xref: /linux/net/socket.c (revision 5bbfea1eacdf584d0d159e38c01ee190162706d9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * NET		An implementation of the SOCKET network access protocol.
4  *
5  * Version:	@(#)socket.c	1.1.93	18/02/95
6  *
7  * Authors:	Orest Zborowski, <obz@Kodak.COM>
8  *		Ross Biro
9  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10  *
11  * Fixes:
12  *		Anonymous	:	NOTSOCK/BADF cleanup. Error fix in
13  *					shutdown()
14  *		Alan Cox	:	verify_area() fixes
15  *		Alan Cox	:	Removed DDI
16  *		Jonathan Kamens	:	SOCK_DGRAM reconnect bug
17  *		Alan Cox	:	Moved a load of checks to the very
18  *					top level.
19  *		Alan Cox	:	Move address structures to/from user
20  *					mode above the protocol layers.
21  *		Rob Janssen	:	Allow 0 length sends.
22  *		Alan Cox	:	Asynchronous I/O support (cribbed from the
23  *					tty drivers).
24  *		Niibe Yutaka	:	Asynchronous I/O for writes (4.4BSD style)
25  *		Jeff Uphoff	:	Made max number of sockets command-line
26  *					configurable.
27  *		Matti Aarnio	:	Made the number of sockets dynamic,
28  *					to be allocated when needed, and mr.
29  *					Uphoff's max is used as max to be
30  *					allowed to allocate.
31  *		Linus		:	Argh. removed all the socket allocation
32  *					altogether: it's in the inode now.
33  *		Alan Cox	:	Made sock_alloc()/sock_release() public
34  *					for NetROM and future kernel nfsd type
35  *					stuff.
36  *		Alan Cox	:	sendmsg/recvmsg basics.
37  *		Tom Dyas	:	Export net symbols.
38  *		Marcin Dalecki	:	Fixed problems with CONFIG_NET="n".
39  *		Alan Cox	:	Added thread locking to sys_* calls
40  *					for sockets. May have errors at the
41  *					moment.
42  *		Kevin Buhr	:	Fixed the dumb errors in the above.
43  *		Andi Kleen	:	Some small cleanups, optimizations,
44  *					and fixed a copy_from_user() bug.
45  *		Tigran Aivazian	:	sys_send(args) calls sys_sendto(args, NULL, 0)
46  *		Tigran Aivazian	:	Made listen(2) backlog sanity checks
47  *					protocol-independent
48  *
49  *	This module is effectively the top level interface to the BSD socket
50  *	paradigm.
51  *
52  *	Based upon Swansea University Computer Society NET3.039
53  */
54 
55 #include <linux/ethtool.h>
56 #include <linux/mm.h>
57 #include <linux/socket.h>
58 #include <linux/file.h>
59 #include <linux/net.h>
60 #include <linux/interrupt.h>
61 #include <linux/thread_info.h>
62 #include <linux/rcupdate.h>
63 #include <linux/netdevice.h>
64 #include <linux/proc_fs.h>
65 #include <linux/seq_file.h>
66 #include <linux/mutex.h>
67 #include <linux/if_bridge.h>
68 #include <linux/if_vlan.h>
69 #include <linux/ptp_classify.h>
70 #include <linux/init.h>
71 #include <linux/poll.h>
72 #include <linux/cache.h>
73 #include <linux/module.h>
74 #include <linux/highmem.h>
75 #include <linux/mount.h>
76 #include <linux/pseudo_fs.h>
77 #include <linux/security.h>
78 #include <linux/syscalls.h>
79 #include <linux/compat.h>
80 #include <linux/kmod.h>
81 #include <linux/audit.h>
82 #include <linux/wireless.h>
83 #include <linux/nsproxy.h>
84 #include <linux/magic.h>
85 #include <linux/slab.h>
86 #include <linux/xattr.h>
87 #include <linux/nospec.h>
88 #include <linux/indirect_call_wrapper.h>
89 
90 #include <linux/uaccess.h>
91 #include <asm/unistd.h>
92 
93 #include <net/compat.h>
94 #include <net/wext.h>
95 #include <net/cls_cgroup.h>
96 
97 #include <net/sock.h>
98 #include <linux/netfilter.h>
99 
100 #include <linux/if_tun.h>
101 #include <linux/ipv6_route.h>
102 #include <linux/route.h>
103 #include <linux/termios.h>
104 #include <linux/sockios.h>
105 #include <net/busy_poll.h>
106 #include <linux/errqueue.h>
107 #include <linux/ptp_clock_kernel.h>
108 
109 #ifdef CONFIG_NET_RX_BUSY_POLL
110 unsigned int sysctl_net_busy_read __read_mostly;
111 unsigned int sysctl_net_busy_poll __read_mostly;
112 #endif
113 
114 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to);
115 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
116 static int sock_mmap(struct file *file, struct vm_area_struct *vma);
117 
118 static int sock_close(struct inode *inode, struct file *file);
119 static __poll_t sock_poll(struct file *file,
120 			      struct poll_table_struct *wait);
121 static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
122 #ifdef CONFIG_COMPAT
123 static long compat_sock_ioctl(struct file *file,
124 			      unsigned int cmd, unsigned long arg);
125 #endif
126 static int sock_fasync(int fd, struct file *filp, int on);
127 static ssize_t sock_sendpage(struct file *file, struct page *page,
128 			     int offset, size_t size, loff_t *ppos, int more);
129 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
130 				struct pipe_inode_info *pipe, size_t len,
131 				unsigned int flags);
132 
133 #ifdef CONFIG_PROC_FS
134 static void sock_show_fdinfo(struct seq_file *m, struct file *f)
135 {
136 	struct socket *sock = f->private_data;
137 
138 	if (sock->ops->show_fdinfo)
139 		sock->ops->show_fdinfo(m, sock);
140 }
141 #else
142 #define sock_show_fdinfo NULL
143 #endif
144 
145 /*
146  *	Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
147  *	in the operation structures but are done directly via the socketcall() multiplexor.
148  */
149 
150 static const struct file_operations socket_file_ops = {
151 	.owner =	THIS_MODULE,
152 	.llseek =	no_llseek,
153 	.read_iter =	sock_read_iter,
154 	.write_iter =	sock_write_iter,
155 	.poll =		sock_poll,
156 	.unlocked_ioctl = sock_ioctl,
157 #ifdef CONFIG_COMPAT
158 	.compat_ioctl = compat_sock_ioctl,
159 #endif
160 	.mmap =		sock_mmap,
161 	.release =	sock_close,
162 	.fasync =	sock_fasync,
163 	.sendpage =	sock_sendpage,
164 	.splice_write = generic_splice_sendpage,
165 	.splice_read =	sock_splice_read,
166 	.show_fdinfo =	sock_show_fdinfo,
167 };
168 
169 static const char * const pf_family_names[] = {
170 	[PF_UNSPEC]	= "PF_UNSPEC",
171 	[PF_UNIX]	= "PF_UNIX/PF_LOCAL",
172 	[PF_INET]	= "PF_INET",
173 	[PF_AX25]	= "PF_AX25",
174 	[PF_IPX]	= "PF_IPX",
175 	[PF_APPLETALK]	= "PF_APPLETALK",
176 	[PF_NETROM]	= "PF_NETROM",
177 	[PF_BRIDGE]	= "PF_BRIDGE",
178 	[PF_ATMPVC]	= "PF_ATMPVC",
179 	[PF_X25]	= "PF_X25",
180 	[PF_INET6]	= "PF_INET6",
181 	[PF_ROSE]	= "PF_ROSE",
182 	[PF_DECnet]	= "PF_DECnet",
183 	[PF_NETBEUI]	= "PF_NETBEUI",
184 	[PF_SECURITY]	= "PF_SECURITY",
185 	[PF_KEY]	= "PF_KEY",
186 	[PF_NETLINK]	= "PF_NETLINK/PF_ROUTE",
187 	[PF_PACKET]	= "PF_PACKET",
188 	[PF_ASH]	= "PF_ASH",
189 	[PF_ECONET]	= "PF_ECONET",
190 	[PF_ATMSVC]	= "PF_ATMSVC",
191 	[PF_RDS]	= "PF_RDS",
192 	[PF_SNA]	= "PF_SNA",
193 	[PF_IRDA]	= "PF_IRDA",
194 	[PF_PPPOX]	= "PF_PPPOX",
195 	[PF_WANPIPE]	= "PF_WANPIPE",
196 	[PF_LLC]	= "PF_LLC",
197 	[PF_IB]		= "PF_IB",
198 	[PF_MPLS]	= "PF_MPLS",
199 	[PF_CAN]	= "PF_CAN",
200 	[PF_TIPC]	= "PF_TIPC",
201 	[PF_BLUETOOTH]	= "PF_BLUETOOTH",
202 	[PF_IUCV]	= "PF_IUCV",
203 	[PF_RXRPC]	= "PF_RXRPC",
204 	[PF_ISDN]	= "PF_ISDN",
205 	[PF_PHONET]	= "PF_PHONET",
206 	[PF_IEEE802154]	= "PF_IEEE802154",
207 	[PF_CAIF]	= "PF_CAIF",
208 	[PF_ALG]	= "PF_ALG",
209 	[PF_NFC]	= "PF_NFC",
210 	[PF_VSOCK]	= "PF_VSOCK",
211 	[PF_KCM]	= "PF_KCM",
212 	[PF_QIPCRTR]	= "PF_QIPCRTR",
213 	[PF_SMC]	= "PF_SMC",
214 	[PF_XDP]	= "PF_XDP",
215 	[PF_MCTP]	= "PF_MCTP",
216 };
217 
218 /*
219  *	The protocol list. Each protocol is registered in here.
220  */
221 
222 static DEFINE_SPINLOCK(net_family_lock);
223 static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
224 
225 /*
226  * Support routines.
227  * Move socket addresses back and forth across the kernel/user
228  * divide and look after the messy bits.
229  */
230 
231 /**
232  *	move_addr_to_kernel	-	copy a socket address into kernel space
233  *	@uaddr: Address in user space
234  *	@kaddr: Address in kernel space
235  *	@ulen: Length in user space
236  *
237  *	The address is copied into kernel space. If the provided address is
238  *	too long an error code of -EINVAL is returned. If the copy gives
239  *	invalid addresses -EFAULT is returned. On a success 0 is returned.
240  */
241 
242 int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
243 {
244 	if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
245 		return -EINVAL;
246 	if (ulen == 0)
247 		return 0;
248 	if (copy_from_user(kaddr, uaddr, ulen))
249 		return -EFAULT;
250 	return audit_sockaddr(ulen, kaddr);
251 }
252 
253 /**
254  *	move_addr_to_user	-	copy an address to user space
255  *	@kaddr: kernel space address
256  *	@klen: length of address in kernel
257  *	@uaddr: user space address
258  *	@ulen: pointer to user length field
259  *
260  *	The value pointed to by ulen on entry is the buffer length available.
261  *	This is overwritten with the buffer space used. -EINVAL is returned
262  *	if an overlong buffer is specified or a negative buffer size. -EFAULT
263  *	is returned if either the buffer or the length field are not
264  *	accessible.
265  *	After copying the data up to the limit the user specifies, the true
266  *	length of the data is written over the length limit the user
267  *	specified. Zero is returned for a success.
268  */
269 
270 static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
271 			     void __user *uaddr, int __user *ulen)
272 {
273 	int err;
274 	int len;
275 
276 	BUG_ON(klen > sizeof(struct sockaddr_storage));
277 	err = get_user(len, ulen);
278 	if (err)
279 		return err;
280 	if (len > klen)
281 		len = klen;
282 	if (len < 0)
283 		return -EINVAL;
284 	if (len) {
285 		if (audit_sockaddr(klen, kaddr))
286 			return -ENOMEM;
287 		if (copy_to_user(uaddr, kaddr, len))
288 			return -EFAULT;
289 	}
290 	/*
291 	 *      "fromlen shall refer to the value before truncation.."
292 	 *                      1003.1g
293 	 */
294 	return __put_user(klen, ulen);
295 }
296 
297 static struct kmem_cache *sock_inode_cachep __ro_after_init;
298 
299 static struct inode *sock_alloc_inode(struct super_block *sb)
300 {
301 	struct socket_alloc *ei;
302 
303 	ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
304 	if (!ei)
305 		return NULL;
306 	init_waitqueue_head(&ei->socket.wq.wait);
307 	ei->socket.wq.fasync_list = NULL;
308 	ei->socket.wq.flags = 0;
309 
310 	ei->socket.state = SS_UNCONNECTED;
311 	ei->socket.flags = 0;
312 	ei->socket.ops = NULL;
313 	ei->socket.sk = NULL;
314 	ei->socket.file = NULL;
315 
316 	return &ei->vfs_inode;
317 }
318 
319 static void sock_free_inode(struct inode *inode)
320 {
321 	struct socket_alloc *ei;
322 
323 	ei = container_of(inode, struct socket_alloc, vfs_inode);
324 	kmem_cache_free(sock_inode_cachep, ei);
325 }
326 
327 static void init_once(void *foo)
328 {
329 	struct socket_alloc *ei = (struct socket_alloc *)foo;
330 
331 	inode_init_once(&ei->vfs_inode);
332 }
333 
334 static void init_inodecache(void)
335 {
336 	sock_inode_cachep = kmem_cache_create("sock_inode_cache",
337 					      sizeof(struct socket_alloc),
338 					      0,
339 					      (SLAB_HWCACHE_ALIGN |
340 					       SLAB_RECLAIM_ACCOUNT |
341 					       SLAB_MEM_SPREAD | SLAB_ACCOUNT),
342 					      init_once);
343 	BUG_ON(sock_inode_cachep == NULL);
344 }
345 
346 static const struct super_operations sockfs_ops = {
347 	.alloc_inode	= sock_alloc_inode,
348 	.free_inode	= sock_free_inode,
349 	.statfs		= simple_statfs,
350 };
351 
352 /*
353  * sockfs_dname() is called from d_path().
354  */
355 static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
356 {
357 	return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",
358 				d_inode(dentry)->i_ino);
359 }
360 
361 static const struct dentry_operations sockfs_dentry_operations = {
362 	.d_dname  = sockfs_dname,
363 };
364 
365 static int sockfs_xattr_get(const struct xattr_handler *handler,
366 			    struct dentry *dentry, struct inode *inode,
367 			    const char *suffix, void *value, size_t size)
368 {
369 	if (value) {
370 		if (dentry->d_name.len + 1 > size)
371 			return -ERANGE;
372 		memcpy(value, dentry->d_name.name, dentry->d_name.len + 1);
373 	}
374 	return dentry->d_name.len + 1;
375 }
376 
377 #define XATTR_SOCKPROTONAME_SUFFIX "sockprotoname"
378 #define XATTR_NAME_SOCKPROTONAME (XATTR_SYSTEM_PREFIX XATTR_SOCKPROTONAME_SUFFIX)
379 #define XATTR_NAME_SOCKPROTONAME_LEN (sizeof(XATTR_NAME_SOCKPROTONAME)-1)
380 
381 static const struct xattr_handler sockfs_xattr_handler = {
382 	.name = XATTR_NAME_SOCKPROTONAME,
383 	.get = sockfs_xattr_get,
384 };
385 
386 static int sockfs_security_xattr_set(const struct xattr_handler *handler,
387 				     struct user_namespace *mnt_userns,
388 				     struct dentry *dentry, struct inode *inode,
389 				     const char *suffix, const void *value,
390 				     size_t size, int flags)
391 {
392 	/* Handled by LSM. */
393 	return -EAGAIN;
394 }
395 
396 static const struct xattr_handler sockfs_security_xattr_handler = {
397 	.prefix = XATTR_SECURITY_PREFIX,
398 	.set = sockfs_security_xattr_set,
399 };
400 
401 static const struct xattr_handler *sockfs_xattr_handlers[] = {
402 	&sockfs_xattr_handler,
403 	&sockfs_security_xattr_handler,
404 	NULL
405 };
406 
407 static int sockfs_init_fs_context(struct fs_context *fc)
408 {
409 	struct pseudo_fs_context *ctx = init_pseudo(fc, SOCKFS_MAGIC);
410 	if (!ctx)
411 		return -ENOMEM;
412 	ctx->ops = &sockfs_ops;
413 	ctx->dops = &sockfs_dentry_operations;
414 	ctx->xattr = sockfs_xattr_handlers;
415 	return 0;
416 }
417 
418 static struct vfsmount *sock_mnt __read_mostly;
419 
420 static struct file_system_type sock_fs_type = {
421 	.name =		"sockfs",
422 	.init_fs_context = sockfs_init_fs_context,
423 	.kill_sb =	kill_anon_super,
424 };
425 
426 /*
427  *	Obtains the first available file descriptor and sets it up for use.
