xref: /linux/net/socket.c (revision e6f2a617ac53bc0753b885ffb94379ff48b2e2df)
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/mm.h>
56 #include <linux/socket.h>
57 #include <linux/file.h>
58 #include <linux/net.h>
59 #include <linux/interrupt.h>
60 #include <linux/thread_info.h>
61 #include <linux/rcupdate.h>
62 #include <linux/netdevice.h>
63 #include <linux/proc_fs.h>
64 #include <linux/seq_file.h>
65 #include <linux/mutex.h>
66 #include <linux/if_bridge.h>
67 #include <linux/if_frad.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 
108 #ifdef CONFIG_NET_RX_BUSY_POLL
109 unsigned int sysctl_net_busy_read __read_mostly;
110 unsigned int sysctl_net_busy_poll __read_mostly;
111 #endif
112 
113 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to);
114 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
115 static int sock_mmap(struct file *file, struct vm_area_struct *vma);
116 
117 static int sock_close(struct inode *inode, struct file *file);
118 static __poll_t sock_poll(struct file *file,
119 			      struct poll_table_struct *wait);
120 static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
121 #ifdef CONFIG_COMPAT
122 static long compat_sock_ioctl(struct file *file,
123 			      unsigned int cmd, unsigned long arg);
124 #endif
125 static int sock_fasync(int fd, struct file *filp, int on);
126 static ssize_t sock_sendpage(struct file *file, struct page *page,
127 			     int offset, size_t size, loff_t *ppos, int more);
128 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
129 				struct pipe_inode_info *pipe, size_t len,
130 				unsigned int flags);
131 
132 /*
133  *	Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
134  *	in the operation structures but are done directly via the socketcall() multiplexor.
135  */
136 
137 static const struct file_operations socket_file_ops = {
138 	.owner =	THIS_MODULE,
139 	.llseek =	no_llseek,
140 	.read_iter =	sock_read_iter,
141 	.write_iter =	sock_write_iter,
142 	.poll =		sock_poll,
143 	.unlocked_ioctl = sock_ioctl,
144 #ifdef CONFIG_COMPAT
145 	.compat_ioctl = compat_sock_ioctl,
146 #endif
147 	.mmap =		sock_mmap,
148 	.release =	sock_close,
149 	.fasync =	sock_fasync,
150 	.sendpage =	sock_sendpage,
151 	.splice_write = generic_splice_sendpage,
152 	.splice_read =	sock_splice_read,
153 };
154 
155 /*
156  *	The protocol list. Each protocol is registered in here.
157  */
158 
159 static DEFINE_SPINLOCK(net_family_lock);
160 static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
161 
162 /*
163  * Support routines.
164  * Move socket addresses back and forth across the kernel/user
165  * divide and look after the messy bits.
166  */
167 
168 /**
169  *	move_addr_to_kernel	-	copy a socket address into kernel space
170  *	@uaddr: Address in user space
171  *	@kaddr: Address in kernel space
172  *	@ulen: Length in user space
173  *
174  *	The address is copied into kernel space. If the provided address is
175  *	too long an error code of -EINVAL is returned. If the copy gives
176  *	invalid addresses -EFAULT is returned. On a success 0 is returned.
177  */
178 
179 int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
180 {
181 	if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
182 		return -EINVAL;
183 	if (ulen == 0)
184 		return 0;
185 	if (copy_from_user(kaddr, uaddr, ulen))
186 		return -EFAULT;
187 	return audit_sockaddr(ulen, kaddr);
188 }
189 
190 /**
191  *	move_addr_to_user	-	copy an address to user space
192  *	@kaddr: kernel space address
193  *	@klen: length of address in kernel
194  *	@uaddr: user space address
195  *	@ulen: pointer to user length field
196  *
197  *	The value pointed to by ulen on entry is the buffer length available.
198  *	This is overwritten with the buffer space used. -EINVAL is returned
199  *	if an overlong buffer is specified or a negative buffer size. -EFAULT
200  *	is returned if either the buffer or the length field are not
201  *	accessible.
202  *	After copying the data up to the limit the user specifies, the true
203  *	length of the data is written over the length limit the user
204  *	specified. Zero is returned for a success.
205  */
206 
207 static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
208 			     void __user *uaddr, int __user *ulen)
209 {
210 	int err;
211 	int len;
212 
213 	BUG_ON(klen > sizeof(struct sockaddr_storage));
214 	err = get_user(len, ulen);
215 	if (err)
216 		return err;
217 	if (len > klen)
218 		len = klen;
219 	if (len < 0)
220 		return -EINVAL;
221 	if (len) {
222 		if (audit_sockaddr(klen, kaddr))
223 			return -ENOMEM;
224 		if (copy_to_user(uaddr, kaddr, len))
225 			return -EFAULT;
226 	}
227 	/*
228 	 *      "fromlen shall refer to the value before truncation.."
229 	 *                      1003.1g
230 	 */
231 	return __put_user(klen, ulen);
232 }
233 
234 static struct kmem_cache *sock_inode_cachep __ro_after_init;
235 
236 static struct inode *sock_alloc_inode(struct super_block *sb)
237 {
238 	struct socket_alloc *ei;
239 
240 	ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
241 	if (!ei)
242 		return NULL;
243 	init_waitqueue_head(&ei->socket.wq.wait);
244 	ei->socket.wq.fasync_list = NULL;
245 	ei->socket.wq.flags = 0;
246 
247 	ei->socket.state = SS_UNCONNECTED;
248 	ei->socket.flags = 0;
249 	ei->socket.ops = NULL;
250 	ei->socket.sk = NULL;
251 	ei->socket.file = NULL;
252 
253 	return &ei->vfs_inode;
254 }
255 
256 static void sock_free_inode(struct inode *inode)
257 {
258 	struct socket_alloc *ei;
259 
260 	ei = container_of(inode, struct socket_alloc, vfs_inode);
261 	kmem_cache_free(sock_inode_cachep, ei);
262 }
263 
264 static void init_once(void *foo)
265 {
266 	struct socket_alloc *ei = (struct socket_alloc *)foo;
267 
268 	inode_init_once(&ei->vfs_inode);
269 }
270 
271 static void init_inodecache(void)
272 {
273 	sock_inode_cachep = kmem_cache_create("sock_inode_cache",
274 					      sizeof(struct socket_alloc),
275 					      0,
276 					      (SLAB_HWCACHE_ALIGN |
277 					       SLAB_RECLAIM_ACCOUNT |
278 					       SLAB_MEM_SPREAD | SLAB_ACCOUNT),
279 					      init_once);
280 	BUG_ON(sock_inode_cachep == NULL);
281 }
282 
283 static const struct super_operations sockfs_ops = {
284 	.alloc_inode	= sock_alloc_inode,
285 	.free_inode	= sock_free_inode,
286 	.statfs		= simple_statfs,
287 };
288 
289 /*
290  * sockfs_dname() is called from d_path().
291  */
292 static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
293 {
294 	return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",
295 				d_inode(dentry)->i_ino);
296 }
297 
298 static const struct dentry_operations sockfs_dentry_operations = {
299 	.d_dname  = sockfs_dname,
300 };
301 
302 static int sockfs_xattr_get(const struct xattr_handler *handler,
303 			    struct dentry *dentry, struct inode *inode,
304 			    const char *suffix, void *value, size_t size)
305 {
306 	if (value) {
307 		if (dentry->d_name.len + 1 > size)
308 			return -ERANGE;
309 		memcpy(value, dentry->d_name.name, dentry->d_name.len + 1);
310 	}
311 	return dentry->d_name.len + 1;
312 }
313 
314 #define XATTR_SOCKPROTONAME_SUFFIX "sockprotoname"
315 #define XATTR_NAME_SOCKPROTONAME (XATTR_SYSTEM_PREFIX XATTR_SOCKPROTONAME_SUFFIX)
316 #define XATTR_NAME_SOCKPROTONAME_LEN (sizeof(XATTR_NAME_SOCKPROTONAME)-1)
317 
318 static const struct xattr_handler sockfs_xattr_handler = {
319 	.name = XATTR_NAME_SOCKPROTONAME,
320 	.get = sockfs_xattr_get,
321 };
322 
323 static int sockfs_security_xattr_set(const struct xattr_handler *handler,
324 				     struct dentry *dentry, struct inode *inode,
325 				     const char *suffix, const void *value,
326 				     size_t size, int flags)
327 {
328 	/* Handled by LSM. */
329 	return -EAGAIN;
330 }
331 
332 static const struct xattr_handler sockfs_security_xattr_handler = {
333 	.prefix = XATTR_SECURITY_PREFIX,
334 	.set = sockfs_security_xattr_set,
335 };
336 
337 static const struct xattr_handler *sockfs_xattr_handlers[] = {
338 	&sockfs_xattr_handler,
339 	&sockfs_security_xattr_handler,
340 	NULL
341 };
342 
343 static int sockfs_init_fs_context(struct fs_context *fc)
344 {
345 	struct pseudo_fs_context *ctx = init_pseudo(fc, SOCKFS_MAGIC);
346 	if (!ctx)
347 		return -ENOMEM;
348 	ctx->ops = &sockfs_ops;
349 	ctx->dops = &sockfs_dentry_operations;
350 	ctx->xattr = sockfs_xattr_handlers;
351 	return 0;
352 }
353 
354 static struct vfsmount *sock_mnt __read_mostly;
355 
356 static struct file_system_type sock_fs_type = {
357 	.name =		"sockfs",
358 	.init_fs_context = sockfs_init_fs_context,
359 	.kill_sb =	kill_anon_super,
360 };
361 
362 /*
363  *	Obtains the first available file descriptor and sets it up for use.
364  *
365  *	These functions create file structures and maps them to fd space
366  *	of the current process. On success it returns file descriptor
367  *	and file struct implicitly stored in sock->file.
368  *	Note that another thread may close file descriptor before we return
369  *	from this function. We use the fact that now we do not refer
370  *	to socket after mapping. If one day we will need it, this
371  *	function will increment ref. count on file by 1.
372  *
373  *	In any case returned fd MAY BE not valid!
374  *	This race condition is unavoidable
375  *	with shared fd spaces, we cannot solve it inside kernel,
376  *	but we take care of internal coherence yet.
377  */
378 
379 /**
380  *	sock_alloc_file - Bind a &socket to a &file
381  *	@sock: socket
382  *	@flags: file status flags
383  *	@dname: protocol name
384  *
385  *	Returns the &file bound with @sock, implicitly storing it
386  *	in sock->file. If dname is %NULL, sets to "".
387  *	On failure the return is a ERR pointer (see linux/err.h).
388  *	This function uses GFP_KERNEL internally.
389  */
390 
391 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
392 {
393 	struct file *file;
394 
395 	if (!dname)
396 		dname = sock->sk ? sock->sk->sk_prot_creator->name : "";
397 
398 	file = alloc_file_pseudo(SOCK_INODE(sock), sock_mnt, dname,
399 				O_RDWR | (flags & O_NONBLOCK),
400 				&socket_file_ops);
401 	if (IS_ERR(file)) {
402 		sock_release(sock);
403 		return file;
404 	}
405 
406 	sock->file = file;
407 	file->private_data = sock;
408 	stream_open(SOCK_INODE(sock), file);
409 	return file;
410 }
411 EXPORT_SYMBOL(sock_alloc_file);
412 
413 static int sock_map_fd(struct socket *sock, int flags)
414 {
415 	struct file *newfile;
416 	int fd = get_unused_fd_flags(flags);
417 	if (unlikely(fd < 0)) {
418 		sock_release(sock);
419 		return fd;
420 	}
421 
422 	newfile = sock_alloc_file(sock, flags, NULL);
423 	if (!IS_ERR(newfile)) {
424 		fd_install(fd, newfile);
425 		return fd;
426 	}
427 
428 	put_unused_fd(fd);
429 	return PTR_ERR(newfile);
430 }
431 
432 /**
433  *	sock_from_file - Return the &socket bounded to @file.
434  *	@file: file
435  *	@err: pointer to an error code return
436  *
437  *	On failure returns %NULL and assigns -ENOTSOCK to @err.
438  */
439 
440 struct socket *sock_from_file(struct file *file, int *err)
441 {
442 	if (file->f_op == &socket_file_ops)
443 		return file->private_data;	/* set in sock_map_fd */
444 
445 	*err = -ENOTSOCK;
446 	return NULL;
447 }
448 EXPORT_SYMBOL(sock_from_file);
449 
450 /**
451  *	sockfd_lookup - Go from a file number to its socket slot
452  *	@fd: file handle
453  *	@err: pointer to an error code return
454  *
455  *	The file handle passed in is locked and the socket it is bound
456  *	to is returned. If an error occurs the err pointer is overwritten
457  *	with a negative errno code and NULL is returned. The function checks
458  *	for both invalid handles and passing a handle which is not a socket.
459  *
460  *	On a success the socket object pointer is returned.
461  */
462 
463 struct socket *sockfd_lookup(int fd, int *err)
464 {
465 	struct file *file;
466 	struct socket *sock;
467 
468 	file = fget(fd);
469 	if (!file) {
470 		*err = -EBADF;
471 		return NULL;
472 	}
473 
474 	sock = sock_from_file(file, err);
475 	if (!sock)
476 		fput(file);
477 	return sock;
478 }
479 EXPORT_SYMBOL(sockfd_lookup);
480 
481 static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
482 {
483 	struct fd f = fdget(fd);
484 	struct socket *sock;
485 
486 	*err = -EBADF;
487 	if (f.file) {
488 		sock = sock_from_file(f.file, err);
489 		if (likely(sock)) {
490 			*fput_needed = f.flags;
491 			return sock;
492 		}
493 		fdput(f);
494 	}
495 	return NULL;
496 }
497 
498 static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
499 				size_t size)
500 {
501 	ssize_t len;
502 	ssize_t used = 0;
503 
504 	len = security_inode_listsecurity(d_inode(dentry), buffer, size);
505 	if (len < 0)
506 		return len;
507 	used += len;
508 	if (buffer) {
509 		if (size < used)
510 			return -ERANGE;
511 		buffer += len;
512 	}
513 
514 	len = (XATTR_NAME_SOCKPROTONAME_LEN + 1);
515 	used += len;
516 	if (buffer) {
517 		if (size < used)
518 			return -ERANGE;
519 		memcpy(buffer, XATTR_NAME_SOCKPROTONAME, len);
520 		buffer += len;
521 	}
522 
523 	return used;
524 }
525 
526 static int sockfs_setattr(struct dentry *dentry, struct iattr *iattr)
527 {
528 	int err = simple_setattr(dentry, iattr);
529 
530 	if (!err && (iattr->ia_valid & ATTR_UID)) {
531 		struct socket *sock = SOCKET_I(d_inode(dentry));
532 
533 		if (sock->sk)
534 			sock->sk->sk_uid = iattr->ia_uid;
535 		else
536 			err = -ENOENT;
537 	}
538 
539 	return err;
540 }
541 
542 static const struct inode_operations sockfs_inode_ops = {
543 	.listxattr = sockfs_listxattr,
544 	.setattr = sockfs_setattr,
545 };
546 
547 /**
548  *	sock_alloc - allocate a socket
549  *
550  *	Allocate a new inode and socket object. The two are bound together
551  *	and initialised. The socket is then returned. If we are out of inodes
552  *	NULL is returned. This functions uses GFP_KERNEL internally.
553  */
554 
555 struct socket *sock_alloc(void)
556 {
557 	struct inode *inode;
558 	struct socket *sock;
559 
560 	inode = new_inode_pseudo(sock_mnt->mnt_sb);
561 	if (!inode)
562 		return NULL;
563 
564 	sock = SOCKET_I(inode);
565 
566 	inode->i_ino = get_next_ino();
567 	inode->i_mode = S_IFSOCK | S_IRWXUGO;
568 	inode->i_uid = current_fsuid();
569 	inode->i_gid = current_fsgid();
570 	inode->i_op = &sockfs_inode_ops;
571 
572 	return sock;
573 }
574 EXPORT_SYMBOL(sock_alloc);
575 
576 /**
577  *	sock_release - close a socket
578  *	@sock: socket to close
579  *
580  *	The socket is released from the protocol stack if it has a release
581  *	callback, and the inode is then released if the socket is bound to
582  *	an inode not a file.
