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Linux/net/socket.c

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  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/bpf-cgroup.h>
 56 #include <linux/ethtool.h>
 57 #include <linux/mm.h>
 58 #include <linux/socket.h>
 59 #include <linux/file.h>
 60 #include <linux/splice.h>
 61 #include <linux/net.h>
 62 #include <linux/interrupt.h>
 63 #include <linux/thread_info.h>
 64 #include <linux/rcupdate.h>
 65 #include <linux/netdevice.h>
 66 #include <linux/proc_fs.h>
 67 #include <linux/seq_file.h>
 68 #include <linux/mutex.h>
 69 #include <linux/if_bridge.h>
 70 #include <linux/if_vlan.h>
 71 #include <linux/ptp_classify.h>
 72 #include <linux/init.h>
 73 #include <linux/poll.h>
 74 #include <linux/cache.h>
 75 #include <linux/module.h>
 76 #include <linux/highmem.h>
 77 #include <linux/mount.h>
 78 #include <linux/pseudo_fs.h>
 79 #include <linux/security.h>
 80 #include <linux/syscalls.h>
 81 #include <linux/compat.h>
 82 #include <linux/kmod.h>
 83 #include <linux/audit.h>
 84 #include <linux/wireless.h>
 85 #include <linux/nsproxy.h>
 86 #include <linux/magic.h>
 87 #include <linux/slab.h>
 88 #include <linux/xattr.h>
 89 #include <linux/nospec.h>
 90 #include <linux/indirect_call_wrapper.h>
 91 #include <linux/io_uring/net.h>
 92 
 93 #include <linux/uaccess.h>
 94 #include <asm/unistd.h>
 95 
 96 #include <net/compat.h>
 97 #include <net/wext.h>
 98 #include <net/cls_cgroup.h>
 99 
100 #include <net/sock.h>
101 #include <linux/netfilter.h>
102 
103 #include <linux/if_tun.h>
104 #include <linux/ipv6_route.h>
105 #include <linux/route.h>
106 #include <linux/termios.h>
107 #include <linux/sockios.h>
108 #include <net/busy_poll.h>
109 #include <linux/errqueue.h>
110 #include <linux/ptp_clock_kernel.h>
111 #include <trace/events/sock.h>
112 
113 #ifdef CONFIG_NET_RX_BUSY_POLL
114 unsigned int sysctl_net_busy_read __read_mostly;
115 unsigned int sysctl_net_busy_poll __read_mostly;
116 #endif
117 
118 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to);
119 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
120 static int sock_mmap(struct file *file, struct vm_area_struct *vma);
121 
122 static int sock_close(struct inode *inode, struct file *file);
123 static __poll_t sock_poll(struct file *file,
124                               struct poll_table_struct *wait);
125 static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
126 #ifdef CONFIG_COMPAT
127 static long compat_sock_ioctl(struct file *file,
128                               unsigned int cmd, unsigned long arg);
129 #endif
130 static int sock_fasync(int fd, struct file *filp, int on);
131 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
132                                 struct pipe_inode_info *pipe, size_t len,
133                                 unsigned int flags);
134 static void sock_splice_eof(struct file *file);
135 
136 #ifdef CONFIG_PROC_FS
137 static void sock_show_fdinfo(struct seq_file *m, struct file *f)
138 {
139         struct socket *sock = f->private_data;
140         const struct proto_ops *ops = READ_ONCE(sock->ops);
141 
142         if (ops->show_fdinfo)
143                 ops->show_fdinfo(m, sock);
144 }
145 #else
146 #define sock_show_fdinfo NULL
147 #endif
148 
149 /*
150  *      Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
151  *      in the operation structures but are done directly via the socketcall() multiplexor.
152  */
153 
154 static const struct file_operations socket_file_ops = {
155         .owner =        THIS_MODULE,
156         .llseek =       no_llseek,
157         .read_iter =    sock_read_iter,
158         .write_iter =   sock_write_iter,
159         .poll =         sock_poll,
160         .unlocked_ioctl = sock_ioctl,
161 #ifdef CONFIG_COMPAT
162         .compat_ioctl = compat_sock_ioctl,
163 #endif
164         .uring_cmd =    io_uring_cmd_sock,
165         .mmap =         sock_mmap,
166         .release =      sock_close,
167         .fasync =       sock_fasync,
168         .splice_write = splice_to_socket,
169         .splice_read =  sock_splice_read,
170         .splice_eof =   sock_splice_eof,
171         .show_fdinfo =  sock_show_fdinfo,
172 };
173 
174 static const char * const pf_family_names[] = {
175         [PF_UNSPEC]     = "PF_UNSPEC",
176         [PF_UNIX]       = "PF_UNIX/PF_LOCAL",
177         [PF_INET]       = "PF_INET",
178         [PF_AX25]       = "PF_AX25",
179         [PF_IPX]        = "PF_IPX",
180         [PF_APPLETALK]  = "PF_APPLETALK",
181         [PF_NETROM]     = "PF_NETROM",
182         [PF_BRIDGE]     = "PF_BRIDGE",
183         [PF_ATMPVC]     = "PF_ATMPVC",
184         [PF_X25]        = "PF_X25",
185         [PF_INET6]      = "PF_INET6",
186         [PF_ROSE]       = "PF_ROSE",
187         [PF_DECnet]     = "PF_DECnet",
188         [PF_NETBEUI]    = "PF_NETBEUI",
189         [PF_SECURITY]   = "PF_SECURITY",
190         [PF_KEY]        = "PF_KEY",
191         [PF_NETLINK]    = "PF_NETLINK/PF_ROUTE",
192         [PF_PACKET]     = "PF_PACKET",
193         [PF_ASH]        = "PF_ASH",
194         [PF_ECONET]     = "PF_ECONET",
195         [PF_ATMSVC]     = "PF_ATMSVC",
196         [PF_RDS]        = "PF_RDS",
197         [PF_SNA]        = "PF_SNA",
198         [PF_IRDA]       = "PF_IRDA",
199         [PF_PPPOX]      = "PF_PPPOX",
200         [PF_WANPIPE]    = "PF_WANPIPE",
201         [PF_LLC]        = "PF_LLC",
202         [PF_IB]         = "PF_IB",
203         [PF_MPLS]       = "PF_MPLS",
204         [PF_CAN]        = "PF_CAN",
205         [PF_TIPC]       = "PF_TIPC",
206         [PF_BLUETOOTH]  = "PF_BLUETOOTH",
207         [PF_IUCV]       = "PF_IUCV",
208         [PF_RXRPC]      = "PF_RXRPC",
209         [PF_ISDN]       = "PF_ISDN",
210         [PF_PHONET]     = "PF_PHONET",
211         [PF_IEEE802154] = "PF_IEEE802154",
212         [PF_CAIF]       = "PF_CAIF",
213         [PF_ALG]        = "PF_ALG",
214         [PF_NFC]        = "PF_NFC",
215         [PF_VSOCK]      = "PF_VSOCK",
216         [PF_KCM]        = "PF_KCM",
217         [PF_QIPCRTR]    = "PF_QIPCRTR",
218         [PF_SMC]        = "PF_SMC",
219         [PF_XDP]        = "PF_XDP",
220         [PF_MCTP]       = "PF_MCTP",
221 };
222 
223 /*
224  *      The protocol list. Each protocol is registered in here.
225  */
226 
227 static DEFINE_SPINLOCK(net_family_lock);
228 static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
229 
230 /*
231  * Support routines.
232  * Move socket addresses back and forth across the kernel/user
233  * divide and look after the messy bits.
234  */
235 
236 /**
237  *      move_addr_to_kernel     -       copy a socket address into kernel space
238  *      @uaddr: Address in user space
239  *      @kaddr: Address in kernel space
240  *      @ulen: Length in user space
241  *
242  *      The address is copied into kernel space. If the provided address is
243  *      too long an error code of -EINVAL is returned. If the copy gives
244  *      invalid addresses -EFAULT is returned. On a success 0 is returned.
245  */
246 
247 int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
248 {
249         if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
250                 return -EINVAL;
251         if (ulen == 0)
252                 return 0;
253         if (copy_from_user(kaddr, uaddr, ulen))
254                 return -EFAULT;
255         return audit_sockaddr(ulen, kaddr);
256 }
257 
258 /**
259  *      move_addr_to_user       -       copy an address to user space
260  *      @kaddr: kernel space address
261  *      @klen: length of address in kernel
262  *      @uaddr: user space address
263  *      @ulen: pointer to user length field
264  *
265  *      The value pointed to by ulen on entry is the buffer length available.
266  *      This is overwritten with the buffer space used. -EINVAL is returned
267  *      if an overlong buffer is specified or a negative buffer size. -EFAULT
268  *      is returned if either the buffer or the length field are not
269  *      accessible.
270  *      After copying the data up to the limit the user specifies, the true
271  *      length of the data is written over the length limit the user
272  *      specified. Zero is returned for a success.
273  */
274 
275 static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
276                              void __user *uaddr, int __user *ulen)
277 {
278         int err;
279         int len;
280 
281         BUG_ON(klen > sizeof(struct sockaddr_storage));
282         err = get_user(len, ulen);
283         if (err)
284                 return err;
285         if (len > klen)
286                 len = klen;
287         if (len < 0)
288                 return -EINVAL;
289         if (len) {
290                 if (audit_sockaddr(klen, kaddr))
291                         return -ENOMEM;
292                 if (copy_to_user(uaddr, kaddr, len))
293                         return -EFAULT;
294         }
295         /*
296          *      "fromlen shall refer to the value before truncation.."
297          *                      1003.1g
298          */
299         return __put_user(klen, ulen);
300 }
301 
302 static struct kmem_cache *sock_inode_cachep __ro_after_init;
303 
304 static struct inode *sock_alloc_inode(struct super_block *sb)
305 {
306         struct socket_alloc *ei;
307 
308         ei = alloc_inode_sb(sb, sock_inode_cachep, GFP_KERNEL);
309         if (!ei)
310                 return NULL;
311         init_waitqueue_head(&ei->socket.wq.wait);
312         ei->socket.wq.fasync_list = NULL;
313         ei->socket.wq.flags = 0;
314 
315         ei->socket.state = SS_UNCONNECTED;
316         ei->socket.flags = 0;
317         ei->socket.ops = NULL;
318         ei->socket.sk = NULL;
319         ei->socket.file = NULL;
320 
321         return &ei->vfs_inode;
322 }
323 
324 static void sock_free_inode(struct inode *inode)
325 {
326         struct socket_alloc *ei;
327 
328         ei = container_of(inode, struct socket_alloc, vfs_inode);
329         kmem_cache_free(sock_inode_cachep, ei);
330 }
331 
332 static void init_once(void *foo)
333 {
334         struct socket_alloc *ei = (struct socket_alloc *)foo;
335 
336         inode_init_once(&ei->vfs_inode);
337 }
338 
339 static void init_inodecache(void)
340 {
341         sock_inode_cachep = kmem_cache_create("sock_inode_cache",
342                                               sizeof(struct socket_alloc),
343                                               0,
344                                               (SLAB_HWCACHE_ALIGN |
345                                                SLAB_RECLAIM_ACCOUNT |
346                                                SLAB_ACCOUNT),
347                                               init_once);
348         BUG_ON(sock_inode_cachep == NULL);
349 }
350 
351 static const struct super_operations sockfs_ops = {
352         .alloc_inode    = sock_alloc_inode,
353         .free_inode     = sock_free_inode,
354         .statfs         = simple_statfs,
355 };
356 
357 /*
358  * sockfs_dname() is called from d_path().
359  */
360 static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
361 {
362         return dynamic_dname(buffer, buflen, "socket:[%lu]",
363                                 d_inode(dentry)->i_ino);
364 }
365 
366 static const struct dentry_operations sockfs_dentry_operations = {
367         .d_dname  = sockfs_dname,
368 };
369 
370 static int sockfs_xattr_get(const struct xattr_handler *handler,
371                             struct dentry *dentry, struct inode *inode,
372                             const char *suffix, void *value, size_t size)
373 {
374         if (value) {
375                 if (dentry->d_name.len + 1 > size)
376                         return -ERANGE;
377                 memcpy(value, dentry->d_name.name, dentry->d_name.len + 1);
378         }
379         return dentry->d_name.len + 1;
380 }
381 
382 #define XATTR_SOCKPROTONAME_SUFFIX "sockprotoname"
383 #define XATTR_NAME_SOCKPROTONAME (XATTR_SYSTEM_PREFIX XATTR_SOCKPROTONAME_SUFFIX)
384 #define XATTR_NAME_SOCKPROTONAME_LEN (sizeof(XATTR_NAME_SOCKPROTONAME)-1)
385 
386 static const struct xattr_handler sockfs_xattr_handler = {
387         .name = XATTR_NAME_SOCKPROTONAME,
388         .get = sockfs_xattr_get,
389 };
390 
391 static int sockfs_security_xattr_set(const struct xattr_handler *handler,
392                                      struct mnt_idmap *idmap,
393                                      struct dentry *dentry, struct inode *inode,
394                                      const char *suffix, const void *value,
395                                      size_t size, int flags)
396 {
397         /* Handled by LSM. */
398         return -EAGAIN;
399 }
400 
401 static const struct xattr_handler sockfs_security_xattr_handler = {
402         .prefix = XATTR_SECURITY_PREFIX,
403         .set = sockfs_security_xattr_set,
404 };
405 
406 static const struct xattr_handler * const sockfs_xattr_handlers[] = {
407         &sockfs_xattr_handler,
408         &sockfs_security_xattr_handler,
409         NULL
410 };
411 
412 static int sockfs_init_fs_context(struct fs_context *fc)
413 {
414         struct pseudo_fs_context *ctx = init_pseudo(fc, SOCKFS_MAGIC);
415         if (!ctx)
416                 return -ENOMEM;
417         ctx->ops = &sockfs_ops;
418         ctx->dops = &sockfs_dentry_operations;
419         ctx->xattr = sockfs_xattr_handlers;
420         return 0;
421 }
422 
423 static struct vfsmount *sock_mnt __read_mostly;
424 
425 static struct file_system_type sock_fs_type = {
426         .name =         "sockfs",
427         .init_fs_context = sockfs_init_fs_context,
428         .kill_sb =      kill_anon_super,
429 };
430 
431 /*
432  *      Obtains the first available file descriptor and sets it up for use.
433  *
434  *      These functions create file structures and maps them to fd space
435  *      of the current process. On success it returns file descriptor
436  *      and file struct implicitly stored in sock->file.
437  *      Note that another thread may close file descriptor before we return
438  *      from this function. We use the fact that now we do not refer
439  *      to socket after mapping. If one day we will need it, this
440  *      function will increment ref. count on file by 1.
441  *
442  *      In any case returned fd MAY BE not valid!
443  *      This race condition is unavoidable
444  *      with shared fd spaces, we cannot solve it inside kernel,
445  *      but we take care of internal coherence yet.
446  */
447 
448 /**
449  *      sock_alloc_file - Bind a &socket to a &file
450  *      @sock: socket
451  *      @flags: file status flags
452  *      @dname: protocol name
453  *
454  *      Returns the &file bound with @sock, implicitly storing it
455  *      in sock->file. If dname is %NULL, sets to "".
456  *
457  *      On failure @sock is released, and an ERR pointer is returned.
458  *
459  *      This function uses GFP_KERNEL internally.
