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Linux/net/socket.c

  1 /*
  2  * NET          An implementation of the SOCKET network access protocol.
  3  *
  4  * Version:     @(#)socket.c    1.1.93  18/02/95
  5  *
  6  * Authors:     Orest Zborowski, <obz@Kodak.COM>
  7  *              Ross Biro
  8  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  9  *
 10  * Fixes:
 11  *              Anonymous       :       NOTSOCK/BADF cleanup. Error fix in
 12  *                                      shutdown()
 13  *              Alan Cox        :       verify_area() fixes
 14  *              Alan Cox        :       Removed DDI
 15  *              Jonathan Kamens :       SOCK_DGRAM reconnect bug
 16  *              Alan Cox        :       Moved a load of checks to the very
 17  *                                      top level.
 18  *              Alan Cox        :       Move address structures to/from user
 19  *                                      mode above the protocol layers.
 20  *              Rob Janssen     :       Allow 0 length sends.
 21  *              Alan Cox        :       Asynchronous I/O support (cribbed from the
 22  *                                      tty drivers).
 23  *              Niibe Yutaka    :       Asynchronous I/O for writes (4.4BSD style)
 24  *              Jeff Uphoff     :       Made max number of sockets command-line
 25  *                                      configurable.
 26  *              Matti Aarnio    :       Made the number of sockets dynamic,
 27  *                                      to be allocated when needed, and mr.
 28  *                                      Uphoff's max is used as max to be
 29  *                                      allowed to allocate.
 30  *              Linus           :       Argh. removed all the socket allocation
 31  *                                      altogether: it's in the inode now.
 32  *              Alan Cox        :       Made sock_alloc()/sock_release() public
 33  *                                      for NetROM and future kernel nfsd type
 34  *                                      stuff.
 35  *              Alan Cox        :       sendmsg/recvmsg basics.
 36  *              Tom Dyas        :       Export net symbols.
 37  *              Marcin Dalecki  :       Fixed problems with CONFIG_NET="n".
 38  *              Alan Cox        :       Added thread locking to sys_* calls
 39  *                                      for sockets. May have errors at the
 40  *                                      moment.
 41  *              Kevin Buhr      :       Fixed the dumb errors in the above.
 42  *              Andi Kleen      :       Some small cleanups, optimizations,
 43  *                                      and fixed a copy_from_user() bug.
 44  *              Tigran Aivazian :       sys_send(args) calls sys_sendto(args, NULL, 0)
 45  *              Tigran Aivazian :       Made listen(2) backlog sanity checks
 46  *                                      protocol-independent
 47  *
 48  *
 49  *              This program is free software; you can redistribute it and/or
 50  *              modify it under the terms of the GNU General Public License
 51  *              as published by the Free Software Foundation; either version
 52  *              2 of the License, or (at your option) any later version.
 53  *
 54  *
 55  *      This module is effectively the top level interface to the BSD socket
 56  *      paradigm.
 57  *
 58  *      Based upon Swansea University Computer Society NET3.039
 59  */
 60 
 61 #include <linux/mm.h>
 62 #include <linux/socket.h>
 63 #include <linux/file.h>
 64 #include <linux/net.h>
 65 #include <linux/interrupt.h>
 66 #include <linux/thread_info.h>
 67 #include <linux/rcupdate.h>
 68 #include <linux/netdevice.h>
 69 #include <linux/proc_fs.h>
 70 #include <linux/seq_file.h>
 71 #include <linux/mutex.h>
 72 #include <linux/if_bridge.h>
 73 #include <linux/if_frad.h>
 74 #include <linux/if_vlan.h>
 75 #include <linux/ptp_classify.h>
 76 #include <linux/init.h>
 77 #include <linux/poll.h>
 78 #include <linux/cache.h>
 79 #include <linux/module.h>
 80 #include <linux/highmem.h>
 81 #include <linux/mount.h>
 82 #include <linux/security.h>
 83 #include <linux/syscalls.h>
 84 #include <linux/compat.h>
 85 #include <linux/kmod.h>
 86 #include <linux/audit.h>
 87 #include <linux/wireless.h>
 88 #include <linux/nsproxy.h>
 89 #include <linux/magic.h>
 90 #include <linux/slab.h>
 91 #include <linux/xattr.h>
 92 
 93 #include <asm/uaccess.h>
 94 #include <asm/unistd.h>
 95 
 96 #include <net/compat.h>
 97 #include <net/wext.h>
 98 #include <net/cls_cgroup.h>
 99 
100 #include <net/sock.h>
101 #include <linux/netfilter.h>
102 
103 #include <linux/if_tun.h>
104 #include <linux/ipv6_route.h>
105 #include <linux/route.h>
106 #include <linux/sockios.h>
107 #include <linux/atalk.h>
108 #include <net/busy_poll.h>
109 #include <linux/errqueue.h>
110 
111 #ifdef CONFIG_NET_RX_BUSY_POLL
112 unsigned int sysctl_net_busy_read __read_mostly;
113 unsigned int sysctl_net_busy_poll __read_mostly;
114 #endif
115 
116 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to);
117 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
118 static int sock_mmap(struct file *file, struct vm_area_struct *vma);
119 
120 static int sock_close(struct inode *inode, struct file *file);
121 static unsigned int sock_poll(struct file *file,
122                               struct poll_table_struct *wait);
123 static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
124 #ifdef CONFIG_COMPAT
125 static long compat_sock_ioctl(struct file *file,
126                               unsigned int cmd, unsigned long arg);
127 #endif
128 static int sock_fasync(int fd, struct file *filp, int on);
129 static ssize_t sock_sendpage(struct file *file, struct page *page,
130                              int offset, size_t size, loff_t *ppos, int more);
131 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
132                                 struct pipe_inode_info *pipe, size_t len,
133                                 unsigned int flags);
134 
135 /*
136  *      Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
137  *      in the operation structures but are done directly via the socketcall() multiplexor.