583  */
584 
585 static void __sock_release(struct socket *sock, struct inode *inode)
586 {
587 	if (sock->ops) {
588 		struct module *owner = sock->ops->owner;
589 
590 		if (inode)
591 			inode_lock(inode);
592 		sock->ops->release(sock);
593 		sock->sk = NULL;
594 		if (inode)
595 			inode_unlock(inode);
596 		sock->ops = NULL;
597 		module_put(owner);
598 	}
599 
600 	if (sock->wq.fasync_list)
601 		pr_err("%s: fasync list not empty!\n", __func__);
602 
603 	if (!sock->file) {
604 		iput(SOCK_INODE(sock));
605 		return;
606 	}
607 	sock->file = NULL;
608 }
609 
610 void sock_release(struct socket *sock)
611 {
612 	__sock_release(sock, NULL);
613 }
614 EXPORT_SYMBOL(sock_release);
615 
616 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
617 {
618 	u8 flags = *tx_flags;
619 
620 	if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE)
621 		flags |= SKBTX_HW_TSTAMP;
622 
623 	if (tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)
624 		flags |= SKBTX_SW_TSTAMP;
625 
626 	if (tsflags & SOF_TIMESTAMPING_TX_SCHED)
627 		flags |= SKBTX_SCHED_TSTAMP;
628 
629 	*tx_flags = flags;
630 }
631 EXPORT_SYMBOL(__sock_tx_timestamp);
632 
633 INDIRECT_CALLABLE_DECLARE(int inet_sendmsg(struct socket *, struct msghdr *,
634 					   size_t));
635 INDIRECT_CALLABLE_DECLARE(int inet6_sendmsg(struct socket *, struct msghdr *,
636 					    size_t));
637 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
638 {
639 	int ret = INDIRECT_CALL_INET(sock->ops->sendmsg, inet6_sendmsg,
640 				     inet_sendmsg, sock, msg,
641 				     msg_data_left(msg));
642 	BUG_ON(ret == -EIOCBQUEUED);
643 	return ret;
644 }
645 
646 /**
647  *	sock_sendmsg - send a message through @sock
648  *	@sock: socket
649  *	@msg: message to send
650  *
651  *	Sends @msg through @sock, passing through LSM.
652  *	Returns the number of bytes sent, or an error code.
653  */
654 int sock_sendmsg(struct socket *sock, struct msghdr *msg)
655 {
656 	int err = security_socket_sendmsg(sock, msg,
657 					  msg_data_left(msg));
658 
659 	return err ?: sock_sendmsg_nosec(sock, msg);
660 }
661 EXPORT_SYMBOL(sock_sendmsg);
662 
663 /**
664  *	kernel_sendmsg - send a message through @sock (kernel-space)
665  *	@sock: socket
666  *	@msg: message header
667  *	@vec: kernel vec
668  *	@num: vec array length
669  *	@size: total message data size
670  *
671  *	Builds the message data with @vec and sends it through @sock.
672  *	Returns the number of bytes sent, or an error code.
673  */
674 
675 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
676 		   struct kvec *vec, size_t num, size_t size)
677 {
678 	iov_iter_kvec(&msg->msg_iter, WRITE, vec, num, size);
679 	return sock_sendmsg(sock, msg);
680 }
681 EXPORT_SYMBOL(kernel_sendmsg);
682 
683 /**
684  *	kernel_sendmsg_locked - send a message through @sock (kernel-space)
685  *	@sk: sock
686  *	@msg: message header
687  *	@vec: output s/g array
688  *	@num: output s/g array length
689  *	@size: total message data size
690  *
691  *	Builds the message data with @vec and sends it through @sock.
692  *	Returns the number of bytes sent, or an error code.
693  *	Caller must hold @sk.
694  */
695 
696 int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
697 			  struct kvec *vec, size_t num, size_t size)
698 {
699 	struct socket *sock = sk->sk_socket;
700 
701 	if (!sock->ops->sendmsg_locked)
702 		return sock_no_sendmsg_locked(sk, msg, size);
703 
704 	iov_iter_kvec(&msg->msg_iter, WRITE, vec, num, size);
705 
706 	return sock->ops->sendmsg_locked(sk, msg, msg_data_left(msg));
707 }
708 EXPORT_SYMBOL(kernel_sendmsg_locked);
709 
710 static bool skb_is_err_queue(const struct sk_buff *skb)
711 {
712 	/* pkt_type of skbs enqueued on the error queue are set to
713 	 * PACKET_OUTGOING in skb_set_err_queue(). This is only safe to do
714 	 * in recvmsg, since skbs received on a local socket will never
715 	 * have a pkt_type of PACKET_OUTGOING.
716 	 */
717 	return skb->pkt_type == PACKET_OUTGOING;
718 }
719 
720 /* On transmit, software and hardware timestamps are returned independently.
721  * As the two skb clones share the hardware timestamp, which may be updated
722  * before the software timestamp is received, a hardware TX timestamp may be
723  * returned only if there is no software TX timestamp. Ignore false software
724  * timestamps, which may be made in the __sock_recv_timestamp() call when the
725  * option SO_TIMESTAMP_OLD(NS) is enabled on the socket, even when the skb has a
726  * hardware timestamp.
727  */
728 static bool skb_is_swtx_tstamp(const struct sk_buff *skb, int false_tstamp)
729 {
730 	return skb->tstamp && !false_tstamp && skb_is_err_queue(skb);
731 }
732 
733 static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb)
734 {
735 	struct scm_ts_pktinfo ts_pktinfo;
736 	struct net_device *orig_dev;
737 
738 	if (!skb_mac_header_was_set(skb))
739 		return;
740 
741 	memset(&ts_pktinfo, 0, sizeof(ts_pktinfo));
742 
743 	rcu_read_lock();
744 	orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
745 	if (orig_dev)
746 		ts_pktinfo.if_index = orig_dev->ifindex;
747 	rcu_read_unlock();
748 
749 	ts_pktinfo.pkt_length = skb->len - skb_mac_offset(skb);
750 	put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
751 		 sizeof(ts_pktinfo), &ts_pktinfo);
752 }
753 
754 /*
755  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
756  */
757 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
758 	struct sk_buff *skb)
759 {
760 	int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
761 	int new_tstamp = sock_flag(sk, SOCK_TSTAMP_NEW);
762 	struct scm_timestamping_internal tss;
763 
764 	int empty = 1, false_tstamp = 0;
765 	struct skb_shared_hwtstamps *shhwtstamps =
766 		skb_hwtstamps(skb);
767 
768 	/* Race occurred between timestamp enabling and packet
769 	   receiving.  Fill in the current time for now. */
770 	if (need_software_tstamp && skb->tstamp == 0) {
771 		__net_timestamp(skb);
772 		false_tstamp = 1;
773 	}
774 
775 	if (need_software_tstamp) {
776 		if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
777 			if (new_tstamp) {
778 				struct __kernel_sock_timeval tv;
779 
780 				skb_get_new_timestamp(skb, &tv);
781 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_NEW,
782 					 sizeof(tv), &tv);
783 			} else {
784 				struct __kernel_old_timeval tv;
785 
786 				skb_get_timestamp(skb, &tv);
787 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD,
788 					 sizeof(tv), &tv);
789 			}
790 		} else {
791 			if (new_tstamp) {
792 				struct __kernel_timespec ts;
793 
794 				skb_get_new_timestampns(skb, &ts);
795 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_NEW,
796 					 sizeof(ts), &ts);
797 			} else {
798 				struct __kernel_old_timespec ts;
799 
800 				skb_get_timestampns(skb, &ts);
801 				put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_OLD,
802 					 sizeof(ts), &ts);
803 			}
804 		}
805 	}
806 
807 	memset(&tss, 0, sizeof(tss));
808 	if ((sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
809 	    ktime_to_timespec64_cond(skb->tstamp, tss.ts + 0))
810 		empty = 0;
811 	if (shhwtstamps &&
812 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
813 	    !skb_is_swtx_tstamp(skb, false_tstamp) &&
814 	    ktime_to_timespec64_cond(shhwtstamps->hwtstamp, tss.ts + 2)) {
815 		empty = 0;
816 		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
817 		    !skb_is_err_queue(skb))
818 			put_ts_pktinfo(msg, skb);
819 	}
820 	if (!empty) {
821 		if (sock_flag(sk, SOCK_TSTAMP_NEW))
822 			put_cmsg_scm_timestamping64(msg, &tss);
823 		else
824 			put_cmsg_scm_timestamping(msg, &tss);
825 
826 		if (skb_is_err_queue(skb) && skb->len &&
827 		    SKB_EXT_ERR(skb)->opt_stats)
828 			put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS,
829 				 skb->len, skb->data);
830 	}
831 }
832 EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
833 
834 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
835 	struct sk_buff *skb)
836 {
837 	int ack;
838 
839 	if (!sock_flag(sk, SOCK_WIFI_STATUS))
840 		return;
841 	if (!skb->wifi_acked_valid)
842 		return;
843 
844 	ack = skb->wifi_acked;
845 
846 	put_cmsg(msg, SOL_SOCKET, SCM_WIFI_STATUS, sizeof(ack), &ack);
847 }
848 EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
849 
850 static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
851 				   struct sk_buff *skb)
852 {
853 	if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
854 		put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
855 			sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
856 }
857 
858 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
859 	struct sk_buff *skb)
860 {
861 	sock_recv_timestamp(msg, sk, skb);
862 	sock_recv_drops(msg, sk, skb);
863 }
864 EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops);
865 
866 INDIRECT_CALLABLE_DECLARE(int inet_recvmsg(struct socket *, struct msghdr *,
867 					   size_t, int));
868 INDIRECT_CALLABLE_DECLARE(int inet6_recvmsg(struct socket *, struct msghdr *,
869 					    size_t, int));
870 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
871 				     int flags)
872 {
873 	return INDIRECT_CALL_INET(sock->ops->recvmsg, inet6_recvmsg,
874 				  inet_recvmsg, sock, msg, msg_data_left(msg),
875 				  flags);
876 }
877 
878 /**
879  *	sock_recvmsg - receive a message from @sock
880  *	@sock: socket
881  *	@msg: message to receive
882  *	@flags: message flags
883  *
884  *	Receives @msg from @sock, passing through LSM. Returns the total number
885  *	of bytes received, or an error.
886  */
887 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
888 {
889 	int err = security_socket_recvmsg(sock, msg, msg_data_left(msg), flags);
890 
891 	return err ?: sock_recvmsg_nosec(sock, msg, flags);
892 }
893 EXPORT_SYMBOL(sock_recvmsg);
894 
895 /**
896  *	kernel_recvmsg - Receive a message from a socket (kernel space)
897  *	@sock: The socket to receive the message from
898  *	@msg: Received message
899  *	@vec: Input s/g array for message data
900  *	@num: Size of input s/g array
901  *	@size: Number of bytes to read
902  *	@flags: Message flags (MSG_DONTWAIT, etc...)
903  *
904  *	On return the msg structure contains the scatter/gather array passed in the
905  *	vec argument. The array is modified so that it consists of the unfilled
906  *	portion of the original array.
907  *
908  *	The returned value is the total number of bytes received, or an error.
909  */
910 
911 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
912 		   struct kvec *vec, size_t num, size_t size, int flags)
913 {
914 	mm_segment_t oldfs = get_fs();
915 	int result;
916 
917 	iov_iter_kvec(&msg->msg_iter, READ, vec, num, size);
918 	set_fs(KERNEL_DS);
919 	result = sock_recvmsg(sock, msg, flags);
920 	set_fs(oldfs);
921 	return result;
922 }
923 EXPORT_SYMBOL(kernel_recvmsg);
924 
925 static ssize_t sock_sendpage(struct file *file, struct page *page,
926 			     int offset, size_t size, loff_t *ppos, int more)
927 {
928 	struct socket *sock;
929 	int flags;
930 
931 	sock = file->private_data;
932 
933 	flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
934 	/* more is a combination of MSG_MORE and MSG_SENDPAGE_NOTLAST */
935 	flags |= more;
936 
937 	return kernel_sendpage(sock, page, offset, size, flags);
938 }
939 
940 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
941 				struct pipe_inode_info *pipe, size_t len,
942 				unsigned int flags)
943 {
944 	struct socket *sock = file->private_data;
945 
946 	if (unlikely(!sock->ops->splice_read))
947 		return generic_file_splice_read(file, ppos, pipe, len, flags);
948 
949 	return sock->ops->splice_read(sock, ppos, pipe, len, flags);
950 }
951 
952 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
953 {
954 	struct file *file = iocb->ki_filp;
955 	struct socket *sock = file->private_data;
956 	struct msghdr msg = {.msg_iter = *to,
957 			     .msg_iocb = iocb};
958 	ssize_t res;
959 
960 	if (file->f_flags & O_NONBLOCK)
961 		msg.msg_flags = MSG_DONTWAIT;
962 
963 	if (iocb->ki_pos != 0)
964 		return -ESPIPE;
965 
966 	if (!iov_iter_count(to))	/* Match SYS5 behaviour */
967 		return 0;
968 
969 	res = sock_recvmsg(sock, &msg, msg.msg_flags);
970 	*to = msg.msg_iter;
971 	return res;
972 }
973 
974 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
975 {
976 	struct file *file = iocb->ki_filp;
977 	struct socket *sock = file->private_data;
978 	struct msghdr msg = {.msg_iter = *from,
979 			     .msg_iocb = iocb};
980 	ssize_t res;
981 
982 	if (iocb->ki_pos != 0)
983 		return -ESPIPE;
984 
985 	if (file->f_flags & O_NONBLOCK)
986 		msg.msg_flags = MSG_DONTWAIT;
987 
988 	if (sock->type == SOCK_SEQPACKET)
989 		msg.msg_flags |= MSG_EOR;
990 
991 	res = sock_sendmsg(sock, &msg);
992 	*from = msg.msg_iter;
993 	return res;
994 }
995 
996 /*
997  * Atomic setting of ioctl hooks to avoid race
998  * with module unload.
999  */
1000 
1001 static DEFINE_MUTEX(br_ioctl_mutex);
1002 static int (*br_ioctl_hook) (struct net *, unsigned int cmd, void __user *arg);
1003 
1004 void brioctl_set(int (*hook) (struct net *, unsigned int, void __user *))
1005 {
1006 	mutex_lock(&br_ioctl_mutex);
1007 	br_ioctl_hook = hook;
1008 	mutex_unlock(&br_ioctl_mutex);
1009 }
1010 EXPORT_SYMBOL(brioctl_set);
1011 
1012 static DEFINE_MUTEX(vlan_ioctl_mutex);
1013 static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
1014 
1015 void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
1016 {
1017 	mutex_lock(&vlan_ioctl_mutex);
1018 	vlan_ioctl_hook = hook;
1019 	mutex_unlock(&vlan_ioctl_mutex);
1020 }
1021 EXPORT_SYMBOL(vlan_ioctl_set);
1022 
1023 static DEFINE_MUTEX(dlci_ioctl_mutex);
1024 static int (*dlci_ioctl_hook) (unsigned int, void __user *);
1025 
1026 void dlci_ioctl_set(int (*hook) (unsigned int, void __user *))
1027 {
1028 	mutex_lock(&dlci_ioctl_mutex);
1029 	dlci_ioctl_hook = hook;
1030 	mutex_unlock(&dlci_ioctl_mutex);
1031 }
1032 EXPORT_SYMBOL(dlci_ioctl_set);
1033 
1034 static long sock_do_ioctl(struct net *net, struct socket *sock,
1035 			  unsigned int cmd, unsigned long arg)
1036 {
1037 	int err;
1038 	void __user *argp = (void __user *)arg;
1039 
1040 	err = sock->ops->ioctl(sock, cmd, arg);
1041 
1042 	/*
1043 	 * If this ioctl is unknown try to hand it down
1044 	 * to the NIC driver.
1045 	 */
1046 	if (err != -ENOIOCTLCMD)
1047 		return err;
1048 
1049 	if (cmd == SIOCGIFCONF) {
1050 		struct ifconf ifc;
1051 		if (copy_from_user(&ifc, argp, sizeof(struct ifconf)))
1052 			return -EFAULT;
1053 		rtnl_lock();
1054 		err = dev_ifconf(net, &ifc, sizeof(struct ifreq));
1055 		rtnl_unlock();
1056 		if (!err && copy_to_user(argp, &ifc, sizeof(struct ifconf)))
1057 			err = -EFAULT;
1058 	} else {
1059 		struct ifreq ifr;
1060 		bool need_copyout;
1061 		if (copy_from_user(&ifr, argp, sizeof(struct ifreq)))
1062 			return -EFAULT;
1063 		err = dev_ioctl(net, cmd, &ifr, &need_copyout);
1064 		if (!err && need_copyout)
1065 			if (copy_to_user(argp, &ifr, sizeof(struct ifreq)))
1066 				return -EFAULT;
1067 	}
1068 	return err;
1069 }
1070 
1071 /*
1072  *	With an ioctl, arg may well be a user mode pointer, but we don't know
1073  *	what to do with it - that's up to the protocol still.
