_read_unlock();
1071 		return -1;
1072 	}
1073 	switch (how) {
1074 	case SOCK_WAKE_WAITD:
1075 		if (test_bit(SOCK_ASYNC_WAITDATA, &sock->flags))
1076 			break;
1077 		goto call_kill;
1078 	case SOCK_WAKE_SPACE:
1079 		if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags))
1080 			break;
1081 		/* fall through */
1082 	case SOCK_WAKE_IO:
1083 call_kill:
1084 		kill_fasync(&wq->fasync_list, SIGIO, band);
1085 		break;
1086 	case SOCK_WAKE_URG:
1087 		kill_fasync(&wq->fasync_list, SIGURG, band);
1088 	}
1089 	rcu_read_unlock();
1090 	return 0;
1091 }
1092 EXPORT_SYMBOL(sock_wake_async);
1093 
1094 int __sock_create(struct net *net, int family, int type, int protocol,
1095 			 struct socket **res, int kern)
1096 {
1097 	int err;
1098 	struct socket *sock;
1099 	const struct net_proto_family *pf;
1100 
1101 	/*
1102 	 *      Check protocol is in range
1103 	 */
1104 	if (family < 0 || family >= NPROTO)
1105 		return -EAFNOSUPPORT;
1106 	if (type < 0 || type >= SOCK_MAX)
1107 		return -EINVAL;
1108 
1109 	/* Compatibility.
1110 
1111 	   This uglymoron is moved from INET layer to here to avoid
1112 	   deadlock in module load.
1113 	 */
1114 	if (family == PF_INET && type == SOCK_PACKET) {
1115 		static int warned;
1116 		if (!warned) {
1117 			warned = 1;
1118 			pr_info("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
1119 				current->comm);
1120 		}
1121 		family = PF_PACKET;
1122 	}
1123 
1124 	err = security_socket_create(family, type, protocol, kern);
1125 	if (err)
1126 		return err;
1127 
1128 	/*
1129 	 *	Allocate the socket and allow the family to set things up. if
1130 	 *	the protocol is 0, the family is instructed to select an appropriate
1131 	 *	default.
1132 	 */
1133 	sock = sock_alloc();
1134 	if (!sock) {
1135 		net_warn_ratelimited("socket: no more sockets\n");
1136 		return -ENFILE;	/* Not exactly a match, but its the
1137 				   closest posix thing */
1138 	}
1139 
1140 	sock->type = type;
1141 
1142 #ifdef CONFIG_MODULES
1143 	/* Attempt to load a protocol module if the find failed.
1144 	 *
1145 	 * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
1146 	 * requested real, full-featured networking support upon configuration.
1147 	 * Otherwise module support will break!
1148 	 */
1149 	if (rcu_access_pointer(net_families[family]) == NULL)
1150 		request_module("net-pf-%d", family);
1151 #endif
1152 
1153 	rcu_read_lock();
1154 	pf = rcu_dereference(net_families[family]);
1155 	err = -EAFNOSUPPORT;
1156 	if (!pf)
1157 		goto out_release;
1158 
1159 	/*
1160 	 * We will call the ->create function, that possibly is in a loadable
1161 	 * module, so we have to bump that loadable module refcnt first.
1162 	 */
1163 	if (!try_module_get(pf->owner))
1164 		goto out_release;
1165 
1166 	/* Now protected by module ref count */
1167 	rcu_read_unlock();
1168 
1169 	err = pf->create(net, sock, protocol, kern);
1170 	if (err < 0)
1171 		goto out_module_put;
1172 
1173 	/*
1174 	 * Now to bump the refcnt of the [loadable] module that owns this
1175 	 * socket at sock_release time we decrement its refcnt.
1176 	 */
1177 	if (!try_module_get(sock->ops->owner))
1178 		goto out_module_busy;
1179 
1180 	/*
1181 	 * Now that we're done with the ->create function, the [loadable]
1182 	 * module can have its refcnt decremented
1183 	 */
1184 	module_put(pf->owner);
1185 	err = security_socket_post_create(sock, family, type, protocol, kern);
1186 	if (err)
1187 		goto out_sock_release;
1188 	*res = sock;
1189 
1190 	return 0;
1191 
1192 out_module_busy:
1193 	err = -EAFNOSUPPORT;
1194 out_module_put:
1195 	sock->ops = NULL;
1196 	module_put(pf->owner);
1197 out_sock_release:
1198 	sock_release(sock);
1199 	return err;
1200 
1201 out_release:
1202 	rcu_read_unlock();
1203 	goto out_sock_release;
1204 }
1205 EXPORT_SYMBOL(__sock_create);
1206 
1207 int sock_create(int family, int type, int protocol, struct socket **res)
1208 {
1209 	return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
1210 }
1211 EXPORT_SYMBOL(sock_create);
1212 
1213 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
1214 {
1215 	return __sock_create(net, family, type, protocol, res, 1);
1216 }
1217 EXPORT_SYMBOL(sock_create_kern);
1218 
1219 SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
1220 {
1221 	int retval;
1222 	struct socket *sock;
1223 	int flags;
1224 
1225 	/* Check the SOCK_* constants for consistency.  */
1226 	BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
1227 	BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
1228 	BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
1229 	BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
1230 
1231 	flags = type & ~SOCK_TYPE_MASK;
1232 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1233 		return -EINVAL;
1234 	type &= SOCK_TYPE_MASK;
1235 
1236 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1237 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1238 
1239 	retval = sock_create(family, type, protocol, &sock);
1240 	if (retval < 0)
1241 		goto out;
1242 
1243 	retval = sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
1244 	if (retval < 0)
1245 		goto out_release;
1246 
1247 out:
1248 	/* It may be already another descriptor 8) Not kernel problem. */
1249 	return retval;
1250 
1251 out_release:
1252 	sock_release(sock);
1253 	return retval;
1254 }
1255 
1256 /*
1257  *	Create a pair of connected sockets.
1258  */
1259 
1260 SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
1261 		int __user *, usockvec)
1262 {
1263 	struct socket *sock1, *sock2;
1264 	int fd1, fd2, err;
1265 	struct file *newfile1, *newfile2;
1266 	int flags;
1267 
1268 	flags = type & ~SOCK_TYPE_MASK;
1269 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1270 		return -EINVAL;
1271 	type &= SOCK_TYPE_MASK;
1272 
1273 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1274 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1275 
1276 	/*
1277 	 * Obtain the first socket and check if the underlying protocol
1278 	 * supports the socketpair call.
1279 	 */
1280 
1281 	err = sock_create(family, type, protocol, &sock1);
1282 	if (err < 0)
1283 		goto out;
1284 
1285 	err = sock_create(family, type, protocol, &sock2);
1286 	if (err < 0)
1287 		goto out_release_1;
1288 
1289 	err = sock1->ops->socketpair(sock1, sock2);
1290 	if (err < 0)
1291 		goto out_release_both;
1292 
1293 	fd1 = get_unused_fd_flags(flags);
1294 	if (unlikely(fd1 < 0)) {
1295 		err = fd1;
1296 		goto out_release_both;
1297 	}
1298 
1299 	fd2 = get_unused_fd_flags(flags);
1300 	if (unlikely(fd2 < 0)) {
1301 		err = fd2;
1302 		goto out_put_unused_1;
1303 	}
1304 
1305 	newfile1 = sock_alloc_file(sock1, flags, NULL);
1306 	if (unlikely(IS_ERR(newfile1))) {
1307 		err = PTR_ERR(newfile1);
1308 		goto out_put_unused_both;
1309 	}
1310 
1311 	newfile2 = sock_alloc_file(sock2, flags, NULL);
1312 	if (IS_ERR(newfile2)) {
1313 		err = PTR_ERR(newfile2);
1314 		goto out_fput_1;
1315 	}
1316 
1317 	err = put_user(fd1, &usockvec[0]);
1318 	if (err)
1319 		goto out_fput_both;
1320 
1321 	err = put_user(fd2, &usockvec[1]);
1322 	if (err)
1323 		goto out_fput_both;
1324 
1325 	audit_fd_pair(fd1, fd2);
1326 
1327 	fd_install(fd1, newfile1);
1328 	fd_install(fd2, newfile2);
1329 	/* fd1 and fd2 may be already another descriptors.
1330 	 * Not kernel problem.
1331 	 */
1332 
1333 	return 0;
1334 
1335 out_fput_both:
1336 	fput(newfile2);
1337 	fput(newfile1);
1338 	put_unused_fd(fd2);
1339 	put_unused_fd(fd1);
1340 	goto out;
1341 
1342 out_fput_1:
1343 	fput(newfile1);
1344 	put_unused_fd(fd2);
1345 	put_unused_fd(fd1);
1346 	sock_release(sock2);
1347 	goto out;
1348 
1349 out_put_unused_both:
1350 	put_unused_fd(fd2);
1351 out_put_unused_1:
1352 	put_unused_fd(fd1);
1353 out_release_both:
1354 	sock_release(sock2);
1355 out_release_1:
1356 	sock_release(sock1);
1357 out:
1358 	return err;
1359 }
1360 
1361 /*
1362  *	Bind a name to a socket. Nothing much to do here since it's
1363  *	the protocol's responsibility to handle the local address.
1364  *
1365  *	We move the socket address to kernel space before we call
1366  *	the protocol layer (having also checked the address is ok).
1367  */
1368 
1369 SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
1370 {
1371 	struct socket *sock;
1372 	struct sockaddr_storage address;
1373 	int err, fput_needed;
1374 
1375 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1376 	if (sock) {
1377 		err = move_addr_to_kernel(umyaddr, addrlen, &address);
1378 		if (err >= 0) {
1379 			err = security_socket_bind(sock,
1380 						   (struct sockaddr *)&address,
1381 						   addrlen);
1382 			if (!err)
1383 				err = sock->ops->bind(sock,
1384 						      (struct sockaddr *)
1385 						      &address, addrlen);
1386 		}
1387 		fput_light(sock->file, fput_needed);
1388 	}
1389 	return err;
1390 }
1391 
1392 /*
1393  *	Perform a listen. Basically, we allow the protocol to do anything
1394  *	necessary for a listen, and if that works, we mark the socket as
1395  *	ready for listening.