138  */
139 
140 static const struct file_operations socket_file_ops = {
141         .owner =        THIS_MODULE,
142         .llseek =       no_llseek,
143         .read_iter =    sock_read_iter,
144         .write_iter =   sock_write_iter,
145         .poll =         sock_poll,
146         .unlocked_ioctl = sock_ioctl,
147 #ifdef CONFIG_COMPAT
148         .compat_ioctl = compat_sock_ioctl,
149 #endif
150         .mmap =         sock_mmap,
151         .release =      sock_close,
152         .fasync =       sock_fasync,
153         .sendpage =     sock_sendpage,
154         .splice_write = generic_splice_sendpage,
155         .splice_read =  sock_splice_read,
156 };
157 
158 /*
159  *      The protocol list. Each protocol is registered in here.
160  */
161 
162 static DEFINE_SPINLOCK(net_family_lock);
163 static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
164 
165 /*
166  *      Statistics counters of the socket lists
167  */
168 
169 static DEFINE_PER_CPU(int, sockets_in_use);
170 
171 /*
172  * Support routines.
173  * Move socket addresses back and forth across the kernel/user
174  * divide and look after the messy bits.
175  */
176 
177 /**
178  *      move_addr_to_kernel     -       copy a socket address into kernel space
179  *      @uaddr: Address in user space
180  *      @kaddr: Address in kernel space
181  *      @ulen: Length in user space
182  *
183  *      The address is copied into kernel space. If the provided address is
184  *      too long an error code of -EINVAL is returned. If the copy gives
185  *      invalid addresses -EFAULT is returned. On a success 0 is returned.
186  */
187 
188 int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
189 {
190         if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
191                 return -EINVAL;
192         if (ulen == 0)
193                 return 0;
194         if (copy_from_user(kaddr, uaddr, ulen))
195                 return -EFAULT;
196         return audit_sockaddr(ulen, kaddr);
197 }
198 
199 /**
200  *      move_addr_to_user       -       copy an address to user space
201  *      @kaddr: kernel space address
202  *      @klen: length of address in kernel
203  *      @uaddr: user space address
204  *      @ulen: pointer to user length field
205  *
206  *      The value pointed to by ulen on entry is the buffer length available.
207  *      This is overwritten with the buffer space used. -EINVAL is returned
208  *      if an overlong buffer is specified or a negative buffer size. -EFAULT
209  *      is returned if either the buffer or the length field are not
210  *      accessible.
211  *      After copying the data up to the limit the user specifies, the true
212  *      length of the data is written over the length limit the user
213  *      specified. Zero is returned for a success.
214  */
215 
216 static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
217                              void __user *uaddr, int __user *ulen)
218 {
219         int err;
220         int len;
221 
222         BUG_ON(klen > sizeof(struct sockaddr_storage));
223         err = get_user(len, ulen);
224         if (err)
225                 return err;
226         if (len > klen)
227                 len = klen;
228         if (len < 0)
229                 return -EINVAL;
230         if (len) {
231                 if (audit_sockaddr(klen, kaddr))
232                         return -ENOMEM;
233                 if (copy_to_user(uaddr, kaddr, len))
234                         return -EFAULT;
235         }
236         /*
237          *      "fromlen shall refer to the value before truncation.."