1074  */
1075 
1076 /**
1077  *	get_net_ns - increment the refcount of the network namespace
1078  *	@ns: common namespace (net)
1079  *
1080  *	Returns the net's common namespace.
1081  */
1082 
1083 struct ns_common *get_net_ns(struct ns_common *ns)
1084 {
1085 	return &get_net(container_of(ns, struct net, ns))->ns;
1086 }
1087 EXPORT_SYMBOL_GPL(get_net_ns);
1088 
1089 static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
1090 {
1091 	struct socket *sock;
1092 	struct sock *sk;
1093 	void __user *argp = (void __user *)arg;
1094 	int pid, err;
1095 	struct net *net;
1096 
1097 	sock = file->private_data;
1098 	sk = sock->sk;
1099 	net = sock_net(sk);
1100 	if (unlikely(cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))) {
1101 		struct ifreq ifr;
1102 		bool need_copyout;
1103 		if (copy_from_user(&ifr, argp, sizeof(struct ifreq)))
1104 			return -EFAULT;
1105 		err = dev_ioctl(net, cmd, &ifr, &need_copyout);
1106 		if (!err && need_copyout)
1107 			if (copy_to_user(argp, &ifr, sizeof(struct ifreq)))
1108 				return -EFAULT;
1109 	} else
1110 #ifdef CONFIG_WEXT_CORE
1111 	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
1112 		err = wext_handle_ioctl(net, cmd, argp);
1113 	} else
1114 #endif
1115 		switch (cmd) {
1116 		case FIOSETOWN:
1117 		case SIOCSPGRP:
1118 			err = -EFAULT;
1119 			if (get_user(pid, (int __user *)argp))
1120 				break;
1121 			err = f_setown(sock->file, pid, 1);
1122 			break;
1123 		case FIOGETOWN:
1124 		case SIOCGPGRP:
1125 			err = put_user(f_getown(sock->file),
1126 				       (int __user *)argp);
1127 			break;
1128 		case SIOCGIFBR:
1129 		case SIOCSIFBR:
1130 		case SIOCBRADDBR:
1131 		case SIOCBRDELBR:
1132 			err = -ENOPKG;
1133 			if (!br_ioctl_hook)
1134 				request_module("bridge");
1135 
1136 			mutex_lock(&br_ioctl_mutex);
1137 			if (br_ioctl_hook)
1138 				err = br_ioctl_hook(net, cmd, argp);
1139 			mutex_unlock(&br_ioctl_mutex);
1140 			break;
1141 		case SIOCGIFVLAN:
1142 		case SIOCSIFVLAN:
1143 			err = -ENOPKG;
1144 			if (!vlan_ioctl_hook)
1145 				request_module("8021q");
1146 
1147 			mutex_lock(&vlan_ioctl_mutex);
1148 			if (vlan_ioctl_hook)
1149 				err = vlan_ioctl_hook(net, argp);
1150 			mutex_unlock(&vlan_ioctl_mutex);
1151 			break;
1152 		case SIOCADDDLCI:
1153 		case SIOCDELDLCI:
1154 			err = -ENOPKG;
1155 			if (!dlci_ioctl_hook)
1156 				request_module("dlci");
1157 
1158 			mutex_lock(&dlci_ioctl_mutex);
1159 			if (dlci_ioctl_hook)
1160 				err = dlci_ioctl_hook(cmd, argp);
1161 			mutex_unlock(&dlci_ioctl_mutex);
1162 			break;
1163 		case SIOCGSKNS:
1164 			err = -EPERM;
1165 			if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1166 				break;
1167 
1168 			err = open_related_ns(&net->ns, get_net_ns);
1169 			break;
1170 		case SIOCGSTAMP_OLD:
1171 		case SIOCGSTAMPNS_OLD:
1172 			if (!sock->ops->gettstamp) {
1173 				err = -ENOIOCTLCMD;
1174 				break;
1175 			}
1176 			err = sock->ops->gettstamp(sock, argp,
1177 						   cmd == SIOCGSTAMP_OLD,
1178 						   !IS_ENABLED(CONFIG_64BIT));
1179 			break;
1180 		case SIOCGSTAMP_NEW:
1181 		case SIOCGSTAMPNS_NEW:
1182 			if (!sock->ops->gettstamp) {
1183 				err = -ENOIOCTLCMD;
1184 				break;
1185 			}
1186 			err = sock->ops->gettstamp(sock, argp,
1187 						   cmd == SIOCGSTAMP_NEW,
1188 						   false);
1189 			break;
1190 		default:
1191 			err = sock_do_ioctl(net, sock, cmd, arg);
1192 			break;
1193 		}
1194 	return err;
1195 }
1196 
1197 /**
1198  *	sock_create_lite - creates a socket
1199  *	@family: protocol family (AF_INET, ...)
1200  *	@type: communication type (SOCK_STREAM, ...)
1201  *	@protocol: protocol (0, ...)
1202  *	@res: new socket
1203  *
1204  *	Creates a new socket and assigns it to @res, passing through LSM.
1205  *	The new socket initialization is not complete, see kernel_accept().
1206  *	Returns 0 or an error. On failure @res is set to %NULL.
1207  *	This function internally uses GFP_KERNEL.
1208  */
1209 
1210 int sock_create_lite(int family, int type, int protocol, struct socket **res)
1211 {
1212 	int err;
1213 	struct socket *sock = NULL;
1214 
1215 	err = security_socket_create(family, type, protocol, 1);
1216 	if (err)
1217 		goto out;
1218 
1219 	sock = sock_alloc();
1220 	if (!sock) {
1221 		err = -ENOMEM;
1222 		goto out;
1223 	}
1224 
1225 	sock->type = type;
1226 	err = security_socket_post_create(sock, family, type, protocol, 1);
1227 	if (err)
1228 		goto out_release;
1229 
1230 out:
1231 	*res = sock;
1232 	return err;
1233 out_release:
1234 	sock_release(sock);
1235 	sock = NULL;
1236 	goto out;
1237 }
1238 EXPORT_SYMBOL(sock_create_lite);
1239 
1240 /* No kernel lock held - perfect */
1241 static __poll_t sock_poll(struct file *file, poll_table *wait)
1242 {
1243 	struct socket *sock = file->private_data;
1244 	__poll_t events = poll_requested_events(wait), flag = 0;
1245 
1246 	if (!sock->ops->poll)
1247 		return 0;
1248 
1249 	if (sk_can_busy_loop(sock->sk)) {
1250 		/* poll once if requested by the syscall */
1251 		if (events & POLL_BUSY_LOOP)
1252 			sk_busy_loop(sock->sk, 1);
1253 
1254 		/* if this socket can poll_ll, tell the system call */
1255 		flag = POLL_BUSY_LOOP;
1256 	}
1257 
1258 	return sock->ops->poll(file, sock, wait) | flag;
1259 }
1260 
1261 static int sock_mmap(struct file *file, struct vm_area_struct *vma)
1262 {
1263 	struct socket *sock = file->private_data;
1264 
1265 	return sock->ops->mmap(file, sock, vma);
1266 }
1267 
1268 static int sock_close(struct inode *inode, struct file *filp)
1269 {
1270 	__sock_release(SOCKET_I(inode), inode);
1271 	return 0;
1272 }
1273 
1274 /*
1275  *	Update the socket async list
1276  *
1277  *	Fasync_list locking strategy.
1278  *
1279  *	1. fasync_list is modified only under process context socket lock
1280  *	   i.e. under semaphore.
1281  *	2. fasync_list is used under read_lock(&sk->sk_callback_lock)
1282  *	   or under socket lock
1283  */
1284 
1285 static int sock_fasync(int fd, struct file *filp, int on)
1286 {
1287 	struct socket *sock = filp->private_data;
1288 	struct sock *sk = sock->sk;
1289 	struct socket_wq *wq = &sock->wq;
1290 
1291 	if (sk == NULL)
1292 		return -EINVAL;
1293 
1294 	lock_sock(sk);
1295 	fasync_helper(fd, filp, on, &wq->fasync_list);
1296 
1297 	if (!wq->fasync_list)
1298 		sock_reset_flag(sk, SOCK_FASYNC);
1299 	else
1300 		sock_set_flag(sk, SOCK_FASYNC);
1301 
1302 	release_sock(sk);
1303 	return 0;
1304 }
1305 
1306 /* This function may be called only under rcu_lock */
1307 
1308 int sock_wake_async(struct socket_wq *wq, int how, int band)
1309 {
1310 	if (!wq || !wq->fasync_list)
1311 		return -1;
1312 
1313 	switch (how) {
1314 	case SOCK_WAKE_WAITD:
1315 		if (test_bit(SOCKWQ_ASYNC_WAITDATA, &wq->flags))
1316 			break;
1317 		goto call_kill;
1318 	case SOCK_WAKE_SPACE:
1319 		if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags))
1320 			break;
1321 		/* fall through */
1322 	case SOCK_WAKE_IO:
1323 call_kill:
1324 		kill_fasync(&wq->fasync_list, SIGIO, band);
1325 		break;
1326 	case SOCK_WAKE_URG:
1327 		kill_fasync(&wq->fasync_list, SIGURG, band);
1328 	}
1329 
1330 	return 0;
1331 }
1332 EXPORT_SYMBOL(sock_wake_async);
1333 
1334 /**
1335  *	__sock_create - creates a socket
1336  *	@net: net namespace
1337  *	@family: protocol family (AF_INET, ...)
1338  *	@type: communication type (SOCK_STREAM, ...)
1339  *	@protocol: protocol (0, ...)
1340  *	@res: new socket
1341  *	@kern: boolean for kernel space sockets
1342  *
1343  *	Creates a new socket and assigns it to @res, passing through LSM.
1344  *	Returns 0 or an error. On failure @res is set to %NULL. @kern must
1345  *	be set to true if the socket resides in kernel space.
1346  *	This function internally uses GFP_KERNEL.
1347  */
1348 
1349 int __sock_create(struct net *net, int family, int type, int protocol,
1350 			 struct socket **res, int kern)
1351 {
1352 	int err;
1353 	struct socket *sock;
1354 	const struct net_proto_family *pf;
1355 
1356 	/*
1357 	 *      Check protocol is in range
1358 	 */
1359 	if (family < 0 || family >= NPROTO)
1360 		return -EAFNOSUPPORT;
1361 	if (type < 0 || type >= SOCK_MAX)
1362 		return -EINVAL;
1363 
1364 	/* Compatibility.
1365 
1366 	   This uglymoron is moved from INET layer to here to avoid
1367 	   deadlock in module load.
1368 	 */
1369 	if (family == PF_INET && type == SOCK_PACKET) {
1370 		pr_info_once("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
1371 			     current->comm);
1372 		family = PF_PACKET;
1373 	}
1374 
1375 	err = security_socket_create(family, type, protocol, kern);
1376 	if (err)
1377 		return err;
1378 
1379 	/*
1380 	 *	Allocate the socket and allow the family to set things up. if
1381 	 *	the protocol is 0, the family is instructed to select an appropriate
1382 	 *	default.
1383 	 */
1384 	sock = sock_alloc();
1385 	if (!sock) {
1386 		net_warn_ratelimited("socket: no more sockets\n");
1387 		return -ENFILE;	/* Not exactly a match, but its the
1388 				   closest posix thing */
1389 	}
1390 
1391 	sock->type = type;
1392 
1393 #ifdef CONFIG_MODULES
1394 	/* Attempt to load a protocol module if the find failed.
1395 	 *
1396 	 * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
1397 	 * requested real, full-featured networking support upon configuration.
1398 	 * Otherwise module support will break!
1399 	 */
1400 	if (rcu_access_pointer(net_families[family]) == NULL)
1401 		request_module("net-pf-%d", family);
1402 #endif
1403 
1404 	rcu_read_lock();
1405 	pf = rcu_dereference(net_families[family]);
1406 	err = -EAFNOSUPPORT;
1407 	if (!pf)
1408 		goto out_release;
1409 
1410 	/*
1411 	 * We will call the ->create function, that possibly is in a loadable
1412 	 * module, so we have to bump that loadable module refcnt first.
1413 	 */
1414 	if (!try_module_get(pf->owner))
1415 		goto out_release;
1416 
1417 	/* Now protected by module ref count */
1418 	rcu_read_unlock();
1419 
1420 	err = pf->create(net, sock, protocol, kern);
1421 	if (err < 0)
1422 		goto out_module_put;
1423 
1424 	/*
1425 	 * Now to bump the refcnt of the [loadable] module that owns this
1426 	 * socket at sock_release time we decrement its refcnt.
1427 	 */
1428 	if (!try_module_get(sock->ops->owner))
1429 		goto out_module_busy;
1430 
1431 	/*
1432 	 * Now that we're done with the ->create function, the [loadable]
1433 	 * module can have its refcnt decremented
1434 	 */
1435 	module_put(pf->owner);
1436 	err = security_socket_post_create(sock, family, type, protocol, kern);
1437 	if (err)
1438 		goto out_sock_release;
1439 	*res = sock;
1440 
1441 	return 0;
1442 
1443 out_module_busy:
1444 	err = -EAFNOSUPPORT;
1445 out_module_put:
1446 	sock->ops = NULL;
1447 	module_put(pf->owner);
1448 out_sock_release:
1449 	sock_release(sock);
1450 	return err;
1451 
1452 out_release:
1453 	rcu_read_unlock();
1454 	goto out_sock_release;
1455 }
1456 EXPORT_SYMBOL(__sock_create);
1457 
1458 /**
1459  *	sock_create - creates a socket
1460  *	@family: protocol family (AF_INET, ...)
1461  *	@type: communication type (SOCK_STREAM, ...)
1462  *	@protocol: protocol (0, ...)
1463  *	@res: new socket
1464  *
1465  *	A wrapper around __sock_create().
1466  *	Returns 0 or an error. This function internally uses GFP_KERNEL.
1467  */
1468 
1469 int sock_create(int family, int type, int protocol, struct socket **res)
1470 {
1471 	return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
1472 }
1473 EXPORT_SYMBOL(sock_create);
1474 
1475 /**
1476  *	sock_create_kern - creates a socket (kernel space)
1477  *	@net: net namespace
1478  *	@family: protocol family (AF_INET, ...)
1479  *	@type: communication type (SOCK_STREAM, ...)
1480  *	@protocol: protocol (0, ...)
1481  *	@res: new socket
1482  *
1483  *	A wrapper around __sock_create().
1484  *	Returns 0 or an error. This function internally uses GFP_KERNEL.
1485  */
1486 
1487 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
1488 {
1489 	return __sock_create(net, family, type, protocol, res, 1);
1490 }
1491 EXPORT_SYMBOL(sock_create_kern);
1492 
1493 int __sys_socket(int family, int type, int protocol)
1494 {
1495 	int retval;
1496 	struct socket *sock;
1497 	int flags;
1498 
1499 	/* Check the SOCK_* constants for consistency.  */
1500 	BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
1501 	BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
1502 	BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
1503 	BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
1504 
1505 	flags = type & ~SOCK_TYPE_MASK;
1506 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1507 		return -EINVAL;
1508 	type &= SOCK_TYPE_MASK;
1509 
1510 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1511 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1512 
1513 	retval = sock_create(family, type, protocol, &sock);
1514 	if (retval < 0)
1515 		return retval;
1516 
1517 	return sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
1518 }
1519 
1520 SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
1521 {
1522 	return __sys_socket(family, type, protocol);
1523 }
1524 
1525 /*
1526  *	Create a pair of connected sockets.
1527  */
1528 
1529 int __sys_socketpair(int family, int type, int protocol, int __user *usockvec)
1530 {
1531 	struct socket *sock1, *sock2;
1532 	int fd1, fd2, err;
1533 	struct file *newfile1, *newfile2;
1534 	int flags;
1535 
1536 	flags = type & ~SOCK_TYPE_MASK;
1537 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1538 		return -EINVAL;
1539 	type &= SOCK_TYPE_MASK;
1540 
1541 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1542 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1543 
1544 	/*
1545 	 * reserve descriptors and make sure we won't fail
1546 	 * to return them to userland.