428  *
429  *	These functions create file structures and maps them to fd space
430  *	of the current process. On success it returns file descriptor
431  *	and file struct implicitly stored in sock->file.
432  *	Note that another thread may close file descriptor before we return
433  *	from this function. We use the fact that now we do not refer
434  *	to socket after mapping. If one day we will need it, this
435  *	function will increment ref. count on file by 1.
436  *
437  *	In any case returned fd MAY BE not valid!
438  *	This race condition is unavoidable
439  *	with shared fd spaces, we cannot solve it inside kernel,
440  *	but we take care of internal coherence yet.
441  */
442 
443 /**
444  *	sock_alloc_file - Bind a &socket to a &file
445  *	@sock: socket
446  *	@flags: file status flags
447  *	@dname: protocol name
448  *
449  *	Returns the &file bound with @sock, implicitly storing it
450  *	in sock->file. If dname is %NULL, sets to "".
451  *	On failure the return is a ERR pointer (see linux/err.h).
452  *	This function uses GFP_KERNEL internally.
453  */
454 
455 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
456 {
457 	struct file *file;
458 
459 	if (!dname)
460 		dname = sock->sk ? sock->sk->sk_prot_creator->name : "";
461 
462 	file = alloc_file_pseudo(SOCK_INODE(sock), sock_mnt, dname,
463 				O_RDWR | (flags & O_NONBLOCK),
464 				&socket_file_ops);
465 	if (IS_ERR(file)) {
466 		sock_release(sock);
467 		return file;
468 	}
469 
470 	sock->file = file;
471 	file->private_data = sock;
472 	stream_open(SOCK_INODE(sock), file);
473 	return file;
474 }
475 EXPORT_SYMBOL(sock_alloc_file);
476 
477 static int sock_map_fd(struct socket *sock, int flags)
478 {
479 	struct file *newfile;
480 	int fd = get_unused_fd_flags(flags);
481 	if (unlikely(fd < 0)) {
482 		sock_release(sock);
483 		return fd;
484 	}
485 
486 	newfile = sock_alloc_file(sock, flags, NULL);
487 	if (!IS_ERR(newfile)) {
488 		fd_install(fd, newfile);
489 		return fd;
490 	}
491 
492 	put_unused_fd(fd);
493 	return PTR_ERR(newfile);
494 }
495 
496 /**
497  *	sock_from_file - Return the &socket bounded to @file.
498  *	@file: file
499  *
500  *	On failure returns %NULL.
501  */
502 
503 struct socket *sock_from_file(struct file *file)
504 {
505 	if (file->f_op == &socket_file_ops)
506 		return file->private_data;	/* set in sock_map_fd */
507 
508 	return NULL;
509 }
510 EXPORT_SYMBOL(sock_from_file);
511 
512 /**
513  *	sockfd_lookup - Go from a file number to its socket slot
514  *	@fd: file handle
515  *	@err: pointer to an error code return
516  *
517  *	The file handle passed in is locked and the socket it is bound
518  *	to is returned. If an error occurs the err pointer is overwritten
519  *	with a negative errno code and NULL is returned. The function checks
520  *	for both invalid handles and passing a handle which is not a socket.
521  *
522  *	On a success the socket object pointer is returned.
523  */
524 
525 struct socket *sockfd_lookup(int fd, int *err)
526 {
527 	struct file *file;
528 	struct socket *sock;
529 
530 	file = fget(fd);
531 	if (!file) {
532 		*err = -EBADF;
533 		return NULL;
534 	}
535 
536 	sock = sock_from_file(file);
537 	if (!sock) {
538 		*err = -ENOTSOCK;
539 		fput(file);
540 	}
541 	return sock;
542 }
543 EXPORT_SYMBOL(sockfd_lookup);
544 
545 static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
546 {
547 	struct fd f = fdget(fd);
548 	struct socket *sock;
549 
550 	*err = -EBADF;
551 	if (f.file) {
552 		sock = sock_from_file(f.file);
553 		if (likely(sock)) {
554 			*fput_needed = f.flags & FDPUT_FPUT;
555 			return sock;
556 		}
557 		*err = -ENOTSOCK;
558 		fdput(f);
559 	}
560 	return NULL;
561 }
562 
563 static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
564 				size_t size)
565 {
566 	ssize_t len;
567 	ssize_t used = 0;
568 
569 	len = security_inode_listsecurity(d_inode(dentry), buffer, size);
570 	if (len < 0)
571 		return len;
572 	used += len;
573 	if (buffer) {
574 		if (size < used)
575 			return -ERANGE;
576 		buffer += len;
577 	}
578 
579 	len = (XATTR_NAME_SOCKPROTONAME_LEN + 1);
580 	used += len;
581 	if (buffer) {
582 		if (size < used)
583 			return -ERANGE;
584 		memcpy(buffer, XATTR_NAME_SOCKPROTONAME, len);
585 		buffer += len;
586 	}
587 
588 	return used;
589 }
590 
591 static int sockfs_setattr(struct user_namespace *mnt_userns,
592 			  struct dentry *dentry, struct iattr *iattr)
593 {
594 	int err = simple_setattr(&init_user_ns, dentry, iattr);
595 
596 	if (!err && (iattr->ia_valid & ATTR_UID)) {
597 		struct socket *sock = SOCKET_I(d_inode(dentry));
598 
599 		if (sock->sk)
600 			sock->sk->sk_uid = iattr->ia_uid;
601 		else
602 			err = -ENOENT;
603 	}
604 
605 	return err;
606 }
607 
608 static const struct inode_operations sockfs_inode_ops = {
609 	.listxattr = sockfs_listxattr,
610 	.setattr = sockfs_setattr,
611 };
612 
613 /**
614  *	sock_alloc - allocate a socket
615  *
616  *	Allocate a new inode and socket object. The two are bound together
617  *	and initialised. The socket is then returned. If we are out of inodes
618  *	NULL is returned. This functions uses GFP_KERNEL internally.
619  */
620 
621 struct socket *sock_alloc(void)
622 {
623 	struct inode *inode;
624 	struct socket *sock;
625 
626 	inode = new_inode_pseudo(sock_mnt->mnt_sb);
627 	if (!inode)
628 		return NULL;
629 
630 	sock = SOCKET_I(inode);
631 
632 	inode->i_ino = get_next_ino();
633 	inode->i_mode = S_IFSOCK | S_IRWXUGO;
634 	inode->i_uid = current_fsuid();
635 	inode->i_gid = current_fsgid();
636 	inode->i_op = &sockfs_inode_ops;
637 
638 	return sock;
639 }
640 EXPORT_SYMBOL(sock_alloc);
641 
642 static void __sock_release(struct socket *sock, struct inode *inode)
643 {
644 	if (sock->ops) {
645 		struct module *owner = sock->ops->owner;
646 
647 		if (inode)
648 			inode_lock(inode);
649 		sock->ops->release(sock);
650 		sock->sk = NULL;
651 		if (inode)
652 			inode_unlock(inode);
653 		sock->ops = NULL;
654 		module_put(owner);
655 	}
656 
657 	if (sock->wq.fasync_list)
658 		pr_err("%s: fasync list not empty!\n", __func__);
659 
660 	if (!sock->file) {
661 		iput(SOCK_INODE(sock));
662 		return;
663 	}
664 	sock->file = NULL;
665 }
666 
667 /**
668  *	sock_release - close a socket
669  *	@sock: socket to close
670  *
671  *	The socket is released from the protocol stack if it has a release
672  *	callback, and the inode is then released if the socket is bound to
673  *	an inode not a file.
674  */
675 void sock_release(struct socket *sock)
676 {
677 	__sock_release(sock, NULL);
678 }
679 EXPORT_SYMBOL(sock_release);
680 
681 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
682 {
683 	u8 flags = *tx_flags;
684 
685 	if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE)
686 		flags |= SKBTX_HW_TSTAMP;
687 
688 	if (tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)
689 		flags |= SKBTX_SW_TSTAMP;
690 
691 	if (tsflags & SOF_TIMESTAMPING_TX_SCHED)
692 		flags |= SKBTX_SCHED_TSTAMP;
693 
694 	*tx_flags = flags;
695 }
696 EXPORT_SYMBOL(__sock_tx_timestamp);
697 
698 INDIRECT_CALLABLE_DECLARE(int inet_sendmsg(struct socket *, struct msghdr *,
699 					   size_t));
700 INDIRECT_CALLABLE_DECLARE(int inet6_sendmsg(struct socket *, struct msghdr *,
701 					    size_t));
702 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
703 {
704 	int ret = INDIRECT_CALL_INET(sock->ops->sendmsg, inet6_sendmsg,
705 				     inet_sendmsg, sock, msg,
706 				     msg_data_left(msg));
707 	BUG_ON(ret == -EIOCBQUEUED);
708 	return ret;
709 }
710 
711 /**
712  *	sock_sendmsg - send a message through @sock
713  *	@sock: socket
714  *	@msg: message to send
715  *
716  *	Sends @msg through @sock, passing through LSM.
717  *	Returns the number of bytes sent, or an error code.
718  */
719 int sock_sendmsg(struct socket *sock, struct msghdr *msg)
720 {
721 	int err = security_socket_sendmsg(sock, msg,
722 					  msg_data_left(msg));
723 
724 	return err ?: sock_sendmsg_nosec(sock, msg);
725 }
726 EXPORT_SYMBOL(sock_sendmsg);
727 
728 /**
729  *	kernel_sendmsg - send a message through @sock (kernel-space)
730  *	@sock: socket
731  *	@msg: message header
732  *	@vec: kernel vec
733  *	@num: vec array length
734  *	@size: total message data size
735  *
736  *	Builds the message data with @vec and sends it through @sock.
737  *	Returns the number of bytes sent, or an error code.
738  */
739 
740 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
741 		   struct kvec *vec, size_t num, size_t size)
742 {
743 	iov_iter_kvec(&msg->msg_iter, WRITE, vec, num, size);
744 	return sock_sendmsg(sock, msg);
745 }
746 EXPORT_SYMBOL(kernel_sendmsg);
747 
748 /**
749  *	kernel_sendmsg_locked - send a message through @sock (kernel-space)
750  *	@sk: sock
751  *	@msg: message header
752  *	@vec: output s/g array
753  *	@num: output s/g array length
754  *	@size: total message data size
755  *
756  *	Builds the message data with @vec and sends it through @sock.
757  *	Returns the number of bytes sent, or an error code.
758  *	Caller must hold @sk.
759  */
760 
761 int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
762 			  struct kvec *vec, size_t num, size_t size)
763 {
764 	struct socket *sock = sk->sk_socket;
765 
766 	if (!sock->ops->sendmsg_locked)
767 		return sock_no_sendmsg_locked(sk, msg, size);
768 
769 	iov_iter_kvec(&msg->msg_iter, WRITE, vec, num, size);
770 
771 	return sock->ops->sendmsg_locked(sk, msg, msg_data_left(msg));
772 }
773 EXPORT_SYMBOL(kernel_sendmsg_locked);
774 
775 static bool skb_is_err_queue(const struct sk_buff *skb)
776 {
777 	/* pkt_type of skbs enqueued on the error queue are set to
778 	 * PACKET_OUTGOING in skb_set_err_queue(). This is only safe to do
779 	 * in recvmsg, since skbs received on a local socket will never
780 	 * have a pkt_type of PACKET_OUTGOING.
781 	 */
782 	return skb->pkt_type == PACKET_OUTGOING;
783 }
784 
785 /* On transmit, software and hardware timestamps are returned independently.
786  * As the two skb clones share the hardware timestamp, which may be updated
787  * before the software timestamp is received, a hardware TX timestamp may be
788  * returned only if there is no software TX timestamp. Ignore false software
789  * timestamps, which may be made in the __sock_recv_timestamp() call when the
790  * option SO_TIMESTAMP_OLD(NS) is enabled on the socket, even when the skb has a
791  * hardware timestamp.