1396  */
1397 
1398 SYSCALL_DEFINE2(listen, int, fd, int, backlog)
1399 {
1400 	struct socket *sock;
1401 	int err, fput_needed;
1402 	int somaxconn;
1403 
1404 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1405 	if (sock) {
1406 		somaxconn = sock_net(sock->sk)->core.sysctl_somaxconn;
1407 		if ((unsigned int)backlog > somaxconn)
1408 			backlog = somaxconn;
1409 
1410 		err = security_socket_listen(sock, backlog);
1411 		if (!err)
1412 			err = sock->ops->listen(sock, backlog);
1413 
1414 		fput_light(sock->file, fput_needed);
1415 	}
1416 	return err;
1417 }
1418 
1419 /*
1420  *	For accept, we attempt to create a new socket, set up the link
1421  *	with the client, wake up the client, then return the new
1422  *	connected fd. We collect the address of the connector in kernel
1423  *	space and move it to user at the very end. This is unclean because
1424  *	we open the socket then return an error.
1425  *
1426  *	1003.1g adds the ability to recvmsg() to query connection pending
1427  *	status to recvmsg. We need to add that support in a way thats
1428  *	clean when we restucture accept also.
1429  */
1430 
1431 SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
1432 		int __user *, upeer_addrlen, int, flags)
1433 {
1434 	struct socket *sock, *newsock;
1435 	struct file *newfile;
1436 	int err, len, newfd, fput_needed;
1437 	struct sockaddr_storage address;
1438 
1439 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1440 		return -EINVAL;
1441 
1442 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1443 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1444 
1445 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1446 	if (!sock)
1447 		goto out;
1448 
1449 	err = -ENFILE;
1450 	newsock = sock_alloc();
1451 	if (!newsock)
1452 		goto out_put;
1453 
1454 	newsock->type = sock->type;
1455 	newsock->ops = sock->ops;
1456 
1457 	/*
1458 	 * We don't need try_module_get here, as the listening socket (sock)
1459 	 * has the protocol module (sock->ops->owner) held.
1460 	 */
1461 	__module_get(newsock->ops->owner);
1462 
1463 	newfd = get_unused_fd_flags(flags);
1464 	if (unlikely(newfd < 0)) {
1465 		err = newfd;
1466 		sock_release(newsock);
1467 		goto out_put;
1468 	}
1469 	newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);
1470 	if (unlikely(IS_ERR(newfile))) {
1471 		err = PTR_ERR(newfile);
1472 		put_unused_fd(newfd);
1473 		sock_release(newsock);
1474 		goto out_put;
1475 	}
1476 
1477 	err = security_socket_accept(sock, newsock);
1478 	if (err)
1479 		goto out_fd;
1480 
1481 	err = sock->ops->accept(sock, newsock, sock->file->f_flags);
1482 	if (err < 0)
1483 		goto out_fd;
1484 
1485 	if (upeer_sockaddr) {
1486 		if (newsock->ops->getname(newsock, (struct sockaddr *)&address,
1487 					  &len, 2) < 0) {
1488 			err = -ECONNABORTED;
1489 			goto out_fd;
1490 		}
1491 		err = move_addr_to_user(&address,
1492 					len, upeer_sockaddr, upeer_addrlen);
1493 		if (err < 0)
1494 			goto out_fd;
1495 	}
1496 
1497 	/* File flags are not inherited via accept() unlike another OSes. */
1498 
1499 	fd_install(newfd, newfile);
1500 	err = newfd;
1501 
1502 out_put:
1503 	fput_light(sock->file, fput_needed);
1504 out:
1505 	return err;
1506 out_fd:
1507 	fput(newfile);
1508 	put_unused_fd(newfd);
1509 	goto out_put;
1510 }
1511 
1512 SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
1513 		int __user *, upeer_addrlen)
1514 {
1515 	return sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
1516 }
1517 
1518 /*
1519  *	Attempt to connect to a socket with the server address.  The address
1520  *	is in user space so we verify it is OK and move it to kernel space.
1521  *
1522  *	For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
1523  *	break bindings
1524  *
1525  *	NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
1526  *	other SEQPACKET protocols that take time to connect() as it doesn't
1527  *	include the -EINPROGRESS status for such sockets.
1528  */
1529 
1530 SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
1531 		int, addrlen)
1532 {
1533 	struct socket *sock;
1534 	struct sockaddr_storage address;
1535 	int err, fput_needed;
1536 
1537 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1538 	if (!sock)
1539 		goto out;
1540 	err = move_addr_to_kernel(uservaddr, addrlen, &address);
1541 	if (err < 0)
1542 		goto out_put;
1543 
1544 	err =
1545 	    security_socket_connect(sock, (struct sockaddr *)&address, addrlen);
1546 	if (err)
1547 		goto out_put;
1548 
1549 	err = sock->ops->connect(sock, (struct sockaddr *)&address, addrlen,
1550 				 sock->file->f_flags);
1551 out_put:
1552 	fput_light(sock->file, fput_needed);
1553 out:
1554 	return err;
1555 }
1556 
1557 /*
1558  *	Get the local address ('name') of a socket object. Move the obtained
1559  *	name to user space.
1560  */
1561 
1562 SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
1563 		int __user *, usockaddr_len)
1564 {
1565 	struct socket *sock;
1566 	struct sockaddr_storage address;
1567 	int len, err, fput_needed;
1568 
1569 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1570 	if (!sock)
1571 		goto out;
1572 
1573 	err = security_socket_getsockname(sock);
1574 	if (err)
1575 		goto out_put;
1576 
1577 	err = sock->ops->getname(sock, (struct sockaddr *)&address, &len, 0);
1578 	if (err)
1579 		goto out_put;
1580 	err = move_addr_to_user(&address, len, usockaddr, usockaddr_len);
1581 
1582 out_put:
1583 	fput_light(sock->file, fput_needed);
1584 out:
1585 	return err;
1586 }
1587 
1588 /*
1589  *	Get the remote address ('name') of a socket object. Move the obtained
1590  *	name to user space.
1591  */
1592 
1593 SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
1594 		int __user *, usockaddr_len)
1595 {
1596 	struct socket *sock;
1597 	struct sockaddr_storage address;
1598 	int len, err, fput_needed;
1599 
1600 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1601 	if (sock != NULL) {
1602 		err = security_socket_getpeername(sock);
1603 		if (err) {
1604 			fput_light(sock->file, fput_needed);
1605 			return err;
1606 		}
1607 
1608 		err =
1609 		    sock->ops->getname(sock, (struct sockaddr *)&address, &len,
1610 				       1);
1611 		if (!err)
1612 			err = move_addr_to_user(&address, len, usockaddr,
1613 						usockaddr_len);
1614 		fput_light(sock->file, fput_needed);
1615 	}
1616 	return err;
1617 }
1618 
1619 /*
1620  *	Send a datagram to a given address. We move the address into kernel
1621  *	space and check the user space data area is readable before invoking
1622  *	the protocol.
1623  */
1624 
1625 SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
1626 		unsigned int, flags, struct sockaddr __user *, addr,
1627 		int, addr_len)
1628 {
1629 	struct socket *sock;
1630 	struct sockaddr_storage address;
1631 	int err;
1632 	struct msghdr msg;
1633 	struct iovec iov;
1634 	int fput_needed;
1635 
1636 	err = import_single_range(WRITE, buff, len, &iov, &msg.msg_iter);
1637 	if (unlikely(err))
1638 		return err;
1639 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1640 	if (!sock)
1641 		goto out;
1642 
1643 	msg.msg_name = NULL;
1644 	msg.msg_control = NULL;
1645 	msg.msg_controllen = 0;
1646 	msg.msg_namelen = 0;
1647 	if (addr) {
1648 		err = move_addr_to_kernel(addr, addr_len, &address);
1649 		if (err < 0)
1650 			goto out_put;
1651 		msg.msg_name = (struct sockaddr *)&address;
1652 		msg.msg_namelen = addr_len;
1653 	}
1654 	if (sock->file->f_flags & O_NONBLOCK)
1655 		flags |= MSG_DONTWAIT;
1656 	msg.msg_flags = flags;
1657 	err = sock_sendmsg(sock, &msg);
1658 
1659 out_put:
1660 	fput_light(sock->file, fput_needed);
1661 out:
1662 	return err;
1663 }
1664 
1665 /*
1666  *	Send a datagram down a socket.
1667  */
1668 
1669 SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
1670 		unsigned int, flags)
1671 {
1672 	return sys_sendto(fd, buff, len, flags, NULL, 0);
1673 }
1674 
1675 /*
1676  *	Receive a frame from the socket and optionally record the address of the
1677  *	sender. We verify the buffers are writable and if needed move the
1678  *	sender address from kernel to user space.
1679  */
1680 
1681 SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
1682 		unsigned int, flags, struct sockaddr __user *, addr,
1683 		int __user *, addr_len)
1684 {
1685 	struct socket *sock;
1686 	struct iovec iov;
1687 	struct msghdr msg;
1688 	struct sockaddr_storage address;
1689 	int err, err2;
1690 	int fput_needed;
1691 
1692 	err = import_single_range(READ, ubuf, size, &iov, &msg.msg_iter);
1693 	if (unlikely(err))
1694 		return err;
1695 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1696 	if (!sock)
1697 		goto out;
1698 
1699 	msg.msg_control = NULL;
1700 	msg.msg_controllen = 0;
1701 	/* Save some cycles and don't copy the address if not needed */
1702 	msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
1703 	/* We assume all kernel code knows the size of sockaddr_storage */
1704 	msg.msg_namelen = 0;
1705 	if (sock->file->f_flags & O_NONBLOCK)
1706 		flags |= MSG_DONTWAIT;
1707 	err = sock_recvmsg(sock, &msg, iov_iter_count(&msg.msg_iter), flags);
1708 
1709 	if (err >= 0 && addr != NULL) {
1710 		err2 = move_addr_to_user(&address,
1711 					 msg.msg_namelen, addr, addr_len);
1712 		if (err2 < 0)
1713 			err = err2;
1714 	}
1715 
1716 	fput_light(sock->file, fput_needed);
1717 out:
1718 	return err;
1719 }
1720 
1721 /*
1722  *	Receive a datagram from a socket.