460  */
461 
462 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
463 {
464         struct file *file;
465 
466         if (!dname)
467                 dname = sock->sk ? sock->sk->sk_prot_creator->name : "";
468 
469         file = alloc_file_pseudo(SOCK_INODE(sock), sock_mnt, dname,
470                                 O_RDWR | (flags & O_NONBLOCK),
471                                 &socket_file_ops);
472         if (IS_ERR(file)) {
473                 sock_release(sock);
474                 return file;
475         }
476 
477         file->f_mode |= FMODE_NOWAIT;
478         sock->file = file;
479         file->private_data = sock;
480         stream_open(SOCK_INODE(sock), file);
481         return file;
482 }
483 EXPORT_SYMBOL(sock_alloc_file);
484 
485 static int sock_map_fd(struct socket *sock, int flags)
486 {
487         struct file *newfile;
488         int fd = get_unused_fd_flags(flags);
489         if (unlikely(fd < 0)) {
490                 sock_release(sock);
491                 return fd;
492         }
493 
494         newfile = sock_alloc_file(sock, flags, NULL);
495         if (!IS_ERR(newfile)) {
496                 fd_install(fd, newfile);
497                 return fd;
498         }
499 
500         put_unused_fd(fd);
501         return PTR_ERR(newfile);
502 }
503 
504 /**
505  *      sock_from_file - Return the &socket bounded to @file.
506  *      @file: file
507  *
508  *      On failure returns %NULL.
509  */
510 
511 struct socket *sock_from_file(struct file *file)
512 {
513         if (file->f_op == &socket_file_ops)
514                 return file->private_data;      /* set in sock_alloc_file */
515 
516         return NULL;
517 }
518 EXPORT_SYMBOL(sock_from_file);
519 
520 /**
521  *      sockfd_lookup - Go from a file number to its socket slot
522  *      @fd: file handle
523  *      @err: pointer to an error code return
524  *
525  *      The file handle passed in is locked and the socket it is bound
526  *      to is returned. If an error occurs the err pointer is overwritten
527  *      with a negative errno code and NULL is returned. The function checks
528  *      for both invalid handles and passing a handle which is not a socket.
529  *
530  *      On a success the socket object pointer is returned.
531  */
532 
533 struct socket *sockfd_lookup(int fd, int *err)
534 {
535         struct file *file;
536         struct socket *sock;
537 
538         file = fget(fd);
539         if (!file) {
540                 *err = -EBADF;
541                 return NULL;
542         }
543 
544         sock = sock_from_file(file);
545         if (!sock) {
546                 *err = -ENOTSOCK;
547                 fput(file);
548         }
549         return sock;
550 }
551 EXPORT_SYMBOL(sockfd_lookup);
552 
553 static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
554 {
555         struct fd f = fdget(fd);
556         struct socket *sock;
557 
558         *err = -EBADF;
559         if (f.file) {
560                 sock = sock_from_file(f.file);
561                 if (likely(sock)) {
562                         *fput_needed = f.flags & FDPUT_FPUT;
563                         return sock;
564                 }
565                 *err = -ENOTSOCK;
566                 fdput(f);
567         }
568         return NULL;
569 }
570 
571 static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
572                                 size_t size)
573 {
574         ssize_t len;
575         ssize_t used = 0;
576 
577         len = security_inode_listsecurity(d_inode(dentry), buffer, size);
578         if (len < 0)
579                 return len;
580         used += len;
581         if (buffer) {
582                 if (size < used)
583                         return -ERANGE;
584                 buffer += len;
585         }
586 
587         len = (XATTR_NAME_SOCKPROTONAME_LEN + 1);
588         used += len;
589         if (buffer) {
590                 if (size < used)
591                         return -ERANGE;
592                 memcpy(buffer, XATTR_NAME_SOCKPROTONAME, len);
593                 buffer += len;
594         }
595 
596         return used;
597 }
598 
599 static int sockfs_setattr(struct mnt_idmap *idmap,
600                           struct dentry *dentry, struct iattr *iattr)
601 {
602         int err = simple_setattr(&nop_mnt_idmap, dentry, iattr);
603 
604         if (!err && (iattr->ia_valid & ATTR_UID)) {
605                 struct socket *sock = SOCKET_I(d_inode(dentry));
606 
607                 if (sock->sk)
608                         sock->sk->sk_uid = iattr->ia_uid;
609                 else
610                         err = -ENOENT;
611         }
612 
613         return err;
614 }
615 
616 static const struct inode_operations sockfs_inode_ops = {
617         .listxattr = sockfs_listxattr,
618         .setattr = sockfs_setattr,
619 };
620 
621 /**
622  *      sock_alloc - allocate a socket
623  *
624  *      Allocate a new inode and socket object. The two are bound together
625  *      and initialised. The socket is then returned. If we are out of inodes
626  *      NULL is returned. This functions uses GFP_KERNEL internally.
627  */
628 
629 struct socket *sock_alloc(void)
630 {
631         struct inode *inode;
632         struct socket *sock;
633 
634         inode = new_inode_pseudo(sock_mnt->mnt_sb);
635         if (!inode)
636                 return NULL;
637 
638         sock = SOCKET_I(inode);
639 
640         inode->i_ino = get_next_ino();
641         inode->i_mode = S_IFSOCK | S_IRWXUGO;
642         inode->i_uid = current_fsuid();
643         inode->i_gid = current_fsgid();
644         inode->i_op = &sockfs_inode_ops;
645 
646         return sock;
647 }
648 EXPORT_SYMBOL(sock_alloc);
649 
650 static void __sock_release(struct socket *sock, struct inode *inode)
651 {
652         const struct proto_ops *ops = READ_ONCE(sock->ops);
653 
654         if (ops) {
655                 struct module *owner = ops->owner;
656 
657                 if (inode)
658                         inode_lock(inode);
659                 ops->release(sock);
660                 sock->sk = NULL;
661                 if (inode)
662                         inode_unlock(inode);
663                 sock->ops = NULL;
664                 module_put(owner);
665         }
666 
667         if (sock->wq.fasync_list)
668                 pr_err("%s: fasync list not empty!\n", __func__);
669 
670         if (!sock->file) {
671                 iput(SOCK_INODE(sock));
672                 return;
673         }
674         sock->file = NULL;
675 }
676 
677 /**
678  *      sock_release - close a socket
679  *      @sock: socket to close
680  *
681  *      The socket is released from the protocol stack if it has a release
682  *      callback, and the inode is then released if the socket is bound to
683  *      an inode not a file.
684  */
685 void sock_release(struct socket *sock)
686 {
687         __sock_release(sock, NULL);
688 }
689 EXPORT_SYMBOL(sock_release);
690 
691 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
692 {
693         u8 flags = *tx_flags;
694 
695         if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE) {
696                 flags |= SKBTX_HW_TSTAMP;
697 
698                 /* PTP hardware clocks can provide a free running cycle counter
699                  * as a time base for virtual clocks. Tell driver to use the
700                  * free running cycle counter for timestamp if socket is bound
701                  * to virtual clock.
702                  */
703                 if (tsflags & SOF_TIMESTAMPING_BIND_PHC)
704                         flags |= SKBTX_HW_TSTAMP_USE_CYCLES;
705         }
706 
707         if (tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)
708                 flags |= SKBTX_SW_TSTAMP;
709 
710         if (tsflags & SOF_TIMESTAMPING_TX_SCHED)
711                 flags |= SKBTX_SCHED_TSTAMP;
712 
713         *tx_flags = flags;
714 }
715 EXPORT_SYMBOL(__sock_tx_timestamp);
716 
717 INDIRECT_CALLABLE_DECLARE(int inet_sendmsg(struct socket *, struct msghdr *,
718                                            size_t));
719 INDIRECT_CALLABLE_DECLARE(int inet6_sendmsg(struct socket *, struct msghdr *,
720                                             size_t));
721 
722 static noinline void call_trace_sock_send_length(struct sock *sk, int ret,
723                                                  int flags)
724 {
725         trace_sock_send_length(sk, ret, 0);
726 }
727 
728 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
729 {
730         int ret = INDIRECT_CALL_INET(READ_ONCE(sock->ops)->sendmsg, inet6_sendmsg,
731                                      inet_sendmsg, sock, msg,
732                                      msg_data_left(msg));
733         BUG_ON(ret == -EIOCBQUEUED);
734 
735         if (trace_sock_send_length_enabled())
736                 call_trace_sock_send_length(sock->sk, ret, 0);
737         return ret;
738 }
739 
740 static int __sock_sendmsg(struct socket *sock, struct msghdr *msg)
741 {
742         int err = security_socket_sendmsg(sock, msg,
743                                           msg_data_left(msg));
744 
745         return err ?: sock_sendmsg_nosec(sock, msg);
746 }
747 
748 /**
749  *      sock_sendmsg - send a message through @sock
750  *      @sock: socket
751  *      @msg: message to send
752  *
753  *      Sends @msg through @sock, passing through LSM.
754  *      Returns the number of bytes sent, or an error code.
755  */
756 int sock_sendmsg(struct socket *sock, struct msghdr *msg)
757 {
758         struct sockaddr_storage *save_addr = (struct sockaddr_storage *)msg->msg_name;
759         struct sockaddr_storage address;
760         int save_len = msg->msg_namelen;
761         int ret;
762 
763         if (msg->msg_name) {
764                 memcpy(&address, msg->msg_name, msg->msg_namelen);
765                 msg->msg_name = &address;
766         }
767 
768         ret = __sock_sendmsg(sock, msg);
769         msg->msg_name = save_addr;
770         msg->msg_namelen = save_len;
771 
772         return ret;
773 }
774 EXPORT_SYMBOL(sock_sendmsg);
775 
776 /**
777  *      kernel_sendmsg - send a message through @sock (kernel-space)
778  *      @sock: socket
779  *      @msg: message header
780  *      @vec: kernel vec
781  *      @num: vec array length
782  *      @size: total message data size
783  *
784  *      Builds the message data with @vec and sends it through @sock.
785  *      Returns the number of bytes sent, or an error code.
786  */
787 
788 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
789                    struct kvec *vec, size_t num, size_t size)
790 {
791         iov_iter_kvec(&msg->msg_iter, ITER_SOURCE, vec, num, size);
792         return sock_sendmsg(sock, msg);
793 }
794 EXPORT_SYMBOL(kernel_sendmsg);
795 
796 /**
797  *      kernel_sendmsg_locked - send a message through @sock (kernel-space)
798  *      @sk: sock
799  *      @msg: message header
800  *      @vec: output s/g array
801  *      @num: output s/g array length
802  *      @size: total message data size
803  *
804  *      Builds the message data with @vec and sends it through @sock.
805  *      Returns the number of bytes sent, or an error code.
806  *      Caller must hold @sk.
807  */
808 
809 int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
810                           struct kvec *vec, size_t num, size_t size)
811 {
812         struct socket *sock = sk->sk_socket;
813         const struct proto_ops *ops = READ_ONCE(sock->ops);
814 
815         if (!ops->sendmsg_locked)
816                 return sock_no_sendmsg_locked(sk, msg, size);
817 
818         iov_iter_kvec(&msg->msg_iter, ITER_SOURCE, vec, num, size);
819 
820         return ops->sendmsg_locked(sk, msg, msg_data_left(msg));
821 }
822 EXPORT_SYMBOL(kernel_sendmsg_locked);
823 
824 static bool skb_is_err_queue(const struct sk_buff *skb)
825 {
826         /* pkt_type of skbs enqueued on the error queue are set to
827          * PACKET_OUTGOING in skb_set_err_queue(). This is only safe to do
828          * in recvmsg, since skbs received on a local socket will never
829          * have a pkt_type of PACKET_OUTGOING.
830          */
831         return skb->pkt_type == PACKET_OUTGOING;
832 }
833 
834 /* On transmit, software and hardware timestamps are returned independently.
835  * As the two skb clones share the hardware timestamp, which may be updated
836  * before the software timestamp is received, a hardware TX timestamp may be
837  * returned only if there is no software TX timestamp. Ignore false software
838  * timestamps, which may be made in the __sock_recv_timestamp() call when the
839  * option SO_TIMESTAMP_OLD(NS) is enabled on the socket, even when the skb has a
840  * hardware timestamp.