792  */
793 static bool skb_is_swtx_tstamp(const struct sk_buff *skb, int false_tstamp)
794 {
795 	return skb->tstamp && !false_tstamp && skb_is_err_queue(skb);
796 }
797 
798 static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb)
799 {
800 	struct scm_ts_pktinfo ts_pktinfo;
801 	struct net_device *orig_dev;
802 
803 	if (!skb_mac_header_was_set(skb))
804 		return;
805 
806 	memset(&ts_pktinfo, 0, sizeof(ts_pktinfo));
807 
808 	rcu_read_lock();
809 	orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
810 	if (orig_dev)
811 		ts_pktinfo.if_index = orig_dev->ifindex;
812 	rcu_read_unlock();
813 
814 	ts_pktinfo.pkt_length = skb->len - skb_mac_offset(skb);
815 	put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
816 		 sizeof(ts_pktinfo), &ts_pktinfo);
817 }
818 
819 /*
820  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
821  */
822 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
823 	struct sk_buff *skb)
824 {
825 	int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
826 	int new_tstamp = sock_flag(sk, SOCK_TSTAMP_NEW);
827 	struct scm_timestamping_internal tss;
828 
829 	int empty = 1, false_tstamp = 0;
830 	struct skb_shared_hwtstamps *shhwtstamps =
831 		skb_hwtstamps(skb);
832 
833 	/* Race occurred between timestamp enabling and packet
834 	   receiving.  Fill in the current time for now. */
835 	if (need_software_tstamp && skb->tstamp == 0) {
836 		__net_timestamp(skb);
837 		false_tstamp = 1;
838 	}
839 
840 	if (need_software_tstamp) {
841 		if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
842 			if (new_tstamp) {
843 				struct __kernel_sock_timeval tv;
844 
845 				skb_get_new_timestamp(skb, &tv);
846 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_NEW,
847 					 sizeof(tv), &tv);
848 			} else {
849 				struct __kernel_old_timeval tv;
850 
851 				skb_get_timestamp(skb, &tv);
852 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD,
853 					 sizeof(tv), &tv);
854 			}
855 		} else {
856 			if (new_tstamp) {
857 				struct __kernel_timespec ts;
858 
859 				skb_get_new_timestampns(skb, &ts);
860 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_NEW,
861 					 sizeof(ts), &ts);
862 			} else {
863 				struct __kernel_old_timespec ts;
864 
865 				skb_get_timestampns(skb, &ts);
866 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_OLD,
867 					 sizeof(ts), &ts);
868 			}
869 		}
870 	}
871 
872 	memset(&tss, 0, sizeof(tss));
873 	if ((sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
874 	    ktime_to_timespec64_cond(skb->tstamp, tss.ts + 0))
875 		empty = 0;
876 	if (shhwtstamps &&
877 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
878 	    !skb_is_swtx_tstamp(skb, false_tstamp)) {
879 		if (sk->sk_tsflags & SOF_TIMESTAMPING_BIND_PHC)
880 			ptp_convert_timestamp(shhwtstamps, sk->sk_bind_phc);
881 
882 		if (ktime_to_timespec64_cond(shhwtstamps->hwtstamp,
883 					     tss.ts + 2)) {
884 			empty = 0;
885 
886 			if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
887 			    !skb_is_err_queue(skb))
888 				put_ts_pktinfo(msg, skb);
889 		}
890 	}
891 	if (!empty) {
892 		if (sock_flag(sk, SOCK_TSTAMP_NEW))
893 			put_cmsg_scm_timestamping64(msg, &tss);
894 		else
895 			put_cmsg_scm_timestamping(msg, &tss);
896 
897 		if (skb_is_err_queue(skb) && skb->len &&
898 		    SKB_EXT_ERR(skb)->opt_stats)
899 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS,
900 				 skb->len, skb->data);
901 	}
902 }
903 EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
904 
905 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
906 	struct sk_buff *skb)
907 {
908 	int ack;
909 
910 	if (!sock_flag(sk, SOCK_WIFI_STATUS))
911 		return;
912 	if (!skb->wifi_acked_valid)
913 		return;
914 
915 	ack = skb->wifi_acked;
916 
917 	put_cmsg(msg, SOL_SOCKET, SCM_WIFI_STATUS, sizeof(ack), &ack);
918 }
919 EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
920 
921 static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
922 				   struct sk_buff *skb)
923 {
924 	if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
925 		put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
926 			sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
927 }
928 
929 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
930 	struct sk_buff *skb)
931 {
932 	sock_recv_timestamp(msg, sk, skb);
933 	sock_recv_drops(msg, sk, skb);
934 }
935 EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops);
936 
937 INDIRECT_CALLABLE_DECLARE(int inet_recvmsg(struct socket *, struct msghdr *,
938 					   size_t, int));
939 INDIRECT_CALLABLE_DECLARE(int inet6_recvmsg(struct socket *, struct msghdr *,
940 					    size_t, int));
941 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
942 				     int flags)
943 {
944 	return INDIRECT_CALL_INET(sock->ops->recvmsg, inet6_recvmsg,
945 				  inet_recvmsg, sock, msg, msg_data_left(msg),
946 				  flags);
947 }
948 
949 /**
950  *	sock_recvmsg - receive a message from @sock
951  *	@sock: socket
952  *	@msg: message to receive
953  *	@flags: message flags
954  *
955  *	Receives @msg from @sock, passing through LSM. Returns the total number
956  *	of bytes received, or an error.
957  */
958 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
959 {
960 	int err = security_socket_recvmsg(sock, msg, msg_data_left(msg), flags);
961 
962 	return err ?: sock_recvmsg_nosec(sock, msg, flags);
963 }
964 EXPORT_SYMBOL(sock_recvmsg);
965 
966 /**
967  *	kernel_recvmsg - Receive a message from a socket (kernel space)
968  *	@sock: The socket to receive the message from
969  *	@msg: Received message
970  *	@vec: Input s/g array for message data
971  *	@num: Size of input s/g array
972  *	@size: Number of bytes to read
973  *	@flags: Message flags (MSG_DONTWAIT, etc...)
974  *
975  *	On return the msg structure contains the scatter/gather array passed in the
976  *	vec argument. The array is modified so that it consists of the unfilled
977  *	portion of the original array.
978  *
979  *	The returned value is the total number of bytes received, or an error.
980  */
981 
982 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
983 		   struct kvec *vec, size_t num, size_t size, int flags)
984 {
985 	msg->msg_control_is_user = false;
986 	iov_iter_kvec(&msg->msg_iter, READ, vec, num, size);
987 	return sock_recvmsg(sock, msg, flags);
988 }
989 EXPORT_SYMBOL(kernel_recvmsg);
990 
991 static ssize_t sock_sendpage(struct file *file, struct page *page,
992 			     int offset, size_t size, loff_t *ppos, int more)
993 {
994 	struct socket *sock;
995 	int flags;
996 
997 	sock = file->private_data;
998 
999 	flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
1000 	/* more is a combination of MSG_MORE and MSG_SENDPAGE_NOTLAST */
1001 	flags |= more;
1002 
1003 	return kernel_sendpage(sock, page, offset, size, flags);
1004 }
1005 
1006 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
1007 				struct pipe_inode_info *pipe, size_t len,
1008 				unsigned int flags)
1009 {
1010 	struct socket *sock = file->private_data;
1011 
1012 	if (unlikely(!sock->ops->splice_read))
1013 		return generic_file_splice_read(file, ppos, pipe, len, flags);
1014 
1015 	return sock->ops->splice_read(sock, ppos, pipe, len, flags);
1016 }
1017 
1018 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
1019 {
1020 	struct file *file = iocb->ki_filp;
1021 	struct socket *sock = file->private_data;
1022 	struct msghdr msg = {.msg_iter = *to,
1023 			     .msg_iocb = iocb};
1024 	ssize_t res;
1025 
1026 	if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT))
1027 		msg.msg_flags = MSG_DONTWAIT;
1028 
1029 	if (iocb->ki_pos != 0)
1030 		return -ESPIPE;
1031 
1032 	if (!iov_iter_count(to))	/* Match SYS5 behaviour */
1033 		return 0;
1034 
1035 	res = sock_recvmsg(sock, &msg, msg.msg_flags);
1036 	*to = msg.msg_iter;
1037 	return res;
1038 }
1039 
1040 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
1041 {
1042 	struct file *file = iocb->ki_filp;
1043 	struct socket *sock = file->private_data;
1044 	struct msghdr msg = {.msg_iter = *from,
1045 			     .msg_iocb = iocb};
1046 	ssize_t res;
1047 
1048 	if (iocb->ki_pos != 0)
1049 		return -ESPIPE;
1050 
1051 	if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT))
1052 		msg.msg_flags = MSG_DONTWAIT;
1053 
1054 	if (sock->type == SOCK_SEQPACKET)
1055 		msg.msg_flags |= MSG_EOR;
1056 
1057 	res = sock_sendmsg(sock, &msg);
1058 	*from = msg.msg_iter;
1059 	return res;
1060 }
1061 
1062 /*
1063  * Atomic setting of ioctl hooks to avoid race
1064  * with module unload.
1065  */
1066 
1067 static DEFINE_MUTEX(br_ioctl_mutex);
1068 static int (*br_ioctl_hook)(struct net *net, struct net_bridge *br,
1069 			    unsigned int cmd, struct ifreq *ifr,
1070 			    void __user *uarg);
1071 
1072 void brioctl_set(int (*hook)(struct net *net, struct net_bridge *br,
1073 			     unsigned int cmd, struct ifreq *ifr,
1074 			     void __user *uarg))
1075 {
1076 	mutex_lock(&br_ioctl_mutex);
1077 	br_ioctl_hook = hook;
1078 	mutex_unlock(&br_ioctl_mutex);
1079 }
1080 EXPORT_SYMBOL(brioctl_set);
1081 
1082 int br_ioctl_call(struct net *net, struct net_bridge *br, unsigned int cmd,
1083 		  struct ifreq *ifr, void __user *uarg)
1084 {
1085 	int err = -ENOPKG;
1086 
1087 	if (!br_ioctl_hook)
1088 		request_module("bridge");
1089 
1090 	mutex_lock(&br_ioctl_mutex);
1091 	if (br_ioctl_hook)
1092 		err = br_ioctl_hook(net, br, cmd, ifr, uarg);
1093 	mutex_unlock(&br_ioctl_mutex);
1094 
1095 	return err;
1096 }
1097 
1098 static DEFINE_MUTEX(vlan_ioctl_mutex);
1099 static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
1100 
1101 void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
1102 {
1103 	mutex_lock(&vlan_ioctl_mutex);
1104 	vlan_ioctl_hook = hook;
1105 	mutex_unlock(&vlan_ioctl_mutex);
1106 }
1107 EXPORT_SYMBOL(vlan_ioctl_set);
1108 
1109 static long sock_do_ioctl(struct net *net, struct socket *sock,
1110 			  unsigned int cmd, unsigned long arg)
1111 {
1112 	struct ifreq ifr;
1113 	bool need_copyout;
1114 	int err;
1115 	void __user *argp = (void __user *)arg;
1116 	void __user *data;
1117 
1118 	err = sock->ops->ioctl(sock, cmd, arg);
1119 
1120 	/*
1121 	 * If this ioctl is unknown try to hand it down
1122 	 * to the NIC driver.
1123 	 */
1124 	if (err != -ENOIOCTLCMD)
1125 		return err;
1126 
1127 	if (!is_socket_ioctl_cmd(cmd))
1128 		return -ENOTTY;
1129 
1130 	if (get_user_ifreq(&ifr, &data, argp))
1131 		return -EFAULT;
1132 	err = dev_ioctl(net, cmd, &ifr, data, &need_copyout);
1133 	if (!err && need_copyout)
1134 		if (put_user_ifreq(&ifr, argp))
1135 			return -EFAULT;
1136 
1137 	return err;
1138 }
1139 
1140 /*
1141  *	With an ioctl, arg may well be a user mode pointer, but we don't know
1142  *	what to do with it - that's up to the protocol still.
1143  */
1144 
1145 static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
1146 {
1147 	struct socket *sock;
1148 	struct sock *sk;
1149 	void __user *argp = (void __user *)arg;
1150 	int pid, err;
1151 	struct net *net;
1152 
1153 	sock = file->private_data;
1154 	sk = sock->sk;
1155 	net = sock_net(sk);
1156 	if (unlikely(cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))) {
1157 		struct ifreq ifr;
1158 		void __user *data;
1159 		bool need_copyout;
1160 		if (get_user_ifreq(&ifr, &data, argp))
1161 			return -EFAULT;
1162 		err = dev_ioctl(net, cmd, &ifr, data, &need_copyout);
1163 		if (!err && need_copyout)
1164 			if (put_user_ifreq(&ifr, argp))
1165 				return -EFAULT;
1166 	} else
1167 #ifdef CONFIG_WEXT_CORE
1168 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
1169 		err = wext_handle_ioctl(net, cmd, argp);
1170 	} else
1171 #endif
1172 		switch (cmd) {
1173 		case FIOSETOWN:
1174 		case SIOCSPGRP:
1175 			err = -EFAULT;
1176 			if (get_user(pid, (int __user *)argp))
1177 				break;
1178 			err = f_setown(sock->file, pid, 1);
1179 			break;
1180 		case FIOGETOWN:
1181 		case SIOCGPGRP:
1182 			err = put_user(f_getown(sock->file),
1183 				       (int __user *)argp);
1184 			break;
1185 		case SIOCGIFBR:
1186 		case SIOCSIFBR:
1187 		case SIOCBRADDBR:
1188 		case SIOCBRDELBR:
1189 			err = br_ioctl_call(net, NULL, cmd, NULL, argp);
1190 			break;
1191 		case SIOCGIFVLAN:
1192 		case SIOCSIFVLAN:
1193 			err = -ENOPKG;
1194 			if (!vlan_ioctl_hook)
1195 				request_module("8021q");
1196 
1197 			mutex_lock(&vlan_ioctl_mutex);
1198 			if (vlan_ioctl_hook)
1199 				err = vlan_ioctl_hook(net, argp);
1200 			mutex_unlock(&vlan_ioctl_mutex);
1201 			break;
1202 		case SIOCGSKNS:
1203 			err = -EPERM;
1204 			if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1205 				break;
1206 
1207 			err = open_related_ns(&net->ns, get_net_ns);
1208 			break;
1209 		case SIOCGSTAMP_OLD:
1210 		case SIOCGSTAMPNS_OLD:
1211 			if (!sock->ops->gettstamp) {
1212 				err = -ENOIOCTLCMD;
1213 				break;
1214 			}
1215 			err = sock->ops->gettstamp(sock, argp,
1216 						   cmd == SIOCGSTAMP_OLD,
1217 						   !IS_ENABLED(CONFIG_64BIT));
1218 			break;
1219 		case SIOCGSTAMP_NEW:
1220 		case SIOCGSTAMPNS_NEW:
1221 			if (!sock->ops->gettstamp) {
1222 				err = -ENOIOCTLCMD;
1223 				break;
1224 			}
1225 			err = sock->ops->gettstamp(sock, argp,
1226 						   cmd == SIOCGSTAMP_NEW,
1227 						   false);
1228 			break;
1229 
1230 		case SIOCGIFCONF:
1231 			err = dev_ifconf(net, argp);
1232 			break;
1233 
1234 		default:
1235 			err = sock_do_ioctl(net, sock, cmd, arg);
1236 			break;
1237 		}
1238 	return err;
1239 }
1240 
1241 /**
1242  *	sock_create_lite - creates a socket
1243  *	@family: protocol family (AF_INET, ...)
1244  *	@type: communication type (SOCK_STREAM, ...)
1245  *	@protocol: protocol (0, ...)
1246  *	@res: new socket
1247  *
1248  *	Creates a new socket and assigns it to @res, passing through LSM.
1249  *	The new socket initialization is not complete, see kernel_accept().
1250  *	Returns 0 or an error. On failure @res is set to %NULL.
1251  *	This function internally uses GFP_KERNEL.
1252  */
1253 
1254 int sock_create_lite(int family, int type, int protocol, struct socket **res)
1255 {
1256 	int err;
1257 	struct socket *sock = NULL;
1258 
1259 	err = security_socket_create(family, type, protocol, 1);
1260 	if (err)
1261 		goto out;
1262 
1263 	sock = sock_alloc();
1264 	if (!sock) {
1265 		err = -ENOMEM;
1266 		goto out;
1267 	}
1268 
1269 	sock->type = type;
1270 	err = security_socket_post_create(sock, family, type, protocol, 1);
1271 	if (err)
1272 		goto out_release;
1273 
1274 out:
1275 	*res = sock;
1276 	return err;
1277 out_release:
1278 	sock_release(sock);
1279 	sock = NULL;
1280 	goto out;
1281 }
1282 EXPORT_SYMBOL(sock_create_lite);
1283 
1284 /* No kernel lock held - perfect */
1285 static __poll_t sock_poll(struct file *file, poll_table *wait)
1286 {
1287 	struct socket *sock = file->private_data;
1288 	__poll_t events = poll_requested_events(wait), flag = 0;
1289 
1290 	if (!sock->ops->poll)
1291 		return 0;
1292 
1293 	if (sk_can_busy_loop(sock->sk)) {
1294 		/* poll once if requested by the syscall */
1295 		if (events & POLL_BUSY_LOOP)
1296 			sk_busy_loop(sock->sk, 1);
1297 
1298 		/* if this socket can poll_ll, tell the system call */
1299 		flag = POLL_BUSY_LOOP;
1300 	}
1301 
1302 	return sock->ops->poll(file, sock, wait) | flag;
1303 }
1304 
1305 static int sock_mmap(struct file *file, struct vm_area_struct *vma)
1306 {
1307 	struct socket *sock = file->private_data;
1308 
1309 	return sock->ops->mmap(file, sock, vma);
1310 }
1311 
1312 static int sock_close(struct inode *inode, struct file *filp)
1313 {
1314 	__sock_release(SOCKET_I(inode), inode);
1315 	return 0;
1316 }
1317 
1318 /*
1319  *	Update the socket async list
1320  *
1321  *	Fasync_list locking strategy.