1723  */
1724 
1725 SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
1726 		unsigned int, flags)
1727 {
1728 	return sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
1729 }
1730 
1731 /*
1732  *	Set a socket option. Because we don't know the option lengths we have
1733  *	to pass the user mode parameter for the protocols to sort out.
1734  */
1735 
1736 SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
1737 		char __user *, optval, int, optlen)
1738 {
1739 	int err, fput_needed;
1740 	struct socket *sock;
1741 
1742 	if (optlen < 0)
1743 		return -EINVAL;
1744 
1745 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1746 	if (sock != NULL) {
1747 		err = security_socket_setsockopt(sock, level, optname);
1748 		if (err)
1749 			goto out_put;
1750 
1751 		if (level == SOL_SOCKET)
1752 			err =
1753 			    sock_setsockopt(sock, level, optname, optval,
1754 					    optlen);
1755 		else
1756 			err =
1757 			    sock->ops->setsockopt(sock, level, optname, optval,
1758 						  optlen);
1759 out_put:
1760 		fput_light(sock->file, fput_needed);
1761 	}
1762 	return err;
1763 }
1764 
1765 /*
1766  *	Get a socket option. Because we don't know the option lengths we have
1767  *	to pass a user mode parameter for the protocols to sort out.
1768  */
1769 
1770 SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
1771 		char __user *, optval, int __user *, optlen)
1772 {
1773 	int err, fput_needed;
1774 	struct socket *sock;
1775 
1776 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1777 	if (sock != NULL) {
1778 		err = security_socket_getsockopt(sock, level, optname);
1779 		if (err)
1780 			goto out_put;
1781 
1782 		if (level == SOL_SOCKET)
1783 			err =
1784 			    sock_getsockopt(sock, level, optname, optval,
1785 					    optlen);
1786 		else
1787 			err =
1788 			    sock->ops->getsockopt(sock, level, optname, optval,
1789 						  optlen);
1790 out_put:
1791 		fput_light(sock->file, fput_needed);
1792 	}
1793 	return err;
1794 }
1795 
1796 /*
1797  *	Shutdown a socket.
1798  */
1799 
1800 SYSCALL_DEFINE2(shutdown, int, fd, int, how)
1801 {
1802 	int err, fput_needed;
1803 	struct socket *sock;
1804 
1805 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1806 	if (sock != NULL) {
1807 		err = security_socket_shutdown(sock, how);
1808 		if (!err)
1809 			err = sock->ops->shutdown(sock, how);
1810 		fput_light(sock->file, fput_needed);
1811 	}
1812 	return err;
1813 }
1814 
1815 /* A couple of helpful macros for getting the address of the 32/64 bit
1816  * fields which are the same type (int / unsigned) on our platforms.
1817  */
1818 #define COMPAT_MSG(msg, member)	((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
1819 #define COMPAT_NAMELEN(msg)	COMPAT_MSG(msg, msg_namelen)
1820 #define COMPAT_FLAGS(msg)	COMPAT_MSG(msg, msg_flags)
1821 
1822 struct used_address {
1823 	struct sockaddr_storage name;
1824 	unsigned int name_len;
1825 };
1826 
1827 static int copy_msghdr_from_user(struct msghdr *kmsg,
1828 				 struct user_msghdr __user *umsg,
1829 				 struct sockaddr __user **save_addr,
1830 				 struct iovec **iov)
1831 {
1832 	struct sockaddr __user *uaddr;
1833 	struct iovec __user *uiov;
1834 	size_t nr_segs;
1835 	ssize_t err;
1836 
1837 	if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
1838 	    __get_user(uaddr, &umsg->msg_name) ||
1839 	    __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
1840 	    __get_user(uiov, &umsg->msg_iov) ||
1841 	    __get_user(nr_segs, &umsg->msg_iovlen) ||
1842 	    __get_user(kmsg->msg_control, &umsg->msg_control) ||
1843 	    __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
1844 	    __get_user(kmsg->msg_flags, &umsg->msg_flags))
1845 		return -EFAULT;
1846 
1847 	if (!uaddr)
1848 		kmsg->msg_namelen = 0;
1849 
1850 	if (kmsg->msg_namelen < 0)
1851 		return -EINVAL;
1852 
1853 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
1854 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
1855 
1856 	if (save_addr)
1857 		*save_addr = uaddr;
1858 
1859 	if (uaddr && kmsg->msg_namelen) {
1860 		if (!save_addr) {
1861 			err = move_addr_to_kernel(uaddr, kmsg->msg_namelen,
1862 						  kmsg->msg_name);
1863 			if (err < 0)
1864 				return err;
1865 		}
1866 	} else {
1867 		kmsg->msg_name = NULL;
1868 		kmsg->msg_namelen = 0;
1869 	}
1870 
1871 	if (nr_segs > UIO_MAXIOV)
1872 		return -EMSGSIZE;
1873 
1874 	kmsg->msg_iocb = NULL;
1875 
1876 	return import_iovec(save_addr ? READ : WRITE, uiov, nr_segs,
1877 			    UIO_FASTIOV, iov, &kmsg->msg_iter);
1878 }
1879 
1880 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
1881 			 struct msghdr *msg_sys, unsigned int flags,
1882 			 struct used_address *used_address)
1883 {
1884 	struct compat_msghdr __user *msg_compat =
1885 	    (struct compat_msghdr __user *)msg;
1886 	struct sockaddr_storage address;
1887 	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
1888 	unsigned char ctl[sizeof(struct cmsghdr) + 20]
1889 	    __attribute__ ((aligned(sizeof(__kernel_size_t))));
1890 	/* 20 is size of ipv6_pktinfo */
1891 	unsigned char *ctl_buf = ctl;
1892 	int ctl_len;
1893 	ssize_t err;
1894 
1895 	msg_sys->msg_name = &address;
1896 
1897 	if (MSG_CMSG_COMPAT & flags)
1898 		err = get_compat_msghdr(msg_sys, msg_compat, NULL, &iov);
1899 	else
1900 		err = copy_msghdr_from_user(msg_sys, msg, NULL, &iov);
1901 	if (err < 0)
1902 		return err;
1903 
1904 	err = -ENOBUFS;
1905 
1906 	if (msg_sys->msg_controllen > INT_MAX)
1907 		goto out_freeiov;
1908 	ctl_len = msg_sys->msg_controllen;
1909 	if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
1910 		err =
1911 		    cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl,
1912 						     sizeof(ctl));
1913 		if (err)
1914 			goto out_freeiov;
1915 		ctl_buf = msg_sys->msg_control;
1916 		ctl_len = msg_sys->msg_controllen;
1917 	} else if (ctl_len) {
1918 		if (ctl_len > sizeof(ctl)) {
1919 			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
1920 			if (ctl_buf == NULL)
1921 				goto out_freeiov;
1922 		}
1923 		err = -EFAULT;
1924 		/*
1925 		 * Careful! Before this, msg_sys->msg_control contains a user pointer.
1926 		 * Afterwards, it will be a kernel pointer. Thus the compiler-assisted
1927 		 * checking falls down on this.
1928 		 */
1929 		if (copy_from_user(ctl_buf,
1930 				   (void __user __force *)msg_sys->msg_control,
1931 				   ctl_len))
1932 			goto out_freectl;
1933 		msg_sys->msg_control = ctl_buf;
1934 	}
1935 	msg_sys->msg_flags = flags;
1936 
1937 	if (sock->file->f_flags & O_NONBLOCK)
1938 		msg_sys->msg_flags |= MSG_DONTWAIT;
1939 	/*
1940 	 * If this is sendmmsg() and current destination address is same as
1941 	 * previously succeeded address, omit asking LSM's decision.
1942 	 * used_address->name_len is initialized to UINT_MAX so that the first
1943 	 * destination address never matches.
1944 	 */
1945 	if (used_address && msg_sys->msg_name &&
1946 	    used_address->name_len == msg_sys->msg_namelen &&
1947 	    !memcmp(&used_address->name, msg_sys->msg_name,
1948 		    used_address->name_len)) {
1949 		err = sock_sendmsg_nosec(sock, msg_sys);
1950 		goto out_freectl;
1951 	}
1952 	err = sock_sendmsg(sock, msg_sys);
1953 	/*
1954 	 * If this is sendmmsg() and sending to current destination address was
1955 	 * successful, remember it.