1547 	 */
1548 	fd1 = get_unused_fd_flags(flags);
1549 	if (unlikely(fd1 < 0))
1550 		return fd1;
1551 
1552 	fd2 = get_unused_fd_flags(flags);
1553 	if (unlikely(fd2 < 0)) {
1554 		put_unused_fd(fd1);
1555 		return fd2;
1556 	}
1557 
1558 	err = put_user(fd1, &usockvec[0]);
1559 	if (err)
1560 		goto out;
1561 
1562 	err = put_user(fd2, &usockvec[1]);
1563 	if (err)
1564 		goto out;
1565 
1566 	/*
1567 	 * Obtain the first socket and check if the underlying protocol
1568 	 * supports the socketpair call.
1569 	 */
1570 
1571 	err = sock_create(family, type, protocol, &sock1);
1572 	if (unlikely(err < 0))
1573 		goto out;
1574 
1575 	err = sock_create(family, type, protocol, &sock2);
1576 	if (unlikely(err < 0)) {
1577 		sock_release(sock1);
1578 		goto out;
1579 	}
1580 
1581 	err = security_socket_socketpair(sock1, sock2);
1582 	if (unlikely(err)) {
1583 		sock_release(sock2);
1584 		sock_release(sock1);
1585 		goto out;
1586 	}
1587 
1588 	err = sock1->ops->socketpair(sock1, sock2);
1589 	if (unlikely(err < 0)) {
1590 		sock_release(sock2);
1591 		sock_release(sock1);
1592 		goto out;
1593 	}
1594 
1595 	newfile1 = sock_alloc_file(sock1, flags, NULL);
1596 	if (IS_ERR(newfile1)) {
1597 		err = PTR_ERR(newfile1);
1598 		sock_release(sock2);
1599 		goto out;
1600 	}
1601 
1602 	newfile2 = sock_alloc_file(sock2, flags, NULL);
1603 	if (IS_ERR(newfile2)) {
1604 		err = PTR_ERR(newfile2);
1605 		fput(newfile1);
1606 		goto out;
1607 	}
1608 
1609 	audit_fd_pair(fd1, fd2);
1610 
1611 	fd_install(fd1, newfile1);
1612 	fd_install(fd2, newfile2);
1613 	return 0;
1614 
1615 out:
1616 	put_unused_fd(fd2);
1617 	put_unused_fd(fd1);
1618 	return err;
1619 }
1620 
1621 SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
1622 		int __user *, usockvec)
1623 {
1624 	return __sys_socketpair(family, type, protocol, usockvec);
1625 }
1626 
1627 /*
1628  *	Bind a name to a socket. Nothing much to do here since it's
1629  *	the protocol's responsibility to handle the local address.
1630  *
1631  *	We move the socket address to kernel space before we call
1632  *	the protocol layer (having also checked the address is ok).
1633  */
1634 
1635 int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
1636 {
1637 	struct socket *sock;
1638 	struct sockaddr_storage address;
1639 	int err, fput_needed;
1640 
1641 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1642 	if (sock) {
1643 		err = move_addr_to_kernel(umyaddr, addrlen, &address);
1644 		if (!err) {
1645 			err = security_socket_bind(sock,
1646 						   (struct sockaddr *)&address,
1647 						   addrlen);
1648 			if (!err)
1649 				err = sock->ops->bind(sock,
1650 						      (struct sockaddr *)
1651 						      &address, addrlen);
1652 		}
1653 		fput_light(sock->file, fput_needed);
1654 	}
1655 	return err;
1656 }
1657 
1658 SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
1659 {
1660 	return __sys_bind(fd, umyaddr, addrlen);
1661 }
1662 
1663 /*
1664  *	Perform a listen. Basically, we allow the protocol to do anything
1665  *	necessary for a listen, and if that works, we mark the socket as
1666  *	ready for listening.
1667  */
1668 
1669 int __sys_listen(int fd, int backlog)
1670 {
1671 	struct socket *sock;
1672 	int err, fput_needed;
1673 	int somaxconn;
1674 
1675 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1676 	if (sock) {
1677 		somaxconn = sock_net(sock->sk)->core.sysctl_somaxconn;
1678 		if ((unsigned int)backlog > somaxconn)
1679 			backlog = somaxconn;
1680 
1681 		err = security_socket_listen(sock, backlog);
1682 		if (!err)
1683 			err = sock->ops->listen(sock, backlog);
1684 
1685 		fput_light(sock->file, fput_needed);
1686 	}
1687 	return err;
1688 }
1689 
1690 SYSCALL_DEFINE2(listen, int, fd, int, backlog)
1691 {
1692 	return __sys_listen(fd, backlog);
1693 }
1694 
1695 int __sys_accept4_file(struct file *file, unsigned file_flags,
1696 		       struct sockaddr __user *upeer_sockaddr,
1697 		       int __user *upeer_addrlen, int flags)
1698 {
1699 	struct socket *sock, *newsock;
1700 	struct file *newfile;
1701 	int err, len, newfd;
1702 	struct sockaddr_storage address;
1703 
1704 	if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1705 		return -EINVAL;
1706 
1707 	if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1708 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1709 
1710 	sock = sock_from_file(file, &err);
1711 	if (!sock)
1712 		goto out;
1713 
1714 	err = -ENFILE;
1715 	newsock = sock_alloc();
1716 	if (!newsock)
1717 		goto out;
1718 
1719 	newsock->type = sock->type;
1720 	newsock->ops = sock->ops;
1721 
1722 	/*
1723 	 * We don't need try_module_get here, as the listening socket (sock)
1724 	 * has the protocol module (sock->ops->owner) held.
1725 	 */
1726 	__module_get(newsock->ops->owner);
1727 
1728 	newfd = get_unused_fd_flags(flags);
1729 	if (unlikely(newfd < 0)) {
1730 		err = newfd;
1731 		sock_release(newsock);
1732 		goto out;
1733 	}
1734 	newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);
1735 	if (IS_ERR(newfile)) {
1736 		err = PTR_ERR(newfile);
1737 		put_unused_fd(newfd);
1738 		goto out;
1739 	}
1740 
1741 	err = security_socket_accept(sock, newsock);
1742 	if (err)
1743 		goto out_fd;
1744 
1745 	err = sock->ops->accept(sock, newsock, sock->file->f_flags | file_flags,
1746 					false);
1747 	if (err < 0)
1748 		goto out_fd;
1749 
1750 	if (upeer_sockaddr) {
1751 		len = newsock->ops->getname(newsock,
1752 					(struct sockaddr *)&address, 2);
1753 		if (len < 0) {
1754 			err = -ECONNABORTED;
1755 			goto out_fd;
1756 		}
1757 		err = move_addr_to_user(&address,
1758 					len, upeer_sockaddr, upeer_addrlen);
1759 		if (err < 0)
1760 			goto out_fd;
1761 	}
1762 
1763 	/* File flags are not inherited via accept() unlike another OSes. */
1764 
1765 	fd_install(newfd, newfile);
1766 	err = newfd;
1767 out:
1768 	return err;
1769 out_fd:
1770 	fput(newfile);
1771 	put_unused_fd(newfd);
1772 	goto out;
1773 
1774 }
1775 
1776 /*
1777  *	For accept, we attempt to create a new socket, set up the link
1778  *	with the client, wake up the client, then return the new
1779  *	connected fd. We collect the address of the connector in kernel
1780  *	space and move it to user at the very end. This is unclean because
1781  *	we open the socket then return an error.
1782  *
1783  *	1003.1g adds the ability to recvmsg() to query connection pending
1784  *	status to recvmsg. We need to add that support in a way thats
1785  *	clean when we restructure accept also.
1786  */
1787 
1788 int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
1789 		  int __user *upeer_addrlen, int flags)
1790 {
1791 	int ret = -EBADF;
1792 	struct fd f;
1793 
1794 	f = fdget(fd);
1795 	if (f.file) {
1796 		ret = __sys_accept4_file(f.file, 0, upeer_sockaddr,
1797 						upeer_addrlen, flags);
1798 		if (f.flags)
1799 			fput(f.file);
1800 	}
1801 
1802 	return ret;
1803 }
1804 
1805 SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
1806 		int __user *, upeer_addrlen, int, flags)
1807 {
1808 	return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, flags);
1809 }
1810 
1811 SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
1812 		int __user *, upeer_addrlen)
1813 {
1814 	return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
1815 }
1816 
1817 /*
1818  *	Attempt to connect to a socket with the server address.  The address
1819  *	is in user space so we verify it is OK and move it to kernel space.
1820  *
1821  *	For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
1822  *	break bindings
1823  *
1824  *	NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
1825  *	other SEQPACKET protocols that take time to connect() as it doesn't
1826  *	include the -EINPROGRESS status for such sockets.
1827  */
1828 
1829 int __sys_connect_file(struct file *file, struct sockaddr_storage *address,
1830 		       int addrlen, int file_flags)
1831 {
1832 	struct socket *sock;
1833 	int err;
1834 
1835 	sock = sock_from_file(file, &err);
1836 	if (!sock)
1837 		goto out;
1838 
1839 	err =
1840 	    security_socket_connect(sock, (struct sockaddr *)address, addrlen);
1841 	if (err)
1842 		goto out;
1843 
1844 	err = sock->ops->connect(sock, (struct sockaddr *)address, addrlen,
1845 				 sock->file->f_flags | file_flags);
1846 out:
1847 	return err;
1848 }
1849 
1850 int __sys_connect(int fd, struct sockaddr __user *uservaddr, int addrlen)
1851 {
1852 	int ret = -EBADF;
1853 	struct fd f;
1854 
1855 	f = fdget(fd);
1856 	if (f.file) {
1857 		struct sockaddr_storage address;
1858 
1859 		ret = move_addr_to_kernel(uservaddr, addrlen, &address);
1860 		if (!ret)
1861 			ret = __sys_connect_file(f.file, &address, addrlen, 0);
1862 		if (f.flags)
1863 			fput(f.file);
1864 	}
1865 
1866 	return ret;
1867 }
1868 
1869 SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
1870 		int, addrlen)
1871 {
1872 	return __sys_connect(fd, uservaddr, addrlen);
1873 }
1874 
1875 /*
1876  *	Get the local address ('name') of a socket object. Move the obtained
1877  *	name to user space.
1878  */
1879 
1880 int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
1881 		      int __user *usockaddr_len)
1882 {
1883 	struct socket *sock;
1884 	struct sockaddr_storage address;
1885 	int err, fput_needed;
1886 
1887 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1888 	if (!sock)
1889 		goto out;
1890 
1891 	err = security_socket_getsockname(sock);
1892 	if (err)
1893 		goto out_put;
1894 
1895 	err = sock->ops->getname(sock, (struct sockaddr *)&address, 0);
1896 	if (err < 0)
1897 		goto out_put;
1898         /* "err" is actually length in this case */
1899 	err = move_addr_to_user(&address, err, usockaddr, usockaddr_len);
1900 
1901 out_put:
1902 	fput_light(sock->file, fput_needed);
1903 out:
1904 	return err;
1905 }
1906 
1907 SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
1908 		int __user *, usockaddr_len)
1909 {
1910 	return __sys_getsockname(fd, usockaddr, usockaddr_len);
1911 }
1912 
1913 /*
1914  *	Get the remote address ('name') of a socket object. Move the obtained
1915  *	name to user space.
1916  */
1917 
1918 int __sys_getpeername(int fd, struct sockaddr __user *usockaddr,
1919 		      int __user *usockaddr_len)
1920 {
1921 	struct socket *sock;
1922 	struct sockaddr_storage address;
1923 	int err, fput_needed;
1924 
1925 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1926 	if (sock != NULL) {
1927 		err = security_socket_getpeername(sock);
1928 		if (err) {
1929 			fput_light(sock->file, fput_needed);
1930 			return err;
1931 		}
1932 
1933 		err = sock->ops->getname(sock, (struct sockaddr *)&address, 1);
1934 		if (err >= 0)
1935 			/* "err" is actually length in this case */
1936 			err = move_addr_to_user(&address, err, usockaddr,
1937 						usockaddr_len);
1938 		fput_light(sock->file, fput_needed);
1939 	}
1940 	return err;
1941 }
1942 
1943 SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
1944 		int __user *, usockaddr_len)
1945 {
1946 	return __sys_getpeername(fd, usockaddr, usockaddr_len);
1947 }
1948 
1949 /*
1950  *	Send a datagram to a given address. We move the address into kernel
1951  *	space and check the user space data area is readable before invoking
1952  *	the protocol.
1953  */
1954 int __sys_sendto(int fd, void __user *buff, size_t len, unsigned int flags,
1955 		 struct sockaddr __user *addr,  int addr_len)
1956 {
1957 	struct socket *sock;
1958 	struct sockaddr_storage address;
1959 	int err;
1960 	struct msghdr msg;
1961 	struct iovec iov;
1962 	int fput_needed;
1963 
1964 	err = import_single_range(WRITE, buff, len, &iov, &msg.msg_iter);
1965 	if (unlikely(err))
1966 		return err;
1967 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1968 	if (!sock)
1969 		goto out;
1970 
1971 	msg.msg_name = NULL;
1972 	msg.msg_control = NULL;
1973 	msg.msg_controllen = 0;
1974 	msg.msg_namelen = 0;
1975 	if (addr) {
1976 		err = move_addr_to_kernel(addr, addr_len, &address);
1977 		if (err < 0)
1978 			goto out_put;
1979 		msg.msg_name = (struct sockaddr *)&address;
1980 		msg.msg_namelen = addr_len;
1981 	}
1982 	if (sock->file->f_flags & O_NONBLOCK)
1983 		flags |= MSG_DONTWAIT;
1984 	msg.msg_flags = flags;
1985 	err = sock_sendmsg(sock, &msg);
1986 
1987 out_put:
1988 	fput_light(sock->file, fput_needed);
1989 out:
1990 	return err;
1991 }
1992 
1993 SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
1994 		unsigned int, flags, struct sockaddr __user *, addr,
1995 		int, addr_len)
1996 {
1997 	return __sys_sendto(fd, buff, len, flags, addr, addr_len);
1998 }
1999 
2000 /*
2001  *	Send a datagram down a socket.
2002  */
2003 
2004 SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
2005 		unsigned int, flags)
2006 {
2007 	return __sys_sendto(fd, buff, len, flags, NULL, 0);
2008 }
2009 
2010 /*
2011  *	Receive a frame from the socket and optionally record the address of the
2012  *	sender. We verify the buffers are writable and if needed move the
2013  *	sender address from kernel to user space.
2014  */
2015 int __sys_recvfrom(int fd, void __user *ubuf, size_t size, unsigned int flags,
2016 		   struct sockaddr __user *addr, int __user *addr_len)
2017 {
2018 	struct socket *sock;
2019 	struct iovec iov;
2020 	struct msghdr msg;
2021 	struct sockaddr_storage address;
2022 	int err, err2;
2023 	int fput_needed;
2024 
2025 	err = import_single_range(READ, ubuf, size, &iov, &msg.msg_iter);
2026 	if (unlikely(err))
2027 		return err;
2028 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2029 	if (!sock)
2030 		goto out;
2031 
2032 	msg.msg_control = NULL;
2033 	msg.msg_controllen = 0;
2034 	/* Save some cycles and don't copy the address if not needed */
2035 	msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
2036 	/* We assume all kernel code knows the size of sockaddr_storage */
2037 	msg.msg_namelen = 0;
2038 	msg.msg_iocb = NULL;
2039 	msg.msg_flags = 0;
2040 	if (sock->file->f_flags & O_NONBLOCK)
2041 		flags |= MSG_DONTWAIT;
2042 	err = sock_recvmsg(sock, &msg, flags);
2043 
2044 	if (err >= 0 && addr != NULL) {
2045 		err2 = move_addr_to_user(&address,
2046 					 msg.msg_namelen, addr, addr_len);
2047 		if (err2 < 0)
2048 			err = err2;
2049 	}
2050 
2051 	fput_light(sock->file, fput_needed);
2052 out:
2053 	return err;
2054 }
2055 
2056 SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
2057 		unsigned int, flags, struct sockaddr __user *, addr,
2058 		int __user *, addr_len)
2059 {
2060 	return __sys_recvfrom(fd, ubuf, size, flags, addr, addr_len);
2061 }
2062 
2063 /*
2064  *	Receive a datagram from a socket.
2065  */
2066 
2067 SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
2068 		unsigned int, flags)
2069 {
2070 	return __sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
2071 }
2072 
2073 /*
2074  *	Set a socket option. Because we don't know the option lengths we have
2075  *	to pass the user mode parameter for the protocols to sort out.