1322  *
1323  *	1. fasync_list is modified only under process context socket lock
1324  *	   i.e. under semaphore.
1325  *	2. fasync_list is used under read_lock(&sk->sk_callback_lock)
1326  *	   or under socket lock
1327  */
1328 
1329 static int sock_fasync(int fd, struct file *filp, int on)
1330 {
1331 	struct socket *sock = filp->private_data;
1332 	struct sock *sk = sock->sk;
1333 	struct socket_wq *wq = &sock->wq;
1334 
1335 	if (sk == NULL)
1336 		return -EINVAL;
1337 
1338 	lock_sock(sk);
1339 	fasync_helper(fd, filp, on, &wq->fasync_list);
1340 
1341 	if (!wq->fasync_list)
1342 		sock_reset_flag(sk, SOCK_FASYNC);
1343 	else
1344 		sock_set_flag(sk, SOCK_FASYNC);
1345 
1346 	release_sock(sk);
1347 	return 0;
1348 }
1349 
1350 /* This function may be called only under rcu_lock */
1351 
1352 int sock_wake_async(struct socket_wq *wq, int how, int band)
1353 {
1354 	if (!wq || !wq->fasync_list)
1355 		return -1;
1356 
1357 	switch (how) {
1358 	case SOCK_WAKE_WAITD:
1359 		if (test_bit(SOCKWQ_ASYNC_WAITDATA, &wq->flags))
1360 			break;
1361 		goto call_kill;
1362 	case SOCK_WAKE_SPACE:
1363 		if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags))
1364 			break;
1365 		fallthrough;
1366 	case SOCK_WAKE_IO:
1367 call_kill:
1368 		kill_fasync(&wq->fasync_list, SIGIO, band);
1369 		break;
1370 	case SOCK_WAKE_URG:
1371 		kill_fasync(&wq->fasync_list, SIGURG, band);
1372 	}
1373 
1374 	return 0;
1375 }
1376 EXPORT_SYMBOL(sock_wake_async);
1377 
1378 /**
1379  *	__sock_create - creates a socket
1380  *	@net: net namespace
1381  *	@family: protocol family (AF_INET, ...)
1382  *	@type: communication type (SOCK_STREAM, ...)
1383  *	@protocol: protocol (0, ...)
1384  *	@res: new socket
1385  *	@kern: boolean for kernel space sockets
1386  *
1387  *	Creates a new socket and assigns it to @res, passing through LSM.
1388  *	Returns 0 or an error. On failure @res is set to %NULL. @kern must
1389  *	be set to true if the socket resides in kernel space.
1390  *	This function internally uses GFP_KERNEL.
1391  */
1392 
1393 int __sock_create(struct net *net, int family, int type, int protocol,
1394 			 struct socket **res, int kern)
1395 {
1396 	int err;
1397 	struct socket *sock;
1398 	const struct net_proto_family *pf;
1399 
1400 	/*
1401 	 *      Check protocol is in range
1402 	 */
1403 	if (family < 0 || family >= NPROTO)
1404 		return -EAFNOSUPPORT;
1405 	if (type < 0 || type >= SOCK_MAX)
1406 		return -EINVAL;
1407 
1408 	/* Compatibility.
1409 
1410 	   This uglymoron is moved from INET layer to here to avoid
1411 	   deadlock in module load.
1412 	 */
1413 	if (family == PF_INET && type == SOCK_PACKET) {
1414 		pr_info_once("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
1415 			     current->comm);
1416 		family = PF_PACKET;
1417 	}
1418 
1419 	err = security_socket_create(family, type, protocol, kern);
1420 	if (err)
1421 		return err;
1422 
1423 	/*
1424 	 *	Allocate the socket and allow the family to set things up. if
1425 	 *	the protocol is 0, the family is instructed to select an appropriate
1426 	 *	default.
1427 	 */
1428 	sock = sock_alloc();
1429 	if (!sock) {
1430 		net_warn_ratelimited("socket: no more sockets\n");
1431 		return -ENFILE;	/* Not exactly a match, but its the
1432 				   closest posix thing */
1433 	}
1434 
1435 	sock->type = type;
1436 
1437 #ifdef CONFIG_MODULES
1438 	/* Attempt to load a protocol module if the find failed.
1439 	 *
1440 	 * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
1441 	 * requested real, full-featured networking support upon configuration.
1442 	 * Otherwise module support will break!
1443 	 */
1444 	if (rcu_access_pointer(net_families[family]) == NULL)
1445 		request_module("net-pf-%d", family);
1446 #endif
1447 
1448 	rcu_read_lock();
1449 	pf = rcu_dereference(net_families[family]);
1450 	err = -EAFNOSUPPORT;
1451 	if (!pf)
1452 		goto out_release;
1453 
1454 	/*
1455 	 * We will call the ->create function, that possibly is in a loadable
1456 	 * module, so we have to bump that loadable module refcnt first.
1457 	 */
1458 	if (!try_module_get(pf->owner))
1459 		goto out_release;
1460 
1461 	/* Now protected by module ref count */
1462 	rcu_read_unlock();
1463 
1464 	err = pf->create(net, sock, protocol, kern);
1465 	if (err < 0)
1466 		goto out_module_put;
1467 
1468 	/*
1469 	 * Now to bump the refcnt of the [loadable] module that owns this
1470 	 * socket at sock_release time we decrement its refcnt.
1471 	 */
1472 	if (!try_module_get(sock->ops->owner))
1473 		goto out_module_busy;
1474 
1475 	/*
1476 	 * Now that we're done with the ->create function, the [loadable]
1477 	 * module can have its refcnt decremented
1478 	 */
1479 	module_put(pf->owner);
1480 	err = security_socket_post_create(sock, family, type, protocol, kern);
1481 	if (err)
1482 		goto out_sock_release;
1483 	*res = sock;
1484 
1485 	return 0;
1486 
1487 out_module_busy:
1488 	err = -EAFNOSUPPORT;
1489 out_module_put:
1490 	sock->ops = NULL;
1491 	module_put(pf->owner);
1492 out_sock_release:
1493 	sock_release(sock);
1494 	return err;
1495 
1496 out_release:
1497 	rcu_read_unlock();
1498 	goto out_sock_release;
1499 }
1500 EXPORT_SYMBOL(__sock_create);
1501 
1502 /**
1503  *	sock_create - creates a socket
1504  *	@family: protocol family (AF_INET, ...)
1505  *	@type: communication type (SOCK_STREAM, ...)
1506  *	@protocol: protocol (0, ...)
1507  *	@res: new socket
1508  *
1509  *	A wrapper around __sock_create().
1510  *	Returns 0 or an error. This function internally uses GFP_KERNEL.
1511  */
1512 
1513 int sock_create(int family, int type, int protocol, struct socket **res)
1514 {
1515 	return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
1516 }
1517 EXPORT_SYMBOL(sock_create);
1518 
1519 /**
1520  *	sock_create_kern - creates a socket (kernel space)
1521  *	@net: net namespace
1522  *	@family: protocol family (AF_INET, ...)
1523  *	@type: communication type (SOCK_STREAM, ...)
1524  *	@protocol: protocol (0, ...)
1525  *	@res: new socket
1526  *
1527  *	A wrapper around __sock_create().
1528  *	Returns 0 or an error. This function internally uses GFP_KERNEL.
1529  */
1530 
1531 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
1532 {
1533 	return __sock_create(net, family, type, protocol, res, 1);
1534 }
1535 EXPORT_SYMBOL(sock_create_kern);
1536 
1537 int __sys_socket(int family, int type, int protocol)
1538 {
1539 	int retval;
1540 	struct socket *sock;
1541 	int flags;
1542 
1543 	/* Check the SOCK_* constants for consistency.  */
1544 	BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
1545 	BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
1546 	BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
1547 	BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
1548 
1549 	flags = type & ~SOCK_TYPE_MASK;
1550 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1551 		return -EINVAL;
1552 	type &= SOCK_TYPE_MASK;
1553 
1554 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1555 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1556 
1557 	retval = sock_create(family, type, protocol, &sock);
1558 	if (retval < 0)
1559 		return retval;
1560 
1561 	return sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
1562 }
1563 
1564 SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
1565 {
1566 	return __sys_socket(family, type, protocol);
1567 }
1568 
1569 /*
1570  *	Create a pair of connected sockets.
1571  */
1572 
1573 int __sys_socketpair(int family, int type, int protocol, int __user *usockvec)
1574 {
1575 	struct socket *sock1, *sock2;
1576 	int fd1, fd2, err;
1577 	struct file *newfile1, *newfile2;
1578 	int flags;
1579 
1580 	flags = type & ~SOCK_TYPE_MASK;
1581 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1582 		return -EINVAL;
1583 	type &= SOCK_TYPE_MASK;
1584 
1585 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1586 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1587 
1588 	/*
1589 	 * reserve descriptors and make sure we won't fail
1590 	 * to return them to userland.
1591 	 */
1592 	fd1 = get_unused_fd_flags(flags);
1593 	if (unlikely(fd1 < 0))
1594 		return fd1;
1595 
1596 	fd2 = get_unused_fd_flags(flags);
1597 	if (unlikely(fd2 < 0)) {
1598 		put_unused_fd(fd1);
1599 		return fd2;
1600 	}
1601 
1602 	err = put_user(fd1, &usockvec[0]);
1603 	if (err)
1604 		goto out;
1605 
1606 	err = put_user(fd2, &usockvec[1]);
1607 	if (err)
1608 		goto out;
1609 
1610 	/*
1611 	 * Obtain the first socket and check if the underlying protocol
1612 	 * supports the socketpair call.
1613 	 */
1614 
1615 	err = sock_create(family, type, protocol, &sock1);
1616 	if (unlikely(err < 0))
1617 		goto out;
1618 
1619 	err = sock_create(family, type, protocol, &sock2);
1620 	if (unlikely(err < 0)) {
1621 		sock_release(sock1);
1622 		goto out;
1623 	}
1624 
1625 	err = security_socket_socketpair(sock1, sock2);
1626 	if (unlikely(err)) {
1627 		sock_release(sock2);
1628 		sock_release(sock1);
1629 		goto out;
1630 	}
1631 
1632 	err = sock1->ops->socketpair(sock1, sock2);
1633 	if (unlikely(err < 0)) {
1634 		sock_release(sock2);
1635 		sock_release(sock1);
1636 		goto out;
1637 	}
1638 
1639 	newfile1 = sock_alloc_file(sock1, flags, NULL);
1640 	if (IS_ERR(newfile1)) {
1641 		err = PTR_ERR(newfile1);
1642 		sock_release(sock2);
1643 		goto out;
1644 	}
1645 
1646 	newfile2 = sock_alloc_file(sock2, flags, NULL);
1647 	if (IS_ERR(newfile2)) {
1648 		err = PTR_ERR(newfile2);
1649 		fput(newfile1);
1650 		goto out;
1651 	}
1652 
1653 	audit_fd_pair(fd1, fd2);
1654 
1655 	fd_install(fd1, newfile1);
1656 	fd_install(fd2, newfile2);
1657 	return 0;
1658 
1659 out:
1660 	put_unused_fd(fd2);
1661 	put_unused_fd(fd1);
1662 	return err;
1663 }
1664 
1665 SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
1666 		int __user *, usockvec)
1667 {
1668 	return __sys_socketpair(family, type, protocol, usockvec);
1669 }
1670 
1671 /*
1672  *	Bind a name to a socket. Nothing much to do here since it's
1673  *	the protocol's responsibility to handle the local address.
1674  *
1675  *	We move the socket address to kernel space before we call
1676  *	the protocol layer (having also checked the address is ok).
1677  */
1678 
1679 int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
1680 {
1681 	struct socket *sock;
1682 	struct sockaddr_storage address;
1683 	int err, fput_needed;
1684 
1685 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1686 	if (sock) {
1687 		err = move_addr_to_kernel(umyaddr, addrlen, &address);
1688 		if (!err) {
1689 			err = security_socket_bind(sock,
1690 						   (struct sockaddr *)&address,
1691 						   addrlen);
1692 			if (!err)
1693 				err = sock->ops->bind(sock,
1694 						      (struct sockaddr *)
1695 						      &address, addrlen);
1696 		}
1697 		fput_light(sock->file, fput_needed);
1698 	}
1699 	return err;
1700 }
1701 
1702 SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
1703 {
1704 	return __sys_bind(fd, umyaddr, addrlen);
1705 }
1706 
1707 /*
1708  *	Perform a listen. Basically, we allow the protocol to do anything
1709  *	necessary for a listen, and if that works, we mark the socket as
1710  *	ready for listening.
1711  */
1712 
1713 int __sys_listen(int fd, int backlog)
1714 {
1715 	struct socket *sock;
1716 	int err, fput_needed;
1717 	int somaxconn;
1718 
1719 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1720 	if (sock) {
1721 		somaxconn = sock_net(sock->sk)->core.sysctl_somaxconn;
1722 		if ((unsigned int)backlog > somaxconn)
1723 			backlog = somaxconn;
1724 
1725 		err = security_socket_listen(sock, backlog);
1726 		if (!err)
1727 			err = sock->ops->listen(sock, backlog);
1728 
1729 		fput_light(sock->file, fput_needed);
1730 	}
1731 	return err;
1732 }
1733 
1734 SYSCALL_DEFINE2(listen, int, fd, int, backlog)
1735 {
1736 	return __sys_listen(fd, backlog);
1737 }
1738 
1739 struct file *do_accept(struct file *file, unsigned file_flags,
1740 		       struct sockaddr __user *upeer_sockaddr,
1741 		       int __user *upeer_addrlen, int flags)
1742 {
1743 	struct socket *sock, *newsock;
1744 	struct file *newfile;
1745 	int err, len;
1746 	struct sockaddr_storage address;
1747 
1748 	sock = sock_from_file(file);
1749 	if (!sock)
1750 		return ERR_PTR(-ENOTSOCK);
1751 
1752 	newsock = sock_alloc();
1753 	if (!newsock)
1754 		return ERR_PTR(-ENFILE);
1755 
1756 	newsock->type = sock->type;
1757 	newsock->ops = sock->ops;
1758 
1759 	/*
1760 	 * We don't need try_module_get here, as the listening socket (sock)
1761 	 * has the protocol module (sock->ops->owner) held.