1956 	 */
1957 	if (used_address && err >= 0) {
1958 		used_address->name_len = msg_sys->msg_namelen;
1959 		if (msg_sys->msg_name)
1960 			memcpy(&used_address->name, msg_sys->msg_name,
1961 			       used_address->name_len);
1962 	}
1963 
1964 out_freectl:
1965 	if (ctl_buf != ctl)
1966 		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
1967 out_freeiov:
1968 	kfree(iov);
1969 	return err;
1970 }
1971 
1972 /*
1973  *	BSD sendmsg interface
1974  */
1975 
1976 long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned flags)
1977 {
1978 	int fput_needed, err;
1979 	struct msghdr msg_sys;
1980 	struct socket *sock;
1981 
1982 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1983 	if (!sock)
1984 		goto out;
1985 
1986 	err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL);
1987 
1988 	fput_light(sock->file, fput_needed);
1989 out:
1990 	return err;
1991 }
1992 
1993 SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
1994 {
1995 	if (flags & MSG_CMSG_COMPAT)
1996 		return -EINVAL;
1997 	return __sys_sendmsg(fd, msg, flags);
1998 }
1999 
2000 /*
2001  *	Linux sendmmsg interface
2002  */
2003 
2004 int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2005 		   unsigned int flags)
2006 {
2007 	int fput_needed, err, datagrams;
2008 	struct socket *sock;
2009 	struct mmsghdr __user *entry;
2010 	struct compat_mmsghdr __user *compat_entry;
2011 	struct msghdr msg_sys;
2012 	struct used_address used_address;
2013 
2014 	if (vlen > UIO_MAXIOV)
2015 		vlen = UIO_MAXIOV;
2016 
2017 	datagrams = 0;
2018 
2019 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2020 	if (!sock)
2021 		return err;
2022 
2023 	used_address.name_len = UINT_MAX;
2024 	entry = mmsg;
2025 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2026 	err = 0;
2027 
2028 	while (datagrams < vlen) {
2029 		if (MSG_CMSG_COMPAT & flags) {
2030 			err = ___sys_sendmsg(sock, (struct user_msghdr __user *)compat_entry,
2031 					     &msg_sys, flags, &used_address);
2032 			if (err < 0)
2033 				break;
2034 			err = __put_user(err, &compat_entry->msg_len);
2035 			++compat_entry;
2036 		} else {
2037 			err = ___sys_sendmsg(sock,
2038 					     (struct user_msghdr __user *)entry,
2039 					     &msg_sys, flags, &used_address);
2040 			if (err < 0)
2041 				break;
2042 			err = put_user(err, &entry->msg_len);
2043 			++entry;
2044 		}
2045 
2046 		if (err)
2047 			break;
2048 		++datagrams;
2049 	}
2050 
2051 	fput_light(sock->file, fput_needed);
2052 
2053 	/* We only return an error if no datagrams were able to be sent */
2054 	if (datagrams != 0)
2055 		return datagrams;
2056 
2057 	return err;
2058 }
2059 
2060 SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
2061 		unsigned int, vlen, unsigned int, flags)
2062 {
2063 	if (flags & MSG_CMSG_COMPAT)
2064 		return -EINVAL;
2065 	return __sys_sendmmsg(fd, mmsg, vlen, flags);
2066 }
2067 
2068 static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
2069 			 struct msghdr *msg_sys, unsigned int flags, int nosec)
2070 {
2071 	struct compat_msghdr __user *msg_compat =
2072 	    (struct compat_msghdr __user *)msg;
2073 	struct iovec iovstack[UIO_FASTIOV];
2074 	struct iovec *iov = iovstack;
2075 	unsigned long cmsg_ptr;
2076 	int total_len, len;
2077 	ssize_t err;
2078 
2079 	/* kernel mode address */
2080 	struct sockaddr_storage addr;
2081 
2082 	/* user mode address pointers */
2083 	struct sockaddr __user *uaddr;
2084 	int __user *uaddr_len = COMPAT_NAMELEN(msg);
2085 
2086 	msg_sys->msg_name = &addr;
2087 
2088 	if (MSG_CMSG_COMPAT & flags)
2089 		err = get_compat_msghdr(msg_sys, msg_compat, &uaddr, &iov);
2090 	else
2091 		err = copy_msghdr_from_user(msg_sys, msg, &uaddr, &iov);
2092 	if (err < 0)
2093 		return err;
2094 	total_len = iov_iter_count(&msg_sys->msg_iter);
2095 
2096 	cmsg_ptr = (unsigned long)msg_sys->msg_control;
2097 	msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
2098 
2099 	/* We assume all kernel code knows the size of sockaddr_storage */
2100 	msg_sys->msg_namelen = 0;
2101 
2102 	if (sock->file->f_flags & O_NONBLOCK)
2103 		flags |= MSG_DONTWAIT;
2104 	err = (nosec ? sock_recvmsg_nosec : sock_recvmsg)(sock, msg_sys,
2105 							  total_len, flags);
2106 	if (err < 0)
2107 		goto out_freeiov;
2108 	len = err;
2109 
2110 	if (uaddr != NULL) {
2111 		err = move_addr_to_user(&addr,
2112 					msg_sys->msg_namelen, uaddr,
2113 					uaddr_len);
2114 		if (err < 0)
2115 			goto out_freeiov;
2116 	}
2117 	err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
2118 			 COMPAT_FLAGS(msg));
2119 	if (err)
2120 		goto out_freeiov;
2121 	if (MSG_CMSG_COMPAT & flags)
2122 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2123 				 &msg_compat->msg_controllen);
2124 	else
2125 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2126 				 &msg->msg_controllen);
2127 	if (err)
2128 		goto out_freeiov;
2129 	err = len;
2130 
2131 out_freeiov:
2132 	kfree(iov);
2133 	return err;
2134 }
2135 
2136 /*
2137  *	BSD recvmsg interface
2138  */
2139 
2140 long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned flags)
2141 {
2142 	int fput_needed, err;
2143 	struct msghdr msg_sys;
2144 	struct socket *sock;
2145 
2146 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2147 	if (!sock)
2148 		goto out;
2149 
2150 	err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
2151 
2152 	fput_light(sock->file, fput_needed);
2153 out:
2154 	return err;
2155 }
2156 
2157 SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
2158 		unsigned int, flags)
2159 {
2160 	if (flags & MSG_CMSG_COMPAT)
2161 		return -EINVAL;
2162 	return __sys_recvmsg(fd, msg, flags);
2163 }
2164 
2165 /*
2166  *     Linux recvmmsg interface
2167  */
2168 
2169 int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2170 		   unsigned int flags, struct timespec *timeout)
2171 {
2172 	int fput_needed, err, datagrams;
2173 	struct socket *sock;
2174 	struct mmsghdr __user *entry;
2175 	struct compat_mmsghdr __user *compat_entry;
2176 	struct msghdr msg_sys;
2177 	struct timespec end_time;
2178 
2179 	if (timeout &&
2180 	    poll_select_set_timeout(&end_time, timeout->tv_sec,
2181 				    timeout->tv_nsec))
2182 		return -EINVAL;
2183 
2184 	datagrams = 0;
2185 
2186 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2187 	if (!sock)
2188 		return err;
2189 
2190 	err = sock_error(sock->sk);
2191 	if (err)
2192 		goto out_put;
2193 
2194 	entry = mmsg;
2195 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2196 
2197 	while (datagrams < vlen) {
2198 		/*
2199 		 * No need to ask LSM for more than the first datagram.
2200 		 */
2201 		if (MSG_CMSG_COMPAT & flags) {
2202 			err = ___sys_recvmsg(sock, (struct user_msghdr __user *)compat_entry,
2203 					     &msg_sys, flags & ~MSG_WAITFORONE,
2204 					     datagrams);
2205 			if (err < 0)
2206 				break;
2207 			err = __put_user(err, &compat_entry->msg_len);
2208 			++compat_entry;
2209 		} else {
2210 			err = ___sys_recvmsg(sock,
2211 					     (struct user_msghdr __user *)entry,
2212 					     &msg_sys, flags & ~MSG_WAITFORONE,
2213 					     datagrams);
2214 			if (err < 0)
2215 				break;
2216 			err = put_user(err, &entry->msg_len);
2217 			++entry;
2218 		}
2219 
2220 		if (err)
2221 			break;
2222 		++datagrams;
2223 
2224 		/* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */
2225 		if (flags & MSG_WAITFORONE)
2226 			flags |= MSG_DONTWAIT;
2227 
2228 		if (timeout) {
2229 			ktime_get_ts(timeout);
2230 			*timeout = timespec_sub(end_time, *timeout);
2231 			if (timeout->tv_sec < 0) {
2232 				timeout->tv_sec = timeout->tv_nsec = 0;
2233 				break;
2234 			}
2235 
2236 			/* Timeout, return less than vlen datagrams */
2237 			if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
2238 				break;
2239 		}
2240 
2241 		/* Out of band data, return right away */
2242 		if (msg_sys.msg_flags & MSG_OOB)
2243 			break;
2244 	}
2245 
2246 out_put:
2247 	fput_light(sock->file, fput_needed);
2248 
2249 	if (err == 0)
2250 		return datagrams;
2251 
2252 	if (datagrams != 0) {
2253 		/*
2254 		 * We may return less entries than requested (vlen) if the
2255 		 * sock is non block and there aren't enough datagrams...
2256 		 */
2257 		if (err != -EAGAIN) {
2258 			/*
2259 			 * ... or  if recvmsg returns an error after we
2260 			 * received some datagrams, where we record the
2261 			 * error to return on the next call or if the
2262 			 * app asks about it using getsockopt(SO_ERROR).
2263 			 */
2264 			sock->sk->sk_err = -err;
2265 		}
2266 
2267 		return datagrams;
2268 	}
2269 
2270 	return err;
2271 }
2272 
2273 SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
2274 		unsigned int, vlen, unsigned int, flags,
2275 		struct timespec __user *, timeout)
2276 {
2277 	int datagrams;
2278 	struct timespec timeout_sys;
2279 
2280 	if (flags & MSG_CMSG_COMPAT)
2281 		return -EINVAL;
2282 
2283 	if (!timeout)
2284 		return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL);
2285 
2286 	if (copy_from_user(&timeout_sys, timeout, sizeof(timeout_sys)))
2287 		return -EFAULT;
2288 
2289 	datagrams = __sys_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
2290 
2291 	if (datagrams > 0 &&
2292 	    copy_to_user(timeout, &timeout_sys, sizeof(timeout_sys)))
2293 		datagrams = -EFAULT;
2294 
2295 	return datagrams;
2296 }
2297 
2298 #ifdef __ARCH_WANT_SYS_SOCKETCALL
2299 /* Argument list sizes for sys_socketcall */
2300 #define AL(x) ((x) * sizeof(unsigned long))
2301 static const unsigned char nargs[21] = {
2302 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
2303 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
2304 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
2305 	AL(4), AL(5), AL(4)
2306 };
2307 
2308 #undef AL
2309 
2310 /*
2311  *	System call vectors.