2076  */
2077 
2078 static int __sys_setsockopt(int fd, int level, int optname,
2079 			    char __user *optval, int optlen)
2080 {
2081 	mm_segment_t oldfs = get_fs();
2082 	char *kernel_optval = NULL;
2083 	int err, fput_needed;
2084 	struct socket *sock;
2085 
2086 	if (optlen < 0)
2087 		return -EINVAL;
2088 
2089 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2090 	if (sock != NULL) {
2091 		err = security_socket_setsockopt(sock, level, optname);
2092 		if (err)
2093 			goto out_put;
2094 
2095 		err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level,
2096 						     &optname, optval, &optlen,
2097 						     &kernel_optval);
2098 
2099 		if (err < 0) {
2100 			goto out_put;
2101 		} else if (err > 0) {
2102 			err = 0;
2103 			goto out_put;
2104 		}
2105 
2106 		if (kernel_optval) {
2107 			set_fs(KERNEL_DS);
2108 			optval = (char __user __force *)kernel_optval;
2109 		}
2110 
2111 		if (level == SOL_SOCKET)
2112 			err =
2113 			    sock_setsockopt(sock, level, optname, optval,
2114 					    optlen);
2115 		else
2116 			err =
2117 			    sock->ops->setsockopt(sock, level, optname, optval,
2118 						  optlen);
2119 
2120 		if (kernel_optval) {
2121 			set_fs(oldfs);
2122 			kfree(kernel_optval);
2123 		}
2124 out_put:
2125 		fput_light(sock->file, fput_needed);
2126 	}
2127 	return err;
2128 }
2129 
2130 SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
2131 		char __user *, optval, int, optlen)
2132 {
2133 	return __sys_setsockopt(fd, level, optname, optval, optlen);
2134 }
2135 
2136 /*
2137  *	Get a socket option. Because we don't know the option lengths we have
2138  *	to pass a user mode parameter for the protocols to sort out.
2139  */
2140 
2141 static int __sys_getsockopt(int fd, int level, int optname,
2142 			    char __user *optval, int __user *optlen)
2143 {
2144 	int err, fput_needed;
2145 	struct socket *sock;
2146 	int max_optlen;
2147 
2148 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2149 	if (sock != NULL) {
2150 		err = security_socket_getsockopt(sock, level, optname);
2151 		if (err)
2152 			goto out_put;
2153 
2154 		max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
2155 
2156 		if (level == SOL_SOCKET)
2157 			err =
2158 			    sock_getsockopt(sock, level, optname, optval,
2159 					    optlen);
2160 		else
2161 			err =
2162 			    sock->ops->getsockopt(sock, level, optname, optval,
2163 						  optlen);
2164 
2165 		err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
2166 						     optval, optlen,
2167 						     max_optlen, err);
2168 out_put:
2169 		fput_light(sock->file, fput_needed);
2170 	}
2171 	return err;
2172 }
2173 
2174 SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
2175 		char __user *, optval, int __user *, optlen)
2176 {
2177 	return __sys_getsockopt(fd, level, optname, optval, optlen);
2178 }
2179 
2180 /*
2181  *	Shutdown a socket.
2182  */
2183 
2184 int __sys_shutdown(int fd, int how)
2185 {
2186 	int err, fput_needed;
2187 	struct socket *sock;
2188 
2189 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2190 	if (sock != NULL) {
2191 		err = security_socket_shutdown(sock, how);
2192 		if (!err)
2193 			err = sock->ops->shutdown(sock, how);
2194 		fput_light(sock->file, fput_needed);
2195 	}
2196 	return err;
2197 }
2198 
2199 SYSCALL_DEFINE2(shutdown, int, fd, int, how)
2200 {
2201 	return __sys_shutdown(fd, how);
2202 }
2203 
2204 /* A couple of helpful macros for getting the address of the 32/64 bit
2205  * fields which are the same type (int / unsigned) on our platforms.
2206  */
2207 #define COMPAT_MSG(msg, member)	((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
2208 #define COMPAT_NAMELEN(msg)	COMPAT_MSG(msg, msg_namelen)
2209 #define COMPAT_FLAGS(msg)	COMPAT_MSG(msg, msg_flags)
2210 
2211 struct used_address {
2212 	struct sockaddr_storage name;
2213 	unsigned int name_len;
2214 };
2215 
2216 static int copy_msghdr_from_user(struct msghdr *kmsg,
2217 				 struct user_msghdr __user *umsg,
2218 				 struct sockaddr __user **save_addr,
2219 				 struct iovec **iov)
2220 {
2221 	struct user_msghdr msg;
2222 	ssize_t err;
2223 
2224 	if (copy_from_user(&msg, umsg, sizeof(*umsg)))
2225 		return -EFAULT;
2226 
2227 	kmsg->msg_control = (void __force *)msg.msg_control;
2228 	kmsg->msg_controllen = msg.msg_controllen;
2229 	kmsg->msg_flags = msg.msg_flags;
2230 
2231 	kmsg->msg_namelen = msg.msg_namelen;
2232 	if (!msg.msg_name)
2233 		kmsg->msg_namelen = 0;
2234 
2235 	if (kmsg->msg_namelen < 0)
2236 		return -EINVAL;
2237 
2238 	if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
2239 		kmsg->msg_namelen = sizeof(struct sockaddr_storage);
2240 
2241 	if (save_addr)
2242 		*save_addr = msg.msg_name;
2243 
2244 	if (msg.msg_name && kmsg->msg_namelen) {
2245 		if (!save_addr) {
2246 			err = move_addr_to_kernel(msg.msg_name,
2247 						  kmsg->msg_namelen,
2248 						  kmsg->msg_name);
2249 			if (err < 0)
2250 				return err;
2251 		}
2252 	} else {
2253 		kmsg->msg_name = NULL;
2254 		kmsg->msg_namelen = 0;
2255 	}
2256 
2257 	if (msg.msg_iovlen > UIO_MAXIOV)
2258 		return -EMSGSIZE;
2259 
2260 	kmsg->msg_iocb = NULL;
2261 
2262 	err = import_iovec(save_addr ? READ : WRITE,
2263 			    msg.msg_iov, msg.msg_iovlen,
2264 			    UIO_FASTIOV, iov, &kmsg->msg_iter);
2265 	return err < 0 ? err : 0;
2266 }
2267 
2268 static int ____sys_sendmsg(struct socket *sock, struct msghdr *msg_sys,
2269 			   unsigned int flags, struct used_address *used_address,
2270 			   unsigned int allowed_msghdr_flags)
2271 {
2272 	unsigned char ctl[sizeof(struct cmsghdr) + 20]
2273 				__aligned(sizeof(__kernel_size_t));
2274 	/* 20 is size of ipv6_pktinfo */
2275 	unsigned char *ctl_buf = ctl;
2276 	int ctl_len;
2277 	ssize_t err;
2278 
2279 	err = -ENOBUFS;
2280 
2281 	if (msg_sys->msg_controllen > INT_MAX)
2282 		goto out;
2283 	flags |= (msg_sys->msg_flags & allowed_msghdr_flags);
2284 	ctl_len = msg_sys->msg_controllen;
2285 	if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
2286 		err =
2287 		    cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl,
2288 						     sizeof(ctl));
2289 		if (err)
2290 			goto out;
2291 		ctl_buf = msg_sys->msg_control;
2292 		ctl_len = msg_sys->msg_controllen;
2293 	} else if (ctl_len) {
2294 		BUILD_BUG_ON(sizeof(struct cmsghdr) !=
2295 			     CMSG_ALIGN(sizeof(struct cmsghdr)));
2296 		if (ctl_len > sizeof(ctl)) {
2297 			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
2298 			if (ctl_buf == NULL)
2299 				goto out;
2300 		}
2301 		err = -EFAULT;
2302 		/*
2303 		 * Careful! Before this, msg_sys->msg_control contains a user pointer.
2304 		 * Afterwards, it will be a kernel pointer. Thus the compiler-assisted
2305 		 * checking falls down on this.
2306 		 */
2307 		if (copy_from_user(ctl_buf,
2308 				   (void __user __force *)msg_sys->msg_control,
2309 				   ctl_len))
2310 			goto out_freectl;
2311 		msg_sys->msg_control = ctl_buf;
2312 	}
2313 	msg_sys->msg_flags = flags;
2314 
2315 	if (sock->file->f_flags & O_NONBLOCK)
2316 		msg_sys->msg_flags |= MSG_DONTWAIT;
2317 	/*
2318 	 * If this is sendmmsg() and current destination address is same as
2319 	 * previously succeeded address, omit asking LSM's decision.
2320 	 * used_address->name_len is initialized to UINT_MAX so that the first
2321 	 * destination address never matches.
2322 	 */
2323 	if (used_address && msg_sys->msg_name &&
2324 	    used_address->name_len == msg_sys->msg_namelen &&
2325 	    !memcmp(&used_address->name, msg_sys->msg_name,
2326 		    used_address->name_len)) {
2327 		err = sock_sendmsg_nosec(sock, msg_sys);
2328 		goto out_freectl;
2329 	}
2330 	err = sock_sendmsg(sock, msg_sys);
2331 	/*
2332 	 * If this is sendmmsg() and sending to current destination address was
2333 	 * successful, remember it.
2334 	 */
2335 	if (used_address && err >= 0) {
2336 		used_address->name_len = msg_sys->msg_namelen;
2337 		if (msg_sys->msg_name)
2338 			memcpy(&used_address->name, msg_sys->msg_name,
2339 			       used_address->name_len);
2340 	}
2341 
2342 out_freectl:
2343 	if (ctl_buf != ctl)
2344 		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
2345 out:
2346 	return err;
2347 }
2348 
2349 int sendmsg_copy_msghdr(struct msghdr *msg,
2350 			struct user_msghdr __user *umsg, unsigned flags,
2351 			struct iovec **iov)
2352 {
2353 	int err;
2354 
2355 	if (flags & MSG_CMSG_COMPAT) {
2356 		struct compat_msghdr __user *msg_compat;
2357 
2358 		msg_compat = (struct compat_msghdr __user *) umsg;
2359 		err = get_compat_msghdr(msg, msg_compat, NULL, iov);
2360 	} else {
2361 		err = copy_msghdr_from_user(msg, umsg, NULL, iov);
2362 	}
2363 	if (err < 0)
2364 		return err;
2365 
2366 	return 0;
2367 }
2368 
2369 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
2370 			 struct msghdr *msg_sys, unsigned int flags,
2371 			 struct used_address *used_address,
2372 			 unsigned int allowed_msghdr_flags)
2373 {
2374 	struct sockaddr_storage address;
2375 	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
2376 	ssize_t err;
2377 
2378 	msg_sys->msg_name = &address;
2379 
2380 	err = sendmsg_copy_msghdr(msg_sys, msg, flags, &iov);
2381 	if (err < 0)
2382 		return err;
2383 
2384 	err = ____sys_sendmsg(sock, msg_sys, flags, used_address,
2385 				allowed_msghdr_flags);
2386 	kfree(iov);
2387 	return err;
2388 }
2389 
2390 /*
2391  *	BSD sendmsg interface
2392  */
2393 long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,
2394 			unsigned int flags)
2395 {
2396 	/* disallow ancillary data requests from this path */
2397 	if (msg->msg_control || msg->msg_controllen)
2398 		return -EINVAL;
2399 
2400 	return ____sys_sendmsg(sock, msg, flags, NULL, 0);
2401 }
2402 
2403 long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2404 		   bool forbid_cmsg_compat)
2405 {
2406 	int fput_needed, err;
2407 	struct msghdr msg_sys;
2408 	struct socket *sock;
2409 
2410 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2411 		return -EINVAL;
2412 
2413 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2414 	if (!sock)
2415 		goto out;
2416 
2417 	err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL, 0);
2418 
2419 	fput_light(sock->file, fput_needed);
2420 out:
2421 	return err;
2422 }
2423 
2424 SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
2425 {
2426 	return __sys_sendmsg(fd, msg, flags, true);
2427 }
2428 
2429 /*
2430  *	Linux sendmmsg interface
2431  */
2432 
2433 int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2434 		   unsigned int flags, bool forbid_cmsg_compat)
2435 {
2436 	int fput_needed, err, datagrams;
2437 	struct socket *sock;
2438 	struct mmsghdr __user *entry;
2439 	struct compat_mmsghdr __user *compat_entry;
2440 	struct msghdr msg_sys;
2441 	struct used_address used_address;
2442 	unsigned int oflags = flags;
2443 
2444 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2445 		return -EINVAL;
2446 
2447 	if (vlen > UIO_MAXIOV)
2448 		vlen = UIO_MAXIOV;
2449 
2450 	datagrams = 0;
2451 
2452 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2453 	if (!sock)
2454 		return err;
2455 
2456 	used_address.name_len = UINT_MAX;
2457 	entry = mmsg;
2458 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2459 	err = 0;
2460 	flags |= MSG_BATCH;
2461 
2462 	while (datagrams < vlen) {
2463 		if (datagrams == vlen - 1)
2464 			flags = oflags;
2465 
2466 		if (MSG_CMSG_COMPAT & flags) {
2467 			err = ___sys_sendmsg(sock, (struct user_msghdr __user *)compat_entry,
2468 					     &msg_sys, flags, &used_address, MSG_EOR);
2469 			if (err < 0)
2470 				break;
2471 			err = __put_user(err, &compat_entry->msg_len);
2472 			++compat_entry;
2473 		} else {
2474 			err = ___sys_sendmsg(sock,
2475 					     (struct user_msghdr __user *)entry,
2476 					     &msg_sys, flags, &used_address, MSG_EOR);
2477 			if (err < 0)
2478 				break;
2479 			err = put_user(err, &entry->msg_len);
2480 			++entry;
2481 		}
2482 
2483 		if (err)
2484 			break;
2485 		++datagrams;
2486 		if (msg_data_left(&msg_sys))
2487 			break;
2488 		cond_resched();
2489 	}
2490 
2491 	fput_light(sock->file, fput_needed);
2492 
2493 	/* We only return an error if no datagrams were able to be sent */
2494 	if (datagrams != 0)
2495 		return datagrams;
2496 
2497 	return err;
2498 }
2499 
2500 SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
2501 		unsigned int, vlen, unsigned int, flags)
2502 {
2503 	return __sys_sendmmsg(fd, mmsg, vlen, flags, true);
2504 }
2505 
2506 int recvmsg_copy_msghdr(struct msghdr *msg,
2507 			struct user_msghdr __user *umsg, unsigned flags,
2508 			struct sockaddr __user **uaddr,
2509 			struct iovec **iov)
2510 {
2511 	ssize_t err;
2512 
2513 	if (MSG_CMSG_COMPAT & flags) {
2514 		struct compat_msghdr __user *msg_compat;
2515 
2516 		msg_compat = (struct compat_msghdr __user *) umsg;
2517 		err = get_compat_msghdr(msg, msg_compat, uaddr, iov);
2518 	} else {
2519 		err = copy_msghdr_from_user(msg, umsg, uaddr, iov);
2520 	}
2521 	if (err < 0)
2522 		return err;
2523 
2524 	return 0;
2525 }
2526 
2527 static int ____sys_recvmsg(struct socket *sock, struct msghdr *msg_sys,
2528 			   struct user_msghdr __user *msg,
2529 			   struct sockaddr __user *uaddr,
2530 			   unsigned int flags, int nosec)
2531 {
2532 	struct compat_msghdr __user *msg_compat =
2533 					(struct compat_msghdr __user *) msg;
2534 	int __user *uaddr_len = COMPAT_NAMELEN(msg);
2535 	struct sockaddr_storage addr;
2536 	unsigned long cmsg_ptr;
2537 	int len;
2538 	ssize_t err;
2539 
2540 	msg_sys->msg_name = &addr;
2541 	cmsg_ptr = (unsigned long)msg_sys->msg_control;
2542 	msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
2543 
2544 	/* We assume all kernel code knows the size of sockaddr_storage */
2545 	msg_sys->msg_namelen = 0;
2546 
2547 	if (sock->file->f_flags & O_NONBLOCK)
2548 		flags |= MSG_DONTWAIT;
2549 
2550 	if (unlikely(nosec))
2551 		err = sock_recvmsg_nosec(sock, msg_sys, flags);
2552 	else
2553 		err = sock_recvmsg(sock, msg_sys, flags);
2554 
2555 	if (err < 0)
2556 		goto out;
2557 	len = err;
2558 
2559 	if (uaddr != NULL) {
2560 		err = move_addr_to_user(&addr,
2561 					msg_sys->msg_namelen, uaddr,
2562 					uaddr_len);
2563 		if (err < 0)
2564 			goto out;
2565 	}
2566 	err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
2567 			 COMPAT_FLAGS(msg));
2568 	if (err)
2569 		goto out;
2570 	if (MSG_CMSG_COMPAT & flags)
2571 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2572 				 &msg_compat->msg_controllen);
2573 	else
2574 		err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2575 				 &msg->msg_controllen);
2576 	if (err)
2577 		goto out;
2578 	err = len;
2579 out:
2580 	return err;
2581 }
2582 
2583 static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
2584 			 struct msghdr *msg_sys, unsigned int flags, int nosec)
2585 {
2586 	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
2587 	/* user mode address pointers */
2588 	struct sockaddr __user *uaddr;
2589 	ssize_t err;
2590 
2591 	err = recvmsg_copy_msghdr(msg_sys, msg, flags, &uaddr, &iov);
2592 	if (err < 0)
2593 		return err;
2594 
2595 	err = ____sys_recvmsg(sock, msg_sys, msg, uaddr, flags, nosec);
2596 	kfree(iov);
2597 	return err;
2598 }
2599 
2600 /*
2601  *	BSD recvmsg interface
2602  */
2603 
2604 long __sys_recvmsg_sock(struct socket *sock, struct msghdr *msg,
2605 			struct user_msghdr __user *umsg,
2606 			struct sockaddr __user *uaddr, unsigned int flags)
2607 {
2608 	/* disallow ancillary data requests from this path */
2609 	if (msg->msg_control || msg->msg_controllen)
2610 		return -EINVAL;
2611 
2612 	return ____sys_recvmsg(sock, msg, umsg, uaddr, flags, 0);
2613 }
2614 
2615 long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2616 		   bool forbid_cmsg_compat)
2617 {
2618 	int fput_needed, err;
2619 	struct msghdr msg_sys;
2620 	struct socket *sock;
2621 
2622 	if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2623 		return -EINVAL;
2624 
2625 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2626 	if (!sock)
2627 		goto out;
2628 
2629 	err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
2630 
2631 	fput_light(sock->file, fput_needed);
2632 out:
2633 	return err;
2634 }
2635 
2636 SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
2637 		unsigned int, flags)
2638 {
2639 	return __sys_recvmsg(fd, msg, flags, true);
2640 }
2641 
2642 /*
2643  *     Linux recvmmsg interface
2644  */
2645 
2646 static int do_recvmmsg(int fd, struct mmsghdr __user *mmsg,
2647 			  unsigned int vlen, unsigned int flags,
2648 			  struct timespec64 *timeout)
2649 {
2650 	int fput_needed, err, datagrams;
2651 	struct socket *sock;
2652 	struct mmsghdr __user *entry;
2653 	struct compat_mmsghdr __user *compat_entry;
2654 	struct msghdr msg_sys;
2655 	struct timespec64 end_time;
2656 	struct timespec64 timeout64;
2657 
2658 	if (timeout &&
2659 	    poll_select_set_timeout(&end_time, timeout->tv_sec,
2660 				    timeout->tv_nsec))
2661 		return -EINVAL;
2662 
2663 	datagrams = 0;
2664 
2665 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
2666 	if (!sock)
2667 		return err;
2668 
2669 	if (likely(!(flags & MSG_ERRQUEUE))) {
2670 		err = sock_error(sock->sk);
2671 		if (err) {
2672 			datagrams = err;
2673 			goto out_put;
2674 		}
2675 	}
2676 
2677 	entry = mmsg;
2678 	compat_entry = (struct compat_mmsghdr __user *)mmsg;
2679 
2680 	while (datagrams < vlen) {
2681 		/*
2682 		 * No need to ask LSM for more than the first datagram.