1762 	 */
1763 	__module_get(newsock->ops->owner);
1764 
1765 	newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);
1766 	if (IS_ERR(newfile))
1767 		return newfile;
1768 
1769 	err = security_socket_accept(sock, newsock);
1770 	if (err)
1771 		goto out_fd;
1772 
1773 	err = sock->ops->accept(sock, newsock, sock->file->f_flags | file_flags,
1774 					false);
1775 	if (err < 0)
1776 		goto out_fd;
1777 
1778 	if (upeer_sockaddr) {
1779 		len = newsock->ops->getname(newsock,
1780 					(struct sockaddr *)&address, 2);
1781 		if (len < 0) {
1782 			err = -ECONNABORTED;
1783 			goto out_fd;
1784 		}
1785 		err = move_addr_to_user(&address,
1786 					len, upeer_sockaddr, upeer_addrlen);
1787 		if (err < 0)
1788 			goto out_fd;
1789 	}
1790 
1791 	/* File flags are not inherited via accept() unlike another OSes. */
1792 	return newfile;
1793 out_fd:
1794 	fput(newfile);
1795 	return ERR_PTR(err);
1796 }
1797 
1798 int __sys_accept4_file(struct file *file, unsigned file_flags,
1799 		       struct sockaddr __user *upeer_sockaddr,
1800 		       int __user *upeer_addrlen, int flags,
1801 		       unsigned long nofile)
1802 {
1803 	struct file *newfile;
1804 	int newfd;
1805 
1806 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1807 		return -EINVAL;
1808 
1809 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1810 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1811 
1812 	newfd = __get_unused_fd_flags(flags, nofile);
1813 	if (unlikely(newfd < 0))
1814 		return newfd;
1815 
1816 	newfile = do_accept(file, file_flags, upeer_sockaddr, upeer_addrlen,
1817 			    flags);
1818 	if (IS_ERR(newfile)) {
1819 		put_unused_fd(newfd);
1820 		return PTR_ERR(newfile);
1821 	}
1822 	fd_install(newfd, newfile);
1823 	return newfd;
1824 }
1825 
1826 /*
1827  *	For accept, we attempt to create a new socket, set up the link
1828  *	with the client, wake up the client, then return the new
1829  *	connected fd. We collect the address of the connector in kernel
1830  *	space and move it to user at the very end. This is unclean because
1831  *	we open the socket then return an error.
1832  *
1833  *	1003.1g adds the ability to recvmsg() to query connection pending
1834  *	status to recvmsg. We need to add that support in a way thats
1835  *	clean when we restructure accept also.
1836  */
1837 
1838 int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
1839 		  int __user *upeer_addrlen, int flags)
1840 {
1841 	int ret = -EBADF;
1842 	struct fd f;
1843 
1844 	f = fdget(fd);
1845 	if (f.file) {
1846 		ret = __sys_accept4_file(f.file, 0, upeer_sockaddr,
1847 						upeer_addrlen, flags,
1848 						rlimit(RLIMIT_NOFILE));
1849 		fdput(f);
1850 	}
1851 
1852 	return ret;
1853 }
1854 
1855 SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
1856 		int __user *, upeer_addrlen, int, flags)
1857 {
1858 	return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, flags);
1859 }
1860 
1861 SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
1862 		int __user *, upeer_addrlen)
1863 {
1864 	return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
1865 }
1866 
1867 /*
1868  *	Attempt to connect to a socket with the server address.  The address
1869  *	is in user space so we verify it is OK and move it to kernel space.
1870  *
1871  *	For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
1872  *	break bindings
1873  *
1874  *	NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
1875  *	other SEQPACKET protocols that take time to connect() as it doesn't
1876  *	include the -EINPROGRESS status for such sockets.
1877  */
1878 
1879 int __sys_connect_file(struct file *file, struct sockaddr_storage *address,
1880 		       int addrlen, int file_flags)
1881 {
1882 	struct socket *sock;
1883 	int err;
1884 
1885 	sock = sock_from_file(file);
1886 	if (!sock) {
1887 		err = -ENOTSOCK;
1888 		goto out;
1889 	}
1890 
1891 	err =
1892 	    security_socket_connect(sock, (struct sockaddr *)address, addrlen);
1893 	if (err)
1894 		goto out;
1895 
1896 	err = sock->ops->connect(sock, (struct sockaddr *)address, addrlen,
1897 				 sock->file->f_flags | file_flags);
1898 out:
1899 	return err;
1900 }
1901 
1902 int __sys_connect(int fd, struct sockaddr __user *uservaddr, int addrlen)
1903 {
1904 	int ret = -EBADF;
1905 	struct fd f;
1906 
1907 	f = fdget(fd);
1908 	if (f.file) {
1909 		struct sockaddr_storage address;
1910 
1911 		ret = move_addr_to_kernel(uservaddr, addrlen, &address);
1912 		if (!ret)
1913 			ret = __sys_connect_file(f.file, &address, addrlen, 0);
1914 		fdput(f);
1915 	}
1916 
1917 	return ret;
1918 }
1919 
1920 SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
1921 		int, addrlen)
1922 {
1923 	return __sys_connect(fd, uservaddr, addrlen);
1924 }
1925 
1926 /*
1927  *	Get the local address ('name') of a socket object. Move the obtained
1928  *	name to user space.
1929  */
1930 
1931 int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
1932 		      int __user *usockaddr_len)
1933 {
1934 	struct socket *sock;
1935 	struct sockaddr_storage address;
1936 	int err, fput_needed;
1937 
1938 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1939 	if (!sock)
1940 		goto out;
1941 
1942 	err = security_socket_getsockname(sock);
1943 	if (err)
1944 		goto out_put;
1945 
1946 	err = sock->ops->getname(sock, (struct sockaddr *)&address, 0);
1947 	if (err < 0)
1948 		goto out_put;
1949         /* "err" is actually length in this case */
1950 	err = move_addr_to_user(&address, err, usockaddr, usockaddr_len);
1951 
1952 out_put:
1953 	fput_light(sock->file, fput_needed);
1954 out:
1955 	return err;
1956 }
1957 
1958 SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
1959 		int __user *, usockaddr_len)
1960 {
1961 	return __sys_getsockname(fd, usockaddr, usockaddr_len);
1962 }
1963 
1964 /*
1965  *	Get the remote address ('name') of a socket object. Move the obtained
1966  *	name to user space.
1967  */
1968 
1969 int __sys_getpeername(int fd, struct sockaddr __user *usockaddr,
1970 		      int __user *usockaddr_len)
1971 {
1972 	struct socket *sock;
1973 	struct sockaddr_storage address;
1974 	int err, fput_needed;
1975 
1976 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1977 	if (sock != NULL) {
1978 		err = security_socket_getpeername(sock);
1979 		if (err) {
1980 			fput_light(sock->file, fput_needed);
1981 			return err;
1982 		}
1983 
1984 		err = sock->ops->getname(sock, (struct sockaddr *)&address, 1);
1985 		if (err >= 0)
1986 			/* "err" is actually length in this case */
1987 			err = move_addr_to_user(&address, err, usockaddr,
1988 						usockaddr_len);
1989 		fput_light(sock->file, fput_needed);
1990 	}
1991 	return err;
1992 }
1993 
1994 SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
1995 		int __user *, usockaddr_len)
1996 {
1997 	return __sys_getpeername(fd, usockaddr, usockaddr_len);
1998 }
1999 
2000 /*
2001  *	Send a datagram to a given address. We move the address into kernel
2002  *	space and check the user space data area is readable before invoking
2003  *	the protocol.
2004  */
2005 int __sys_sendto(int fd, void __user *buff, size_t len, unsigned int flags,
2006 		 struct sockaddr __user *addr,  int addr_len)
2007 {
2008 	struct socket *sock;
2009 	struct sockaddr_storage address;
2010 	int err;
2011 	struct msghdr msg;
2012 	struct iovec iov;
2013 	int fput_needed;
2014 
2015 	err = import_single_range(WRITE, buff, len, &iov, &msg.msg_iter);
2016 	if (unlikely(err))
2017 		return err;
2018 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2019 	if (!sock)
2020 		goto out;
2021 
2022 	msg.msg_name = NULL;
2023 	msg.msg_control = NULL;
2024 	msg.msg_controllen = 0;
2025 	msg.msg_namelen = 0;
2026 	if (addr) {
2027 		err = move_addr_to_kernel(addr, addr_len, &address);
2028 		if (err < 0)
2029 			goto out_put;
2030 		msg.msg_name = (struct sockaddr *)&address;
2031 		msg.msg_namelen = addr_len;
2032 	}
2033 	if (sock->file->f_flags & O_NONBLOCK)
2034 		flags |= MSG_DONTWAIT;
2035 	msg.msg_flags = flags;
2036 	err = sock_sendmsg(sock, &msg);
2037 
2038 out_put:
2039 	fput_light(sock->file, fput_needed);
2040 out:
2041 	return err;
2042 }
2043 
2044 SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
2045 		unsigned int, flags, struct sockaddr __user *, addr,
2046 		int, addr_len)
2047 {
2048 	return __sys_sendto(fd, buff, len, flags, addr, addr_len);
2049 }
2050 
2051 /*
2052  *	Send a datagram down a socket.
2053  */
2054 
2055 SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
2056 		unsigned int, flags)
2057 {
2058 	return __sys_sendto(fd, buff, len, flags, NULL, 0);
2059 }
2060 
2061 /*
2062  *	Receive a frame from the socket and optionally record the address of the
2063  *	sender. We verify the buffers are writable and if needed move the
2064  *	sender address from kernel to user space.
2065  */
2066 int __sys_recvfrom(int fd, void __user *ubuf, size_t size, unsigned int flags,
2067 		   struct sockaddr __user *addr, int __user *addr_len)
2068 {
2069 	struct socket *sock;
2070 	struct iovec iov;
2071 	struct msghdr msg;
2072 	struct sockaddr_storage address;
2073 	int err, err2;
2074 	int fput_needed;
2075 
2076 	err = import_single_range(READ, ubuf, size, &iov, &msg.msg_iter);
2077 	if (unlikely(err))
2078 		return err;
2079 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2080 	if (!sock)
2081 		goto out;
2082 
2083 	msg.msg_control = NULL;
2084 	msg.msg_controllen = 0;
2085 	/* Save some cycles and don't copy the address if not needed */
2086 	msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
2087 	/* We assume all kernel code knows the size of sockaddr_storage */
2088 	msg.msg_namelen = 0;
2089 	msg.msg_iocb = NULL;
2090 	msg.msg_flags = 0;
2091 	if (sock->file->f_flags & O_NONBLOCK)
2092 		flags |= MSG_DONTWAIT;
2093 	err = sock_recvmsg(sock, &msg, flags);
2094 
2095 	if (err >= 0 && addr != NULL) {
2096 		err2 = move_addr_to_user(&address,
2097 					 msg.msg_namelen, addr, addr_len);
2098 		if (err2 < 0)
2099 			err = err2;
2100 	}
2101 
2102 	fput_light(sock->file, fput_needed);
2103 out:
2104 	return err;
2105 }
2106 
2107 SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
2108 		unsigned int, flags, struct sockaddr __user *, addr,
2109 		int __user *, addr_len)
2110 {
2111 	return __sys_recvfrom(fd, ubuf, size, flags, addr, addr_len);
2112 }
2113 
2114 /*
2115  *	Receive a datagram from a socket.
2116  */
2117 
2118 SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
2119 		unsigned int, flags)
2120 {
2121 	return __sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
2122 }
2123 
2124 static bool sock_use_custom_sol_socket(const struct socket *sock)
2125 {
2126 	const struct sock *sk = sock->sk;
2127 
2128 	/* Use sock->ops->setsockopt() for MPTCP */
2129 	return IS_ENABLED(CONFIG_MPTCP) &&
2130 	       sk->sk_protocol == IPPROTO_MPTCP &&
2131 	       sk->sk_type == SOCK_STREAM &&
2132 	       (sk->sk_family == AF_INET || sk->sk_family == AF_INET6);
2133 }
2134 
2135 /*
2136  *	Set a socket option. Because we don't know the option lengths we have
2137  *	to pass the user mode parameter for the protocols to sort out.
2138  */
2139 int __sys_setsockopt(int fd, int level, int optname, char __user *user_optval,
2140 		int optlen)
2141 {
2142 	sockptr_t optval = USER_SOCKPTR(user_optval);
2143 	char *kernel_optval = NULL;
2144 	int err, fput_needed;
2145 	struct socket *sock;
2146 
2147 	if (optlen < 0)
2148 		return -EINVAL;
2149 
2150 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2151 	if (!sock)
2152 		return err;
2153 
2154 	err = security_socket_setsockopt(sock, level, optname);
2155 	if (err)
2156 		goto out_put;
2157 
2158 	if (!in_compat_syscall())
2159 		err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level, &optname,
2160 						     user_optval, &optlen,
2161 						     &kernel_optval);
2162 	if (err < 0)
2163 		goto out_put;
2164 	if (err > 0) {
2165 		err = 0;
2166 		goto out_put;
2167 	}
2168 
2169 	if (kernel_optval)
2170 		optval = KERNEL_SOCKPTR(kernel_optval);
2171 	if (level == SOL_SOCKET && !sock_use_custom_sol_socket(sock))
2172 		err = sock_setsockopt(sock, level, optname, optval, optlen);
2173 	else if (unlikely(!sock->ops->setsockopt))
2174 		err = -EOPNOTSUPP;
2175 	else
2176 		err = sock->ops->setsockopt(sock, level, optname, optval,
2177 					    optlen);
2178 	kfree(kernel_optval);
2179 out_put:
2180 	fput_light(sock->file, fput_needed);
2181 	return err;
2182 }
2183 
2184 SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
2185 		char __user *, optval, int, optlen)
2186 {
2187 	return __sys_setsockopt(fd, level, optname, optval, optlen);
2188 }
2189 
2190 INDIRECT_CALLABLE_DECLARE(bool tcp_bpf_bypass_getsockopt(int level,
2191 							 int optname));
2192 
2193 /*
2194  *	Get a socket option. Because we don't know the option lengths we have
2195  *	to pass a user mode parameter for the protocols to sort out.
2196  */
2197 int __sys_getsockopt(int fd, int level, int optname, char __user *optval,
2198 		int __user *optlen)
2199 {
2200 	int err, fput_needed;
2201 	struct socket *sock;
2202 	int max_optlen;
2203 
2204 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2205 	if (!sock)
2206 		return err;
2207 
2208 	err = security_socket_getsockopt(sock, level, optname);
2209 	if (err)
2210 		goto out_put;
2211 
2212 	if (!in_compat_syscall())
2213 		max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
2214 
2215 	if (level == SOL_SOCKET)
2216 		err = sock_getsockopt(sock, level, optname, optval, optlen);
2217 	else if (unlikely(!sock->ops->getsockopt))
2218 		err = -EOPNOTSUPP;
2219 	else
2220 		err = sock->ops->getsockopt(sock, level, optname, optval,
2221 					    optlen);
2222 
2223 	if (!in_compat_syscall())
2224 		err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
2225 						     optval, optlen, max_optlen,
2226 						     err);
2227 out_put:
2228 	fput_light(sock->file, fput_needed);
2229 	return err;
2230 }
2231 
2232 SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
2233 		char __user *, optval, int __user *, optlen)
2234 {
2235 	return __sys_getsockopt(fd, level, optname, optval, optlen);
2236 }
2237 
2238 /*
2239  *	Shutdown a socket.
2240  */
2241 
2242 int __sys_shutdown_sock(struct socket *sock, int how)
2243 {
2244 	int err;
2245 
2246 	err = security_socket_shutdown(sock, how);
2247 	if (!err)
2248 		err = sock->ops->shutdown(sock, how);
2249 
2250 	return err;
2251 }
2252 
2253 int __sys_shutdown(int fd, int how)
2254 {
2255 	int err, fput_needed;
2256 	struct socket *sock;
2257 
2258 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2259 	if (sock != NULL) {
2260 		err = __sys_shutdown_sock(sock, how);
2261 		fput_light(sock->file, fput_needed);
2262 	}
2263 	return err;
2264 }
2265 
2266 SYSCALL_DEFINE2(shutdown, int, fd, int, how)
2267 {
2268 	return __sys_shutdown(fd, how);
2269 }
2270 
2271 /* A couple of helpful macros for getting the address of the 32/64 bit
2272  * fields which are the same type (int / unsigned) on our platforms.