841  */
842 static bool skb_is_swtx_tstamp(const struct sk_buff *skb, int false_tstamp)
843 {
844         return skb->tstamp && !false_tstamp && skb_is_err_queue(skb);
845 }
846 
847 static ktime_t get_timestamp(struct sock *sk, struct sk_buff *skb, int *if_index)
848 {
849         bool cycles = READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_BIND_PHC;
850         struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
851         struct net_device *orig_dev;
852         ktime_t hwtstamp;
853 
854         rcu_read_lock();
855         orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
856         if (orig_dev) {
857                 *if_index = orig_dev->ifindex;
858                 hwtstamp = netdev_get_tstamp(orig_dev, shhwtstamps, cycles);
859         } else {
860                 hwtstamp = shhwtstamps->hwtstamp;
861         }
862         rcu_read_unlock();
863 
864         return hwtstamp;
865 }
866 
867 static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb,
868                            int if_index)
869 {
870         struct scm_ts_pktinfo ts_pktinfo;
871         struct net_device *orig_dev;
872 
873         if (!skb_mac_header_was_set(skb))
874                 return;
875 
876         memset(&ts_pktinfo, 0, sizeof(ts_pktinfo));
877 
878         if (!if_index) {
879                 rcu_read_lock();
880                 orig_dev = dev_get_by_napi_id(skb_napi_id(skb));
881                 if (orig_dev)
882                         if_index = orig_dev->ifindex;
883                 rcu_read_unlock();
884         }
885         ts_pktinfo.if_index = if_index;
886 
887         ts_pktinfo.pkt_length = skb->len - skb_mac_offset(skb);
888         put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_PKTINFO,
889                  sizeof(ts_pktinfo), &ts_pktinfo);
890 }
891 
892 /*
893  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
894  */
895 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
896         struct sk_buff *skb)
897 {
898         int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
899         int new_tstamp = sock_flag(sk, SOCK_TSTAMP_NEW);
900         struct scm_timestamping_internal tss;
901         int empty = 1, false_tstamp = 0;
902         struct skb_shared_hwtstamps *shhwtstamps =
903                 skb_hwtstamps(skb);
904         int if_index;
905         ktime_t hwtstamp;
906         u32 tsflags;
907 
908         /* Race occurred between timestamp enabling and packet
909            receiving.  Fill in the current time for now. */
910         if (need_software_tstamp && skb->tstamp == 0) {
911                 __net_timestamp(skb);
912                 false_tstamp = 1;
913         }
914 
915         if (need_software_tstamp) {
916                 if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
917                         if (new_tstamp) {
918                                 struct __kernel_sock_timeval tv;
919 
920                                 skb_get_new_timestamp(skb, &tv);
921                                 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_NEW,
922                                          sizeof(tv), &tv);
923                         } else {
924                                 struct __kernel_old_timeval tv;
925 
926                                 skb_get_timestamp(skb, &tv);
927                                 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD,
928                                          sizeof(tv), &tv);
929                         }
930                 } else {
931                         if (new_tstamp) {
932                                 struct __kernel_timespec ts;
933 
934                                 skb_get_new_timestampns(skb, &ts);
935                                 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_NEW,
936                                          sizeof(ts), &ts);
937                         } else {
938                                 struct __kernel_old_timespec ts;
939 
940                                 skb_get_timestampns(skb, &ts);
941                                 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_OLD,
942                                          sizeof(ts), &ts);
943                         }
944                 }
945         }
946 
947         memset(&tss, 0, sizeof(tss));
948         tsflags = READ_ONCE(sk->sk_tsflags);
949         if ((tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
950             ktime_to_timespec64_cond(skb->tstamp, tss.ts + 0))
951                 empty = 0;
952         if (shhwtstamps &&
953             (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
954             !skb_is_swtx_tstamp(skb, false_tstamp)) {
955                 if_index = 0;
956                 if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP_NETDEV)
957                         hwtstamp = get_timestamp(sk, skb, &if_index);
958                 else
959                         hwtstamp = shhwtstamps->hwtstamp;
960 
961                 if (tsflags & SOF_TIMESTAMPING_BIND_PHC)
962                         hwtstamp = ptp_convert_timestamp(&hwtstamp,
963                                                          READ_ONCE(sk->sk_bind_phc));
964 
965                 if (ktime_to_timespec64_cond(hwtstamp, tss.ts + 2)) {
966                         empty = 0;
967 
968                         if ((tsflags & SOF_TIMESTAMPING_OPT_PKTINFO) &&
969                             !skb_is_err_queue(skb))
970                                 put_ts_pktinfo(msg, skb, if_index);
971                 }
972         }
973         if (!empty) {
974                 if (sock_flag(sk, SOCK_TSTAMP_NEW))
975                         put_cmsg_scm_timestamping64(msg, &tss);
976                 else
977                         put_cmsg_scm_timestamping(msg, &tss);
978 
979                 if (skb_is_err_queue(skb) && skb->len &&
980                     SKB_EXT_ERR(skb)->opt_stats)
981                         put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS,
982                                  skb->len, skb->data);
983         }
984 }
985 EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
986 
987 #ifdef CONFIG_WIRELESS
988 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
989         struct sk_buff *skb)
990 {
991         int ack;
992 
993         if (!sock_flag(sk, SOCK_WIFI_STATUS))
994                 return;
995         if (!skb->wifi_acked_valid)
996                 return;
997 
998         ack = skb->wifi_acked;
999 
1000         put_cmsg(msg, SOL_SOCKET, SCM_WIFI_STATUS, sizeof(ack), &ack);
1001 }
1002 EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
1003 #endif
1004 
1005 static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
1006                                    struct sk_buff *skb)
1007 {
1008         if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
1009                 put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
1010                         sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
1011 }
1012 
1013 static void sock_recv_mark(struct msghdr *msg, struct sock *sk,
1014                            struct sk_buff *skb)
1015 {
1016         if (sock_flag(sk, SOCK_RCVMARK) && skb) {
1017                 /* We must use a bounce buffer for CONFIG_HARDENED_USERCOPY=y */
1018                 __u32 mark = skb->mark;
1019 
1020                 put_cmsg(msg, SOL_SOCKET, SO_MARK, sizeof(__u32), &mark);
1021         }
1022 }
1023 
1024 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
1025                        struct sk_buff *skb)
1026 {
1027         sock_recv_timestamp(msg, sk, skb);
1028         sock_recv_drops(msg, sk, skb);
1029         sock_recv_mark(msg, sk, skb);
1030 }
1031 EXPORT_SYMBOL_GPL(__sock_recv_cmsgs);
1032 
1033 INDIRECT_CALLABLE_DECLARE(int inet_recvmsg(struct socket *, struct msghdr *,
1034                                            size_t, int));
1035 INDIRECT_CALLABLE_DECLARE(int inet6_recvmsg(struct socket *, struct msghdr *,
1036                                             size_t, int));
1037 
1038 static noinline void call_trace_sock_recv_length(struct sock *sk, int ret, int flags)
1039 {
1040         trace_sock_recv_length(sk, ret, flags);
1041 }
1042 
1043 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
1044                                      int flags)
1045 {
1046         int ret = INDIRECT_CALL_INET(READ_ONCE(sock->ops)->recvmsg,
1047                                      inet6_recvmsg,
1048                                      inet_recvmsg, sock, msg,
1049                                      msg_data_left(msg), flags);
1050         if (trace_sock_recv_length_enabled())
1051                 call_trace_sock_recv_length(sock->sk, ret, flags);
1052         return ret;
1053 }
1054 
1055 /**
1056  *      sock_recvmsg - receive a message from @sock
1057  *      @sock: socket
1058  *      @msg: message to receive
1059  *      @flags: message flags
1060  *
1061  *      Receives @msg from @sock, passing through LSM. Returns the total number
1062  *      of bytes received, or an error.
1063  */
1064 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
1065 {
1066         int err = security_socket_recvmsg(sock, msg, msg_data_left(msg), flags);
1067 
1068         return err ?: sock_recvmsg_nosec(sock, msg, flags);
1069 }
1070 EXPORT_SYMBOL(sock_recvmsg);
1071 
1072 /**
1073  *      kernel_recvmsg - Receive a message from a socket (kernel space)
1074  *      @sock: The socket to receive the message from
1075  *      @msg: Received message
1076  *      @vec: Input s/g array for message data
1077  *      @num: Size of input s/g array
1078  *      @size: Number of bytes to read
1079  *      @flags: Message flags (MSG_DONTWAIT, etc...)
1080  *
1081  *      On return the msg structure contains the scatter/gather array passed in the
1082  *      vec argument. The array is modified so that it consists of the unfilled
1083  *      portion of the original array.
1084  *
1085  *      The returned value is the total number of bytes received, or an error.
1086  */
1087 
1088 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
1089                    struct kvec *vec, size_t num, size_t size, int flags)
1090 {
1091         msg->msg_control_is_user = false;
1092         iov_iter_kvec(&msg->msg_iter, ITER_DEST, vec, num, size);
1093         return sock_recvmsg(sock, msg, flags);
1094 }
1095 EXPORT_SYMBOL(kernel_recvmsg);
1096 
1097 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
1098                                 struct pipe_inode_info *pipe, size_t len,
1099                                 unsigned int flags)
1100 {
1101         struct socket *sock = file->private_data;
1102         const struct proto_ops *ops;
1103 
1104         ops = READ_ONCE(sock->ops);
1105         if (unlikely(!ops->splice_read))
1106                 return copy_splice_read(file, ppos, pipe, len, flags);
1107 
1108         return ops->splice_read(sock, ppos, pipe, len, flags);
1109 }
1110 
1111 static void sock_splice_eof(struct file *file)
1112 {
1113         struct socket *sock = file->private_data;
1114         const struct proto_ops *ops;
1115 
1116         ops = READ_ONCE(sock->ops);
1117         if (ops->splice_eof)
1118                 ops->splice_eof(sock);
1119 }
1120 
1121 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
1122 {
1123         struct file *file = iocb->ki_filp;
1124         struct socket *sock = file->private_data;
1125         struct msghdr msg = {.msg_iter = *to,
1126                              .msg_iocb = iocb};
1127         ssize_t res;
1128 
1129         if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT))
1130                 msg.msg_flags = MSG_DONTWAIT;
1131 
1132         if (iocb->ki_pos != 0)
1133                 return -ESPIPE;
1134 
1135         if (!iov_iter_count(to))        /* Match SYS5 behaviour */
1136                 return 0;
1137 
1138         res = sock_recvmsg(sock, &msg, msg.msg_flags);
1139         *to = msg.msg_iter;
1140         return res;
1141 }
1142 
1143 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
1144 {
1145         struct file *file = iocb->ki_filp;
1146         struct socket *sock = file->private_data;
1147         struct msghdr msg = {.msg_iter = *from,
1148                              .msg_iocb = iocb};
1149         ssize_t res;
1150 
1151         if (iocb->ki_pos != 0)
1152                 return -ESPIPE;
1153 
1154         if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT))
1155                 msg.msg_flags = MSG_DONTWAIT;
1156 
1157         if (sock->type == SOCK_SEQPACKET)
1158                 msg.msg_flags |= MSG_EOR;
1159 
1160         res = __sock_sendmsg(sock, &msg);
1161         *from = msg.msg_iter;
1162         return res;
1163 }
1164 
1165 /*
1166  * Atomic setting of ioctl hooks to avoid race
1167  * with module unload.
1168  */
1169 
1170 static DEFINE_MUTEX(br_ioctl_mutex);
1171 static int (*br_ioctl_hook)(struct net *net, struct net_bridge *br,
1172                             unsigned int cmd, struct ifreq *ifr,
1173                             void __user *uarg);
1174 
1175 void brioctl_set(int (*hook)(struct net *net, struct net_bridge *br,
1176                              unsigned int cmd, struct ifreq *ifr,
1177                              void __user *uarg))
1178 {
1179         mutex_lock(&br_ioctl_mutex);
1180         br_ioctl_hook = hook;
1181         mutex_unlock(&br_ioctl_mutex);
1182 }
1183 EXPORT_SYMBOL(brioctl_set);
1184 
1185 int br_ioctl_call(struct net *net, struct net_bridge *br, unsigned int cmd,
1186                   struct ifreq *ifr, void __user *uarg)
1187 {
1188         int err = -ENOPKG;
1189 
1190         if (!br_ioctl_hook)
1191                 request_module("bridge");
1192 
1193         mutex_lock(&br_ioctl_mutex);
1194         if (br_ioctl_hook)
1195                 err = br_ioctl_hook(net, br, cmd, ifr, uarg);
1196         mutex_unlock(&br_ioctl_mutex);
1197 
1198         return err;
1199 }
1200 
1201 static DEFINE_MUTEX(vlan_ioctl_mutex);
1202 static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
1203 
1204 void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
1205 {
1206         mutex_lock(&vlan_ioctl_mutex);
1207         vlan_ioctl_hook = hook;
1208         mutex_unlock(&vlan_ioctl_mutex);
1209 }
1210 EXPORT_SYMBOL(vlan_ioctl_set);
1211 
1212 static long sock_do_ioctl(struct net *net, struct socket *sock,
1213                           unsigned int cmd, unsigned long arg)
1214 {
1215         const struct proto_ops *ops = READ_ONCE(sock->ops);
1216         struct ifreq ifr;
1217         bool need_copyout;
1218         int err;
1219         void __user *argp = (void __user *)arg;
1220         void __user *data;
1221 
1222         err = ops->ioctl(sock, cmd, arg);
1223 
1224         /*
1225          * If this ioctl is unknown try to hand it down
1226          * to the NIC driver.
1227          */
1228         if (err != -ENOIOCTLCMD)
1229                 return err;
1230 
1231         if (!is_socket_ioctl_cmd(cmd))
1232                 return -ENOTTY;
1233 
1234         if (get_user_ifreq(&ifr, &data, argp))
1235                 return -EFAULT;
1236         err = dev_ioctl(net, cmd, &ifr, data, &need_copyout);
1237         if (!err && need_copyout)
1238                 if (put_user_ifreq(&ifr, argp))
1239                         return -EFAULT;
1240 
1241         return err;
1242 }
1243 
1244 /*
1245  *      With an ioctl, arg may well be a user mode pointer, but we don't know
1246  *      what to do with it - that's up to the protocol still.
1247  */
1248 
1249 static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
1250 {
1251         const struct proto_ops  *ops;
1252         struct socket *sock;
1253         struct sock *sk;
1254         void __user *argp = (void __user *)arg;
1255         int pid, err;
1256         struct net *net;
1257 
1258         sock = file->private_data;
1259         ops = READ_ONCE(sock->ops);
1260         sk = sock->sk;
1261         net = sock_net(sk);
1262         if (unlikely(cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))) {
1263                 struct ifreq ifr;
1264                 void __user *data;
1265                 bool need_copyout;
1266                 if (get_user_ifreq(&ifr, &data, argp))
1267                         return -EFAULT;
1268                 err = dev_ioctl(net, cmd, &ifr, data, &need_copyout);
1269                 if (!err && need_copyout)
1270                         if (put_user_ifreq(&ifr, argp))
1271                                 return -EFAULT;
1272         } else
1273 #ifdef CONFIG_WEXT_CORE
1274         if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
1275                 err = wext_handle_ioctl(net, cmd, argp);
1276         } else
1277 #endif
1278                 switch (cmd) {
1279                 case FIOSETOWN:
1280                 case SIOCSPGRP:
1281                         err = -EFAULT;
1282                         if (get_user(pid, (int __user *)argp))
1283                                 break;
1284                         err = f_setown(sock->file, pid, 1);
1285                         break;
1286                 case FIOGETOWN:
1287                 case SIOCGPGRP:
1288                         err = put_user(f_getown(sock->file),
1289                                        (int __user *)argp);
1290                         break;
1291                 case SIOCGIFBR:
1292                 case SIOCSIFBR:
1293                 case SIOCBRADDBR:
1294                 case SIOCBRDELBR:
1295                         err = br_ioctl_call(net, NULL, cmd, NULL, argp);
1296                         break;
1297                 case SIOCGIFVLAN:
1298                 case SIOCSIFVLAN:
1299                         err = -ENOPKG;
1300                         if (!vlan_ioctl_hook)
1301                                 request_module("8021q");
1302 
1303                         mutex_lock(&vlan_ioctl_mutex);
1304                         if (vlan_ioctl_hook)
1305                                 err = vlan_ioctl_hook(net, argp);
1306                         mutex_unlock(&vlan_ioctl_mutex);
1307                         break;
1308                 case SIOCGSKNS:
1309                         err = -EPERM;
1310                         if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1311                                 break;
1312 
1313                         err = open_related_ns(&net->ns, get_net_ns);
1314                         break;
1315                 case SIOCGSTAMP_OLD:
1316                 case SIOCGSTAMPNS_OLD:
1317                         if (!ops->gettstamp) {
1318                                 err = -ENOIOCTLCMD;
1319                                 break;
1320                         }
1321                         err = ops->gettstamp(sock, argp,
1322                                              cmd == SIOCGSTAMP_OLD,
1323                                              !IS_ENABLED(CONFIG_64BIT));
1324                         break;
1325                 case SIOCGSTAMP_NEW:
1326                 case SIOCGSTAMPNS_NEW:
1327                         if (!ops->gettstamp) {
1328                                 err = -ENOIOCTLCMD;
1329                                 break;
1330                         }
1331                         err = ops->gettstamp(sock, argp,
1332                                              cmd == SIOCGSTAMP_NEW,
1333                                              false);
1334                         break;
1335 
1336                 case SIOCGIFCONF:
1337                         err = dev_ifconf(net, argp);
1338                         break;
1339 
1340                 default:
1341                         err = sock_do_ioctl(net, sock, cmd, arg);
1342                         break;
1343                 }
1344         return err;
1345 }
1346 
1347 /**
1348  *      sock_create_lite - creates a socket
1349  *      @family: protocol family (AF_INET, ...)
1350  *      @type: communication type (SOCK_STREAM, ...)
1351  *      @protocol: protocol (0, ...)
1352  *      @res: new socket
1353  *
1354  *      Creates a new socket and assigns it to @res, passing through LSM.
1355  *      The new socket initialization is not complete, see kernel_accept().
1356  *      Returns 0 or an error. On failure @res is set to %NULL.
1357  *      This function internally uses GFP_KERNEL.
1358  */
1359 
1360 int sock_create_lite(int family, int type, int protocol, struct socket **res)
1361 {
1362         int err;
1363         struct socket *sock = NULL;
1364 
1365         err = security_socket_create(family, type, protocol, 1);
1366         if (err)
1367                 goto out;
1368 
1369         sock = sock_alloc();
1370         if (!sock) {
1371                 err = -ENOMEM;
1372                 goto out;
1373         }
1374 
1375         sock->type = type;
1376         err = security_socket_post_create(sock, family, type, protocol, 1);
1377         if (err)
1378                 goto out_release;
1379 
1380 out:
1381         *res = sock;
1382         return err;
1383 out_release:
1384         sock_release(sock);
1385         sock = NULL;
1386         goto out;
1387 }
1388 EXPORT_SYMBOL(sock_create_lite);
1389 
1390 /* No kernel lock held - perfect */
1391 static __poll_t sock_poll(struct file *file, poll_table *wait)
1392 {
1393         struct socket *sock = file->private_data;
1394         const struct proto_ops *ops = READ_ONCE(sock->ops);
1395         __poll_t events = poll_requested_events(wait), flag = 0;
1396 
1397         if (!ops->poll)
1398                 return 0;
1399 
1400         if (sk_can_busy_loop(sock->sk)) {
1401                 /* poll once if requested by the syscall */
1402                 if (events & POLL_BUSY_LOOP)
1403                         sk_busy_loop(sock->sk, 1);
1404 
1405                 /* if this socket can poll_ll, tell the system call */
1406                 flag = POLL_BUSY_LOOP;
1407         }
1408 
1409         return ops->poll(file, sock, wait) | flag;
1410 }
1411 
1412 static int sock_mmap(struct file *file, struct vm_area_struct *vma)
1413 {
1414         struct socket *sock = file->private_data;
1415 
1416         return READ_ONCE(sock->ops)->mmap(file, sock, vma);
1417 }
1418 
1419 static int sock_close(struct inode *inode, struct file *filp)
1420 {
1421         __sock_release(SOCKET_I(inode), inode);
1422         return 0;
1423 }
1424 
1425 /*
1426  *      Update the socket async list
1427  *
1428  *      Fasync_list locking strategy.