2683 		 */
2684 		if (MSG_CMSG_COMPAT & flags) {
2685 			err = ___sys_recvmsg(sock, (struct user_msghdr __user *)compat_entry,
2686 					     &msg_sys, flags & ~MSG_WAITFORONE,
2687 					     datagrams);
2688 			if (err < 0)
2689 				break;
2690 			err = __put_user(err, &compat_entry->msg_len);
2691 			++compat_entry;
2692 		} else {
2693 			err = ___sys_recvmsg(sock,
2694 					     (struct user_msghdr __user *)entry,
2695 					     &msg_sys, flags & ~MSG_WAITFORONE,
2696 					     datagrams);
2697 			if (err < 0)
2698 				break;
2699 			err = put_user(err, &entry->msg_len);
2700 			++entry;
2701 		}
2702 
2703 		if (err)
2704 			break;
2705 		++datagrams;
2706 
2707 		/* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */
2708 		if (flags & MSG_WAITFORONE)
2709 			flags |= MSG_DONTWAIT;
2710 
2711 		if (timeout) {
2712 			ktime_get_ts64(&timeout64);
2713 			*timeout = timespec64_sub(end_time, timeout64);
2714 			if (timeout->tv_sec < 0) {
2715 				timeout->tv_sec = timeout->tv_nsec = 0;
2716 				break;
2717 			}
2718 
2719 			/* Timeout, return less than vlen datagrams */
2720 			if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
2721 				break;
2722 		}
2723 
2724 		/* Out of band data, return right away */
2725 		if (msg_sys.msg_flags & MSG_OOB)
2726 			break;
2727 		cond_resched();
2728 	}
2729 
2730 	if (err == 0)
2731 		goto out_put;
2732 
2733 	if (datagrams == 0) {
2734 		datagrams = err;
2735 		goto out_put;
2736 	}
2737 
2738 	/*
2739 	 * We may return less entries than requested (vlen) if the
2740 	 * sock is non block and there aren't enough datagrams...
2741 	 */
2742 	if (err != -EAGAIN) {
2743 		/*
2744 		 * ... or  if recvmsg returns an error after we
2745 		 * received some datagrams, where we record the
2746 		 * error to return on the next call or if the
2747 		 * app asks about it using getsockopt(SO_ERROR).
2748 		 */
2749 		sock->sk->sk_err = -err;
2750 	}
2751 out_put:
2752 	fput_light(sock->file, fput_needed);
2753 
2754 	return datagrams;
2755 }
2756 
2757 int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
2758 		   unsigned int vlen, unsigned int flags,
2759 		   struct __kernel_timespec __user *timeout,
2760 		   struct old_timespec32 __user *timeout32)
2761 {
2762 	int datagrams;
2763 	struct timespec64 timeout_sys;
2764 
2765 	if (timeout && get_timespec64(&timeout_sys, timeout))
2766 		return -EFAULT;
2767 
2768 	if (timeout32 && get_old_timespec32(&timeout_sys, timeout32))
2769 		return -EFAULT;
2770 
2771 	if (!timeout && !timeout32)
2772 		return do_recvmmsg(fd, mmsg, vlen, flags, NULL);
2773 
2774 	datagrams = do_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
2775 
2776 	if (datagrams <= 0)
2777 		return datagrams;
2778 
2779 	if (timeout && put_timespec64(&timeout_sys, timeout))
2780 		datagrams = -EFAULT;
2781 
2782 	if (timeout32 && put_old_timespec32(&timeout_sys, timeout32))
2783 		datagrams = -EFAULT;
2784 
2785 	return datagrams;
2786 }
2787 
2788 SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
2789 		unsigned int, vlen, unsigned int, flags,
2790 		struct __kernel_timespec __user *, timeout)
2791 {
2792 	if (flags & MSG_CMSG_COMPAT)
2793 		return -EINVAL;
2794 
2795 	return __sys_recvmmsg(fd, mmsg, vlen, flags, timeout, NULL);
2796 }
2797 
2798 #ifdef CONFIG_COMPAT_32BIT_TIME
2799 SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct mmsghdr __user *, mmsg,
2800 		unsigned int, vlen, unsigned int, flags,
2801 		struct old_timespec32 __user *, timeout)
2802 {
2803 	if (flags & MSG_CMSG_COMPAT)
2804 		return -EINVAL;
2805 
2806 	return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL, timeout);
2807 }
2808 #endif
2809 
2810 #ifdef __ARCH_WANT_SYS_SOCKETCALL
2811 /* Argument list sizes for sys_socketcall */
2812 #define AL(x) ((x) * sizeof(unsigned long))
2813 static const unsigned char nargs[21] = {
2814 	AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
2815 	AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
2816 	AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
2817 	AL(4), AL(5), AL(4)
2818 };
2819 
2820 #undef AL
2821 
2822 /*
2823  *	System call vectors.
2824  *
2825  *	Argument checking cleaned up. Saved 20% in size.
2826  *  This function doesn't need to set the kernel lock because
2827  *  it is set by the callees.
2828  */
2829 
2830 SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
2831 {
2832 	unsigned long a[AUDITSC_ARGS];
2833 	unsigned long a0, a1;
2834 	int err;
2835 	unsigned int len;
2836 
2837 	if (call < 1 || call > SYS_SENDMMSG)
2838 		return -EINVAL;
2839 	call = array_index_nospec(call, SYS_SENDMMSG + 1);
2840 
2841 	len = nargs[call];
2842 	if (len > sizeof(a))
2843 		return -EINVAL;
2844 
2845 	/* copy_from_user should be SMP safe. */
2846 	if (copy_from_user(a, args, len))
2847 		return -EFAULT;
2848 
2849 	err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
2850 	if (err)
2851 		return err;
2852 
2853 	a0 = a[0];
2854 	a1 = a[1];
2855 
2856 	switch (call) {
2857 	case SYS_SOCKET:
2858 		err = __sys_socket(a0, a1, a[2]);
2859 		break;
2860 	case SYS_BIND:
2861 		err = __sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
2862 		break;
2863 	case SYS_CONNECT:
2864 		err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
2865 		break;
2866 	case SYS_LISTEN:
2867 		err = __sys_listen(a0, a1);
2868 		break;
2869 	case SYS_ACCEPT:
2870 		err = __sys_accept4(a0, (struct sockaddr __user *)a1,
2871 				    (int __user *)a[2], 0);
2872 		break;
2873 	case SYS_GETSOCKNAME:
2874 		err =
2875 		    __sys_getsockname(a0, (struct sockaddr __user *)a1,
2876 				      (int __user *)a[2]);
2877 		break;
2878 	case SYS_GETPEERNAME:
2879 		err =
2880 		    __sys_getpeername(a0, (struct sockaddr __user *)a1,
2881 				      (int __user *)a[2]);
2882 		break;
2883 	case SYS_SOCKETPAIR:
2884 		err = __sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
2885 		break;
2886 	case SYS_SEND:
2887 		err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
2888 				   NULL, 0);
2889 		break;
2890 	case SYS_SENDTO:
2891 		err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
2892 				   (struct sockaddr __user *)a[4], a[5]);
2893 		break;
2894 	case SYS_RECV:
2895 		err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2896 				     NULL, NULL);
2897 		break;
2898 	case SYS_RECVFROM:
2899 		err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2900 				     (struct sockaddr __user *)a[4],
2901 				     (int __user *)a[5]);
2902 		break;
2903 	case SYS_SHUTDOWN:
2904 		err = __sys_shutdown(a0, a1);
2905 		break;
2906 	case SYS_SETSOCKOPT:
2907 		err = __sys_setsockopt(a0, a1, a[2], (char __user *)a[3],
2908 				       a[4]);
2909 		break;
2910 	case SYS_GETSOCKOPT:
2911 		err =
2912 		    __sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
2913 				     (int __user *)a[4]);
2914 		break;
2915 	case SYS_SENDMSG:
2916 		err = __sys_sendmsg(a0, (struct user_msghdr __user *)a1,
2917 				    a[2], true);
2918 		break;
2919 	case SYS_SENDMMSG:
2920 		err = __sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2],
2921 				     a[3], true);
2922 		break;
2923 	case SYS_RECVMSG:
2924 		err = __sys_recvmsg(a0, (struct user_msghdr __user *)a1,
2925 				    a[2], true);
2926 		break;
2927 	case SYS_RECVMMSG:
2928 		if (IS_ENABLED(CONFIG_64BIT))
2929 			err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
2930 					     a[2], a[3],
2931 					     (struct __kernel_timespec __user *)a[4],
2932 					     NULL);
2933 		else
2934 			err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
2935 					     a[2], a[3], NULL,
2936 					     (struct old_timespec32 __user *)a[4]);
2937 		break;
2938 	case SYS_ACCEPT4:
2939 		err = __sys_accept4(a0, (struct sockaddr __user *)a1,
2940 				    (int __user *)a[2], a[3]);
2941 		break;
2942 	default:
2943 		err = -EINVAL;
2944 		break;
2945 	}
2946 	return err;
2947 }
2948 
2949 #endif				/* __ARCH_WANT_SYS_SOCKETCALL */
2950 
2951 /**
2952  *	sock_register - add a socket protocol handler
2953  *	@ops: description of protocol
2954  *
2955  *	This function is called by a protocol handler that wants to
2956  *	advertise its address family, and have it linked into the
2957  *	socket interface. The value ops->family corresponds to the
2958  *	socket system call protocol family.
2959  */
2960 int sock_register(const struct net_proto_family *ops)
2961 {
2962 	int err;
2963 
2964 	if (ops->family >= NPROTO) {
2965 		pr_crit("protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
2966 		return -ENOBUFS;
2967 	}
2968 
2969 	spin_lock(&net_family_lock);
2970 	if (rcu_dereference_protected(net_families[ops->family],
2971 				      lockdep_is_held(&net_family_lock)))
2972 		err = -EEXIST;
2973 	else {
2974 		rcu_assign_pointer(net_families[ops->family], ops);
2975 		err = 0;
2976 	}
2977 	spin_unlock(&net_family_lock);
2978 
2979 	pr_info("NET: Registered protocol family %d\n", ops->family);
2980 	return err;
2981 }
2982 EXPORT_SYMBOL(sock_register);
2983 
2984 /**
2985  *	sock_unregister - remove a protocol handler
2986  *	@family: protocol family to remove
2987  *
2988  *	This function is called by a protocol handler that wants to
2989  *	remove its address family, and have it unlinked from the
2990  *	new socket creation.
2991  *
2992  *	If protocol handler is a module, then it can use module reference
2993  *	counts to protect against new references. If protocol handler is not
2994  *	a module then it needs to provide its own protection in
2995  *	the ops->create routine.
2996  */
2997 void sock_unregister(int family)
2998 {
2999 	BUG_ON(family < 0 || family >= NPROTO);
3000 
3001 	spin_lock(&net_family_lock);
3002 	RCU_INIT_POINTER(net_families[family], NULL);
3003 	spin_unlock(&net_family_lock);
3004 
3005 	synchronize_rcu();
3006 
3007 	pr_info("NET: Unregistered protocol family %d\n", family);
3008 }
3009 EXPORT_SYMBOL(sock_unregister);
3010 
3011 bool sock_is_registered(int family)
3012 {
3013 	return family < NPROTO && rcu_access_pointer(net_families[family]);
3014 }
3015 
3016 static int __init sock_init(void)
3017 {
3018 	int err;
3019 	/*
3020 	 *      Initialize the network sysctl infrastructure.
3021 	 */
3022 	err = net_sysctl_init();
3023 	if (err)
3024 		goto out;
3025 
3026 	/*
3027 	 *      Initialize skbuff SLAB cache
3028 	 */
3029 	skb_init();
3030 
3031 	/*
3032 	 *      Initialize the protocols module.
3033 	 */
3034 
3035 	init_inodecache();
3036 
3037 	err = register_filesystem(&sock_fs_type);
3038 	if (err)
3039 		goto out_fs;
3040 	sock_mnt = kern_mount(&sock_fs_type);
3041 	if (IS_ERR(sock_mnt)) {
3042 		err = PTR_ERR(sock_mnt);
3043 		goto out_mount;
3044 	}
3045 
3046 	/* The real protocol initialization is performed in later initcalls.