2312  *
2313  *	Argument checking cleaned up. Saved 20% in size.
2314  *  This function doesn't need to set the kernel lock because
2315  *  it is set by the callees.
2316  */
2317 
2318 SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
2319 {
2320 	unsigned long a[AUDITSC_ARGS];
2321 	unsigned long a0, a1;
2322 	int err;
2323 	unsigned int len;
2324 
2325 	if (call < 1 || call > SYS_SENDMMSG)
2326 		return -EINVAL;
2327 
2328 	len = nargs[call];
2329 	if (len > sizeof(a))
2330 		return -EINVAL;
2331 
2332 	/* copy_from_user should be SMP safe. */
2333 	if (copy_from_user(a, args, len))
2334 		return -EFAULT;
2335 
2336 	err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
2337 	if (err)
2338 		return err;
2339 
2340 	a0 = a[0];
2341 	a1 = a[1];
2342 
2343 	switch (call) {
2344 	case SYS_SOCKET:
2345 		err = sys_socket(a0, a1, a[2]);
2346 		break;
2347 	case SYS_BIND:
2348 		err = sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
2349 		break;
2350 	case SYS_CONNECT:
2351 		err = sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
2352 		break;
2353 	case SYS_LISTEN:
2354 		err = sys_listen(a0, a1);
2355 		break;
2356 	case SYS_ACCEPT:
2357 		err = sys_accept4(a0, (struct sockaddr __user *)a1,
2358 				  (int __user *)a[2], 0);
2359 		break;
2360 	case SYS_GETSOCKNAME:
2361 		err =
2362 		    sys_getsockname(a0, (struct sockaddr __user *)a1,
2363 				    (int __user *)a[2]);
2364 		break;
2365 	case SYS_GETPEERNAME:
2366 		err =
2367 		    sys_getpeername(a0, (struct sockaddr __user *)a1,
2368 				    (int __user *)a[2]);
2369 		break;
2370 	case SYS_SOCKETPAIR:
2371 		err = sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
2372 		break;
2373 	case SYS_SEND:
2374 		err = sys_send(a0, (void __user *)a1, a[2], a[3]);
2375 		break;
2376 	case SYS_SENDTO:
2377 		err = sys_sendto(a0, (void __user *)a1, a[2], a[3],
2378 				 (struct sockaddr __user *)a[4], a[5]);
2379 		break;
2380 	case SYS_RECV:
2381 		err = sys_recv(a0, (void __user *)a1, a[2], a[3]);
2382 		break;
2383 	case SYS_RECVFROM:
2384 		err = sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2385 				   (struct sockaddr __user *)a[4],
2386 				   (int __user *)a[5]);
2387 		break;
2388 	case SYS_SHUTDOWN:
2389 		err = sys_shutdown(a0, a1);
2390 		break;
2391 	case SYS_SETSOCKOPT:
2392 		err = sys_setsockopt(a0, a1, a[2], (char __user *)a[3], a[4]);
2393 		break;
2394 	case SYS_GETSOCKOPT:
2395 		err =
2396 		    sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
2397 				   (int __user *)a[4]);
2398 		break;
2399 	case SYS_SENDMSG:
2400 		err = sys_sendmsg(a0, (struct user_msghdr __user *)a1, a[2]);
2401 		break;
2402 	case SYS_SENDMMSG:
2403 		err = sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3]);
2404 		break;
2405 	case SYS_RECVMSG:
2406 		err = sys_recvmsg(a0, (struct user_msghdr __user *)a1, a[2]);
2407 		break;
2408 	case SYS_RECVMMSG:
2409 		err = sys_recvmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3],
2410 				   (struct timespec __user *)a[4]);
2411 		break;
2412 	case SYS_ACCEPT4:
2413 		err = sys_accept4(a0, (struct sockaddr __user *)a1,
2414 				  (int __user *)a[2], a[3]);
2415 		break;
2416 	default:
2417 		err = -EINVAL;
2418 		break;
2419 	}
2420 	return err;
2421 }
2422 
2423 #endif				/* __ARCH_WANT_SYS_SOCKETCALL */
2424 
2425 /**
2426  *	sock_register - add a socket protocol handler
2427  *	@ops: description of protocol
2428  *
2429  *	This function is called by a protocol handler that wants to
2430  *	advertise its address family, and have it linked into the
2431  *	socket interface. The value ops->family corresponds to the
2432  *	socket system call protocol family.
2433  */
2434 int sock_register(const struct net_proto_family *ops)
2435 {
2436 	int err;
2437 
2438 	if (ops->family >= NPROTO) {
2439 		pr_crit("protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
2440 		return -ENOBUFS;
2441 	}
2442 
2443 	spin_lock(&net_family_lock);
2444 	if (rcu_dereference_protected(net_families[ops->family],
2445 				      lockdep_is_held(&net_family_lock)))
2446 		err = -EEXIST;
2447 	else {
2448 		rcu_assign_pointer(net_families[ops->family], ops);
2449 		err = 0;
2450 	}
2451 	spin_unlock(&net_family_lock);
2452 
2453 	pr_info("NET: Registered protocol family %d\n", ops->family);
2454 	return err;
2455 }
2456 EXPORT_SYMBOL(sock_register);
2457 
2458 /**
2459  *	sock_unregister - remove a protocol handler
2460  *	@family: protocol family to remove
2461  *
2462  *	This function is called by a protocol handler that wants to
2463  *	remove its address family, and have it unlinked from the
2464  *	new socket creation.
2465  *
2466  *	If protocol handler is a module, then it can use module reference
2467  *	counts to protect against new references. If protocol handler is not
2468  *	a module then it needs to provide its own protection in
2469  *	the ops->create routine.
2470  */
2471 void sock_unregister(int family)
2472 {
2473 	BUG_ON(family < 0 || family >= NPROTO);
2474 
2475 	spin_lock(&net_family_lock);
2476 	RCU_INIT_POINTER(net_families[family], NULL);
2477 	spin_unlock(&net_family_lock);
2478 
2479 	synchronize_rcu();
2480 
2481 	pr_info("NET: Unregistered protocol family %d\n", family);
2482 }
2483 EXPORT_SYMBOL(sock_unregister);
2484 
2485 static int __init sock_init(void)
2486 {
2487 	int err;
2488 	/*
2489 	 *      Initialize the network sysctl infrastructure.
2490 	 */
2491 	err = net_sysctl_init();
2492 	if (err)
2493 		goto out;
2494 
2495 	/*
2496 	 *      Initialize skbuff SLAB cache
2497 	 */
2498 	skb_init();
2499 
2500 	/*
2501 	 *      Initialize the protocols module.
2502 	 */
2503 
2504 	init_inodecache();
2505 
2506 	err = register_filesystem(&sock_fs_type);
2507 	if (err)
2508 		goto out_fs;
2509 	sock_mnt = kern_mount(&sock_fs_type);
2510 	if (IS_ERR(sock_mnt)) {
2511 		err = PTR_ERR(sock_mnt);
2512 		goto out_mount;
2513 	}
2514 
2515 	/* The real protocol initialization is performed in later initcalls.
2516 	 */
2517 
2518 #ifdef CONFIG_NETFILTER
2519 	err = netfilter_init();
2520 	if (err)
2521 		goto out;
2522 #endif
2523 
2524 	ptp_classifier_init();
2525 
2526 out:
2527 	return err;
2528 
2529 out_mount:
2530 	unregister_filesystem(&sock_fs_type);
2531 out_fs:
2532 	goto out;
2533 }
2534 
2535 core_initcall(sock_init);	/* early initcall */
2536 
2537 #ifdef CONFIG_PROC_FS
2538 void socket_seq_show(struct seq_file *seq)
2539 {
2540 	int cpu;
2541 	int counter = 0;
2542 
2543 	for_each_possible_cpu(cpu)
2544 	    counter += per_cpu(sockets_in_use, cpu);
2545 
2546 	/* It can be negative, by the way. 8) */
2547 	if (counter < 0)
2548 		counter = 0;
2549 
2550 	seq_printf(seq, "sockets: used %d\n", counter);
2551 }
2552 #endif				/* CONFIG_PROC_FS */
2553 
2554 #ifdef CONFIG_COMPAT
2555 static int do_siocgstamp(struct net *net, struct socket *sock,
2556 			 unsigned int cmd, void __user *up)
2557 {
2558 	mm_segment_t old_fs = get_fs();
2559 	struct timeval ktv;
2560 	int err;
2561 
2562 	set_fs(KERNEL_DS);
2563 	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&ktv);
2564 	set_fs(old_fs);
2565 	if (!err)
2566 		err = compat_put_timeval(&ktv, up);
2567 
2568 	return err;
2569 }
2570 
2571 static int do_siocgstampns(struct net *net, struct socket *sock,
2572 			   unsigned int cmd, void __user *up)
2573 {
2574 	mm_segment_t old_fs = get_fs();
2575 	struct timespec kts;
2576 	int err;
2577 
2578 	set_fs(KERNEL_DS);
2579 	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&kts);
2580 	set_fs(old_fs);
2581 	if (!err)
2582 		err = compat_put_timespec(&kts, up);
2583 
2584 	return err;
2585 }
2586 
2587 static int dev_ifname32(struct net *net, struct compat_ifreq __user *uifr32)
2588 {
2589 	struct ifreq __user *uifr;
2590 	int err;
2591 
2592 	uifr = compat_alloc_user_space(sizeof(struct ifreq));
2593 	if (copy_in_user(uifr, uifr32, sizeof(struct compat_ifreq)))
2594 		return -EFAULT;
2595 
2596 	err = dev_ioctl(net, SIOCGIFNAME, uifr);
2597 	if (err)
2598 		return err;
2599 
2600 	if (copy_in_user(uifr32, uifr, sizeof(struct compat_ifreq)))
2601 		return -EFAULT;
2602 
2603 	return 0;
2604 }
2605 
2606 static int dev_ifconf(struct net *net, struct compat_ifconf __user *uifc32)
2607 {
2608 	struct compat_ifconf ifc32;
2609 	struct ifconf ifc;
2610 	struct ifconf __user *uifc;
2611 	struct compat_ifreq __user *ifr32;
2612 	struct ifreq __user *ifr;
2613 	unsigned int i, j;
2614 	int err;
2615 
2616 	if (copy_from_user(&ifc32, uifc32, sizeof(struct compat_ifconf)))
2617 		return -EFAULT;
2618 
2619 	memset(&ifc, 0, sizeof(ifc));
2620 	if (ifc32.ifcbuf == 0) {
2621 		ifc32.ifc_len = 0;
2622 		ifc.ifc_len = 0;
2623 		ifc.ifc_req = NULL;
2624 		uifc = compat_alloc_user_space(sizeof(struct ifconf));
2625 	} else {
2626 		size_t len = ((ifc32.ifc_len / sizeof(struct compat_ifreq)) + 1) *
2627 			sizeof(struct ifreq);
2628 		uifc = compat_alloc_user_space(sizeof(struct ifconf) + len);
2629 		ifc.ifc_len = len;
2630 		ifr = ifc.ifc_req = (void __user *)(uifc + 1);
2631 		ifr32 = compat_ptr(ifc32.ifcbuf);
2632 		for (i = 0; i < ifc32.ifc_len; i += sizeof(struct compat_ifreq)) {
2633 			if (copy_in_user(ifr, ifr32, sizeof(struct compat_ifreq)))
2634 				return -EFAULT;
2635 			ifr++;
2636 			ifr32++;
2637 		}
2638 	}
2639 	if (copy_to_user(uifc, &ifc, sizeof(struct ifconf)))
2640 		return -EFAULT;
2641 
2642 	err = dev_ioctl(net, SIOCGIFCONF, uifc);
2643 	if (err)
2644 		return err;
2645 
2646 	if (copy_from_user(&ifc, uifc, sizeof(struct ifconf)))
2647 		return -EFAULT;
2648 
2649 	ifr = ifc.ifc_req;
2650 	ifr32 = compat_ptr(ifc32.ifcbuf);
2651 	for (i = 0, j = 0;
2652 	     i + sizeof(struct compat_ifreq) <= ifc32.ifc_len && j < ifc.ifc_len;
2653 	     i += sizeof(struct compat_ifreq), j += sizeof(struct ifreq)) {
2654 		if (copy_in_user(ifr32, ifr, sizeof(struct compat_ifreq)))
2655 			return -EFAULT;
2656 		ifr32++;
2657 		ifr++;
2658 	}
2659 
2660 	if (ifc32.ifcbuf == 0) {
2661 		/* Translate from 64-bit structure multiple to
2662 		 * a 32-bit one.