1429  *
1430  *      1. fasync_list is modified only under process context socket lock
1431  *         i.e. under semaphore.
1432  *      2. fasync_list is used under read_lock(&sk->sk_callback_lock)
1433  *         or under socket lock
1434  */
1435 
1436 static int sock_fasync(int fd, struct file *filp, int on)
1437 {
1438         struct socket *sock = filp->private_data;
1439         struct sock *sk = sock->sk;
1440         struct socket_wq *wq = &sock->wq;
1441 
1442         if (sk == NULL)
1443                 return -EINVAL;
1444 
1445         lock_sock(sk);
1446         fasync_helper(fd, filp, on, &wq->fasync_list);
1447 
1448         if (!wq->fasync_list)
1449                 sock_reset_flag(sk, SOCK_FASYNC);
1450         else
1451                 sock_set_flag(sk, SOCK_FASYNC);
1452 
1453         release_sock(sk);
1454         return 0;
1455 }
1456 
1457 /* This function may be called only under rcu_lock */
1458 
1459 int sock_wake_async(struct socket_wq *wq, int how, int band)
1460 {
1461         if (!wq || !wq->fasync_list)
1462                 return -1;
1463 
1464         switch (how) {
1465         case SOCK_WAKE_WAITD:
1466                 if (test_bit(SOCKWQ_ASYNC_WAITDATA, &wq->flags))
1467                         break;
1468                 goto call_kill;
1469         case SOCK_WAKE_SPACE:
1470                 if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags))
1471                         break;
1472                 fallthrough;
1473         case SOCK_WAKE_IO:
1474 call_kill:
1475                 kill_fasync(&wq->fasync_list, SIGIO, band);
1476                 break;
1477         case SOCK_WAKE_URG:
1478                 kill_fasync(&wq->fasync_list, SIGURG, band);
1479         }
1480 
1481         return 0;
1482 }
1483 EXPORT_SYMBOL(sock_wake_async);
1484 
1485 /**
1486  *      __sock_create - creates a socket
1487  *      @net: net namespace
1488  *      @family: protocol family (AF_INET, ...)
1489  *      @type: communication type (SOCK_STREAM, ...)
1490  *      @protocol: protocol (0, ...)
1491  *      @res: new socket
1492  *      @kern: boolean for kernel space sockets
1493  *
1494  *      Creates a new socket and assigns it to @res, passing through LSM.
1495  *      Returns 0 or an error. On failure @res is set to %NULL. @kern must
1496  *      be set to true if the socket resides in kernel space.
1497  *      This function internally uses GFP_KERNEL.
1498  */
1499 
1500 int __sock_create(struct net *net, int family, int type, int protocol,
1501                          struct socket **res, int kern)
1502 {
1503         int err;
1504         struct socket *sock;
1505         const struct net_proto_family *pf;
1506 
1507         /*
1508          *      Check protocol is in range
1509          */
1510         if (family < 0 || family >= NPROTO)
1511                 return -EAFNOSUPPORT;
1512         if (type < 0 || type >= SOCK_MAX)
1513                 return -EINVAL;
1514 
1515         /* Compatibility.
1516 
1517            This uglymoron is moved from INET layer to here to avoid
1518            deadlock in module load.
1519          */
1520         if (family == PF_INET && type == SOCK_PACKET) {
1521                 pr_info_once("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
1522                              current->comm);
1523                 family = PF_PACKET;
1524         }
1525 
1526         err = security_socket_create(family, type, protocol, kern);
1527         if (err)
1528                 return err;
1529 
1530         /*
1531          *      Allocate the socket and allow the family to set things up. if
1532          *      the protocol is 0, the family is instructed to select an appropriate
1533          *      default.
1534          */
1535         sock = sock_alloc();
1536         if (!sock) {
1537                 net_warn_ratelimited("socket: no more sockets\n");
1538                 return -ENFILE; /* Not exactly a match, but its the
1539                                    closest posix thing */
1540         }
1541 
1542         sock->type = type;
1543 
1544 #ifdef CONFIG_MODULES
1545         /* Attempt to load a protocol module if the find failed.
1546          *
1547          * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
1548          * requested real, full-featured networking support upon configuration.
1549          * Otherwise module support will break!
1550          */
1551         if (rcu_access_pointer(net_families[family]) == NULL)
1552                 request_module("net-pf-%d", family);
1553 #endif
1554 
1555         rcu_read_lock();
1556         pf = rcu_dereference(net_families[family]);
1557         err = -EAFNOSUPPORT;
1558         if (!pf)
1559                 goto out_release;
1560 
1561         /*
1562          * We will call the ->create function, that possibly is in a loadable
1563          * module, so we have to bump that loadable module refcnt first.
1564          */
1565         if (!try_module_get(pf->owner))
1566                 goto out_release;
1567 
1568         /* Now protected by module ref count */
1569         rcu_read_unlock();
1570 
1571         err = pf->create(net, sock, protocol, kern);
1572         if (err < 0) {
1573                 /* ->create should release the allocated sock->sk object on error
1574                  * but it may leave the dangling pointer
1575                  */
1576                 sock->sk = NULL;
1577                 goto out_module_put;
1578         }
1579 
1580         /*
1581          * Now to bump the refcnt of the [loadable] module that owns this
1582          * socket at sock_release time we decrement its refcnt.
1583          */
1584         if (!try_module_get(sock->ops->owner))
1585                 goto out_module_busy;
1586 
1587         /*
1588          * Now that we're done with the ->create function, the [loadable]
1589          * module can have its refcnt decremented
1590          */
1591         module_put(pf->owner);
1592         err = security_socket_post_create(sock, family, type, protocol, kern);
1593         if (err)
1594                 goto out_sock_release;
1595         *res = sock;
1596 
1597         return 0;
1598 
1599 out_module_busy:
1600         err = -EAFNOSUPPORT;
1601 out_module_put:
1602         sock->ops = NULL;
1603         module_put(pf->owner);
1604 out_sock_release:
1605         sock_release(sock);
1606         return err;
1607 
1608 out_release:
1609         rcu_read_unlock();
1610         goto out_sock_release;
1611 }
1612 EXPORT_SYMBOL(__sock_create);
1613 
1614 /**
1615  *      sock_create - creates a socket
1616  *      @family: protocol family (AF_INET, ...)
1617  *      @type: communication type (SOCK_STREAM, ...)
1618  *      @protocol: protocol (0, ...)
1619  *      @res: new socket
1620  *
1621  *      A wrapper around __sock_create().
1622  *      Returns 0 or an error. This function internally uses GFP_KERNEL.
1623  */
1624 
1625 int sock_create(int family, int type, int protocol, struct socket **res)
1626 {
1627         return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
1628 }
1629 EXPORT_SYMBOL(sock_create);
1630 
1631 /**
1632  *      sock_create_kern - creates a socket (kernel space)
1633  *      @net: net namespace
1634  *      @family: protocol family (AF_INET, ...)
1635  *      @type: communication type (SOCK_STREAM, ...)
1636  *      @protocol: protocol (0, ...)
1637  *      @res: new socket
1638  *
1639  *      A wrapper around __sock_create().
1640  *      Returns 0 or an error. This function internally uses GFP_KERNEL.
1641  */
1642 
1643 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
1644 {
1645         return __sock_create(net, family, type, protocol, res, 1);
1646 }
1647 EXPORT_SYMBOL(sock_create_kern);
1648 
1649 static struct socket *__sys_socket_create(int family, int type, int protocol)
1650 {
1651         struct socket *sock;
1652         int retval;
1653 
1654         /* Check the SOCK_* constants for consistency.  */
1655         BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
1656         BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
1657         BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
1658         BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
1659 
1660         if ((type & ~SOCK_TYPE_MASK) & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1661                 return ERR_PTR(-EINVAL);
1662         type &= SOCK_TYPE_MASK;
1663 
1664         retval = sock_create(family, type, protocol, &sock);
1665         if (retval < 0)
1666                 return ERR_PTR(retval);
1667 
1668         return sock;
1669 }
1670 
1671 struct file *__sys_socket_file(int family, int type, int protocol)
1672 {
1673         struct socket *sock;
1674         int flags;
1675 
1676         sock = __sys_socket_create(family, type, protocol);
1677         if (IS_ERR(sock))
1678                 return ERR_CAST(sock);
1679 
1680         flags = type & ~SOCK_TYPE_MASK;
1681         if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1682                 flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1683 
1684         return sock_alloc_file(sock, flags, NULL);
1685 }
1686 
1687 /*      A hook for bpf progs to attach to and update socket protocol.
1688  *
1689  *      A static noinline declaration here could cause the compiler to
1690  *      optimize away the function. A global noinline declaration will
1691  *      keep the definition, but may optimize away the callsite.
1692  *      Therefore, __weak is needed to ensure that the call is still
1693  *      emitted, by telling the compiler that we don't know what the
1694  *      function might eventually be.
1695  */
1696 
1697 __bpf_hook_start();
1698 
1699 __weak noinline int update_socket_protocol(int family, int type, int protocol)
1700 {
1701         return protocol;
1702 }
1703 
1704 __bpf_hook_end();
1705 
1706 int __sys_socket(int family, int type, int protocol)
1707 {
1708         struct socket *sock;
1709         int flags;
1710 
1711         sock = __sys_socket_create(family, type,
1712                                    update_socket_protocol(family, type, protocol));
1713         if (IS_ERR(sock))
1714                 return PTR_ERR(sock);
1715 
1716         flags = type & ~SOCK_TYPE_MASK;
1717         if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1718                 flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1719 
1720         return sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
1721 }
1722 
1723 SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
1724 {
1725         return __sys_socket(family, type, protocol);
1726 }
1727 
1728 /*
1729  *      Create a pair of connected sockets.
1730  */
1731 
1732 int __sys_socketpair(int family, int type, int protocol, int __user *usockvec)
1733 {
1734         struct socket *sock1, *sock2;
1735         int fd1, fd2, err;
1736         struct file *newfile1, *newfile2;
1737         int flags;
1738 
1739         flags = type & ~SOCK_TYPE_MASK;
1740         if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1741                 return -EINVAL;
1742         type &= SOCK_TYPE_MASK;
1743 
1744         if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1745                 flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1746 
1747         /*
1748          * reserve descriptors and make sure we won't fail
1749          * to return them to userland.
1750          */
1751         fd1 = get_unused_fd_flags(flags);
1752         if (unlikely(fd1 < 0))
1753                 return fd1;
1754 
1755         fd2 = get_unused_fd_flags(flags);
1756         if (unlikely(fd2 < 0)) {
1757                 put_unused_fd(fd1);
1758                 return fd2;
1759         }
1760 
1761         err = put_user(fd1, &usockvec[0]);
1762         if (err)
1763                 goto out;
1764 
1765         err = put_user(fd2, &usockvec[1]);
1766         if (err)
1767                 goto out;
1768 
1769         /*
1770          * Obtain the first socket and check if the underlying protocol
1771          * supports the socketpair call.
1772          */
1773 
1774         err = sock_create(family, type, protocol, &sock1);
1775         if (unlikely(err < 0))
1776                 goto out;
1777 
1778         err = sock_create(family, type, protocol, &sock2);
1779         if (unlikely(err < 0)) {
1780                 sock_release(sock1);
1781                 goto out;
1782         }
1783 
1784         err = security_socket_socketpair(sock1, sock2);
1785         if (unlikely(err)) {
1786                 sock_release(sock2);
1787                 sock_release(sock1);
1788                 goto out;
1789         }
1790 
1791         err = READ_ONCE(sock1->ops)->socketpair(sock1, sock2);
1792         if (unlikely(err < 0)) {
1793                 sock_release(sock2);
1794                 sock_release(sock1);
1795                 goto out;
1796         }
1797 
1798         newfile1 = sock_alloc_file(sock1, flags, NULL);
1799         if (IS_ERR(newfile1)) {
1800                 err = PTR_ERR(newfile1);
1801                 sock_release(sock2);
1802                 goto out;
1803         }
1804 
1805         newfile2 = sock_alloc_file(sock2, flags, NULL);
1806         if (IS_ERR(newfile2)) {
1807                 err = PTR_ERR(newfile2);
1808                 fput(newfile1);
1809                 goto out;
1810         }
1811 
1812         audit_fd_pair(fd1, fd2);
1813 
1814         fd_install(fd1, newfile1);
1815         fd_install(fd2, newfile2);
1816         return 0;
1817 
1818 out:
1819         put_unused_fd(fd2);
1820         put_unused_fd(fd1);
1821         return err;
1822 }
1823 
1824 SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
1825                 int __user *, usockvec)
1826 {
1827         return __sys_socketpair(family, type, protocol, usockvec);
1828 }
1829 
1830 int __sys_bind_socket(struct socket *sock, struct sockaddr_storage *address,
1831                       int addrlen)
1832 {
1833         int err;
1834 
1835         err = security_socket_bind(sock, (struct sockaddr *)address,
1836                                    addrlen);
1837         if (!err)
1838                 err = READ_ONCE(sock->ops)->bind(sock,
1839                                                  (struct sockaddr *)address,
1840                                                  addrlen);
1841         return err;
1842 }
1843 
1844 /*
1845  *      Bind a name to a socket. Nothing much to do here since it's
1846  *      the protocol's responsibility to handle the local address.
1847  *
1848  *      We move the socket address to kernel space before we call
1849  *      the protocol layer (having also checked the address is ok).
1850  */
1851 
1852 int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
1853 {
1854         struct socket *sock;
1855         struct sockaddr_storage address;
1856         int err, fput_needed;
1857 
1858         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1859         if (sock) {
1860                 err = move_addr_to_kernel(umyaddr, addrlen, &address);
1861                 if (!err)
1862                         err = __sys_bind_socket(sock, &address, addrlen);
1863                 fput_light(sock->file, fput_needed);
1864         }
1865         return err;
1866 }
1867 
1868 SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
1869 {
1870         return __sys_bind(fd, umyaddr, addrlen);
1871 }
1872 
1873 /*
1874  *      Perform a listen. Basically, we allow the protocol to do anything
1875  *      necessary for a listen, and if that works, we mark the socket as
1876  *      ready for listening.