3047 	 */
3048 
3049 #ifdef CONFIG_NETFILTER
3050 	err = netfilter_init();
3051 	if (err)
3052 		goto out;
3053 #endif
3054 
3055 	ptp_classifier_init();
3056 
3057 out:
3058 	return err;
3059 
3060 out_mount:
3061 	unregister_filesystem(&sock_fs_type);
3062 out_fs:
3063 	goto out;
3064 }
3065 
3066 core_initcall(sock_init);	/* early initcall */
3067 
3068 #ifdef CONFIG_PROC_FS
3069 void socket_seq_show(struct seq_file *seq)
3070 {
3071 	seq_printf(seq, "sockets: used %d\n",
3072 		   sock_inuse_get(seq->private));
3073 }
3074 #endif				/* CONFIG_PROC_FS */
3075 
3076 #ifdef CONFIG_COMPAT
3077 static int compat_dev_ifconf(struct net *net, struct compat_ifconf __user *uifc32)
3078 {
3079 	struct compat_ifconf ifc32;
3080 	struct ifconf ifc;
3081 	int err;
3082 
3083 	if (copy_from_user(&ifc32, uifc32, sizeof(struct compat_ifconf)))
3084 		return -EFAULT;
3085 
3086 	ifc.ifc_len = ifc32.ifc_len;
3087 	ifc.ifc_req = compat_ptr(ifc32.ifcbuf);
3088 
3089 	rtnl_lock();
3090 	err = dev_ifconf(net, &ifc, sizeof(struct compat_ifreq));
3091 	rtnl_unlock();
3092 	if (err)
3093 		return err;
3094 
3095 	ifc32.ifc_len = ifc.ifc_len;
3096 	if (copy_to_user(uifc32, &ifc32, sizeof(struct compat_ifconf)))
3097 		return -EFAULT;
3098 
3099 	return 0;
3100 }
3101 
3102 static int ethtool_ioctl(struct net *net, struct compat_ifreq __user *ifr32)
3103 {
3104 	struct compat_ethtool_rxnfc __user *compat_rxnfc;
3105 	bool convert_in = false, convert_out = false;
3106 	size_t buf_size = 0;
3107 	struct ethtool_rxnfc __user *rxnfc = NULL;
3108 	struct ifreq ifr;
3109 	u32 rule_cnt = 0, actual_rule_cnt;
3110 	u32 ethcmd;
3111 	u32 data;
3112 	int ret;
3113 
3114 	if (get_user(data, &ifr32->ifr_ifru.ifru_data))
3115 		return -EFAULT;
3116 
3117 	compat_rxnfc = compat_ptr(data);
3118 
3119 	if (get_user(ethcmd, &compat_rxnfc->cmd))
3120 		return -EFAULT;
3121 
3122 	/* Most ethtool structures are defined without padding.
3123 	 * Unfortunately struct ethtool_rxnfc is an exception.
3124 	 */
3125 	switch (ethcmd) {
3126 	default:
3127 		break;
3128 	case ETHTOOL_GRXCLSRLALL:
3129 		/* Buffer size is variable */
3130 		if (get_user(rule_cnt, &compat_rxnfc->rule_cnt))
3131 			return -EFAULT;
3132 		if (rule_cnt > KMALLOC_MAX_SIZE / sizeof(u32))
3133 			return -ENOMEM;
3134 		buf_size += rule_cnt * sizeof(u32);
3135 		/* fall through */
3136 	case ETHTOOL_GRXRINGS:
3137 	case ETHTOOL_GRXCLSRLCNT:
3138 	case ETHTOOL_GRXCLSRULE:
3139 	case ETHTOOL_SRXCLSRLINS:
3140 		convert_out = true;
3141 		/* fall through */
3142 	case ETHTOOL_SRXCLSRLDEL:
3143 		buf_size += sizeof(struct ethtool_rxnfc);
3144 		convert_in = true;
3145 		rxnfc = compat_alloc_user_space(buf_size);
3146 		break;
3147 	}
3148 
3149 	if (copy_from_user(&ifr.ifr_name, &ifr32->ifr_name, IFNAMSIZ))
3150 		return -EFAULT;
3151 
3152 	ifr.ifr_data = convert_in ? rxnfc : (void __user *)compat_rxnfc;
3153 
3154 	if (convert_in) {
3155 		/* We expect there to be holes between fs.m_ext and
3156 		 * fs.ring_cookie and at the end of fs, but nowhere else.
3157 		 */
3158 		BUILD_BUG_ON(offsetof(struct compat_ethtool_rxnfc, fs.m_ext) +
3159 			     sizeof(compat_rxnfc->fs.m_ext) !=
3160 			     offsetof(struct ethtool_rxnfc, fs.m_ext) +
3161 			     sizeof(rxnfc->fs.m_ext));
3162 		BUILD_BUG_ON(
3163 			offsetof(struct compat_ethtool_rxnfc, fs.location) -
3164 			offsetof(struct compat_ethtool_rxnfc, fs.ring_cookie) !=
3165 			offsetof(struct ethtool_rxnfc, fs.location) -
3166 			offsetof(struct ethtool_rxnfc, fs.ring_cookie));
3167 
3168 		if (copy_in_user(rxnfc, compat_rxnfc,
3169 				 (void __user *)(&rxnfc->fs.m_ext + 1) -
3170 				 (void __user *)rxnfc) ||
3171 		    copy_in_user(&rxnfc->fs.ring_cookie,
3172 				 &compat_rxnfc->fs.ring_cookie,
3173 				 (void __user *)(&rxnfc->fs.location + 1) -
3174 				 (void __user *)&rxnfc->fs.ring_cookie))
3175 			return -EFAULT;
3176 		if (ethcmd == ETHTOOL_GRXCLSRLALL) {
3177 			if (put_user(rule_cnt, &rxnfc->rule_cnt))
3178 				return -EFAULT;
3179 		} else if (copy_in_user(&rxnfc->rule_cnt,
3180 					&compat_rxnfc->rule_cnt,
3181 					sizeof(rxnfc->rule_cnt)))
3182 			return -EFAULT;
3183 	}
3184 
3185 	ret = dev_ioctl(net, SIOCETHTOOL, &ifr, NULL);
3186 	if (ret)
3187 		return ret;
3188 
3189 	if (convert_out) {
3190 		if (copy_in_user(compat_rxnfc, rxnfc,
3191 				 (const void __user *)(&rxnfc->fs.m_ext + 1) -
3192 				 (const void __user *)rxnfc) ||
3193 		    copy_in_user(&compat_rxnfc->fs.ring_cookie,
3194 				 &rxnfc->fs.ring_cookie,
3195 				 (const void __user *)(&rxnfc->fs.location + 1) -
3196 				 (const void __user *)&rxnfc->fs.ring_cookie) ||
3197 		    copy_in_user(&compat_rxnfc->rule_cnt, &rxnfc->rule_cnt,
3198 				 sizeof(rxnfc->rule_cnt)))
3199 			return -EFAULT;
3200 
3201 		if (ethcmd == ETHTOOL_GRXCLSRLALL) {
3202 			/* As an optimisation, we only copy the actual
3203 			 * number of rules that the underlying
3204 			 * function returned.  Since Mallory might
3205 			 * change the rule count in user memory, we
3206 			 * check that it is less than the rule count
3207 			 * originally given (as the user buffer size),
3208 			 * which has been range-checked.
3209 			 */
3210 			if (get_user(actual_rule_cnt, &rxnfc->rule_cnt))
3211 				return -EFAULT;
3212 			if (actual_rule_cnt < rule_cnt)
3213 				rule_cnt = actual_rule_cnt;
3214 			if (copy_in_user(&compat_rxnfc->rule_locs[0],
3215 					 &rxnfc->rule_locs[0],
3216 					 rule_cnt * sizeof(u32)))
3217 				return -EFAULT;
3218 		}
3219 	}
3220 
3221 	return 0;
3222 }
3223 
3224 static int compat_siocwandev(struct net *net, struct compat_ifreq __user *uifr32)
3225 {
3226 	compat_uptr_t uptr32;
3227 	struct ifreq ifr;
3228 	void __user *saved;
3229 	int err;
3230 
3231 	if (copy_from_user(&ifr, uifr32, sizeof(struct compat_ifreq)))
3232 		return -EFAULT;
3233 
3234 	if (get_user(uptr32, &uifr32->ifr_settings.ifs_ifsu))
3235 		return -EFAULT;
3236 
3237 	saved = ifr.ifr_settings.ifs_ifsu.raw_hdlc;
3238 	ifr.ifr_settings.ifs_ifsu.raw_hdlc = compat_ptr(uptr32);
3239 
3240 	err = dev_ioctl(net, SIOCWANDEV, &ifr, NULL);
3241 	if (!err) {
3242 		ifr.ifr_settings.ifs_ifsu.raw_hdlc = saved;
3243 		if (copy_to_user(uifr32, &ifr, sizeof(struct compat_ifreq)))
3244 			err = -EFAULT;
3245 	}
3246 	return err;
3247 }
3248 
3249 /* Handle ioctls that use ifreq::ifr_data and just need struct ifreq converted */
3250 static int compat_ifr_data_ioctl(struct net *net, unsigned int cmd,
3251 				 struct compat_ifreq __user *u_ifreq32)
3252 {
3253 	struct ifreq ifreq;
3254 	u32 data32;
3255 
3256 	if (copy_from_user(ifreq.ifr_name, u_ifreq32->ifr_name, IFNAMSIZ))
3257 		return -EFAULT;
3258 	if (get_user(data32, &u_ifreq32->ifr_data))
3259 		return -EFAULT;
3260 	ifreq.ifr_data = compat_ptr(data32);
3261 
3262 	return dev_ioctl(net, cmd, &ifreq, NULL);
3263 }
3264 
3265 static int compat_ifreq_ioctl(struct net *net, struct socket *sock,
3266 			      unsigned int cmd,
3267 			      struct compat_ifreq __user *uifr32)
3268 {
3269 	struct ifreq __user *uifr;
3270 	int err;
3271 
3272 	/* Handle the fact that while struct ifreq has the same *layout* on
3273 	 * 32/64 for everything but ifreq::ifru_ifmap and ifreq::ifru_data,
3274 	 * which are handled elsewhere, it still has different *size* due to
3275 	 * ifreq::ifru_ifmap (which is 16 bytes on 32 bit, 24 bytes on 64-bit,
3276 	 * resulting in struct ifreq being 32 and 40 bytes respectively).
3277 	 * As a result, if the struct happens to be at the end of a page and
3278 	 * the next page isn't readable/writable, we get a fault. To prevent
3279 	 * that, copy back and forth to the full size.
3280 	 */
3281 
3282 	uifr = compat_alloc_user_space(sizeof(*uifr));
3283 	if (copy_in_user(uifr, uifr32, sizeof(*uifr32)))
3284 		return -EFAULT;
3285 
3286 	err = sock_do_ioctl(net, sock, cmd, (unsigned long)uifr);
3287 
3288 	if (!err) {
3289 		switch (cmd) {
3290 		case SIOCGIFFLAGS:
3291 		case SIOCGIFMETRIC:
3292 		case SIOCGIFMTU:
3293 		case SIOCGIFMEM:
3294 		case SIOCGIFHWADDR:
3295 		case SIOCGIFINDEX:
3296 		case SIOCGIFADDR:
3297 		case SIOCGIFBRDADDR:
3298 		case SIOCGIFDSTADDR:
3299 		case SIOCGIFNETMASK:
3300 		case SIOCGIFPFLAGS:
3301 		case SIOCGIFTXQLEN:
3302 		case SIOCGMIIPHY:
3303 		case SIOCGMIIREG:
3304 		case SIOCGIFNAME:
3305 			if (copy_in_user(uifr32, uifr, sizeof(*uifr32)))
3306 				err = -EFAULT;
3307 			break;
3308 		}
3309 	}
3310 	return err;
3311 }
3312 
3313 static int compat_sioc_ifmap(struct net *net, unsigned int cmd,
3314 			struct compat_ifreq __user *uifr32)
3315 {
3316 	struct ifreq ifr;
3317 	struct compat_ifmap __user *uifmap32;
3318 	int err;
3319 
3320 	uifmap32 = &uifr32->ifr_ifru.ifru_map;
3321 	err = copy_from_user(&ifr, uifr32, sizeof(ifr.ifr_name));
3322 	err |= get_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
3323 	err |= get_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
3324 	err |= get_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
3325 	err |= get_user(ifr.ifr_map.irq, &uifmap32->irq);
3326 	err |= get_user(ifr.ifr_map.dma, &uifmap32->dma);
3327 	err |= get_user(ifr.ifr_map.port, &uifmap32->port);
3328 	if (err)
3329 		return -EFAULT;
3330 
3331 	err = dev_ioctl(net, cmd, &ifr, NULL);
3332 
3333 	if (cmd == SIOCGIFMAP && !err) {
3334 		err = copy_to_user(uifr32, &ifr, sizeof(ifr.ifr_name));
3335 		err |= put_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
3336 		err |= put_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
3337 		err |= put_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
3338 		err |= put_user(ifr.ifr_map.irq, &uifmap32->irq);
3339 		err |= put_user(ifr.ifr_map.dma, &uifmap32->dma);
3340 		err |= put_user(ifr.ifr_map.port, &uifmap32->port);
3341 		if (err)
3342 			err = -EFAULT;
3343 	}
3344 	return err;
3345 }
3346 
3347 struct rtentry32 {
3348 	u32		rt_pad1;
3349 	struct sockaddr rt_dst;         /* target address               */
3350 	struct sockaddr rt_gateway;     /* gateway addr (RTF_GATEWAY)   */
3351 	struct sockaddr rt_genmask;     /* target network mask (IP)     */
3352 	unsigned short	rt_flags;
3353 	short		rt_pad2;
3354 	u32		rt_pad3;
3355 	unsigned char	rt_tos;
3356 	unsigned char	rt_class;
3357 	short		rt_pad4;
3358 	short		rt_metric;      /* +1 for binary compatibility! */
3359 	/* char * */ u32 rt_dev;        /* forcing the device at add    */
3360 	u32		rt_mtu;         /* per route MTU/Window         */
3361 	u32		rt_window;      /* Window clamping              */
3362 	unsigned short  rt_irtt;        /* Initial RTT                  */
3363 };
3364 
3365 struct in6_rtmsg32 {
3366 	struct in6_addr		rtmsg_dst;
3367 	struct in6_addr		rtmsg_src;
3368 	struct in6_addr		rtmsg_gateway;
3369 	u32			rtmsg_type;
3370 	u16			rtmsg_dst_len;
3371 	u16			rtmsg_src_len;
3372 	u32			rtmsg_metric;
3373 	u32			rtmsg_info;
3374 	u32			rtmsg_flags;
3375 	s32			rtmsg_ifindex;
3376 };
3377 
3378 static int routing_ioctl(struct net *net, struct socket *sock,
3379 			 unsigned int cmd, void __user *argp)
3380 {
3381 	int ret;
3382 	void *r = NULL;
3383 	struct in6_rtmsg r6;
3384 	struct rtentry r4;
3385 	char devname[16];
3386 	u32 rtdev;
3387 	mm_segment_t old_fs = get_fs();
3388 
3389 	if (sock && sock->sk && sock->sk->sk_family == AF_INET6) { /* ipv6 */
3390 		struct in6_rtmsg32 __user *ur6 = argp;
3391 		ret = copy_from_user(&r6.rtmsg_dst, &(ur6->rtmsg_dst),
3392 			3 * sizeof(struct in6_addr));
3393 		ret |= get_user(r6.rtmsg_type, &(ur6->rtmsg_type));
3394 		ret |= get_user(r6.rtmsg_dst_len, &(ur6->rtmsg_dst_len));
3395 		ret |= get_user(r6.rtmsg_src_len, &(ur6->rtmsg_src_len));
3396 		ret |= get_user(r6.rtmsg_metric, &(ur6->rtmsg_metric));
3397 		ret |= get_user(r6.rtmsg_info, &(ur6->rtmsg_info));
3398 		ret |= get_user(r6.rtmsg_flags, &(ur6->rtmsg_flags));
3399 		ret |= get_user(r6.rtmsg_ifindex, &(ur6->rtmsg_ifindex));
3400 
3401 		r = (void *) &r6;
3402 	} else { /* ipv4 */
3403 		struct rtentry32 __user *ur4 = argp;
3404 		ret = copy_from_user(&r4.rt_dst, &(ur4->rt_dst),
3405 					3 * sizeof(struct sockaddr));
3406 		ret |= get_user(r4.rt_flags, &(ur4->rt_flags));
3407 		ret |= get_user(r4.rt_metric, &(ur4->rt_metric));
3408 		ret |= get_user(r4.rt_mtu, &(ur4->rt_mtu));
3409 		ret |= get_user(r4.rt_window, &(ur4->rt_window));
3410 		ret |= get_user(r4.rt_irtt, &(ur4->rt_irtt));
3411 		ret |= get_user(rtdev, &(ur4->rt_dev));
3412 		if (rtdev) {
3413 			ret |= copy_from_user(devname, compat_ptr(rtdev), 15);
3414 			r4.rt_dev = (char __user __force *)devname;
3415 			devname[15] = 0;
3416 		} else
3417 			r4.rt_dev = NULL;
3418 
3419 		r = (void *) &r4;
3420 	}
3421 
3422 	if (ret) {
3423 		ret = -EFAULT;