2663 		 */
2664 		i = ifc.ifc_len;
2665 		i = ((i / sizeof(struct ifreq)) * sizeof(struct compat_ifreq));
2666 		ifc32.ifc_len = i;
2667 	} else {
2668 		ifc32.ifc_len = i;
2669 	}
2670 	if (copy_to_user(uifc32, &ifc32, sizeof(struct compat_ifconf)))
2671 		return -EFAULT;
2672 
2673 	return 0;
2674 }
2675 
2676 static int ethtool_ioctl(struct net *net, struct compat_ifreq __user *ifr32)
2677 {
2678 	struct compat_ethtool_rxnfc __user *compat_rxnfc;
2679 	bool convert_in = false, convert_out = false;
2680 	size_t buf_size = ALIGN(sizeof(struct ifreq), 8);
2681 	struct ethtool_rxnfc __user *rxnfc;
2682 	struct ifreq __user *ifr;
2683 	u32 rule_cnt = 0, actual_rule_cnt;
2684 	u32 ethcmd;
2685 	u32 data;
2686 	int ret;
2687 
2688 	if (get_user(data, &ifr32->ifr_ifru.ifru_data))
2689 		return -EFAULT;
2690 
2691 	compat_rxnfc = compat_ptr(data);
2692 
2693 	if (get_user(ethcmd, &compat_rxnfc->cmd))
2694 		return -EFAULT;
2695 
2696 	/* Most ethtool structures are defined without padding.
2697 	 * Unfortunately struct ethtool_rxnfc is an exception.
2698 	 */
2699 	switch (ethcmd) {
2700 	default:
2701 		break;
2702 	case ETHTOOL_GRXCLSRLALL:
2703 		/* Buffer size is variable */
2704 		if (get_user(rule_cnt, &compat_rxnfc->rule_cnt))
2705 			return -EFAULT;
2706 		if (rule_cnt > KMALLOC_MAX_SIZE / sizeof(u32))
2707 			return -ENOMEM;
2708 		buf_size += rule_cnt * sizeof(u32);
2709 		/* fall through */
2710 	case ETHTOOL_GRXRINGS:
2711 	case ETHTOOL_GRXCLSRLCNT:
2712 	case ETHTOOL_GRXCLSRULE:
2713 	case ETHTOOL_SRXCLSRLINS:
2714 		convert_out = true;
2715 		/* fall through */
2716 	case ETHTOOL_SRXCLSRLDEL:
2717 		buf_size += sizeof(struct ethtool_rxnfc);
2718 		convert_in = true;
2719 		break;
2720 	}
2721 
2722 	ifr = compat_alloc_user_space(buf_size);
2723 	rxnfc = (void __user *)ifr + ALIGN(sizeof(struct ifreq), 8);
2724 
2725 	if (copy_in_user(&ifr->ifr_name, &ifr32->ifr_name, IFNAMSIZ))
2726 		return -EFAULT;
2727 
2728 	if (put_user(convert_in ? rxnfc : compat_ptr(data),
2729 		     &ifr->ifr_ifru.ifru_data))
2730 		return -EFAULT;
2731 
2732 	if (convert_in) {
2733 		/* We expect there to be holes between fs.m_ext and
2734 		 * fs.ring_cookie and at the end of fs, but nowhere else.
2735 		 */
2736 		BUILD_BUG_ON(offsetof(struct compat_ethtool_rxnfc, fs.m_ext) +
2737 			     sizeof(compat_rxnfc->fs.m_ext) !=
2738 			     offsetof(struct ethtool_rxnfc, fs.m_ext) +
2739 			     sizeof(rxnfc->fs.m_ext));
2740 		BUILD_BUG_ON(
2741 			offsetof(struct compat_ethtool_rxnfc, fs.location) -
2742 			offsetof(struct compat_ethtool_rxnfc, fs.ring_cookie) !=
2743 			offsetof(struct ethtool_rxnfc, fs.location) -
2744 			offsetof(struct ethtool_rxnfc, fs.ring_cookie));
2745 
2746 		if (copy_in_user(rxnfc, compat_rxnfc,
2747 				 (void __user *)(&rxnfc->fs.m_ext + 1) -
2748 				 (void __user *)rxnfc) ||
2749 		    copy_in_user(&rxnfc->fs.ring_cookie,
2750 				 &compat_rxnfc->fs.ring_cookie,
2751 				 (void __user *)(&rxnfc->fs.location + 1) -
2752 				 (void __user *)&rxnfc->fs.ring_cookie) ||
2753 		    copy_in_user(&rxnfc->rule_cnt, &compat_rxnfc->rule_cnt,
2754 				 sizeof(rxnfc->rule_cnt)))
2755 			return -EFAULT;
2756 	}
2757 
2758 	ret = dev_ioctl(net, SIOCETHTOOL, ifr);
2759 	if (ret)
2760 		return ret;
2761 
2762 	if (convert_out) {
2763 		if (copy_in_user(compat_rxnfc, rxnfc,
2764 				 (const void __user *)(&rxnfc->fs.m_ext + 1) -
2765 				 (const void __user *)rxnfc) ||
2766 		    copy_in_user(&compat_rxnfc->fs.ring_cookie,
2767 				 &rxnfc->fs.ring_cookie,
2768 				 (const void __user *)(&rxnfc->fs.location + 1) -
2769 				 (const void __user *)&rxnfc->fs.ring_cookie) ||
2770 		    copy_in_user(&compat_rxnfc->rule_cnt, &rxnfc->rule_cnt,
2771 				 sizeof(rxnfc->rule_cnt)))
2772 			return -EFAULT;
2773 
2774 		if (ethcmd == ETHTOOL_GRXCLSRLALL) {
2775 			/* As an optimisation, we only copy the actual
2776 			 * number of rules that the underlying
2777 			 * function returned.  Since Mallory might
2778 			 * change the rule count in user memory, we
2779 			 * check that it is less than the rule count
2780 			 * originally given (as the user buffer size),
2781 			 * which has been range-checked.