2273  */
2274 #define COMPAT_MSG(msg, member)	((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
2275 #define COMPAT_NAMELEN(msg)	COMPAT_MSG(msg, msg_namelen)
2276 #define COMPAT_FLAGS(msg)	COMPAT_MSG(msg, msg_flags)
2277 
2278 struct used_address {
2279 	struct sockaddr_storage name;
2280 	unsigned int name_len;
2281 };
2282 
2283 int __copy_msghdr_from_user(struct msghdr *kmsg,
2284 			    struct user_msghdr __user *umsg,
2285 			    struct sockaddr __user **save_addr,
2286 			    struct iovec __user **uiov, size_t *nsegs)
2287 {
2288 	struct user_msghdr msg;
2289 	ssize_t err;
2290 
2291 	if (copy_from_user(&msg, umsg, sizeof(*umsg)))
2292 		return -EFAULT;
2293 
2294 	kmsg->msg_control_is_user = true;
2295 	kmsg->msg_control_user = msg.msg_control;
2296 	kmsg->msg_controllen = msg.msg_controllen;
2297 	kmsg->msg_flags = msg.msg_flags;
2298 
2299 	kmsg->msg_namelen = msg.msg_namelen;
2300 	if (!msg.msg_name)
2301 		kmsg->msg_namelen = 0;
2302 
2303 	if (kmsg->msg_namelen < 0)
2304 		return -EINVAL;
2305 
2306 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
2307 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
2308 
2309 	if (save_addr)
2310 		*save_addr = msg.msg_name;
2311 
2312 	if (msg.msg_name && kmsg->msg_namelen) {
2313 		if (!save_addr) {
2314 			err = move_addr_to_kernel(msg.msg_name,
2315 						  kmsg->msg_namelen,
2316 						  kmsg->msg_name);
2317 			if (err < 0)
2318 				return err;
2319 		}
2320 	} else {
2321 		kmsg->msg_name = NULL;
2322 		kmsg->msg_namelen = 0;
2323 	}
2324 
2325 	if (msg.msg_iovlen > UIO_MAXIOV)
2326 		return -EMSGSIZE;
2327 
2328 	kmsg->msg_iocb = NULL;
2329 	*uiov = msg.msg_iov;
2330 	*nsegs = msg.msg_iovlen;
2331 	return 0;
2332 }
2333 
2334 static int copy_msghdr_from_user(struct msghdr *kmsg,
2335 				 struct user_msghdr __user *umsg,
2336 				 struct sockaddr __user **save_addr,
2337 				 struct iovec **iov)
2338 {
2339 	struct user_msghdr msg;
2340 	ssize_t err;
2341 
2342 	err = __copy_msghdr_from_user(kmsg, umsg, save_addr, &msg.msg_iov,
2343 					&msg.msg_iovlen);
2344 	if (err)
2345 		return err;
2346 
2347 	err = import_iovec(save_addr ? READ : WRITE,
2348 			    msg.msg_iov, msg.msg_iovlen,
2349 			    UIO_FASTIOV, iov, &kmsg->msg_iter);
2350 	return err < 0 ? err : 0;
2351 }
2352 
2353 static int ____sys_sendmsg(struct socket *sock, struct msghdr *msg_sys,
2354 			   unsigned int flags, struct used_address *used_address,
2355 			   unsigned int allowed_msghdr_flags)
2356 {
2357 	unsigned char ctl[sizeof(struct cmsghdr) + 20]
2358 				__aligned(sizeof(__kernel_size_t));
2359 	/* 20 is size of ipv6_pktinfo */
2360 	unsigned char *ctl_buf = ctl;
2361 	int ctl_len;
2362 	ssize_t err;
2363 
2364 	err = -ENOBUFS;
2365 
2366 	if (msg_sys->msg_controllen > INT_MAX)
2367 		goto out;
2368 	flags |= (msg_sys->msg_flags & allowed_msghdr_flags);
2369 	ctl_len = msg_sys->msg_controllen;
2370 	if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
2371 		err =
2372 		    cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl,
2373 						     sizeof(ctl));
2374 		if (err)
2375 			goto out;
2376 		ctl_buf = msg_sys->msg_control;
2377 		ctl_len = msg_sys->msg_controllen;
2378 	} else if (ctl_len) {
2379 		BUILD_BUG_ON(sizeof(struct cmsghdr) !=
2380 			     CMSG_ALIGN(sizeof(struct cmsghdr)));
2381 		if (ctl_len > sizeof(ctl)) {
2382 			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
2383 			if (ctl_buf == NULL)
2384 				goto out;
2385 		}
2386 		err = -EFAULT;
2387 		if (copy_from_user(ctl_buf, msg_sys->msg_control_user, ctl_len))
2388 			goto out_freectl;
2389 		msg_sys->msg_control = ctl_buf;
2390 		msg_sys->msg_control_is_user = false;
2391 	}
2392 	msg_sys->msg_flags = flags;
2393 
2394 	if (sock->file->f_flags & O_NONBLOCK)
2395 		msg_sys->msg_flags |= MSG_DONTWAIT;
2396 	/*
2397 	 * If this is sendmmsg() and current destination address is same as
2398 	 * previously succeeded address, omit asking LSM's decision.
2399 	 * used_address->name_len is initialized to UINT_MAX so that the first
2400 	 * destination address never matches.
2401 	 */
2402 	if (used_address && msg_sys->msg_name &&
2403 	    used_address->name_len == msg_sys->msg_namelen &&
2404 	    !memcmp(&used_address->name, msg_sys->msg_name,
2405 		    used_address->name_len)) {
2406 		err = sock_sendmsg_nosec(sock, msg_sys);
2407 		goto out_freectl;
2408 	}
2409 	err = sock_sendmsg(sock, msg_sys);
2410 	/*
2411 	 * If this is sendmmsg() and sending to current destination address was
2412 	 * successful, remember it.
2413 	 */
2414 	if (used_address && err >= 0) {
2415 		used_address->name_len = msg_sys->msg_namelen;
2416 		if (msg_sys->msg_name)
2417 			memcpy(&used_address->name, msg_sys->msg_name,
2418 			       used_address->name_len);
2419 	}
2420 
2421 out_freectl:
2422 	if (ctl_buf != ctl)
2423 		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
2424 out:
2425 	return err;
2426 }
2427 
2428 int sendmsg_copy_msghdr(struct msghdr *msg,
2429 			struct user_msghdr __user *umsg, unsigned flags,
2430 			struct iovec **iov)
2431 {
2432 	int err;
2433 
2434 	if (flags & MSG_CMSG_COMPAT) {
2435 		struct compat_msghdr __user *msg_compat;
2436 
2437 		msg_compat = (struct compat_msghdr __user *) umsg;
2438 		err = get_compat_msghdr(msg, msg_compat, NULL, iov);
2439 	} else {
2440 		err = copy_msghdr_from_user(msg, umsg, NULL, iov);
2441 	}
2442 	if (err < 0)
2443 		return err;
2444 
2445 	return 0;
2446 }
2447 
2448 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
2449 			 struct msghdr *msg_sys, unsigned int flags,
2450 			 struct used_address *used_address,
2451 			 unsigned int allowed_msghdr_flags)
2452 {
2453 	struct sockaddr_storage address;
2454 	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
2455 	ssize_t err;
2456 
2457 	msg_sys->msg_name = &address;
2458 
2459 	err = sendmsg_copy_msghdr(msg_sys, msg, flags, &iov);
2460 	if (err < 0)
2461 		return err;
2462 
2463 	err = ____sys_sendmsg(sock, msg_sys, flags, used_address,
2464 				allowed_msghdr_flags);
2465 	kfree(iov);
2466 	return err;
2467 }
2468 
2469 /*
2470  *	BSD sendmsg interface
2471  */
2472 long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,
2473 			unsigned int flags)
2474 {
2475 	return ____sys_sendmsg(sock, msg, flags, NULL, 0);
2476 }
2477 
2478 long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2479 		   bool forbid_cmsg_compat)
2480 {
2481 	int fput_needed, err;
2482 	struct msghdr msg_sys;
2483 	struct socket *sock;
2484 
2485 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2486 		return -EINVAL;
2487 
2488 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2489 	if (!sock)
2490 		goto out;
2491 
2492 	err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL, 0);
2493 
2494 	fput_light(sock->file, fput_needed);
2495 out:
2496 	return err;
2497 }
2498 
2499 SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
2500 {
2501 	return __sys_sendmsg(fd, msg, flags, true);
2502 }
2503 
2504 /*
2505  *	Linux sendmmsg interface
2506  */
2507 
2508 int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2509 		   unsigned int flags, bool forbid_cmsg_compat)
2510 {
2511 	int fput_needed, err, datagrams;
2512 	struct socket *sock;
2513 	struct mmsghdr __user *entry;
2514 	struct compat_mmsghdr __user *compat_entry;
2515 	struct msghdr msg_sys;
2516 	struct used_address used_address;
2517 	unsigned int oflags = flags;
2518 
2519 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2520 		return -EINVAL;
2521 
2522 	if (vlen > UIO_MAXIOV)
2523 		vlen = UIO_MAXIOV;
2524 
2525 	datagrams = 0;
2526 
2527 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2528 	if (!sock)
2529 		return err;
2530 
2531 	used_address.name_len = UINT_MAX;
2532 	entry = mmsg;
2533 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2534 	err = 0;
2535 	flags |= MSG_BATCH;
2536 
2537 	while (datagrams < vlen) {
2538 		if (datagrams == vlen - 1)
2539 			flags = oflags;
2540 
2541 		if (MSG_CMSG_COMPAT & flags) {
2542 			err = ___sys_sendmsg(sock, (struct user_msghdr __user *)compat_entry,
2543 					     &msg_sys, flags, &used_address, MSG_EOR);
2544 			if (err < 0)
2545 				break;
2546 			err = __put_user(err, &compat_entry->msg_len);
2547 			++compat_entry;
2548 		} else {
2549 			err = ___sys_sendmsg(sock,
2550 					     (struct user_msghdr __user *)entry,
2551 					     &msg_sys, flags, &used_address, MSG_EOR);
2552 			if (err < 0)
2553 				break;
2554 			err = put_user(err, &entry->msg_len);
2555 			++entry;
2556 		}
2557 
2558 		if (err)
2559 			break;
2560 		++datagrams;
2561 		if (msg_data_left(&msg_sys))
2562 			break;
2563 		cond_resched();
2564 	}
2565 
2566 	fput_light(sock->file, fput_needed);
2567 
2568 	/* We only return an error if no datagrams were able to be sent */
2569 	if (datagrams != 0)
2570 		return datagrams;
2571 
2572 	return err;
2573 }
2574 
2575 SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
2576 		unsigned int, vlen, unsigned int, flags)
2577 {
2578 	return __sys_sendmmsg(fd, mmsg, vlen, flags, true);
2579 }
2580 
2581 int recvmsg_copy_msghdr(struct msghdr *msg,
2582 			struct user_msghdr __user *umsg, unsigned flags,
2583 			struct sockaddr __user **uaddr,
2584 			struct iovec **iov)
2585 {
2586 	ssize_t err;
2587 
2588 	if (MSG_CMSG_COMPAT & flags) {
2589 		struct compat_msghdr __user *msg_compat;
2590 
2591 		msg_compat = (struct compat_msghdr __user *) umsg;
2592 		err = get_compat_msghdr(msg, msg_compat, uaddr, iov);
2593 	} else {
2594 		err = copy_msghdr_from_user(msg, umsg, uaddr, iov);
2595 	}
2596 	if (err < 0)
2597 		return err;
2598 
2599 	return 0;
2600 }
2601 
2602 static int ____sys_recvmsg(struct socket *sock, struct msghdr *msg_sys,
2603 			   struct user_msghdr __user *msg,
2604 			   struct sockaddr __user *uaddr,
2605 			   unsigned int flags, int nosec)
2606 {
2607 	struct compat_msghdr __user *msg_compat =
2608 					(struct compat_msghdr __user *) msg;
2609 	int __user *uaddr_len = COMPAT_NAMELEN(msg);
2610 	struct sockaddr_storage addr;
2611 	unsigned long cmsg_ptr;
2612 	int len;
2613 	ssize_t err;
2614 
2615 	msg_sys->msg_name = &addr;
2616 	cmsg_ptr = (unsigned long)msg_sys->msg_control;
2617 	msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
2618 
2619 	/* We assume all kernel code knows the size of sockaddr_storage */
2620 	msg_sys->msg_namelen = 0;
2621 
2622 	if (sock->file->f_flags & O_NONBLOCK)
2623 		flags |= MSG_DONTWAIT;
2624 
2625 	if (unlikely(nosec))
2626 		err = sock_recvmsg_nosec(sock, msg_sys, flags);
2627 	else
2628 		err = sock_recvmsg(sock, msg_sys, flags);
2629 
2630 	if (err < 0)
2631 		goto out;
2632 	len = err;
2633 
2634 	if (uaddr != NULL) {
2635 		err = move_addr_to_user(&addr,
2636 					msg_sys->msg_namelen, uaddr,
2637 					uaddr_len);
2638 		if (err < 0)
2639 			goto out;
2640 	}
2641 	err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
2642 			 COMPAT_FLAGS(msg));
2643 	if (err)
2644 		goto out;
2645 	if (MSG_CMSG_COMPAT & flags)
2646 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2647 				 &msg_compat->msg_controllen);
2648 	else
2649 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2650 				 &msg->msg_controllen);
2651 	if (err)
2652 		goto out;
2653 	err = len;
2654 out:
2655 	return err;
2656 }
2657 
2658 static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
2659 			 struct msghdr *msg_sys, unsigned int flags, int nosec)
2660 {
2661 	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
2662 	/* user mode address pointers */
2663 	struct sockaddr __user *uaddr;
2664 	ssize_t err;
2665 
2666 	err = recvmsg_copy_msghdr(msg_sys, msg, flags, &uaddr, &iov);
2667 	if (err < 0)
2668 		return err;
2669 
2670 	err = ____sys_recvmsg(sock, msg_sys, msg, uaddr, flags, nosec);
2671 	kfree(iov);
2672 	return err;
2673 }
2674 
2675 /*
2676  *	BSD recvmsg interface
2677  */
2678 
2679 long __sys_recvmsg_sock(struct socket *sock, struct msghdr *msg,
2680 			struct user_msghdr __user *umsg,
2681 			struct sockaddr __user *uaddr, unsigned int flags)
2682 {
2683 	return ____sys_recvmsg(sock, msg, umsg, uaddr, flags, 0);
2684 }
2685 
2686 long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2687 		   bool forbid_cmsg_compat)
2688 {
2689 	int fput_needed, err;
2690 	struct msghdr msg_sys;
2691 	struct socket *sock;
2692 
2693 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2694 		return -EINVAL;
2695 
2696 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2697 	if (!sock)
2698 		goto out;
2699 
2700 	err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
2701 
2702 	fput_light(sock->file, fput_needed);
2703 out:
2704 	return err;
2705 }
2706 
2707 SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
2708 		unsigned int, flags)
2709 {
2710 	return __sys_recvmsg(fd, msg, flags, true);
2711 }
2712 
2713 /*
2714  *     Linux recvmmsg interface
2715  */
2716 
2717 static int do_recvmmsg(int fd, struct mmsghdr __user *mmsg,
2718 			  unsigned int vlen, unsigned int flags,
2719 			  struct timespec64 *timeout)
2720 {
2721 	int fput_needed, err, datagrams;
2722 	struct socket *sock;
2723 	struct mmsghdr __user *entry;
2724 	struct compat_mmsghdr __user *compat_entry;
2725 	struct msghdr msg_sys;
2726 	struct timespec64 end_time;
2727 	struct timespec64 timeout64;
2728 
2729 	if (timeout &&
2730 	    poll_select_set_timeout(&end_time, timeout->tv_sec,
2731 				    timeout->tv_nsec))
2732 		return -EINVAL;
2733 
2734 	datagrams = 0;
2735 
2736 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2737 	if (!sock)
2738 		return err;
2739 
2740 	if (likely(!(flags & MSG_ERRQUEUE))) {
2741 		err = sock_error(sock->sk);
2742 		if (err) {
2743 			datagrams = err;
2744 			goto out_put;
2745 		}
2746 	}
2747 
2748 	entry = mmsg;
2749 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2750 
2751 	while (datagrams < vlen) {
2752 		/*
2753 		 * No need to ask LSM for more than the first datagram.