3424 		goto out;
3425 	}
3426 
3427 	set_fs(KERNEL_DS);
3428 	ret = sock_do_ioctl(net, sock, cmd, (unsigned long) r);
3429 	set_fs(old_fs);
3430 
3431 out:
3432 	return ret;
3433 }
3434 
3435 /* Since old style bridge ioctl's endup using SIOCDEVPRIVATE
3436  * for some operations; this forces use of the newer bridge-utils that
3437  * use compatible ioctls
3438  */
3439 static int old_bridge_ioctl(compat_ulong_t __user *argp)
3440 {
3441 	compat_ulong_t tmp;
3442 
3443 	if (get_user(tmp, argp))
3444 		return -EFAULT;
3445 	if (tmp == BRCTL_GET_VERSION)
3446 		return BRCTL_VERSION + 1;
3447 	return -EINVAL;
3448 }
3449 
3450 static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
3451 			 unsigned int cmd, unsigned long arg)
3452 {
3453 	void __user *argp = compat_ptr(arg);
3454 	struct sock *sk = sock->sk;
3455 	struct net *net = sock_net(sk);
3456 
3457 	if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))
3458 		return compat_ifr_data_ioctl(net, cmd, argp);
3459 
3460 	switch (cmd) {
3461 	case SIOCSIFBR:
3462 	case SIOCGIFBR:
3463 		return old_bridge_ioctl(argp);
3464 	case SIOCGIFCONF:
3465 		return compat_dev_ifconf(net, argp);
3466 	case SIOCETHTOOL:
3467 		return ethtool_ioctl(net, argp);
3468 	case SIOCWANDEV:
3469 		return compat_siocwandev(net, argp);
3470 	case SIOCGIFMAP:
3471 	case SIOCSIFMAP:
3472 		return compat_sioc_ifmap(net, cmd, argp);
3473 	case SIOCADDRT:
3474 	case SIOCDELRT:
3475 		return routing_ioctl(net, sock, cmd, argp);
3476 	case SIOCGSTAMP_OLD:
3477 	case SIOCGSTAMPNS_OLD:
3478 		if (!sock->ops->gettstamp)
3479 			return -ENOIOCTLCMD;
3480 		return sock->ops->gettstamp(sock, argp, cmd == SIOCGSTAMP_OLD,
3481 					    !COMPAT_USE_64BIT_TIME);
3482 
3483 	case SIOCBONDSLAVEINFOQUERY:
3484 	case SIOCBONDINFOQUERY:
3485 	case SIOCSHWTSTAMP:
3486 	case SIOCGHWTSTAMP:
3487 		return compat_ifr_data_ioctl(net, cmd, argp);
3488 
3489 	case FIOSETOWN:
3490 	case SIOCSPGRP:
3491 	case FIOGETOWN:
3492 	case SIOCGPGRP:
3493 	case SIOCBRADDBR:
3494 	case SIOCBRDELBR:
3495 	case SIOCGIFVLAN:
3496 	case SIOCSIFVLAN:
3497 	case SIOCADDDLCI:
3498 	case SIOCDELDLCI:
3499 	case SIOCGSKNS:
3500 	case SIOCGSTAMP_NEW:
3501 	case SIOCGSTAMPNS_NEW:
3502 		return sock_ioctl(file, cmd, arg);
3503 
3504 	case SIOCGIFFLAGS:
3505 	case SIOCSIFFLAGS:
3506 	case SIOCGIFMETRIC:
3507 	case SIOCSIFMETRIC:
3508 	case SIOCGIFMTU:
3509 	case SIOCSIFMTU:
3510 	case SIOCGIFMEM:
3511 	case SIOCSIFMEM:
3512 	case SIOCGIFHWADDR:
3513 	case SIOCSIFHWADDR:
3514 	case SIOCADDMULTI:
3515 	case SIOCDELMULTI:
3516 	case SIOCGIFINDEX:
3517 	case SIOCGIFADDR:
3518 	case SIOCSIFADDR:
3519 	case SIOCSIFHWBROADCAST:
3520 	case SIOCDIFADDR:
3521 	case SIOCGIFBRDADDR:
3522 	case SIOCSIFBRDADDR:
3523 	case SIOCGIFDSTADDR:
3524 	case SIOCSIFDSTADDR:
3525 	case SIOCGIFNETMASK:
3526 	case SIOCSIFNETMASK:
3527 	case SIOCSIFPFLAGS:
3528 	case SIOCGIFPFLAGS:
3529 	case SIOCGIFTXQLEN:
3530 	case SIOCSIFTXQLEN:
3531 	case SIOCBRADDIF:
3532 	case SIOCBRDELIF:
3533 	case SIOCGIFNAME:
3534 	case SIOCSIFNAME:
3535 	case SIOCGMIIPHY:
3536 	case SIOCGMIIREG:
3537 	case SIOCSMIIREG:
3538 	case SIOCBONDENSLAVE:
3539 	case SIOCBONDRELEASE:
3540 	case SIOCBONDSETHWADDR:
3541 	case SIOCBONDCHANGEACTIVE:
3542 		return compat_ifreq_ioctl(net, sock, cmd, argp);
3543 
3544 	case SIOCSARP:
3545 	case SIOCGARP:
3546 	case SIOCDARP:
3547 	case SIOCOUTQ:
3548 	case SIOCOUTQNSD:
3549 	case SIOCATMARK:
3550 		return sock_do_ioctl(net, sock, cmd, arg);
3551 	}
3552 
3553 	return -ENOIOCTLCMD;
3554 }
3555 
3556 static long compat_sock_ioctl(struct file *file, unsigned int cmd,
3557 			      unsigned long arg)
3558 {
3559 	struct socket *sock = file->private_data;
3560 	int ret = -ENOIOCTLCMD;
3561 	struct sock *sk;
3562 	struct net *net;
3563 
3564 	sk = sock->sk;
3565 	net = sock_net(sk);
3566 
3567 	if (sock->ops->compat_ioctl)
3568 		ret = sock->ops->compat_ioctl(sock, cmd, arg);
3569 
3570 	if (ret == -ENOIOCTLCMD &&
3571 	    (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
3572 		ret = compat_wext_handle_ioctl(net, cmd, arg);
3573 
3574 	if (ret == -ENOIOCTLCMD)
3575 		ret = compat_sock_ioctl_trans(file, sock, cmd, arg);
3576 
3577 	return ret;
3578 }
3579 #endif
3580 
3581 /**
3582  *	kernel_bind - bind an address to a socket (kernel space)
3583  *	@sock: socket
3584  *	@addr: address
3585  *	@addrlen: length of address
3586  *
3587  *	Returns 0 or an error.
3588  */
3589 
3590 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
3591 {
3592 	return sock->ops->bind(sock, addr, addrlen);
3593 }
3594 EXPORT_SYMBOL(kernel_bind);
3595 
3596 /**
3597  *	kernel_listen - move socket to listening state (kernel space)
3598  *	@sock: socket
3599  *	@backlog: pending connections queue size
3600  *
3601  *	Returns 0 or an error.
3602  */
3603 
3604 int kernel_listen(struct socket *sock, int backlog)
3605 {
3606 	return sock->ops->listen(sock, backlog);
3607 }
3608 EXPORT_SYMBOL(kernel_listen);
3609 
3610 /**
3611  *	kernel_accept - accept a connection (kernel space)
3612  *	@sock: listening socket
3613  *	@newsock: new connected socket
3614  *	@flags: flags
3615  *
3616  *	@flags must be SOCK_CLOEXEC, SOCK_NONBLOCK or 0.
3617  *	If it fails, @newsock is guaranteed to be %NULL.
3618  *	Returns 0 or an error.
3619  */
3620 
3621 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
3622 {
3623 	struct sock *sk = sock->sk;
3624 	int err;
3625 
3626 	err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
3627 			       newsock);
3628 	if (err < 0)
3629 		goto done;
3630 
3631 	err = sock->ops->accept(sock, *newsock, flags, true);
3632 	if (err < 0) {
3633 		sock_release(*newsock);
3634 		*newsock = NULL;
3635 		goto done;
3636 	}
3637 
3638 	(*newsock)->ops = sock->ops;
3639 	__module_get((*newsock)->ops->owner);
3640 
3641 done:
3642 	return err;
3643 }
3644 EXPORT_SYMBOL(kernel_accept);
3645 
3646 /**
3647  *	kernel_connect - connect a socket (kernel space)
3648  *	@sock: socket
3649  *	@addr: address
3650  *	@addrlen: address length
3651  *	@flags: flags (O_NONBLOCK, ...)
3652  *
3653  *	For datagram sockets, @addr is the addres to which datagrams are sent
3654  *	by default, and the only address from which datagrams are received.
3655  *	For stream sockets, attempts to connect to @addr.
3656  *	Returns 0 or an error code.
3657  */
3658 
3659 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
3660 		   int flags)
3661 {
3662 	return sock->ops->connect(sock, addr, addrlen, flags);
3663 }
3664 EXPORT_SYMBOL(kernel_connect);
3665 
3666 /**
3667  *	kernel_getsockname - get the address which the socket is bound (kernel space)
3668  *	@sock: socket
3669  *	@addr: address holder
3670  *
3671  * 	Fills the @addr pointer with the address which the socket is bound.
3672  *	Returns 0 or an error code.
3673  */
3674 
3675 int kernel_getsockname(struct socket *sock, struct sockaddr *addr)
3676 {
3677 	return sock->ops->getname(sock, addr, 0);
3678 }
3679 EXPORT_SYMBOL(kernel_getsockname);
3680 
3681 /**
3682  *	kernel_peername - get the address which the socket is connected (kernel space)
3683  *	@sock: socket
3684  *	@addr: address holder
3685  *
3686  * 	Fills the @addr pointer with the address which the socket is connected.
3687  *	Returns 0 or an error code.
3688  */
3689 
3690 int kernel_getpeername(struct socket *sock, struct sockaddr *addr)
3691 {
3692 	return sock->ops->getname(sock, addr, 1);
3693 }
3694 EXPORT_SYMBOL(kernel_getpeername);
3695 
3696 /**
3697  *	kernel_getsockopt - get a socket option (kernel space)
3698  *	@sock: socket
3699  *	@level: API level (SOL_SOCKET, ...)
3700  *	@optname: option tag
3701  *	@optval: option value
3702  *	@optlen: option length
3703  *
3704  *	Assigns the option length to @optlen.
3705  *	Returns 0 or an error.
3706  */
3707 
3708 int kernel_getsockopt(struct socket *sock, int level, int optname,
3709 			char *optval, int *optlen)
3710 {
3711 	mm_segment_t oldfs = get_fs();
3712 	char __user *uoptval;
3713 	int __user *uoptlen;
3714 	int err;
3715 
3716 	uoptval = (char __user __force *) optval;
3717 	uoptlen = (int __user __force *) optlen;
3718 
3719 	set_fs(KERNEL_DS);
3720 	if (level == SOL_SOCKET)
3721 		err = sock_getsockopt(sock, level, optname, uoptval, uoptlen);
3722 	else
3723 		err = sock->ops->getsockopt(sock, level, optname, uoptval,
3724 					    uoptlen);
3725 	set_fs(oldfs);
3726 	return err;
3727 }
3728 EXPORT_SYMBOL(kernel_getsockopt);
3729 
3730 /**
3731  *	kernel_setsockopt - set a socket option (kernel space)
3732  *	@sock: socket
3733  *	@level: API level (SOL_SOCKET, ...)
3734  *	@optname: option tag
3735  *	@optval: option value
3736  *	@optlen: option length
3737  *
3738  *	Returns 0 or an error.
3739  */
3740 
3741 int kernel_setsockopt(struct socket *sock, int level, int optname,
3742 			char *optval, unsigned int optlen)
3743 {
3744 	mm_segment_t oldfs = get_fs();
3745 	char __user *uoptval;
3746 	int err;
3747 
3748 	uoptval = (char __user __force *) optval;
3749 
3750 	set_fs(KERNEL_DS);
3751 	if (level == SOL_SOCKET)
3752 		err = sock_setsockopt(sock, level, optname, uoptval, optlen);
3753 	else
3754 		err = sock->ops->setsockopt(sock, level, optname, uoptval,
3755 					    optlen);
3756 	set_fs(oldfs);
3757 	return err;
3758 }
3759 EXPORT_SYMBOL(kernel_setsockopt);
3760 
3761 /**
3762  *	kernel_sendpage - send a &page through a socket (kernel space)
3763  *	@sock: socket
3764  *	@page: page
3765  *	@offset: page offset
3766  *	@size: total size in bytes
3767  *	@flags: flags (MSG_DONTWAIT, ...)
3768  *
3769  *	Returns the total amount sent in bytes or an error.
3770  */
3771 
3772 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
3773 		    size_t size, int flags)
3774 {
3775 	if (sock->ops->sendpage)
3776 		return sock->ops->sendpage(sock, page, offset, size, flags);
3777 
3778 	return sock_no_sendpage(sock, page, offset, size, flags);
3779 }
3780 EXPORT_SYMBOL(kernel_sendpage);
3781 
3782 /**
3783  *	kernel_sendpage_locked - send a &page through the locked sock (kernel space)
3784  *	@sk: sock
3785  *	@page: page
3786  *	@offset: page offset
3787  *	@size: total size in bytes
3788  *	@flags: flags (MSG_DONTWAIT, ...)
3789  *
3790  *	Returns the total amount sent in bytes or an error.
3791  *	Caller must hold @sk.
3792  */
3793 
3794 int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
3795 			   size_t size, int flags)
3796 {
3797 	struct socket *sock = sk->sk_socket;
3798 
3799 	if (sock->ops->sendpage_locked)
3800 		return sock->ops->sendpage_locked(sk, page, offset, size,
3801 						  flags);
3802 
3803 	return sock_no_sendpage_locked(sk, page, offset, size, flags);
3804 }
3805 EXPORT_SYMBOL(kernel_sendpage_locked);
3806 
3807 /**
3808  *	kernel_shutdown - shut down part of a full-duplex connection (kernel space)
3809  *	@sock: socket
3810  *	@how: connection part
3811  *
3812  *	Returns 0 or an error.
3813  */
3814 
3815 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
3816 {
3817 	return sock->ops->shutdown(sock, how);
3818 }
3819 EXPORT_SYMBOL(kernel_sock_shutdown);
3820 
3821 /**
3822  *	kernel_sock_ip_overhead - returns the IP overhead imposed by a socket
3823  *	@sk: socket
3824  *
3825  *	This routine returns the IP overhead imposed by a socket i.e.
3826  *	the length of the underlying IP header, depending on whether
3827  *	this is an IPv4 or IPv6 socket and the length from IP options turned
3828  *	on at the socket. Assumes that the caller has a lock on the socket.
3829  */
3830 
3831 u32 kernel_sock_ip_overhead(struct sock *sk)
3832 {
3833 	struct inet_sock *inet;
3834 	struct ip_options_rcu *opt;
3835 	u32 overhead = 0;
3836 #if IS_ENABLED(CONFIG_IPV6)
3837 	struct ipv6_pinfo *np;
3838 	struct ipv6_txoptions *optv6 = NULL;
3839 #endif /* IS_ENABLED(CONFIG_IPV6) */
3840 
3841 	if (!sk)
3842 		return overhead;
3843 
3844 	switch (sk->sk_family) {
3845 	case AF_INET:
3846 		inet = inet_sk(sk);
3847 		overhead += sizeof(struct iphdr);
3848 		opt = rcu_dereference_protected(inet->inet_opt,
3849 						sock_owned_by_user(sk));
3850 		if (opt)
3851 			overhead += opt->opt.optlen;
3852 		return overhead;
3853 #if IS_ENABLED(CONFIG_IPV6)
3854 	case AF_INET6:
3855 		np = inet6_sk(sk);
3856 		overhead += sizeof(struct ipv6hdr);
3857 		if (np)
3858 			optv6 = rcu_dereference_protected(np->opt,
3859 							  sock_owned_by_user(sk));
3860 		if (optv6)
3861 			overhead += (optv6->opt_flen + optv6->opt_nflen);
3862 		return overhead;
3863 #endif /* IS_ENABLED(CONFIG_IPV6) */
3864 	default: /* Returns 0 overhead if the socket is not ipv4 or ipv6 */
3865 		return overhead;
3866 	}
3867 }
3868 EXPORT_SYMBOL(kernel_sock_ip_overhead);
3869