1877  */
1878 int __sys_listen_socket(struct socket *sock, int backlog)
1879 {
1880         int somaxconn, err;
1881 
1882         somaxconn = READ_ONCE(sock_net(sock->sk)->core.sysctl_somaxconn);
1883         if ((unsigned int)backlog > somaxconn)
1884                 backlog = somaxconn;
1885 
1886         err = security_socket_listen(sock, backlog);
1887         if (!err)
1888                 err = READ_ONCE(sock->ops)->listen(sock, backlog);
1889         return err;
1890 }
1891 
1892 int __sys_listen(int fd, int backlog)
1893 {
1894         struct socket *sock;
1895         int err, fput_needed;
1896 
1897         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1898         if (sock) {
1899                 err = __sys_listen_socket(sock, backlog);
1900                 fput_light(sock->file, fput_needed);
1901         }
1902         return err;
1903 }
1904 
1905 SYSCALL_DEFINE2(listen, int, fd, int, backlog)
1906 {
1907         return __sys_listen(fd, backlog);
1908 }
1909 
1910 struct file *do_accept(struct file *file, struct proto_accept_arg *arg,
1911                        struct sockaddr __user *upeer_sockaddr,
1912                        int __user *upeer_addrlen, int flags)
1913 {
1914         struct socket *sock, *newsock;
1915         struct file *newfile;
1916         int err, len;
1917         struct sockaddr_storage address;
1918         const struct proto_ops *ops;
1919 
1920         sock = sock_from_file(file);
1921         if (!sock)
1922                 return ERR_PTR(-ENOTSOCK);
1923 
1924         newsock = sock_alloc();
1925         if (!newsock)
1926                 return ERR_PTR(-ENFILE);
1927         ops = READ_ONCE(sock->ops);
1928 
1929         newsock->type = sock->type;
1930         newsock->ops = ops;
1931 
1932         /*
1933          * We don't need try_module_get here, as the listening socket (sock)
1934          * has the protocol module (sock->ops->owner) held.
1935          */
1936         __module_get(ops->owner);
1937 
1938         newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);
1939         if (IS_ERR(newfile))
1940                 return newfile;
1941 
1942         err = security_socket_accept(sock, newsock);
1943         if (err)
1944                 goto out_fd;
1945 
1946         arg->flags |= sock->file->f_flags;
1947         err = ops->accept(sock, newsock, arg);
1948         if (err < 0)
1949                 goto out_fd;
1950 
1951         if (ccs_socket_post_accept_permission(sock, newsock)) {
1952                 err = -EAGAIN; /* Hope less harmful than -EPERM. */
1953                 goto out_fd;
1954         }
1955         if (upeer_sockaddr) {
1956                 len = ops->getname(newsock, (struct sockaddr *)&address, 2);
1957                 if (len < 0) {
1958                         err = -ECONNABORTED;
1959                         goto out_fd;
1960                 }
1961                 err = move_addr_to_user(&address,
1962                                         len, upeer_sockaddr, upeer_addrlen);
1963                 if (err < 0)
1964                         goto out_fd;
1965         }
1966 
1967         /* File flags are not inherited via accept() unlike another OSes. */
1968         return newfile;
1969 out_fd:
1970         fput(newfile);
1971         return ERR_PTR(err);
1972 }
1973 
1974 static int __sys_accept4_file(struct file *file, struct sockaddr __user *upeer_sockaddr,
1975                               int __user *upeer_addrlen, int flags)
1976 {
1977         struct proto_accept_arg arg = { };
1978         struct file *newfile;
1979         int newfd;
1980 
1981         if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1982                 return -EINVAL;
1983 
1984         if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1985                 flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1986 
1987         newfd = get_unused_fd_flags(flags);
1988         if (unlikely(newfd < 0))
1989                 return newfd;
1990 
1991         newfile = do_accept(file, &arg, upeer_sockaddr, upeer_addrlen,
1992                             flags);
1993         if (IS_ERR(newfile)) {
1994                 put_unused_fd(newfd);
1995                 return PTR_ERR(newfile);
1996         }
1997         fd_install(newfd, newfile);
1998         return newfd;
1999 }
2000 
2001 /*
2002  *      For accept, we attempt to create a new socket, set up the link
2003  *      with the client, wake up the client, then return the new
2004  *      connected fd. We collect the address of the connector in kernel
2005  *      space and move it to user at the very end. This is unclean because
2006  *      we open the socket then return an error.
2007  *
2008  *      1003.1g adds the ability to recvmsg() to query connection pending
2009  *      status to recvmsg. We need to add that support in a way thats
2010  *      clean when we restructure accept also.
2011  */
2012 
2013 int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
2014                   int __user *upeer_addrlen, int flags)
2015 {
2016         int ret = -EBADF;
2017         struct fd f;
2018 
2019         f = fdget(fd);
2020         if (f.file) {
2021                 ret = __sys_accept4_file(f.file, upeer_sockaddr,
2022                                          upeer_addrlen, flags);
2023                 fdput(f);
2024         }
2025 
2026         return ret;
2027 }
2028 
2029 SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
2030                 int __user *, upeer_addrlen, int, flags)
2031 {
2032         return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, flags);
2033 }
2034 
2035 SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
2036                 int __user *, upeer_addrlen)
2037 {
2038         return __sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
2039 }
2040 
2041 /*
2042  *      Attempt to connect to a socket with the server address.  The address
2043  *      is in user space so we verify it is OK and move it to kernel space.
2044  *
2045  *      For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
2046  *      break bindings
2047  *
2048  *      NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
2049  *      other SEQPACKET protocols that take time to connect() as it doesn't
2050  *      include the -EINPROGRESS status for such sockets.
2051  */
2052 
2053 int __sys_connect_file(struct file *file, struct sockaddr_storage *address,
2054                        int addrlen, int file_flags)
2055 {
2056         struct socket *sock;
2057         int err;
2058 
2059         sock = sock_from_file(file);
2060         if (!sock) {
2061                 err = -ENOTSOCK;
2062                 goto out;
2063         }
2064 
2065         err =
2066             security_socket_connect(sock, (struct sockaddr *)address, addrlen);
2067         if (err)
2068                 goto out;
2069 
2070         err = READ_ONCE(sock->ops)->connect(sock, (struct sockaddr *)address,
2071                                 addrlen, sock->file->f_flags | file_flags);
2072 out:
2073         return err;
2074 }
2075 
2076 int __sys_connect(int fd, struct sockaddr __user *uservaddr, int addrlen)
2077 {
2078         int ret = -EBADF;
2079         struct fd f;
2080 
2081         f = fdget(fd);
2082         if (f.file) {
2083                 struct sockaddr_storage address;
2084 
2085                 ret = move_addr_to_kernel(uservaddr, addrlen, &address);
2086                 if (!ret)
2087                         ret = __sys_connect_file(f.file, &address, addrlen, 0);
2088                 fdput(f);
2089         }
2090 
2091         return ret;
2092 }
2093 
2094 SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
2095                 int, addrlen)
2096 {
2097         return __sys_connect(fd, uservaddr, addrlen);
2098 }
2099 
2100 /*
2101  *      Get the local address ('name') of a socket object. Move the obtained
2102  *      name to user space.
2103  */
2104 
2105 int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
2106                       int __user *usockaddr_len)
2107 {
2108         struct socket *sock;
2109         struct sockaddr_storage address;
2110         int err, fput_needed;
2111 
2112         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2113         if (!sock)
2114                 goto out;
2115 
2116         err = security_socket_getsockname(sock);
2117         if (err)
2118                 goto out_put;
2119 
2120         err = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 0);
2121         if (err < 0)
2122                 goto out_put;
2123         /* "err" is actually length in this case */
2124         err = move_addr_to_user(&address, err, usockaddr, usockaddr_len);
2125 
2126 out_put:
2127         fput_light(sock->file, fput_needed);
2128 out:
2129         return err;
2130 }
2131 
2132 SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
2133                 int __user *, usockaddr_len)
2134 {
2135         return __sys_getsockname(fd, usockaddr, usockaddr_len);
2136 }
2137 
2138 /*
2139  *      Get the remote address ('name') of a socket object. Move the obtained
2140  *      name to user space.
2141  */
2142 
2143 int __sys_getpeername(int fd, struct sockaddr __user *usockaddr,
2144                       int __user *usockaddr_len)
2145 {
2146         struct socket *sock;
2147         struct sockaddr_storage address;
2148         int err, fput_needed;
2149 
2150         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2151         if (sock != NULL) {
2152                 const struct proto_ops *ops = READ_ONCE(sock->ops);
2153 
2154                 err = security_socket_getpeername(sock);
2155                 if (err) {
2156                         fput_light(sock->file, fput_needed);
2157                         return err;
2158                 }
2159 
2160                 err = ops->getname(sock, (struct sockaddr *)&address, 1);
2161                 if (err >= 0)
2162                         /* "err" is actually length in this case */
2163                         err = move_addr_to_user(&address, err, usockaddr,
2164                                                 usockaddr_len);
2165                 fput_light(sock->file, fput_needed);
2166         }
2167         return err;
2168 }
2169 
2170 SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
2171                 int __user *, usockaddr_len)
2172 {
2173         return __sys_getpeername(fd, usockaddr, usockaddr_len);
2174 }
2175 
2176 /*
2177  *      Send a datagram to a given address. We move the address into kernel
2178  *      space and check the user space data area is readable before invoking
2179  *      the protocol.
2180  */
2181 int __sys_sendto(int fd, void __user *buff, size_t len, unsigned int flags,
2182                  struct sockaddr __user *addr,  int addr_len)
2183 {
2184         struct socket *sock;
2185         struct sockaddr_storage address;
2186         int err;
2187         struct msghdr msg;
2188         int fput_needed;
2189 
2190         err = import_ubuf(ITER_SOURCE, buff, len, &msg.msg_iter);
2191         if (unlikely(err))
2192                 return err;
2193         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2194         if (!sock)
2195                 goto out;
2196 
2197         msg.msg_name = NULL;
2198         msg.msg_control = NULL;
2199         msg.msg_controllen = 0;
2200         msg.msg_namelen = 0;
2201         msg.msg_ubuf = NULL;
2202         if (addr) {
2203                 err = move_addr_to_kernel(addr, addr_len, &address);
2204                 if (err < 0)
2205                         goto out_put;
2206                 msg.msg_name = (struct sockaddr *)&address;
2207                 msg.msg_namelen = addr_len;
2208         }
2209         flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
2210         if (sock->file->f_flags & O_NONBLOCK)
2211                 flags |= MSG_DONTWAIT;
2212         msg.msg_flags = flags;
2213         err = __sock_sendmsg(sock, &msg);
2214 
2215 out_put:
2216         fput_light(sock->file, fput_needed);
2217 out:
2218         return err;
2219 }
2220 
2221 SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
2222                 unsigned int, flags, struct sockaddr __user *, addr,
2223                 int, addr_len)
2224 {
2225         return __sys_sendto(fd, buff, len, flags, addr, addr_len);
2226 }
2227 
2228 /*
2229  *      Send a datagram down a socket.
2230  */
2231 
2232 SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
2233                 unsigned int, flags)
2234 {
2235         return __sys_sendto(fd, buff, len, flags, NULL, 0);
2236 }
2237 
2238 /*
2239  *      Receive a frame from the socket and optionally record the address of the
2240  *      sender. We verify the buffers are writable and if needed move the
2241  *      sender address from kernel to user space.
2242  */
2243 int __sys_recvfrom(int fd, void __user *ubuf, size_t size, unsigned int flags,
2244                    struct sockaddr __user *addr, int __user *addr_len)
2245 {
2246         struct sockaddr_storage address;
2247         struct msghdr msg = {
2248                 /* Save some cycles and don't copy the address if not needed */
2249                 .msg_name = addr ? (struct sockaddr *)&address : NULL,
2250         };
2251         struct socket *sock;
2252         int err, err2;
2253         int fput_needed;
2254 
2255         err = import_ubuf(ITER_DEST, ubuf, size, &msg.msg_iter);
2256         if (unlikely(err))
2257                 return err;
2258         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2259         if (!sock)
2260                 goto out;
2261 
2262         if (sock->file->f_flags & O_NONBLOCK)
2263                 flags |= MSG_DONTWAIT;
2264         err = sock_recvmsg(sock, &msg, flags);
2265 
2266         if (err >= 0 && addr != NULL) {
2267                 err2 = move_addr_to_user(&address,
2268                                          msg.msg_namelen, addr, addr_len);
2269                 if (err2 < 0)
2270                         err = err2;
2271         }
2272 
2273         fput_light(sock->file, fput_needed);
2274 out:
2275         return err;
2276 }
2277 
2278 SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
2279                 unsigned int, flags, struct sockaddr __user *, addr,
2280                 int __user *, addr_len)
2281 {
2282         return __sys_recvfrom(fd, ubuf, size, flags, addr, addr_len);
2283 }
2284 
2285 /*
2286  *      Receive a datagram from a socket.
2287  */
2288 
2289 SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
2290                 unsigned int, flags)
2291 {
2292         return __sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
2293 }
2294 
2295 static bool sock_use_custom_sol_socket(const struct socket *sock)
2296 {
2297         return test_bit(SOCK_CUSTOM_SOCKOPT, &sock->flags);
2298 }
2299 
2300 int do_sock_setsockopt(struct socket *sock, bool compat, int level,
2301                        int optname, sockptr_t optval, int optlen)
2302 {
2303         const struct proto_ops *ops;
2304         char *kernel_optval = NULL;
2305         int err;
2306 
2307         if (optlen < 0)
2308                 return -EINVAL;
2309 
2310         err = security_socket_setsockopt(sock, level, optname);
2311         if (err)
2312                 goto out_put;
2313 
2314         if (!compat)
2315                 err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level, &optname,
2316                                                      optval, &optlen,
2317                                                      &kernel_optval);
2318         if (err < 0)
2319                 goto out_put;
2320         if (err > 0) {
2321                 err = 0;
2322                 goto out_put;
2323         }
2324 
2325         if (kernel_optval)
2326                 optval = KERNEL_SOCKPTR(kernel_optval);
2327         ops = READ_ONCE(sock->ops);
2328         if (level == SOL_SOCKET && !sock_use_custom_sol_socket(sock))
2329                 err = sock_setsockopt(sock, level, optname, optval, optlen);
2330         else if (unlikely(!ops->setsockopt))
2331                 err = -EOPNOTSUPP;
2332         else
2333                 err = ops->setsockopt(sock, level, optname, optval,
2334                                             optlen);
2335         kfree(kernel_optval);
2336 out_put:
2337         return err;
2338 }
2339 EXPORT_SYMBOL(do_sock_setsockopt);
2340 
2341 /* Set a socket option. Because we don't know the option lengths we have
2342  * to pass the user mode parameter for the protocols to sort out.
2343  */
2344 int __sys_setsockopt(int fd, int level, int optname, char __user *user_optval,
2345                      int optlen)
2346 {
2347         sockptr_t optval = USER_SOCKPTR(user_optval);
2348         bool compat = in_compat_syscall();
2349         int err, fput_needed;
2350         struct socket *sock;
2351 
2352         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2353         if (!sock)
2354                 return err;
2355 
2356         err = do_sock_setsockopt(sock, compat, level, optname, optval, optlen);
2357 
2358         fput_light(sock->file, fput_needed);
2359         return err;
2360 }
2361 
2362 SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
2363                 char __user *, optval, int, optlen)
2364 {
2365         return __sys_setsockopt(fd, level, optname, optval, optlen);
2366 }
2367 
2368 INDIRECT_CALLABLE_DECLARE(bool tcp_bpf_bypass_getsockopt(int level,
2369                                                          int optname));
2370 
2371 int do_sock_getsockopt(struct socket *sock, bool compat, int level,
2372                        int optname, sockptr_t optval, sockptr_t optlen)
2373 {
2374         int max_optlen __maybe_unused = 0;
2375         const struct proto_ops *ops;
2376         int err;
2377 
2378         err = security_socket_getsockopt(sock, level, optname);
2379         if (err)
2380                 return err;
2381 
2382         if (!compat)
2383                 copy_from_sockptr(&max_optlen, optlen, sizeof(int));
2384 
2385         ops = READ_ONCE(sock->ops);
2386         if (level == SOL_SOCKET) {
2387                 err = sk_getsockopt(sock->sk, level, optname, optval, optlen);
2388         } else if (unlikely(!ops->getsockopt)) {
2389                 err = -EOPNOTSUPP;
2390         } else {
2391                 if (WARN_ONCE(optval.is_kernel || optlen.is_kernel,
2392                               "Invalid argument type"))
2393                         return -EOPNOTSUPP;
2394 
2395                 err = ops->getsockopt(sock, level, optname, optval.user,
2396                                       optlen.user);
2397         }
2398 
2399         if (!compat)
2400                 err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
2401                                                      optval, optlen, max_optlen,
2402                                                      err);
2403 
2404         return err;
2405 }
2406 EXPORT_SYMBOL(do_sock_getsockopt);
2407 
2408 /*
2409  *      Get a socket option. Because we don't know the option lengths we have
2410  *      to pass a user mode parameter for the protocols to sort out.