2754 		 */
2755 		if (MSG_CMSG_COMPAT & flags) {
2756 			err = ___sys_recvmsg(sock, (struct user_msghdr __user *)compat_entry,
2757 					     &msg_sys, flags & ~MSG_WAITFORONE,
2758 					     datagrams);
2759 			if (err < 0)
2760 				break;
2761 			err = __put_user(err, &compat_entry->msg_len);
2762 			++compat_entry;
2763 		} else {
2764 			err = ___sys_recvmsg(sock,
2765 					     (struct user_msghdr __user *)entry,
2766 					     &msg_sys, flags & ~MSG_WAITFORONE,
2767 					     datagrams);
2768 			if (err < 0)
2769 				break;
2770 			err = put_user(err, &entry->msg_len);
2771 			++entry;
2772 		}
2773 
2774 		if (err)
2775 			break;
2776 		++datagrams;
2777 
2778 		/* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */
2779 		if (flags & MSG_WAITFORONE)
2780 			flags |= MSG_DONTWAIT;
2781 
2782 		if (timeout) {
2783 			ktime_get_ts64(&timeout64);
2784 			*timeout = timespec64_sub(end_time, timeout64);
2785 			if (timeout->tv_sec < 0) {
2786 				timeout->tv_sec = timeout->tv_nsec = 0;
2787 				break;
2788 			}
2789 
2790 			/* Timeout, return less than vlen datagrams */
2791 			if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
2792 				break;
2793 		}
2794 
2795 		/* Out of band data, return right away */
2796 		if (msg_sys.msg_flags & MSG_OOB)
2797 			break;
2798 		cond_resched();
2799 	}
2800 
2801 	if (err == 0)
2802 		goto out_put;
2803 
2804 	if (datagrams == 0) {
2805 		datagrams = err;
2806 		goto out_put;
2807 	}
2808 
2809 	/*
2810 	 * We may return less entries than requested (vlen) if the
2811 	 * sock is non block and there aren't enough datagrams...
2812 	 */
2813 	if (err != -EAGAIN) {
2814 		/*
2815 		 * ... or  if recvmsg returns an error after we
2816 		 * received some datagrams, where we record the
2817 		 * error to return on the next call or if the
2818 		 * app asks about it using getsockopt(SO_ERROR).
2819 		 */
2820 		sock->sk->sk_err = -err;
2821 	}
2822 out_put:
2823 	fput_light(sock->file, fput_needed);
2824 
2825 	return datagrams;
2826 }
2827 
2828 int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
2829 		   unsigned int vlen, unsigned int flags,
2830 		   struct __kernel_timespec __user *timeout,
2831 		   struct old_timespec32 __user *timeout32)
2832 {
2833 	int datagrams;
2834 	struct timespec64 timeout_sys;
2835 
2836 	if (timeout && get_timespec64(&timeout_sys, timeout))
2837 		return -EFAULT;
2838 
2839 	if (timeout32 && get_old_timespec32(&timeout_sys, timeout32))
2840 		return -EFAULT;
2841 
2842 	if (!timeout && !timeout32)
2843 		return do_recvmmsg(fd, mmsg, vlen, flags, NULL);
2844 
2845 	datagrams = do_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
2846 
2847 	if (datagrams <= 0)
2848 		return datagrams;
2849 
2850 	if (timeout && put_timespec64(&timeout_sys, timeout))
2851 		datagrams = -EFAULT;
2852 
2853 	if (timeout32 && put_old_timespec32(&timeout_sys, timeout32))
2854 		datagrams = -EFAULT;
2855 
2856 	return datagrams;
2857 }
2858 
2859 SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
2860 		unsigned int, vlen, unsigned int, flags,
2861 		struct __kernel_timespec __user *, timeout)
2862 {
2863 	if (flags & MSG_CMSG_COMPAT)
2864 		return -EINVAL;
2865 
2866 	return __sys_recvmmsg(fd, mmsg, vlen, flags, timeout, NULL);
2867 }
2868 
2869 #ifdef CONFIG_COMPAT_32BIT_TIME
2870 SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct mmsghdr __user *, mmsg,
2871 		unsigned int, vlen, unsigned int, flags,
2872 		struct old_timespec32 __user *, timeout)
2873 {
2874 	if (flags & MSG_CMSG_COMPAT)
2875 		return -EINVAL;
2876 
2877 	return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL, timeout);
2878 }
2879 #endif
2880 
2881 #ifdef __ARCH_WANT_SYS_SOCKETCALL
2882 /* Argument list sizes for sys_socketcall */
2883 #define AL(x) ((x) * sizeof(unsigned long))
2884 static const unsigned char nargs[21] = {
2885 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
2886 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
2887 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
2888 	AL(4), AL(5), AL(4)
2889 };
2890 
2891 #undef AL
2892 
2893 /*
2894  *	System call vectors.
2895  *
2896  *	Argument checking cleaned up. Saved 20% in size.
2897  *  This function doesn't need to set the kernel lock because
2898  *  it is set by the callees.
2899  */
2900 
2901 SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
2902 {
2903 	unsigned long a[AUDITSC_ARGS];
2904 	unsigned long a0, a1;
2905 	int err;
2906 	unsigned int len;
2907 
2908 	if (call < 1 || call > SYS_SENDMMSG)
2909 		return -EINVAL;
2910 	call = array_index_nospec(call, SYS_SENDMMSG + 1);
2911 
2912 	len = nargs[call];
2913 	if (len > sizeof(a))
2914 		return -EINVAL;
2915 
2916 	/* copy_from_user should be SMP safe. */
2917 	if (copy_from_user(a, args, len))
2918 		return -EFAULT;
2919 
2920 	err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
2921 	if (err)
2922 		return err;
2923 
2924 	a0 = a[0];
2925 	a1 = a[1];
2926 
2927 	switch (call) {
2928 	case SYS_SOCKET:
2929 		err = __sys_socket(a0, a1, a[2]);
2930 		break;
2931 	case SYS_BIND:
2932 		err = __sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
2933 		break;
2934 	case SYS_CONNECT:
2935 		err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
2936 		break;
2937 	case SYS_LISTEN:
2938 		err = __sys_listen(a0, a1);
2939 		break;
2940 	case SYS_ACCEPT:
2941 		err = __sys_accept4(a0, (struct sockaddr __user *)a1,
2942 				    (int __user *)a[2], 0);
2943 		break;
2944 	case SYS_GETSOCKNAME:
2945 		err =
2946 		    __sys_getsockname(a0, (struct sockaddr __user *)a1,
2947 				      (int __user *)a[2]);
2948 		break;
2949 	case SYS_GETPEERNAME:
2950 		err =
2951 		    __sys_getpeername(a0, (struct sockaddr __user *)a1,
2952 				      (int __user *)a[2]);
2953 		break;
2954 	case SYS_SOCKETPAIR:
2955 		err = __sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
2956 		break;
2957 	case SYS_SEND:
2958 		err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
2959 				   NULL, 0);
2960 		break;
2961 	case SYS_SENDTO:
2962 		err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
2963 				   (struct sockaddr __user *)a[4], a[5]);
2964 		break;
2965 	case SYS_RECV:
2966 		err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2967 				     NULL, NULL);
2968 		break;
2969 	case SYS_RECVFROM:
2970 		err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2971 				     (struct sockaddr __user *)a[4],
2972 				     (int __user *)a[5]);
2973 		break;
2974 	case SYS_SHUTDOWN:
2975 		err = __sys_shutdown(a0, a1);
2976 		break;
2977 	case SYS_SETSOCKOPT:
2978 		err = __sys_setsockopt(a0, a1, a[2], (char __user *)a[3],
2979 				       a[4]);
2980 		break;
2981 	case SYS_GETSOCKOPT:
2982 		err =
2983 		    __sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
2984 				     (int __user *)a[4]);
2985 		break;
2986 	case SYS_SENDMSG:
2987 		err = __sys_sendmsg(a0, (struct user_msghdr __user *)a1,
2988 				    a[2], true);
2989 		break;
2990 	case SYS_SENDMMSG:
2991 		err = __sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2],
2992 				     a[3], true);
2993 		break;
2994 	case SYS_RECVMSG:
2995 		err = __sys_recvmsg(a0, (struct user_msghdr __user *)a1,
2996 				    a[2], true);
2997 		break;
2998 	case SYS_RECVMMSG:
2999 		if (IS_ENABLED(CONFIG_64BIT))
3000 			err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
3001 					     a[2], a[3],
3002 					     (struct __kernel_timespec __user *)a[4],
3003 					     NULL);
3004 		else
3005 			err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
3006 					     a[2], a[3], NULL,
3007 					     (struct old_timespec32 __user *)a[4]);
3008 		break;
3009 	case SYS_ACCEPT4:
3010 		err = __sys_accept4(a0, (struct sockaddr __user *)a1,
3011 				    (int __user *)a[2], a[3]);
3012 		break;
3013 	default:
3014 		err = -EINVAL;
3015 		break;
3016 	}
3017 	return err;
3018 }
3019 
3020 #endif				/* __ARCH_WANT_SYS_SOCKETCALL */
3021 
3022 /**
3023  *	sock_register - add a socket protocol handler
3024  *	@ops: description of protocol
3025  *
3026  *	This function is called by a protocol handler that wants to
3027  *	advertise its address family, and have it linked into the
3028  *	socket interface. The value ops->family corresponds to the
3029  *	socket system call protocol family.
3030  */
3031 int sock_register(const struct net_proto_family *ops)
3032 {
3033 	int err;
3034 
3035 	if (ops->family >= NPROTO) {
3036 		pr_crit("protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
3037 		return -ENOBUFS;
3038 	}
3039 
3040 	spin_lock(&net_family_lock);
3041 	if (rcu_dereference_protected(net_families[ops->family],
3042 				      lockdep_is_held(&net_family_lock)))
3043 		err = -EEXIST;
3044 	else {
3045 		rcu_assign_pointer(net_families[ops->family], ops);
3046 		err = 0;
3047 	}
3048 	spin_unlock(&net_family_lock);
3049 
3050 	pr_info("NET: Registered %s protocol family\n", pf_family_names[ops->family]);
3051 	return err;
3052 }
3053 EXPORT_SYMBOL(sock_register);
3054 
3055 /**
3056  *	sock_unregister - remove a protocol handler
3057  *	@family: protocol family to remove
3058  *
3059  *	This function is called by a protocol handler that wants to
3060  *	remove its address family, and have it unlinked from the
3061  *	new socket creation.
3062  *
3063  *	If protocol handler is a module, then it can use module reference
3064  *	counts to protect against new references. If protocol handler is not
3065  *	a module then it needs to provide its own protection in
3066  *	the ops->create routine.
3067  */
3068 void sock_unregister(int family)
3069 {
3070 	BUG_ON(family < 0 || family >= NPROTO);
3071 
3072 	spin_lock(&net_family_lock);
3073 	RCU_INIT_POINTER(net_families[family], NULL);
3074 	spin_unlock(&net_family_lock);
3075 
3076 	synchronize_rcu();
3077 
3078 	pr_info("NET: Unregistered %s protocol family\n", pf_family_names[family]);
3079 }
3080 EXPORT_SYMBOL(sock_unregister);
3081 
3082 bool sock_is_registered(int family)
3083 {
3084 	return family < NPROTO && rcu_access_pointer(net_families[family]);
3085 }
3086 
3087 static int __init sock_init(void)
3088 {
3089 	int err;
3090 	/*
3091 	 *      Initialize the network sysctl infrastructure.
3092 	 */
3093 	err = net_sysctl_init();
3094 	if (err)
3095 		goto out;
3096 
3097 	/*
3098 	 *      Initialize skbuff SLAB cache
3099 	 */
3100 	skb_init();
3101 
3102 	/*
3103 	 *      Initialize the protocols module.
3104 	 */
3105 
3106 	init_inodecache();
3107 
3108 	err = register_filesystem(&sock_fs_type);
3109 	if (err)
3110 		goto out;
3111 	sock_mnt = kern_mount(&sock_fs_type);
3112 	if (IS_ERR(sock_mnt)) {
3113 		err = PTR_ERR(sock_mnt);
3114 		goto out_mount;
3115 	}
3116 
3117 	/* The real protocol initialization is performed in later initcalls.
3118 	 */
3119 
3120 #ifdef CONFIG_NETFILTER
3121 	err = netfilter_init();
3122 	if (err)
3123 		goto out;
3124 #endif
3125 
3126 	ptp_classifier_init();
3127 
3128 out:
3129 	return err;
3130 
3131 out_mount:
3132 	unregister_filesystem(&sock_fs_type);
3133 	goto out;
3134 }
3135 
3136 core_initcall(sock_init);	/* early initcall */
3137 
3138 #ifdef CONFIG_PROC_FS
3139 void socket_seq_show(struct seq_file *seq)
3140 {
3141 	seq_printf(seq, "sockets: used %d\n",
3142 		   sock_inuse_get(seq->private));
3143 }
3144 #endif				/* CONFIG_PROC_FS */
3145 
3146 /* Handle the fact that while struct ifreq has the same *layout* on
3147  * 32/64 for everything but ifreq::ifru_ifmap and ifreq::ifru_data,
3148  * which are handled elsewhere, it still has different *size* due to
3149  * ifreq::ifru_ifmap (which is 16 bytes on 32 bit, 24 bytes on 64-bit,
3150  * resulting in struct ifreq being 32 and 40 bytes respectively).
3151  * As a result, if the struct happens to be at the end of a page and
3152  * the next page isn't readable/writable, we get a fault. To prevent
3153  * that, copy back and forth to the full size.