2782 			 */
2783 			if (get_user(actual_rule_cnt, &rxnfc->rule_cnt))
2784 				return -EFAULT;
2785 			if (actual_rule_cnt < rule_cnt)
2786 				rule_cnt = actual_rule_cnt;
2787 			if (copy_in_user(&compat_rxnfc->rule_locs[0],
2788 					 &rxnfc->rule_locs[0],
2789 					 rule_cnt * sizeof(u32)))
2790 				return -EFAULT;
2791 		}
2792 	}
2793 
2794 	return 0;
2795 }
2796 
2797 static int compat_siocwandev(struct net *net, struct compat_ifreq __user *uifr32)
2798 {
2799 	void __user *uptr;
2800 	compat_uptr_t uptr32;
2801 	struct ifreq __user *uifr;
2802 
2803 	uifr = compat_alloc_user_space(sizeof(*uifr));
2804 	if (copy_in_user(uifr, uifr32, sizeof(struct compat_ifreq)))
2805 		return -EFAULT;
2806 
2807 	if (get_user(uptr32, &uifr32->ifr_settings.ifs_ifsu))
2808 		return -EFAULT;
2809 
2810 	uptr = compat_ptr(uptr32);
2811 
2812 	if (put_user(uptr, &uifr->ifr_settings.ifs_ifsu.raw_hdlc))
2813 		return -EFAULT;
2814 
2815 	return dev_ioctl(net, SIOCWANDEV, uifr);
2816 }
2817 
2818 static int bond_ioctl(struct net *net, unsigned int cmd,
2819 			 struct compat_ifreq __user *ifr32)
2820 {
2821 	struct ifreq kifr;
2822 	mm_segment_t old_fs;
2823 	int err;
2824 
2825 	switch (cmd) {
2826 	case SIOCBONDENSLAVE:
2827 	case SIOCBONDRELEASE:
2828 	case SIOCBONDSETHWADDR:
2829 	case SIOCBONDCHANGEACTIVE:
2830 		if (copy_from_user(&kifr, ifr32, sizeof(struct compat_ifreq)))
2831 			return -EFAULT;
2832 
2833 		old_fs = get_fs();
2834 		set_fs(KERNEL_DS);
2835 		err = dev_ioctl(net, cmd,
2836 				(struct ifreq __user __force *) &kifr);
2837 		set_fs(old_fs);
2838 
2839 		return err;
2840 	default:
2841 		return -ENOIOCTLCMD;
2842 	}
2843 }
2844 
2845 /* Handle ioctls that use ifreq::ifr_data and just need struct ifreq converted */
2846 static int compat_ifr_data_ioctl(struct net *net, unsigned int cmd,
2847 				 struct compat_ifreq __user *u_ifreq32)
2848 {
2849 	struct ifreq __user *u_ifreq64;
2850 	char tmp_buf[IFNAMSIZ];
2851 	void __user *data64;
2852 	u32 data32;
2853 
2854 	if (copy_from_user(&tmp_buf[0], &(u_ifreq32->ifr_ifrn.ifrn_name[0]),
2855 			   IFNAMSIZ))
2856 		return -EFAULT;
2857 	if (get_user(data32, &u_ifreq32->ifr_ifru.ifru_data))
2858 		return -EFAULT;
2859 	data64 = compat_ptr(data32);
2860 
2861 	u_ifreq64 = compat_alloc_user_space(sizeof(*u_ifreq64));
2862 
2863 	if (copy_to_user(&u_ifreq64->ifr_ifrn.ifrn_name[0], &tmp_buf[0],
2864 			 IFNAMSIZ))
2865 		return -EFAULT;
2866 	if (put_user(data64, &u_ifreq64->ifr_ifru.ifru_data))
2867 		return -EFAULT;
2868 
2869 	return dev_ioctl(net, cmd, u_ifreq64);
2870 }
2871 
2872 static int dev_ifsioc(struct net *net, struct socket *sock,
2873 			 unsigned int cmd, struct compat_ifreq __user *uifr32)
2874 {
2875 	struct ifreq __user *uifr;
2876 	int err;
2877 
2878 	uifr = compat_alloc_user_space(sizeof(*uifr));
2879 	if (copy_in_user(uifr, uifr32, sizeof(*uifr32)))
2880 		return -EFAULT;
2881 
2882 	err = sock_do_ioctl(net, sock, cmd, (unsigned long)uifr);
2883 
2884 	if (!err) {
2885 		switch (cmd) {
2886 		case SIOCGIFFLAGS:
2887 		case SIOCGIFMETRIC:
2888 		case SIOCGIFMTU:
2889 		case SIOCGIFMEM:
2890 		case SIOCGIFHWADDR:
2891 		case SIOCGIFINDEX:
2892 		case SIOCGIFADDR:
2893 		case SIOCGIFBRDADDR:
2894 		case SIOCGIFDSTADDR:
2895 		case SIOCGIFNETMASK:
2896 		case SIOCGIFPFLAGS:
2897 		case SIOCGIFTXQLEN:
2898 		case SIOCGMIIPHY:
2899 		case SIOCGMIIREG:
2900 			if (copy_in_user(uifr32, uifr, sizeof(*uifr32)))
2901 				err = -EFAULT;
2902 			break;
2903 		}
2904 	}
2905 	return err;
2906 }
2907 
2908 static int compat_sioc_ifmap(struct net *net, unsigned int cmd,
2909 			struct compat_ifreq __user *uifr32)
2910 {
2911 	struct ifreq ifr;
2912 	struct compat_ifmap __user *uifmap32;
2913 	mm_segment_t old_fs;
2914 	int err;
2915 
2916 	uifmap32 = &uifr32->ifr_ifru.ifru_map;
2917 	err = copy_from_user(&ifr, uifr32, sizeof(ifr.ifr_name));
2918 	err |= get_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
2919 	err |= get_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
2920 	err |= get_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
2921 	err |= get_user(ifr.ifr_map.irq, &uifmap32->irq);
2922 	err |= get_user(ifr.ifr_map.dma, &uifmap32->dma);
2923 	err |= get_user(ifr.ifr_map.port, &uifmap32->port);
2924 	if (err)
2925 		return -EFAULT;
2926 
2927 	old_fs = get_fs();
2928 	set_fs(KERNEL_DS);
2929 	err = dev_ioctl(net, cmd, (void  __user __force *)&ifr);
2930 	set_fs(old_fs);
2931 
2932 	if (cmd == SIOCGIFMAP && !err) {
2933 		err = copy_to_user(uifr32, &ifr, sizeof(ifr.ifr_name));
2934 		err |= put_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
2935 		err |= put_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
2936 		err |= put_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
2937 		err |= put_user(ifr.ifr_map.irq, &uifmap32->irq);
2938 		err |= put_user(ifr.ifr_map.dma, &uifmap32->dma);
2939 		err |= put_user(ifr.ifr_map.port, &uifmap32->port);
2940 		if (err)
2941 			err = -EFAULT;
2942 	}
2943 	return err;
2944 }
2945 
2946 struct rtentry32 {
2947 	u32		rt_pad1;
2948 	struct sockaddr rt_dst;         /* target address               */
2949 	struct sockaddr rt_gateway;     /* gateway addr (RTF_GATEWAY)   */
2950 	struct sockaddr rt_genmask;     /* target network mask (IP)     */
2951 	unsigned short	rt_flags;
2952 	short		rt_pad2;
2953 	u32		rt_pad3;
2954 	unsigned char	rt_tos;
2955 	unsigned char	rt_class;
2956 	short		rt_pad4;
2957 	short		rt_metric;      /* +1 for binary compatibility! */
2958 	/* char * */ u32 rt_dev;        /* forcing the device at add    */
2959 	u32		rt_mtu;         /* per route MTU/Window         */
2960 	u32		rt_window;      /* Window clamping              */
2961 	unsigned short  rt_irtt;        /* Initial RTT                  */
2962 };
2963 
2964 struct in6_rtmsg32 {
2965 	struct in6_addr		rtmsg_dst;
2966 	struct in6_addr		rtmsg_src;
2967 	struct in6_addr		rtmsg_gateway;
2968 	u32			rtmsg_type;
2969 	u16			rtmsg_dst_len;
2970 	u16			rtmsg_src_len;
2971 	u32			rtmsg_metric;
2972 	u32			rtmsg_info;
2973 	u32			rtmsg_flags;
2974 	s32			rtmsg_ifindex;
2975 };
2976 
2977 static int routing_ioctl(struct net *net, struct socket *sock,
2978 			 unsigned int cmd, void __user *argp)
2979 {
2980 	int ret;
2981 	void *r = NULL;
2982 	struct in6_rtmsg r6;
2983 	struct rtentry r4;
2984 	char devname[16];
2985 	u32 rtdev;
2986 	mm_segment_t old_fs = get_fs();
2987 
2988 	if (sock && sock->sk && sock->sk->sk_family == AF_INET6) { /* ipv6 */
2989 		struct in6_rtmsg32 __user *ur6 = argp;
2990 		ret = copy_from_user(&r6.rtmsg_dst, &(ur6->rtmsg_dst),
2991 			3 * sizeof(struct in6_addr));
2992 		ret |= get_user(r6.rtmsg_type, &(ur6->rtmsg_type));
2993 		ret |= get_user(r6.rtmsg_dst_len, &(ur6->rtmsg_dst_len));
2994 		ret |= get_user(r6.rtmsg_src_len, &(ur6->rtmsg_src_len));
2995 		ret |= get_user(r6.rtmsg_metric, &(ur6->rtmsg_metric));
2996 		ret |= get_user(r6.rtmsg_info, &(ur6->rtmsg_info));
2997 		ret |= get_user(r6.rtmsg_flags, &(ur6->rtmsg_flags));
2998 		ret |= get_user(r6.rtmsg_ifindex, &(ur6->rtmsg_ifindex));
2999 
3000 		r = (void *) &r6;
3001 	} else { /* ipv4 */
3002 		struct rtentry32 __user *ur4 = argp;
3003 		ret = copy_from_user(&r4.rt_dst, &(ur4->rt_dst),
3004 					3 * sizeof(struct sockaddr));
3005 		ret |= get_user(r4.rt_flags, &(ur4->rt_flags));
3006 		ret |= get_user(r4.rt_metric, &(ur4->rt_metric));
3007 		ret |= get_user(r4.rt_mtu, &(ur4->rt_mtu));
3008 		ret |= get_user(r4.rt_window, &(ur4->rt_window));
3009 		ret |= get_user(r4.rt_irtt, &(ur4->rt_irtt));
3010 		ret |= get_user(rtdev, &(ur4->rt_dev));
3011 		if (rtdev) {
3012 			ret |= copy_from_user(devname, compat_ptr(rtdev), 15);
3013 			r4.rt_dev = (char __user __force *)devname;
3014 			devname[15] = 0;