2411  */
2412 int __sys_getsockopt(int fd, int level, int optname, char __user *optval,
2413                 int __user *optlen)
2414 {
2415         int err, fput_needed;
2416         struct socket *sock;
2417         bool compat;
2418 
2419         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2420         if (!sock)
2421                 return err;
2422 
2423         compat = in_compat_syscall();
2424         err = do_sock_getsockopt(sock, compat, level, optname,
2425                                  USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
2426 
2427         fput_light(sock->file, fput_needed);
2428         return err;
2429 }
2430 
2431 SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
2432                 char __user *, optval, int __user *, optlen)
2433 {
2434         return __sys_getsockopt(fd, level, optname, optval, optlen);
2435 }
2436 
2437 /*
2438  *      Shutdown a socket.
2439  */
2440 
2441 int __sys_shutdown_sock(struct socket *sock, int how)
2442 {
2443         int err;
2444 
2445         err = security_socket_shutdown(sock, how);
2446         if (!err)
2447                 err = READ_ONCE(sock->ops)->shutdown(sock, how);
2448 
2449         return err;
2450 }
2451 
2452 int __sys_shutdown(int fd, int how)
2453 {
2454         int err, fput_needed;
2455         struct socket *sock;
2456 
2457         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2458         if (sock != NULL) {
2459                 err = __sys_shutdown_sock(sock, how);
2460                 fput_light(sock->file, fput_needed);
2461         }
2462         return err;
2463 }
2464 
2465 SYSCALL_DEFINE2(shutdown, int, fd, int, how)
2466 {
2467         return __sys_shutdown(fd, how);
2468 }
2469 
2470 /* A couple of helpful macros for getting the address of the 32/64 bit
2471  * fields which are the same type (int / unsigned) on our platforms.
2472  */
2473 #define COMPAT_MSG(msg, member) ((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
2474 #define COMPAT_NAMELEN(msg)     COMPAT_MSG(msg, msg_namelen)
2475 #define COMPAT_FLAGS(msg)       COMPAT_MSG(msg, msg_flags)
2476 
2477 struct used_address {
2478         struct sockaddr_storage name;
2479         unsigned int name_len;
2480 };
2481 
2482 int __copy_msghdr(struct msghdr *kmsg,
2483                   struct user_msghdr *msg,
2484                   struct sockaddr __user **save_addr)
2485 {
2486         ssize_t err;
2487 
2488         kmsg->msg_control_is_user = true;
2489         kmsg->msg_get_inq = 0;
2490         kmsg->msg_control_user = msg->msg_control;
2491         kmsg->msg_controllen = msg->msg_controllen;
2492         kmsg->msg_flags = msg->msg_flags;
2493 
2494         kmsg->msg_namelen = msg->msg_namelen;
2495         if (!msg->msg_name)
2496                 kmsg->msg_namelen = 0;
2497 
2498         if (kmsg->msg_namelen < 0)
2499                 return -EINVAL;
2500 
2501         if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
2502                 kmsg->msg_namelen = sizeof(struct sockaddr_storage);
2503 
2504         if (save_addr)
2505                 *save_addr = msg->msg_name;
2506 
2507         if (msg->msg_name && kmsg->msg_namelen) {
2508                 if (!save_addr) {
2509                         err = move_addr_to_kernel(msg->msg_name,
2510                                                   kmsg->msg_namelen,
2511                                                   kmsg->msg_name);
2512                         if (err < 0)
2513                                 return err;
2514                 }
2515         } else {
2516                 kmsg->msg_name = NULL;
2517                 kmsg->msg_namelen = 0;
2518         }
2519 
2520         if (msg->msg_iovlen > UIO_MAXIOV)
2521                 return -EMSGSIZE;
2522 
2523         kmsg->msg_iocb = NULL;
2524         kmsg->msg_ubuf = NULL;
2525         return 0;
2526 }
2527 
2528 static int copy_msghdr_from_user(struct msghdr *kmsg,
2529                                  struct user_msghdr __user *umsg,
2530                                  struct sockaddr __user **save_addr,
2531                                  struct iovec **iov)
2532 {
2533         struct user_msghdr msg;
2534         ssize_t err;
2535 
2536         if (copy_from_user(&msg, umsg, sizeof(*umsg)))
2537                 return -EFAULT;
2538 
2539         err = __copy_msghdr(kmsg, &msg, save_addr);
2540         if (err)
2541                 return err;
2542 
2543         err = import_iovec(save_addr ? ITER_DEST : ITER_SOURCE,
2544                             msg.msg_iov, msg.msg_iovlen,
2545                             UIO_FASTIOV, iov, &kmsg->msg_iter);
2546         return err < 0 ? err : 0;
2547 }
2548 
2549 static int ____sys_sendmsg(struct socket *sock, struct msghdr *msg_sys,
2550                            unsigned int flags, struct used_address *used_address,
2551                            unsigned int allowed_msghdr_flags)
2552 {
2553         unsigned char ctl[sizeof(struct cmsghdr) + 20]
2554                                 __aligned(sizeof(__kernel_size_t));
2555         /* 20 is size of ipv6_pktinfo */
2556         unsigned char *ctl_buf = ctl;
2557         int ctl_len;
2558         ssize_t err;
2559 
2560         err = -ENOBUFS;
2561 
2562         if (msg_sys->msg_controllen > INT_MAX)
2563                 goto out;
2564         flags |= (msg_sys->msg_flags & allowed_msghdr_flags);
2565         ctl_len = msg_sys->msg_controllen;
2566         if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
2567                 err =
2568                     cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl,
2569                                                      sizeof(ctl));
2570                 if (err)
2571                         goto out;
2572                 ctl_buf = msg_sys->msg_control;
2573                 ctl_len = msg_sys->msg_controllen;
2574         } else if (ctl_len) {
2575                 BUILD_BUG_ON(sizeof(struct cmsghdr) !=
2576                              CMSG_ALIGN(sizeof(struct cmsghdr)));
2577                 if (ctl_len > sizeof(ctl)) {
2578                         ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
2579                         if (ctl_buf == NULL)
2580                                 goto out;
2581                 }
2582                 err = -EFAULT;
2583                 if (copy_from_user(ctl_buf, msg_sys->msg_control_user, ctl_len))
2584                         goto out_freectl;
2585                 msg_sys->msg_control = ctl_buf;
2586                 msg_sys->msg_control_is_user = false;
2587         }
2588         flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
2589         msg_sys->msg_flags = flags;
2590 
2591         if (sock->file->f_flags & O_NONBLOCK)
2592                 msg_sys->msg_flags |= MSG_DONTWAIT;
2593         /*
2594          * If this is sendmmsg() and current destination address is same as
2595          * previously succeeded address, omit asking LSM's decision.
2596          * used_address->name_len is initialized to UINT_MAX so that the first
2597          * destination address never matches.
2598          */
2599         if (used_address && msg_sys->msg_name &&
2600             used_address->name_len == msg_sys->msg_namelen &&
2601             !memcmp(&used_address->name, msg_sys->msg_name,
2602                     used_address->name_len)) {
2603                 err = sock_sendmsg_nosec(sock, msg_sys);
2604                 goto out_freectl;
2605         }
2606         err = __sock_sendmsg(sock, msg_sys);
2607         /*
2608          * If this is sendmmsg() and sending to current destination address was
2609          * successful, remember it.
2610          */
2611         if (used_address && err >= 0) {
2612                 used_address->name_len = msg_sys->msg_namelen;
2613                 if (msg_sys->msg_name)
2614                         memcpy(&used_address->name, msg_sys->msg_name,
2615                                used_address->name_len);
2616         }
2617 
2618 out_freectl:
2619         if (ctl_buf != ctl)
2620                 sock_kfree_s(sock->sk, ctl_buf, ctl_len);
2621 out:
2622         return err;
2623 }
2624 
2625 static int sendmsg_copy_msghdr(struct msghdr *msg,
2626                                struct user_msghdr __user *umsg, unsigned flags,
2627                                struct iovec **iov)
2628 {
2629         int err;
2630 
2631         if (flags & MSG_CMSG_COMPAT) {
2632                 struct compat_msghdr __user *msg_compat;
2633 
2634                 msg_compat = (struct compat_msghdr __user *) umsg;
2635                 err = get_compat_msghdr(msg, msg_compat, NULL, iov);
2636         } else {
2637                 err = copy_msghdr_from_user(msg, umsg, NULL, iov);
2638         }
2639         if (err < 0)
2640                 return err;
2641 
2642         return 0;
2643 }
2644 
2645 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
2646                          struct msghdr *msg_sys, unsigned int flags,
2647                          struct used_address *used_address,
2648                          unsigned int allowed_msghdr_flags)
2649 {
2650         struct sockaddr_storage address;
2651         struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
2652         ssize_t err;
2653 
2654         msg_sys->msg_name = &address;
2655 
2656         err = sendmsg_copy_msghdr(msg_sys, msg, flags, &iov);
2657         if (err < 0)
2658                 return err;
2659 
2660         err = ____sys_sendmsg(sock, msg_sys, flags, used_address,
2661                                 allowed_msghdr_flags);
2662         kfree(iov);
2663         return err;
2664 }
2665 
2666 /*
2667  *      BSD sendmsg interface
2668  */
2669 long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,
2670                         unsigned int flags)
2671 {
2672         return ____sys_sendmsg(sock, msg, flags, NULL, 0);
2673 }
2674 
2675 long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2676                    bool forbid_cmsg_compat)
2677 {
2678         int fput_needed, err;
2679         struct msghdr msg_sys;
2680         struct socket *sock;
2681 
2682         if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2683                 return -EINVAL;
2684 
2685         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2686         if (!sock)
2687                 goto out;
2688 
2689         err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL, 0);
2690 
2691         fput_light(sock->file, fput_needed);
2692 out:
2693         return err;
2694 }
2695 
2696 SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
2697 {
2698         return __sys_sendmsg(fd, msg, flags, true);
2699 }
2700 
2701 /*
2702  *      Linux sendmmsg interface
2703  */
2704 
2705 int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2706                    unsigned int flags, bool forbid_cmsg_compat)
2707 {
2708         int fput_needed, err, datagrams;
2709         struct socket *sock;
2710         struct mmsghdr __user *entry;
2711         struct compat_mmsghdr __user *compat_entry;
2712         struct msghdr msg_sys;
2713         struct used_address used_address;
2714         unsigned int oflags = flags;
2715 
2716         if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2717                 return -EINVAL;
2718 
2719         if (vlen > UIO_MAXIOV)
2720                 vlen = UIO_MAXIOV;
2721 
2722         datagrams = 0;
2723 
2724         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2725         if (!sock)
2726                 return err;
2727 
2728         used_address.name_len = UINT_MAX;
2729         entry = mmsg;
2730         compat_entry = (struct compat_mmsghdr __user *)mmsg;
2731         err = 0;
2732         flags |= MSG_BATCH;
2733 
2734         while (datagrams < vlen) {
2735                 if (datagrams == vlen - 1)
2736                         flags = oflags;
2737 
2738                 if (MSG_CMSG_COMPAT & flags) {
2739                         err = ___sys_sendmsg(sock, (struct user_msghdr __user *)compat_entry,
2740                                              &msg_sys, flags, &used_address, MSG_EOR);
2741                         if (err < 0)
2742                                 break;
2743                         err = __put_user(err, &compat_entry->msg_len);
2744                         ++compat_entry;
2745                 } else {
2746                         err = ___sys_sendmsg(sock,
2747                                              (struct user_msghdr __user *)entry,
2748                                              &msg_sys, flags, &used_address, MSG_EOR);
2749                         if (err < 0)
2750                                 break;
2751                         err = put_user(err, &entry->msg_len);
2752                         ++entry;
2753                 }
2754 
2755                 if (err)
2756                         break;
2757                 ++datagrams;
2758                 if (msg_data_left(&msg_sys))
2759                         break;
2760                 cond_resched();
2761         }
2762 
2763         fput_light(sock->file, fput_needed);
2764 
2765         /* We only return an error if no datagrams were able to be sent */
2766         if (datagrams != 0)
2767                 return datagrams;
2768 
2769         return err;
2770 }
2771 
2772 SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
2773                 unsigned int, vlen, unsigned int, flags)
2774 {
2775         return __sys_sendmmsg(fd, mmsg, vlen, flags, true);
2776 }
2777 
2778 static int recvmsg_copy_msghdr(struct msghdr *msg,
2779                                struct user_msghdr __user *umsg, unsigned flags,
2780                                struct sockaddr __user **uaddr,
2781                                struct iovec **iov)
2782 {
2783         ssize_t err;
2784 
2785         if (MSG_CMSG_COMPAT & flags) {
2786                 struct compat_msghdr __user *msg_compat;
2787 
2788                 msg_compat = (struct compat_msghdr __user *) umsg;
2789                 err = get_compat_msghdr(msg, msg_compat, uaddr, iov);
2790         } else {
2791                 err = copy_msghdr_from_user(msg, umsg, uaddr, iov);
2792         }
2793         if (err < 0)
2794                 return err;
2795 
2796         return 0;
2797 }
2798 
2799 static int ____sys_recvmsg(struct socket *sock, struct msghdr *msg_sys,
2800                            struct user_msghdr __user *msg,
2801                            struct sockaddr __user *uaddr,
2802                            unsigned int flags, int nosec)
2803 {
2804         struct compat_msghdr __user *msg_compat =
2805                                         (struct compat_msghdr __user *) msg;
2806         int __user *uaddr_len = COMPAT_NAMELEN(msg);
2807         struct sockaddr_storage addr;
2808         unsigned long cmsg_ptr;
2809         int len;
2810         ssize_t err;
2811 
2812         msg_sys->msg_name = &addr;
2813         cmsg_ptr = (unsigned long)msg_sys->msg_control;
2814         msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
2815 
2816         /* We assume all kernel code knows the size of sockaddr_storage */
2817         msg_sys->msg_namelen = 0;
2818 
2819         if (sock->file->f_flags & O_NONBLOCK)
2820                 flags |= MSG_DONTWAIT;
2821 
2822         if (unlikely(nosec))
2823                 err = sock_recvmsg_nosec(sock, msg_sys, flags);
2824         else
2825                 err = sock_recvmsg(sock, msg_sys, flags);
2826 
2827         if (err < 0)
2828                 goto out;
2829         len = err;
2830 
2831         if (uaddr != NULL) {
2832                 err = move_addr_to_user(&addr,
2833                                         msg_sys->msg_namelen, uaddr,
2834                                         uaddr_len);
2835                 if (err < 0)
2836                         goto out;
2837         }
2838         err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
2839                          COMPAT_FLAGS(msg));
2840         if (err)
2841                 goto out;
2842         if (MSG_CMSG_COMPAT & flags)
2843                 err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2844                                  &msg_compat->msg_controllen);
2845         else
2846                 err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2847                                  &msg->msg_controllen);
2848         if (err)
2849                 goto out;
2850         err = len;
2851 out:
2852         return err;
2853 }
2854 
2855 static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
2856                          struct msghdr *msg_sys, unsigned int flags, int nosec)
2857 {
2858         struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
2859         /* user mode address pointers */
2860         struct sockaddr __user *uaddr;
2861         ssize_t err;
2862 
2863         err = recvmsg_copy_msghdr(msg_sys, msg, flags, &uaddr, &iov);
2864         if (err < 0)
2865                 return err;
2866 
2867         err = ____sys_recvmsg(sock, msg_sys, msg, uaddr, flags, nosec);
2868         kfree(iov);
2869         return err;
2870 }
2871 
2872 /*
2873  *      BSD recvmsg interface
2874  */
2875 
2876 long __sys_recvmsg_sock(struct socket *sock, struct msghdr *msg,
2877                         struct user_msghdr __user *umsg,
2878                         struct sockaddr __user *uaddr, unsigned int flags)
2879 {
2880         return ____sys_recvmsg(sock, msg, umsg, uaddr, flags, 0);
2881 }
2882 
2883 long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
2884                    bool forbid_cmsg_compat)
2885 {
2886         int fput_needed, err;
2887         struct msghdr msg_sys;
2888         struct socket *sock;
2889 
2890         if (forbid_cmsg_compat && (flags & MSG_CMSG_COMPAT))
2891                 return -EINVAL;
2892 
2893         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2894         if (!sock)
2895                 goto out;
2896 
2897         err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
2898 
2899         fput_light(sock->file, fput_needed);
2900 out:
2901         return err;
2902 }
2903 
2904 SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
2905                 unsigned int, flags)
2906 {
2907         return __sys_recvmsg(fd, msg, flags, true);
2908 }
2909 
2910 /*
2911  *     Linux recvmmsg interface
2912  */
2913 
2914 static int do_recvmmsg(int fd, struct mmsghdr __user *mmsg,
2915                           unsigned int vlen, unsigned int flags,
2916                           struct timespec64 *timeout)
2917 {
2918         int fput_needed, err, datagrams;
2919         struct socket *sock;
2920         struct mmsghdr __user *entry;
2921         struct compat_mmsghdr __user *compat_entry;
2922         struct msghdr msg_sys;
2923         struct timespec64 end_time;
2924         struct timespec64 timeout64;
2925 
2926         if (timeout &&
2927             poll_select_set_timeout(&end_time, timeout->tv_sec,
2928                                     timeout->tv_nsec))
2929                 return -EINVAL;
2930 
2931         datagrams = 0;
2932 
2933         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2934         if (!sock)
2935                 return err;
2936 
2937         if (likely(!(flags & MSG_ERRQUEUE))) {
2938                 err = sock_error(sock->sk);
2939                 if (err) {
2940                         datagrams = err;
2941                         goto out_put;
2942                 }
2943         }
2944 
2945         entry = mmsg;
2946         compat_entry = (struct compat_mmsghdr __user *)mmsg;
2947 
2948         while (datagrams < vlen) {
2949                 /*
2950                  * No need to ask LSM for more than the first datagram.