3154  */
3155 int get_user_ifreq(struct ifreq *ifr, void __user **ifrdata, void __user *arg)
3156 {
3157 	if (in_compat_syscall()) {
3158 		struct compat_ifreq *ifr32 = (struct compat_ifreq *)ifr;
3159 
3160 		memset(ifr, 0, sizeof(*ifr));
3161 		if (copy_from_user(ifr32, arg, sizeof(*ifr32)))
3162 			return -EFAULT;
3163 
3164 		if (ifrdata)
3165 			*ifrdata = compat_ptr(ifr32->ifr_data);
3166 
3167 		return 0;
3168 	}
3169 
3170 	if (copy_from_user(ifr, arg, sizeof(*ifr)))
3171 		return -EFAULT;
3172 
3173 	if (ifrdata)
3174 		*ifrdata = ifr->ifr_data;
3175 
3176 	return 0;
3177 }
3178 EXPORT_SYMBOL(get_user_ifreq);
3179 
3180 int put_user_ifreq(struct ifreq *ifr, void __user *arg)
3181 {
3182 	size_t size = sizeof(*ifr);
3183 
3184 	if (in_compat_syscall())
3185 		size = sizeof(struct compat_ifreq);
3186 
3187 	if (copy_to_user(arg, ifr, size))
3188 		return -EFAULT;
3189 
3190 	return 0;
3191 }
3192 EXPORT_SYMBOL(put_user_ifreq);
3193 
3194 #ifdef CONFIG_COMPAT
3195 static int compat_siocwandev(struct net *net, struct compat_ifreq __user *uifr32)
3196 {
3197 	compat_uptr_t uptr32;
3198 	struct ifreq ifr;
3199 	void __user *saved;
3200 	int err;
3201 
3202 	if (get_user_ifreq(&ifr, NULL, uifr32))
3203 		return -EFAULT;
3204 
3205 	if (get_user(uptr32, &uifr32->ifr_settings.ifs_ifsu))
3206 		return -EFAULT;
3207 
3208 	saved = ifr.ifr_settings.ifs_ifsu.raw_hdlc;
3209 	ifr.ifr_settings.ifs_ifsu.raw_hdlc = compat_ptr(uptr32);
3210 
3211 	err = dev_ioctl(net, SIOCWANDEV, &ifr, NULL, NULL);
3212 	if (!err) {
3213 		ifr.ifr_settings.ifs_ifsu.raw_hdlc = saved;
3214 		if (put_user_ifreq(&ifr, uifr32))
3215 			err = -EFAULT;
3216 	}
3217 	return err;
3218 }
3219 
3220 /* Handle ioctls that use ifreq::ifr_data and just need struct ifreq converted */
3221 static int compat_ifr_data_ioctl(struct net *net, unsigned int cmd,
3222 				 struct compat_ifreq __user *u_ifreq32)
3223 {
3224 	struct ifreq ifreq;
3225 	void __user *data;
3226 
3227 	if (!is_socket_ioctl_cmd(cmd))
3228 		return -ENOTTY;
3229 	if (get_user_ifreq(&ifreq, &data, u_ifreq32))
3230 		return -EFAULT;
3231 	ifreq.ifr_data = data;
3232 
3233 	return dev_ioctl(net, cmd, &ifreq, data, NULL);
3234 }
3235 
3236 /* Since old style bridge ioctl's endup using SIOCDEVPRIVATE
3237  * for some operations; this forces use of the newer bridge-utils that
3238  * use compatible ioctls
3239  */
3240 static int old_bridge_ioctl(compat_ulong_t __user *argp)
3241 {
3242 	compat_ulong_t tmp;
3243 
3244 	if (get_user(tmp, argp))
3245 		return -EFAULT;
3246 	if (tmp == BRCTL_GET_VERSION)
3247 		return BRCTL_VERSION + 1;
3248 	return -EINVAL;
3249 }
3250 
3251 static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
3252 			 unsigned int cmd, unsigned long arg)
3253 {
3254 	void __user *argp = compat_ptr(arg);
3255 	struct sock *sk = sock->sk;
3256 	struct net *net = sock_net(sk);
3257 
3258 	if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))
3259 		return sock_ioctl(file, cmd, (unsigned long)argp);
3260 
3261 	switch (cmd) {
3262 	case SIOCSIFBR:
3263 	case SIOCGIFBR:
3264 		return old_bridge_ioctl(argp);
3265 	case SIOCWANDEV:
3266 		return compat_siocwandev(net, argp);
3267 	case SIOCGSTAMP_OLD:
3268 	case SIOCGSTAMPNS_OLD:
3269 		if (!sock->ops->gettstamp)
3270 			return -ENOIOCTLCMD;
3271 		return sock->ops->gettstamp(sock, argp, cmd == SIOCGSTAMP_OLD,
3272 					    !COMPAT_USE_64BIT_TIME);
3273 
3274 	case SIOCETHTOOL:
3275 	case SIOCBONDSLAVEINFOQUERY:
3276 	case SIOCBONDINFOQUERY:
3277 	case SIOCSHWTSTAMP:
3278 	case SIOCGHWTSTAMP:
3279 		return compat_ifr_data_ioctl(net, cmd, argp);
3280 
3281 	case FIOSETOWN:
3282 	case SIOCSPGRP:
3283 	case FIOGETOWN:
3284 	case SIOCGPGRP:
3285 	case SIOCBRADDBR:
3286 	case SIOCBRDELBR:
3287 	case SIOCGIFVLAN:
3288 	case SIOCSIFVLAN:
3289 	case SIOCGSKNS:
3290 	case SIOCGSTAMP_NEW:
3291 	case SIOCGSTAMPNS_NEW:
3292 	case SIOCGIFCONF:
3293 		return sock_ioctl(file, cmd, arg);
3294 
3295 	case SIOCGIFFLAGS:
3296 	case SIOCSIFFLAGS:
3297 	case SIOCGIFMAP:
3298 	case SIOCSIFMAP:
3299 	case SIOCGIFMETRIC:
3300 	case SIOCSIFMETRIC:
3301 	case SIOCGIFMTU:
3302 	case SIOCSIFMTU:
3303 	case SIOCGIFMEM:
3304 	case SIOCSIFMEM:
3305 	case SIOCGIFHWADDR:
3306 	case SIOCSIFHWADDR:
3307 	case SIOCADDMULTI:
3308 	case SIOCDELMULTI:
3309 	case SIOCGIFINDEX:
3310 	case SIOCGIFADDR:
3311 	case SIOCSIFADDR:
3312 	case SIOCSIFHWBROADCAST:
3313 	case SIOCDIFADDR:
3314 	case SIOCGIFBRDADDR:
3315 	case SIOCSIFBRDADDR:
3316 	case SIOCGIFDSTADDR:
3317 	case SIOCSIFDSTADDR:
3318 	case SIOCGIFNETMASK:
3319 	case SIOCSIFNETMASK:
3320 	case SIOCSIFPFLAGS:
3321 	case SIOCGIFPFLAGS:
3322 	case SIOCGIFTXQLEN:
3323 	case SIOCSIFTXQLEN:
3324 	case SIOCBRADDIF:
3325 	case SIOCBRDELIF:
3326 	case SIOCGIFNAME:
3327 	case SIOCSIFNAME:
3328 	case SIOCGMIIPHY:
3329 	case SIOCGMIIREG:
3330 	case SIOCSMIIREG:
3331 	case SIOCBONDENSLAVE:
3332 	case SIOCBONDRELEASE:
3333 	case SIOCBONDSETHWADDR:
3334 	case SIOCBONDCHANGEACTIVE:
3335 	case SIOCSARP:
3336 	case SIOCGARP:
3337 	case SIOCDARP:
3338 	case SIOCOUTQ:
3339 	case SIOCOUTQNSD:
3340 	case SIOCATMARK:
3341 		return sock_do_ioctl(net, sock, cmd, arg);
3342 	}
3343 
3344 	return -ENOIOCTLCMD;
3345 }
3346 
3347 static long compat_sock_ioctl(struct file *file, unsigned int cmd,
3348 			      unsigned long arg)
3349 {
3350 	struct socket *sock = file->private_data;
3351 	int ret = -ENOIOCTLCMD;
3352 	struct sock *sk;
3353 	struct net *net;
3354 
3355 	sk = sock->sk;
3356 	net = sock_net(sk);
3357 
3358 	if (sock->ops->compat_ioctl)
3359 		ret = sock->ops->compat_ioctl(sock, cmd, arg);
3360 
3361 	if (ret == -ENOIOCTLCMD &&
3362 	    (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
3363 		ret = compat_wext_handle_ioctl(net, cmd, arg);
3364 
3365 	if (ret == -ENOIOCTLCMD)
3366 		ret = compat_sock_ioctl_trans(file, sock, cmd, arg);
3367 
3368 	return ret;
3369 }
3370 #endif
3371 
3372 /**
3373  *	kernel_bind - bind an address to a socket (kernel space)
3374  *	@sock: socket
3375  *	@addr: address
3376  *	@addrlen: length of address
3377  *
3378  *	Returns 0 or an error.
3379  */
3380 
3381 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
3382 {
3383 	return sock->ops->bind(sock, addr, addrlen);
3384 }
3385 EXPORT_SYMBOL(kernel_bind);
3386 
3387 /**
3388  *	kernel_listen - move socket to listening state (kernel space)
3389  *	@sock: socket
3390  *	@backlog: pending connections queue size
3391  *
3392  *	Returns 0 or an error.
3393  */
3394 
3395 int kernel_listen(struct socket *sock, int backlog)
3396 {
3397 	return sock->ops->listen(sock, backlog);
3398 }
3399 EXPORT_SYMBOL(kernel_listen);
3400 
3401 /**
3402  *	kernel_accept - accept a connection (kernel space)
3403  *	@sock: listening socket
3404  *	@newsock: new connected socket
3405  *	@flags: flags
3406  *
3407  *	@flags must be SOCK_CLOEXEC, SOCK_NONBLOCK or 0.
3408  *	If it fails, @newsock is guaranteed to be %NULL.
3409  *	Returns 0 or an error.
3410  */
3411 
3412 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
3413 {
3414 	struct sock *sk = sock->sk;
3415 	int err;
3416 
3417 	err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
3418 			       newsock);
3419 	if (err < 0)
3420 		goto done;
3421 
3422 	err = sock->ops->accept(sock, *newsock, flags, true);
3423 	if (err < 0) {
3424 		sock_release(*newsock);
3425 		*newsock = NULL;
3426 		goto done;
3427 	}
3428 
3429 	(*newsock)->ops = sock->ops;
3430 	__module_get((*newsock)->ops->owner);
3431 
3432 done:
3433 	return err;
3434 }
3435 EXPORT_SYMBOL(kernel_accept);
3436 
3437 /**
3438  *	kernel_connect - connect a socket (kernel space)
3439  *	@sock: socket
3440  *	@addr: address
3441  *	@addrlen: address length
3442  *	@flags: flags (O_NONBLOCK, ...)
3443  *
3444  *	For datagram sockets, @addr is the address to which datagrams are sent
3445  *	by default, and the only address from which datagrams are received.
3446  *	For stream sockets, attempts to connect to @addr.
3447  *	Returns 0 or an error code.
3448  */
3449 
3450 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
3451 		   int flags)
3452 {
3453 	return sock->ops->connect(sock, addr, addrlen, flags);
3454 }
3455 EXPORT_SYMBOL(kernel_connect);
3456 
3457 /**
3458  *	kernel_getsockname - get the address which the socket is bound (kernel space)
3459  *	@sock: socket
3460  *	@addr: address holder
3461  *
3462  * 	Fills the @addr pointer with the address which the socket is bound.
3463  *	Returns 0 or an error code.
3464  */
3465 
3466 int kernel_getsockname(struct socket *sock, struct sockaddr *addr)
3467 {
3468 	return sock->ops->getname(sock, addr, 0);
3469 }
3470 EXPORT_SYMBOL(kernel_getsockname);
3471 
3472 /**
3473  *	kernel_getpeername - get the address which the socket is connected (kernel space)
3474  *	@sock: socket
3475  *	@addr: address holder
3476  *
3477  * 	Fills the @addr pointer with the address which the socket is connected.
3478  *	Returns 0 or an error code.
3479  */
3480 
3481 int kernel_getpeername(struct socket *sock, struct sockaddr *addr)
3482 {
3483 	return sock->ops->getname(sock, addr, 1);
3484 }
3485 EXPORT_SYMBOL(kernel_getpeername);
3486 
3487 /**
3488  *	kernel_sendpage - send a &page through a socket (kernel space)
3489  *	@sock: socket
3490  *	@page: page
3491  *	@offset: page offset
3492  *	@size: total size in bytes
3493  *	@flags: flags (MSG_DONTWAIT, ...)
3494  *
3495  *	Returns the total amount sent in bytes or an error.
3496  */
3497 
3498 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
3499 		    size_t size, int flags)
3500 {
3501 	if (sock->ops->sendpage) {
3502 		/* Warn in case the improper page to zero-copy send */
3503 		WARN_ONCE(!sendpage_ok(page), "improper page for zero-copy send");
3504 		return sock->ops->sendpage(sock, page, offset, size, flags);
3505 	}
3506 	return sock_no_sendpage(sock, page, offset, size, flags);
3507 }
3508 EXPORT_SYMBOL(kernel_sendpage);
3509 
3510 /**
3511  *	kernel_sendpage_locked - send a &page through the locked sock (kernel space)
3512  *	@sk: sock
3513  *	@page: page
3514  *	@offset: page offset
3515  *	@size: total size in bytes
3516  *	@flags: flags (MSG_DONTWAIT, ...)
3517  *
3518  *	Returns the total amount sent in bytes or an error.
3519  *	Caller must hold @sk.
3520  */
3521 
3522 int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
3523 			   size_t size, int flags)
3524 {
3525 	struct socket *sock = sk->sk_socket;
3526 
3527 	if (sock->ops->sendpage_locked)
3528 		return sock->ops->sendpage_locked(sk, page, offset, size,
3529 						  flags);
3530 
3531 	return sock_no_sendpage_locked(sk, page, offset, size, flags);
3532 }
3533 EXPORT_SYMBOL(kernel_sendpage_locked);
3534 
3535 /**
3536  *	kernel_sock_shutdown - shut down part of a full-duplex connection (kernel space)
3537  *	@sock: socket
3538  *	@how: connection part
3539  *
3540  *	Returns 0 or an error.
3541  */
3542 
3543 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
3544 {
3545 	return sock->ops->shutdown(sock, how);
3546 }
3547 EXPORT_SYMBOL(kernel_sock_shutdown);
3548 
3549 /**
3550  *	kernel_sock_ip_overhead - returns the IP overhead imposed by a socket
3551  *	@sk: socket
3552  *
3553  *	This routine returns the IP overhead imposed by a socket i.e.
3554  *	the length of the underlying IP header, depending on whether
3555  *	this is an IPv4 or IPv6 socket and the length from IP options turned
3556  *	on at the socket. Assumes that the caller has a lock on the socket.
3557  */
3558 
3559 u32 kernel_sock_ip_overhead(struct sock *sk)
3560 {
3561 	struct inet_sock *inet;
3562 	struct ip_options_rcu *opt;
3563 	u32 overhead = 0;
3564 #if IS_ENABLED(CONFIG_IPV6)
3565 	struct ipv6_pinfo *np;
3566 	struct ipv6_txoptions *optv6 = NULL;
3567 #endif /* IS_ENABLED(CONFIG_IPV6) */
3568 
3569 	if (!sk)
3570 		return overhead;
3571 
3572 	switch (sk->sk_family) {
3573 	case AF_INET:
3574 		inet = inet_sk(sk);
3575 		overhead += sizeof(struct iphdr);
3576 		opt = rcu_dereference_protected(inet->inet_opt,
3577 						sock_owned_by_user(sk));
3578 		if (opt)
3579 			overhead += opt->opt.optlen;
3580 		return overhead;
3581 #if IS_ENABLED(CONFIG_IPV6)
3582 	case AF_INET6:
3583 		np = inet6_sk(sk);
3584 		overhead += sizeof(struct ipv6hdr);
3585 		if (np)
3586 			optv6 = rcu_dereference_protected(np->opt,
3587 							  sock_owned_by_user(sk));
3588 		if (optv6)
3589 			overhead += (optv6->opt_flen + optv6->opt_nflen);
3590 		return overhead;
3591 #endif /* IS_ENABLED(CONFIG_IPV6) */
3592 	default: /* Returns 0 overhead if the socket is not ipv4 or ipv6 */
3593 		return overhead;
3594 	}
3595 }
3596 EXPORT_SYMBOL(kernel_sock_ip_overhead);
3597