3015 		} else
3016 			r4.rt_dev = NULL;
3017 
3018 		r = (void *) &r4;
3019 	}
3020 
3021 	if (ret) {
3022 		ret = -EFAULT;
3023 		goto out;
3024 	}
3025 
3026 	set_fs(KERNEL_DS);
3027 	ret = sock_do_ioctl(net, sock, cmd, (unsigned long) r);
3028 	set_fs(old_fs);
3029 
3030 out:
3031 	return ret;
3032 }
3033 
3034 /* Since old style bridge ioctl's endup using SIOCDEVPRIVATE
3035  * for some operations; this forces use of the newer bridge-utils that
3036  * use compatible ioctls
3037  */
3038 static int old_bridge_ioctl(compat_ulong_t __user *argp)
3039 {
3040 	compat_ulong_t tmp;
3041 
3042 	if (get_user(tmp, argp))
3043 		return -EFAULT;
3044 	if (tmp == BRCTL_GET_VERSION)
3045 		return BRCTL_VERSION + 1;
3046 	return -EINVAL;
3047 }
3048 
3049 static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
3050 			 unsigned int cmd, unsigned long arg)
3051 {
3052 	void __user *argp = compat_ptr(arg);
3053 	struct sock *sk = sock->sk;
3054 	struct net *net = sock_net(sk);
3055 
3056 	if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))
3057 		return compat_ifr_data_ioctl(net, cmd, argp);
3058 
3059 	switch (cmd) {
3060 	case SIOCSIFBR:
3061 	case SIOCGIFBR:
3062 		return old_bridge_ioctl(argp);
3063 	case SIOCGIFNAME:
3064 		return dev_ifname32(net, argp);
3065 	case SIOCGIFCONF:
3066 		return dev_ifconf(net, argp);
3067 	case SIOCETHTOOL:
3068 		return ethtool_ioctl(net, argp);
3069 	case SIOCWANDEV:
3070 		return compat_siocwandev(net, argp);
3071 	case SIOCGIFMAP:
3072 	case SIOCSIFMAP:
3073 		return compat_sioc_ifmap(net, cmd, argp);
3074 	case SIOCBONDENSLAVE:
3075 	case SIOCBONDRELEASE:
3076 	case SIOCBONDSETHWADDR:
3077 	case SIOCBONDCHANGEACTIVE:
3078 		return bond_ioctl(net, cmd, argp);
3079 	case SIOCADDRT:
3080 	case SIOCDELRT:
3081 		return routing_ioctl(net, sock, cmd, argp);
3082 	case SIOCGSTAMP:
3083 		return do_siocgstamp(net, sock, cmd, argp);
3084 	case SIOCGSTAMPNS:
3085 		return do_siocgstampns(net, sock, cmd, argp);
3086 	case SIOCBONDSLAVEINFOQUERY:
3087 	case SIOCBONDINFOQUERY:
3088 	case SIOCSHWTSTAMP:
3089 	case SIOCGHWTSTAMP:
3090 		return compat_ifr_data_ioctl(net, cmd, argp);
3091 
3092 	case FIOSETOWN:
3093 	case SIOCSPGRP:
3094 	case FIOGETOWN:
3095 	case SIOCGPGRP:
3096 	case SIOCBRADDBR:
3097 	case SIOCBRDELBR:
3098 	case SIOCGIFVLAN:
3099 	case SIOCSIFVLAN:
3100 	case SIOCADDDLCI:
3101 	case SIOCDELDLCI:
3102 		return sock_ioctl(file, cmd, arg);
3103 
3104 	case SIOCGIFFLAGS:
3105 	case SIOCSIFFLAGS:
3106 	case SIOCGIFMETRIC:
3107 	case SIOCSIFMETRIC:
3108 	case SIOCGIFMTU:
3109 	case SIOCSIFMTU:
3110 	case SIOCGIFMEM:
3111 	case SIOCSIFMEM:
3112 	case SIOCGIFHWADDR:
3113 	case SIOCSIFHWADDR:
3114 	case SIOCADDMULTI:
3115 	case SIOCDELMULTI:
3116 	case SIOCGIFINDEX:
3117 	case SIOCGIFADDR:
3118 	case SIOCSIFADDR:
3119 	case SIOCSIFHWBROADCAST:
3120 	case SIOCDIFADDR:
3121 	case SIOCGIFBRDADDR:
3122 	case SIOCSIFBRDADDR:
3123 	case SIOCGIFDSTADDR:
3124 	case SIOCSIFDSTADDR:
3125 	case SIOCGIFNETMASK:
3126 	case SIOCSIFNETMASK:
3127 	case SIOCSIFPFLAGS:
3128 	case SIOCGIFPFLAGS:
3129 	case SIOCGIFTXQLEN:
3130 	case SIOCSIFTXQLEN:
3131 	case SIOCBRADDIF:
3132 	case SIOCBRDELIF:
3133 	case SIOCSIFNAME:
3134 	case SIOCGMIIPHY:
3135 	case SIOCGMIIREG:
3136 	case SIOCSMIIREG:
3137 		return dev_ifsioc(net, sock, cmd, argp);
3138 
3139 	case SIOCSARP:
3140 	case SIOCGARP:
3141 	case SIOCDARP:
3142 	case SIOCATMARK:
3143 		return sock_do_ioctl(net, sock, cmd, arg);
3144 	}
3145 
3146 	return -ENOIOCTLCMD;
3147 }
3148 
3149 static long compat_sock_ioctl(struct file *file, unsigned int cmd,
3150 			      unsigned long arg)
3151 {
3152 	struct socket *sock = file->private_data;
3153 	int ret = -ENOIOCTLCMD;
3154 	struct sock *sk;
3155 	struct net *net;
3156 
3157 	sk = sock->sk;
3158 	net = sock_net(sk);
3159 
3160 	if (sock->ops->compat_ioctl)
3161 		ret = sock->ops->compat_ioctl(sock, cmd, arg);
3162 
3163 	if (ret == -ENOIOCTLCMD &&
3164 	    (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
3165 		ret = compat_wext_handle_ioctl(net, cmd, arg);
3166 
3167 	if (ret == -ENOIOCTLCMD)
3168 		ret = compat_sock_ioctl_trans(file, sock, cmd, arg);
3169 
3170 	return ret;
3171 }
3172 #endif
3173 
3174 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
3175 {
3176 	return sock->ops->bind(sock, addr, addrlen);
3177 }
3178 EXPORT_SYMBOL(kernel_bind);
3179 
3180 int kernel_listen(struct socket *sock, int backlog)
3181 {
3182 	return sock->ops->listen(sock, backlog);
3183 }
3184 EXPORT_SYMBOL(kernel_listen);
3185 
3186 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
3187 {
3188 	struct sock *sk = sock->sk;
3189 	int err;
3190 
3191 	err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
3192 			       newsock);
3193 	if (err < 0)
3194 		goto done;
3195 
3196 	err = sock->ops->accept(sock, *newsock, flags);
3197 	if (err < 0) {
3198 		sock_release(*newsock);
3199 		*newsock = NULL;
3200 		goto done;
3201 	}
3202 
3203 	(*newsock)->ops = sock->ops;
3204 	__module_get((*newsock)->ops->owner);
3205 
3206 done:
3207 	return err;
3208 }
3209 EXPORT_SYMBOL(kernel_accept);
3210 
3211 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
3212 		   int flags)
3213 {
3214 	return sock->ops->connect(sock, addr, addrlen, flags);
3215 }
3216 EXPORT_SYMBOL(kernel_connect);
3217 
3218 int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
3219 			 int *addrlen)
3220 {
3221 	return sock->ops->getname(sock, addr, addrlen, 0);
3222 }
3223 EXPORT_SYMBOL(kernel_getsockname);
3224 
3225 int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
3226 			 int *addrlen)
3227 {
3228 	return sock->ops->getname(sock, addr, addrlen, 1);
3229 }
3230 EXPORT_SYMBOL(kernel_getpeername);
3231 
3232 int kernel_getsockopt(struct socket *sock, int level, int optname,
3233 			char *optval, int *optlen)
3234 {
3235 	mm_segment_t oldfs = get_fs();
3236 	char __user *uoptval;
3237 	int __user *uoptlen;
3238 	int err;
3239 
3240 	uoptval = (char __user __force *) optval;
3241 	uoptlen = (int __user __force *) optlen;
3242 
3243 	set_fs(KERNEL_DS);
3244 	if (level == SOL_SOCKET)
3245 		err = sock_getsockopt(sock, level, optname, uoptval, uoptlen);
3246 	else
3247 		err = sock->ops->getsockopt(sock, level, optname, uoptval,
3248 					    uoptlen);
3249 	set_fs(oldfs);
3250 	return err;
3251 }
3252 EXPORT_SYMBOL(kernel_getsockopt);
3253 
3254 int kernel_setsockopt(struct socket *sock, int level, int optname,
3255 			char *optval, unsigned int optlen)
3256 {
3257 	mm_segment_t oldfs = get_fs();
3258 	char __user *uoptval;
3259 	int err;
3260 
3261 	uoptval = (char __user __force *) optval;
3262 
3263 	set_fs(KERNEL_DS);
3264 	if (level == SOL_SOCKET)
3265 		err = sock_setsockopt(sock, level, optname, uoptval, optlen);
3266 	else
3267 		err = sock->ops->setsockopt(sock, level, optname, uoptval,
3268 					    optlen);
3269 	set_fs(oldfs);
3270 	return err;
3271 }
3272 EXPORT_SYMBOL(kernel_setsockopt);
3273 
3274 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
3275 		    size_t size, int flags)
3276 {
3277 	if (sock->ops->sendpage)
3278 		return sock->ops->sendpage(sock, page, offset, size, flags);
3279 
3280 	return sock_no_sendpage(sock, page, offset, size, flags);
3281 }
3282 EXPORT_SYMBOL(kernel_sendpage);
3283 
3284 int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg)
3285 {
3286 	mm_segment_t oldfs = get_fs();
3287 	int err;
3288 
3289 	set_fs(KERNEL_DS);
3290 	err = sock->ops->ioctl(sock, cmd, arg);
3291 	set_fs(oldfs);
3292 
3293 	return err;
3294 }
3295 EXPORT_SYMBOL(kernel_sock_ioctl);
3296 
3297 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
3298 {
3299 	return sock->ops->shutdown(sock, how);
3300 }
3301 EXPORT_SYMBOL(kernel_sock_shutdown);
3302