2951                  */
2952                 if (MSG_CMSG_COMPAT & flags) {
2953                         err = ___sys_recvmsg(sock, (struct user_msghdr __user *)compat_entry,
2954                                              &msg_sys, flags & ~MSG_WAITFORONE,
2955                                              datagrams);
2956                         if (err < 0)
2957                                 break;
2958                         err = __put_user(err, &compat_entry->msg_len);
2959                         ++compat_entry;
2960                 } else {
2961                         err = ___sys_recvmsg(sock,
2962                                              (struct user_msghdr __user *)entry,
2963                                              &msg_sys, flags & ~MSG_WAITFORONE,
2964                                              datagrams);
2965                         if (err < 0)
2966                                 break;
2967                         err = put_user(err, &entry->msg_len);
2968                         ++entry;
2969                 }
2970 
2971                 if (err)
2972                         break;
2973                 ++datagrams;
2974 
2975                 /* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */
2976                 if (flags & MSG_WAITFORONE)
2977                         flags |= MSG_DONTWAIT;
2978 
2979                 if (timeout) {
2980                         ktime_get_ts64(&timeout64);
2981                         *timeout = timespec64_sub(end_time, timeout64);
2982                         if (timeout->tv_sec < 0) {
2983                                 timeout->tv_sec = timeout->tv_nsec = 0;
2984                                 break;
2985                         }
2986 
2987                         /* Timeout, return less than vlen datagrams */
2988                         if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
2989                                 break;
2990                 }
2991 
2992                 /* Out of band data, return right away */
2993                 if (msg_sys.msg_flags & MSG_OOB)
2994                         break;
2995                 cond_resched();
2996         }
2997 
2998         if (err == 0)
2999                 goto out_put;
3000 
3001         if (datagrams == 0) {
3002                 datagrams = err;
3003                 goto out_put;
3004         }
3005 
3006         /*
3007          * We may return less entries than requested (vlen) if the
3008          * sock is non block and there aren't enough datagrams...
3009          */
3010         if (err != -EAGAIN) {
3011                 /*
3012                  * ... or  if recvmsg returns an error after we
3013                  * received some datagrams, where we record the
3014                  * error to return on the next call or if the
3015                  * app asks about it using getsockopt(SO_ERROR).
3016                  */
3017                 WRITE_ONCE(sock->sk->sk_err, -err);
3018         }
3019 out_put:
3020         fput_light(sock->file, fput_needed);
3021 
3022         return datagrams;
3023 }
3024 
3025 int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
3026                    unsigned int vlen, unsigned int flags,
3027                    struct __kernel_timespec __user *timeout,
3028                    struct old_timespec32 __user *timeout32)
3029 {
3030         int datagrams;
3031         struct timespec64 timeout_sys;
3032 
3033         if (timeout && get_timespec64(&timeout_sys, timeout))
3034                 return -EFAULT;
3035 
3036         if (timeout32 && get_old_timespec32(&timeout_sys, timeout32))
3037                 return -EFAULT;
3038 
3039         if (!timeout && !timeout32)
3040                 return do_recvmmsg(fd, mmsg, vlen, flags, NULL);
3041 
3042         datagrams = do_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
3043 
3044         if (datagrams <= 0)
3045                 return datagrams;
3046 
3047         if (timeout && put_timespec64(&timeout_sys, timeout))
3048                 datagrams = -EFAULT;
3049 
3050         if (timeout32 && put_old_timespec32(&timeout_sys, timeout32))
3051                 datagrams = -EFAULT;
3052 
3053         return datagrams;
3054 }
3055 
3056 SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
3057                 unsigned int, vlen, unsigned int, flags,
3058                 struct __kernel_timespec __user *, timeout)
3059 {
3060         if (flags & MSG_CMSG_COMPAT)
3061                 return -EINVAL;
3062 
3063         return __sys_recvmmsg(fd, mmsg, vlen, flags, timeout, NULL);
3064 }
3065 
3066 #ifdef CONFIG_COMPAT_32BIT_TIME
3067 SYSCALL_DEFINE5(recvmmsg_time32, int, fd, struct mmsghdr __user *, mmsg,
3068                 unsigned int, vlen, unsigned int, flags,
3069                 struct old_timespec32 __user *, timeout)
3070 {
3071         if (flags & MSG_CMSG_COMPAT)
3072                 return -EINVAL;
3073 
3074         return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL, timeout);
3075 }
3076 #endif
3077 
3078 #ifdef __ARCH_WANT_SYS_SOCKETCALL
3079 /* Argument list sizes for sys_socketcall */
3080 #define AL(x) ((x) * sizeof(unsigned long))
3081 static const unsigned char nargs[21] = {
3082         AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
3083         AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
3084         AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
3085         AL(4), AL(5), AL(4)
3086 };
3087 
3088 #undef AL
3089 
3090 /*
3091  *      System call vectors.
3092  *
3093  *      Argument checking cleaned up. Saved 20% in size.
3094  *  This function doesn't need to set the kernel lock because
3095  *  it is set by the callees.
3096  */
3097 
3098 SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
3099 {
3100         unsigned long a[AUDITSC_ARGS];
3101         unsigned long a0, a1;
3102         int err;
3103         unsigned int len;
3104 
3105         if (call < 1 || call > SYS_SENDMMSG)
3106                 return -EINVAL;
3107         call = array_index_nospec(call, SYS_SENDMMSG + 1);
3108 
3109         len = nargs[call];
3110         if (len > sizeof(a))
3111                 return -EINVAL;
3112 
3113         /* copy_from_user should be SMP safe. */
3114         if (copy_from_user(a, args, len))
3115                 return -EFAULT;
3116 
3117         err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
3118         if (err)
3119                 return err;
3120 
3121         a0 = a[0];
3122         a1 = a[1];
3123 
3124         switch (call) {
3125         case SYS_SOCKET:
3126                 err = __sys_socket(a0, a1, a[2]);
3127                 break;
3128         case SYS_BIND:
3129                 err = __sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
3130                 break;
3131         case SYS_CONNECT:
3132                 err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
3133                 break;
3134         case SYS_LISTEN:
3135                 err = __sys_listen(a0, a1);
3136                 break;
3137         case SYS_ACCEPT:
3138                 err = __sys_accept4(a0, (struct sockaddr __user *)a1,
3139                                     (int __user *)a[2], 0);
3140                 break;
3141         case SYS_GETSOCKNAME:
3142                 err =
3143                     __sys_getsockname(a0, (struct sockaddr __user *)a1,
3144                                       (int __user *)a[2]);
3145                 break;
3146         case SYS_GETPEERNAME:
3147                 err =
3148                     __sys_getpeername(a0, (struct sockaddr __user *)a1,
3149                                       (int __user *)a[2]);
3150                 break;
3151         case SYS_SOCKETPAIR:
3152                 err = __sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
3153                 break;
3154         case SYS_SEND:
3155                 err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
3156                                    NULL, 0);
3157                 break;
3158         case SYS_SENDTO:
3159                 err = __sys_sendto(a0, (void __user *)a1, a[2], a[3],
3160                                    (struct sockaddr __user *)a[4], a[5]);
3161                 break;
3162         case SYS_RECV:
3163                 err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
3164                                      NULL, NULL);
3165                 break;
3166         case SYS_RECVFROM:
3167                 err = __sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
3168                                      (struct sockaddr __user *)a[4],
3169                                      (int __user *)a[5]);
3170                 break;
3171         case SYS_SHUTDOWN:
3172                 err = __sys_shutdown(a0, a1);
3173                 break;
3174         case SYS_SETSOCKOPT:
3175                 err = __sys_setsockopt(a0, a1, a[2], (char __user *)a[3],
3176                                        a[4]);
3177                 break;
3178         case SYS_GETSOCKOPT:
3179                 err =
3180                     __sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
3181                                      (int __user *)a[4]);
3182                 break;
3183         case SYS_SENDMSG:
3184                 err = __sys_sendmsg(a0, (struct user_msghdr __user *)a1,
3185                                     a[2], true);
3186                 break;
3187         case SYS_SENDMMSG:
3188                 err = __sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2],
3189                                      a[3], true);
3190                 break;
3191         case SYS_RECVMSG:
3192                 err = __sys_recvmsg(a0, (struct user_msghdr __user *)a1,
3193                                     a[2], true);
3194                 break;
3195         case SYS_RECVMMSG:
3196                 if (IS_ENABLED(CONFIG_64BIT))
3197                         err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
3198                                              a[2], a[3],
3199                                              (struct __kernel_timespec __user *)a[4],
3200                                              NULL);
3201                 else
3202                         err = __sys_recvmmsg(a0, (struct mmsghdr __user *)a1,
3203                                              a[2], a[3], NULL,
3204                                              (struct old_timespec32 __user *)a[4]);
3205                 break;
3206         case SYS_ACCEPT4:
3207                 err = __sys_accept4(a0, (struct sockaddr __user *)a1,
3208                                     (int __user *)a[2], a[3]);
3209                 break;
3210         default:
3211                 err = -EINVAL;
3212                 break;
3213         }
3214         return err;
3215 }
3216 
3217 #endif                          /* __ARCH_WANT_SYS_SOCKETCALL */
3218 
3219 /**
3220  *      sock_register - add a socket protocol handler
3221  *      @ops: description of protocol
3222  *
3223  *      This function is called by a protocol handler that wants to
3224  *      advertise its address family, and have it linked into the
3225  *      socket interface. The value ops->family corresponds to the
3226  *      socket system call protocol family.
3227  */
3228 int sock_register(const struct net_proto_family *ops)
3229 {
3230         int err;
3231 
3232         if (ops->family >= NPROTO) {
3233                 pr_crit("protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
3234                 return -ENOBUFS;
3235         }
3236 
3237         spin_lock(&net_family_lock);
3238         if (rcu_dereference_protected(net_families[ops->family],
3239                                       lockdep_is_held(&net_family_lock)))
3240                 err = -EEXIST;
3241         else {
3242                 rcu_assign_pointer(net_families[ops->family], ops);
3243                 err = 0;
3244         }
3245         spin_unlock(&net_family_lock);
3246 
3247         pr_info("NET: Registered %s protocol family\n", pf_family_names[ops->family]);
3248         return err;
3249 }
3250 EXPORT_SYMBOL(sock_register);
3251 
3252 /**
3253  *      sock_unregister - remove a protocol handler
3254  *      @family: protocol family to remove
3255  *
3256  *      This function is called by a protocol handler that wants to
3257  *      remove its address family, and have it unlinked from the
3258  *      new socket creation.
3259  *
3260  *      If protocol handler is a module, then it can use module reference
3261  *      counts to protect against new references. If protocol handler is not
3262  *      a module then it needs to provide its own protection in
3263  *      the ops->create routine.
3264  */
3265 void sock_unregister(int family)
3266 {
3267         BUG_ON(family < 0 || family >= NPROTO);
3268 
3269         spin_lock(&net_family_lock);
3270         RCU_INIT_POINTER(net_families[family], NULL);
3271         spin_unlock(&net_family_lock);
3272 
3273         synchronize_rcu();
3274 
3275         pr_info("NET: Unregistered %s protocol family\n", pf_family_names[family]);
3276 }
3277 EXPORT_SYMBOL(sock_unregister);
3278 
3279 bool sock_is_registered(int family)
3280 {
3281         return family < NPROTO && rcu_access_pointer(net_families[family]);
3282 }
3283 
3284 static int __init sock_init(void)
3285 {
3286         int err;
3287         /*
3288          *      Initialize the network sysctl infrastructure.
3289          */
3290         err = net_sysctl_init();
3291         if (err)
3292                 goto out;
3293 
3294         /*
3295          *      Initialize skbuff SLAB cache
3296          */
3297         skb_init();
3298 
3299         /*
3300          *      Initialize the protocols module.
3301          */
3302 
3303         init_inodecache();
3304 
3305         err = register_filesystem(&sock_fs_type);
3306         if (err)
3307                 goto out;
3308         sock_mnt = kern_mount(&sock_fs_type);
3309         if (IS_ERR(sock_mnt)) {
3310                 err = PTR_ERR(sock_mnt);
3311                 goto out_mount;
3312         }
3313 
3314         /* The real protocol initialization is performed in later initcalls.
3315          */
3316 
3317 #ifdef CONFIG_NETFILTER
3318         err = netfilter_init();
3319         if (err)
3320                 goto out;
3321 #endif
3322 
3323         ptp_classifier_init();
3324 
3325 out:
3326         return err;
3327 
3328 out_mount:
3329         unregister_filesystem(&sock_fs_type);
3330         goto out;
3331 }
3332 
3333 core_initcall(sock_init);       /* early initcall */
3334 
3335 #ifdef CONFIG_PROC_FS
3336 void socket_seq_show(struct seq_file *seq)
3337 {
3338         seq_printf(seq, "sockets: used %d\n",
3339                    sock_inuse_get(seq->private));
3340 }
3341 #endif                          /* CONFIG_PROC_FS */
3342 
3343 /* Handle the fact that while struct ifreq has the same *layout* on
3344  * 32/64 for everything but ifreq::ifru_ifmap and ifreq::ifru_data,
3345  * which are handled elsewhere, it still has different *size* due to
3346  * ifreq::ifru_ifmap (which is 16 bytes on 32 bit, 24 bytes on 64-bit,
3347  * resulting in struct ifreq being 32 and 40 bytes respectively).
3348  * As a result, if the struct happens to be at the end of a page and
3349  * the next page isn't readable/writable, we get a fault. To prevent
3350  * that, copy back and forth to the full size.
3351  */
3352 int get_user_ifreq(struct ifreq *ifr, void __user **ifrdata, void __user *arg)
3353 {
3354         if (in_compat_syscall()) {
3355                 struct compat_ifreq *ifr32 = (struct compat_ifreq *)ifr;
3356 
3357                 memset(ifr, 0, sizeof(*ifr));
3358                 if (copy_from_user(ifr32, arg, sizeof(*ifr32)))
3359                         return -EFAULT;
3360 
3361                 if (ifrdata)
3362                         *ifrdata = compat_ptr(ifr32->ifr_data);
3363 
3364                 return 0;
3365         }
3366 
3367         if (copy_from_user(ifr, arg, sizeof(*ifr)))
3368                 return -EFAULT;
3369 
3370         if (ifrdata)
3371                 *ifrdata = ifr->ifr_data;
3372 
3373         return 0;
3374 }
3375 EXPORT_SYMBOL(get_user_ifreq);
3376 
3377 int put_user_ifreq(struct ifreq *ifr, void __user *arg)
3378 {
3379         size_t size = sizeof(*ifr);
3380 
3381         if (in_compat_syscall())
3382                 size = sizeof(struct compat_ifreq);
3383 
3384         if (copy_to_user(arg, ifr, size))
3385                 return -EFAULT;
3386 
3387         return 0;
3388 }
3389 EXPORT_SYMBOL(put_user_ifreq);
3390 
3391 #ifdef CONFIG_COMPAT
3392 static int compat_siocwandev(struct net *net, struct compat_ifreq __user *uifr32)
3393 {
3394         compat_uptr_t uptr32;
3395         struct ifreq ifr;
3396         void __user *saved;
3397         int err;
3398 
3399         if (get_user_ifreq(&ifr, NULL, uifr32))
3400                 return -EFAULT;
3401 
3402         if (get_user(uptr32, &uifr32->ifr_settings.ifs_ifsu))
3403                 return -EFAULT;
3404 
3405         saved = ifr.ifr_settings.ifs_ifsu.raw_hdlc;
3406         ifr.ifr_settings.ifs_ifsu.raw_hdlc = compat_ptr(uptr32);
3407 
3408         err = dev_ioctl(net, SIOCWANDEV, &ifr, NULL, NULL);
3409         if (!err) {
3410                 ifr.ifr_settings.ifs_ifsu.raw_hdlc = saved;
3411                 if (put_user_ifreq(&ifr, uifr32))
3412                         err = -EFAULT;
3413         }
3414         return err;
3415 }
3416 
3417 /* Handle ioctls that use ifreq::ifr_data and just need struct ifreq converted */
3418 static int compat_ifr_data_ioctl(struct net *net, unsigned int cmd,
3419                                  struct compat_ifreq __user *u_ifreq32)
3420 {
3421         struct ifreq ifreq;
3422         void __user *data;
3423 
3424         if (!is_socket_ioctl_cmd(cmd))
3425                 return -ENOTTY;
3426         if (get_user_ifreq(&ifreq, &data, u_ifreq32))
3427                 return -EFAULT;
3428         ifreq.ifr_data = data;
3429 
3430         return dev_ioctl(net, cmd, &ifreq, data, NULL);
3431 }
3432 
3433 static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
3434                          unsigned int cmd, unsigned long arg)
3435 {
3436         void __user *argp = compat_ptr(arg);
3437         struct sock *sk = sock->sk;
3438         struct net *net = sock_net(sk);
3439         const struct proto_ops *ops;
3440 
3441         if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))
3442                 return sock_ioctl(file, cmd, (unsigned long)argp);
3443 
3444         switch (cmd) {
3445         case SIOCWANDEV:
3446                 return compat_siocwandev(net, argp);
3447         case SIOCGSTAMP_OLD:
3448         case SIOCGSTAMPNS_OLD:
3449                 ops = READ_ONCE(sock->ops);
3450                 if (!ops->gettstamp)
3451                         return -ENOIOCTLCMD;
3452                 return ops->gettstamp(sock, argp, cmd == SIOCGSTAMP_OLD,
3453                                       !COMPAT_USE_64BIT_TIME);
3454 
3455         case SIOCETHTOOL:
3456         case SIOCBONDSLAVEINFOQUERY:
3457         case SIOCBONDINFOQUERY:
3458         case SIOCSHWTSTAMP:
3459         case SIOCGHWTSTAMP:
3460                 return compat_ifr_data_ioctl(net, cmd, argp);
3461 
3462         case FIOSETOWN:
3463         case SIOCSPGRP:
3464         case FIOGETOWN:
3465         case SIOCGPGRP:
3466         case SIOCBRADDBR:
3467         case SIOCBRDELBR:
3468         case SIOCGIFVLAN:
3469         case SIOCSIFVLAN:
3470         case SIOCGSKNS:
3471         case SIOCGSTAMP_NEW:
3472         case SIOCGSTAMPNS_NEW:
3473         case SIOCGIFCONF:
3474         case SIOCSIFBR:
3475         case SIOCGIFBR:
3476                 return sock_ioctl(file, cmd, arg);
3477 
3478         case SIOCGIFFLAGS:
3479         case SIOCSIFFLAGS:
3480         case SIOCGIFMAP:
3481         case SIOCSIFMAP:
3482         case SIOCGIFMETRIC:
3483         case SIOCSIFMETRIC:
3484         case SIOCGIFMTU:
3485         case SIOCSIFMTU:
3486         case SIOCGIFMEM:
3487         case SIOCSIFMEM:
3488         case SIOCGIFHWADDR:
3489         case SIOCSIFHWADDR:
3490         case SIOCADDMULTI:
3491         case SIOCDELMULTI:
3492         case SIOCGIFINDEX:
3493         case SIOCGIFADDR:
3494         case SIOCSIFADDR:
3495         case SIOCSIFHWBROADCAST:
3496         case SIOCDIFADDR:
3497         case SIOCGIFBRDADDR:
3498         case SIOCSIFBRDADDR:
3499         case SIOCGIFDSTADDR:
3500         case SIOCSIFDSTADDR:
3501         case SIOCGIFNETMASK:
3502         case SIOCSIFNETMASK:
3503         case SIOCSIFPFLAGS:
3504         case SIOCGIFPFLAGS:
3505         case SIOCGIFTXQLEN:
3506         case SIOCSIFTXQLEN:
3507         case SIOCBRADDIF:
3508         case SIOCBRDELIF:
3509         case SIOCGIFNAME:
3510         case SIOCSIFNAME:
3511         case SIOCGMIIPHY:
3512         case SIOCGMIIREG:
3513         case SIOCSMIIREG:
3514         case SIOCBONDENSLAVE:
3515         case SIOCBONDRELEASE:
3516         case SIOCBONDSETHWADDR:
3517         case SIOCBONDCHANGEACTIVE:
3518         case SIOCSARP:
3519         case SIOCGARP:
3520         case SIOCDARP:
3521         case SIOCOUTQ:
3522         case SIOCOUTQNSD:
3523         case SIOCATMARK:
3524                 return sock_do_ioctl(net, sock, cmd, arg);
3525         }
3526 
3527         return -ENOIOCTLCMD;
3528 }
3529 
3530 static long compat_sock_ioctl(struct file *file, unsigned int cmd,
3531                               unsigned long arg)
3532 {
3533         struct socket *sock = file->private_data;
3534         const struct proto_ops *ops = READ_ONCE(sock->ops);
3535         int ret = -ENOIOCTLCMD;
3536         struct sock *sk;
3537         struct net *net;
3538 
3539         sk = sock->sk;
3540         net = sock_net(sk);
3541 
3542         if (ops->compat_ioctl)
3543                 ret = ops->compat_ioctl(sock, cmd, arg);
3544 
3545         if (ret == -ENOIOCTLCMD &&
3546             (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
3547                 ret = compat_wext_handle_ioctl(net, cmd, arg);
3548 
3549         if (ret == -ENOIOCTLCMD)
3550                 ret = compat_sock_ioctl_trans(file, sock, cmd, arg);
3551 
3552         return ret;
3553 }
3554 #endif
3555 
3556 /**
3557  *      kernel_bind - bind an address to a socket (kernel space)
3558  *      @sock: socket
3559  *      @addr: address
3560  *      @addrlen: length of address
3561  *
3562  *      Returns 0 or an error.
3563  */
3564 
3565 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
3566 {
3567         struct sockaddr_storage address;
3568 
3569         memcpy(&address, addr, addrlen);
3570 
3571         return READ_ONCE(sock->ops)->bind(sock, (struct sockaddr *)&address,
3572                                           addrlen);
3573 }
3574 EXPORT_SYMBOL(kernel_bind);
3575 
3576 /**
3577  *      kernel_listen - move socket to listening state (kernel space)
3578  *      @sock: socket
3579  *      @backlog: pending connections queue size
3580  *
3581  *      Returns 0 or an error.
3582  */
3583 
3584 int kernel_listen(struct socket *sock, int backlog)
3585 {
3586         return READ_ONCE(sock->ops)->listen(sock, backlog);
3587 }
3588 EXPORT_SYMBOL(kernel_listen);
3589 
3590 /**
3591  *      kernel_accept - accept a connection (kernel space)
3592  *      @sock: listening socket
3593  *      @newsock: new connected socket
3594  *      @flags: flags
3595  *
3596  *      @flags must be SOCK_CLOEXEC, SOCK_NONBLOCK or 0.
3597  *      If it fails, @newsock is guaranteed to be %NULL.
3598  *      Returns 0 or an error.
3599  */
3600 
3601 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
3602 {
3603         struct sock *sk = sock->sk;
3604         const struct proto_ops *ops = READ_ONCE(sock->ops);
3605         struct proto_accept_arg arg = {
3606                 .flags = flags,
3607                 .kern = true,
3608         };
3609         int err;
3610 
3611         err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
3612                                newsock);
3613         if (err < 0)
3614                 goto done;
3615 
3616         err = ops->accept(sock, *newsock, &arg);
3617         if (err < 0) {
3618                 sock_release(*newsock);
3619                 *newsock = NULL;
3620                 goto done;
3621         }
3622 
3623         (*newsock)->ops = ops;
3624         __module_get(ops->owner);
3625 
3626 done:
3627         return err;
3628 }
3629 EXPORT_SYMBOL(kernel_accept);
3630 
3631 /**
3632  *      kernel_connect - connect a socket (kernel space)
3633  *      @sock: socket
3634  *      @addr: address
3635  *      @addrlen: address length
3636  *      @flags: flags (O_NONBLOCK, ...)
3637  *
3638  *      For datagram sockets, @addr is the address to which datagrams are sent
3639  *      by default, and the only address from which datagrams are received.
3640  *      For stream sockets, attempts to connect to @addr.
3641  *      Returns 0 or an error code.
3642  */
3643 
3644 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
3645                    int flags)
3646 {
3647         struct sockaddr_storage address;
3648 
3649         memcpy(&address, addr, addrlen);
3650 
3651         return READ_ONCE(sock->ops)->connect(sock, (struct sockaddr *)&address,
3652                                              addrlen, flags);
3653 }
3654 EXPORT_SYMBOL(kernel_connect);
3655 
3656 /**
3657  *      kernel_getsockname - get the address which the socket is bound (kernel space)
3658  *      @sock: socket
3659  *      @addr: address holder
3660  *
3661  *      Fills the @addr pointer with the address which the socket is bound.
3662  *      Returns the length of the address in bytes or an error code.
3663  */
3664 
3665 int kernel_getsockname(struct socket *sock, struct sockaddr *addr)
3666 {
3667         return READ_ONCE(sock->ops)->getname(sock, addr, 0);
3668 }
3669 EXPORT_SYMBOL(kernel_getsockname);
3670 
3671 /**
3672  *      kernel_getpeername - get the address which the socket is connected (kernel space)
3673  *      @sock: socket
3674  *      @addr: address holder
3675  *
3676  *      Fills the @addr pointer with the address which the socket is connected.
3677  *      Returns the length of the address in bytes or an error code.
3678  */
3679 
3680 int kernel_getpeername(struct socket *sock, struct sockaddr *addr)
3681 {
3682         return READ_ONCE(sock->ops)->getname(sock, addr, 1);
3683 }
3684 EXPORT_SYMBOL(kernel_getpeername);
3685 
3686 /**
3687  *      kernel_sock_shutdown - shut down part of a full-duplex connection (kernel space)
3688  *      @sock: socket
3689  *      @how: connection part
3690  *
3691  *      Returns 0 or an error.
3692  */
3693 
3694 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
3695 {
3696         return READ_ONCE(sock->ops)->shutdown(sock, how);
3697 }
3698 EXPORT_SYMBOL(kernel_sock_shutdown);
3699 
3700 /**
3701  *      kernel_sock_ip_overhead - returns the IP overhead imposed by a socket
3702  *      @sk: socket
3703  *
3704  *      This routine returns the IP overhead imposed by a socket i.e.
3705  *      the length of the underlying IP header, depending on whether
3706  *      this is an IPv4 or IPv6 socket and the length from IP options turned
3707  *      on at the socket. Assumes that the caller has a lock on the socket.
3708  */
3709 
3710 u32 kernel_sock_ip_overhead(struct sock *sk)
3711 {
3712         struct inet_sock *inet;
3713         struct ip_options_rcu *opt;
3714         u32 overhead = 0;
3715 #if IS_ENABLED(CONFIG_IPV6)
3716         struct ipv6_pinfo *np;
3717         struct ipv6_txoptions *optv6 = NULL;
3718 #endif /* IS_ENABLED(CONFIG_IPV6) */
3719 
3720         if (!sk)
3721                 return overhead;
3722 
3723         switch (sk->sk_family) {
3724         case AF_INET:
3725                 inet = inet_sk(sk);
3726                 overhead += sizeof(struct iphdr);
3727                 opt = rcu_dereference_protected(inet->inet_opt,
3728                                                 sock_owned_by_user(sk));
3729                 if (opt)
3730                         overhead += opt->opt.optlen;
3731                 return overhead;
3732 #if IS_ENABLED(CONFIG_IPV6)
3733         case AF_INET6:
3734                 np = inet6_sk(sk);
3735                 overhead += sizeof(struct ipv6hdr);
3736                 if (np)
3737                         optv6 = rcu_dereference_protected(np->opt,
3738                                                           sock_owned_by_user(sk));
3739                 if (optv6)
3740                         overhead += (optv6->opt_flen + optv6->opt_nflen);
3741                 return overhead;
3742 #endif /* IS_ENABLED(CONFIG_IPV6) */
3743         default: /* Returns 0 overhead if the socket is not ipv4 or ipv6 */
3744                 return overhead;
3745         }
3746 }
3747 EXPORT_SYMBOL(kernel_sock_ip_overhead);
3748 

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