238          *                      1003.1g
239          */
240         return __put_user(klen, ulen);
241 }
242 
243 static struct kmem_cache *sock_inode_cachep __read_mostly;
244 
245 static struct inode *sock_alloc_inode(struct super_block *sb)
246 {
247         struct socket_alloc *ei;
248         struct socket_wq *wq;
249 
250         ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
251         if (!ei)
252                 return NULL;
253         wq = kmalloc(sizeof(*wq), GFP_KERNEL);
254         if (!wq) {
255                 kmem_cache_free(sock_inode_cachep, ei);
256                 return NULL;
257         }
258         init_waitqueue_head(&wq->wait);
259         wq->fasync_list = NULL;
260         wq->flags = 0;
261         RCU_INIT_POINTER(ei->socket.wq, wq);
262 
263         ei->socket.state = SS_UNCONNECTED;
264         ei->socket.flags = 0;
265         ei->socket.ops = NULL;
266         ei->socket.sk = NULL;
267         ei->socket.file = NULL;
268 
269         return &ei->vfs_inode;
270 }
271 
272 static void sock_destroy_inode(struct inode *inode)
273 {
274         struct socket_alloc *ei;
275         struct socket_wq *wq;
276 
277         ei = container_of(inode, struct socket_alloc, vfs_inode);
278         wq = rcu_dereference_protected(ei->socket.wq, 1);
279         kfree_rcu(wq, rcu);
280         kmem_cache_free(sock_inode_cachep, ei);
281 }
282 
283 static void init_once(void *foo)
284 {
285         struct socket_alloc *ei = (struct socket_alloc *)foo;
286 
287         inode_init_once(&ei->vfs_inode);
288 }
289 
290 static int init_inodecache(void)
291 {
292         sock_inode_cachep = kmem_cache_create("sock_inode_cache",
293                                               sizeof(struct socket_alloc),
294                                               0,
295                                               (SLAB_HWCACHE_ALIGN |
296                                                SLAB_RECLAIM_ACCOUNT |
297                                                SLAB_MEM_SPREAD | SLAB_ACCOUNT),
298                                               init_once);
299         if (sock_inode_cachep == NULL)
300                 return -ENOMEM;
301         return 0;
302 }
303 
304 static const struct super_operations sockfs_ops = {
305         .alloc_inode    = sock_alloc_inode,
306         .destroy_inode  = sock_destroy_inode,
307         .statfs         = simple_statfs,
308 };
309 
310 /*
311  * sockfs_dname() is called from d_path().
312  */
313 static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
314 {
315         return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",
316                                 d_inode(dentry)->i_ino);
317 }
318 
319 static const struct dentry_operations sockfs_dentry_operations = {
320         .d_dname  = sockfs_dname,
321 };
322 
323 static struct dentry *sockfs_mount(struct file_system_type *fs_type,
324                          int flags, const char *dev_name, void *data)
325 {
326         return mount_pseudo(fs_type, "socket:", &sockfs_ops,
327                 &sockfs_dentry_operations, SOCKFS_MAGIC);
328 }
329 
330 static struct vfsmount *sock_mnt __read_mostly;
331 
332 static struct file_system_type sock_fs_type = {
333         .name =         "sockfs",
334         .mount =        sockfs_mount,
335         .kill_sb =      kill_anon_super,
336 };
337 
338 /*
339  *      Obtains the first available file descriptor and sets it up for use.
340  *
341  *      These functions create file structures and maps them to fd space
342  *      of the current process. On success it returns file descriptor
343  *      and file struct implicitly stored in sock->file.
344  *      Note that another thread may close file descriptor before we return
345  *      from this function. We use the fact that now we do not refer
346  *      to socket after mapping. If one day we will need it, this
347  *      function will increment ref. count on file by 1.
348  *
349  *      In any case returned fd MAY BE not valid!
350  *      This race condition is unavoidable
351  *      with shared fd spaces, we cannot solve it inside kernel,
352  *      but we take care of internal coherence yet.
353  */
354 
355 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
356 {
357         struct qstr name = { .name = "" };
358         struct path path;
359         struct file *file;
360 
361         if (dname) {
362                 name.name = dname;
363                 name.len = strlen(name.name);
364         } else if (sock->sk) {
365                 name.name = sock->sk->sk_prot_creator->name;
366                 name.len = strlen(name.name);
367         }
368         path.dentry = d_alloc_pseudo(sock_mnt->mnt_sb, &name);
369         if (unlikely(!path.dentry))
370                 return ERR_PTR(-ENOMEM);
371         path.mnt = mntget(sock_mnt);
372 
373         d_instantiate(path.dentry, SOCK_INODE(sock));
374 
375         file = alloc_file(&path, FMODE_READ | FMODE_WRITE,
376                   &socket_file_ops);
377         if (IS_ERR(file)) {
378                 /* drop dentry, keep inode */
379                 ihold(d_inode(path.dentry));
380                 path_put(&path);
381                 return file;
382         }
383 
384         sock->file = file;
385         file->f_flags = O_RDWR | (flags & O_NONBLOCK);
386         file->private_data = sock;
387         return file;
388 }
389 EXPORT_SYMBOL(sock_alloc_file);
390 
391 static int sock_map_fd(struct socket *sock, int flags)
392 {
393         struct file *newfile;
394         int fd = get_unused_fd_flags(flags);
395         if (unlikely(fd < 0))
396                 return fd;
397 
398         newfile = sock_alloc_file(sock, flags, NULL);
399         if (likely(!IS_ERR(newfile))) {
400                 fd_install(fd, newfile);
401                 return fd;
402         }
403 
404         put_unused_fd(fd);
405         return PTR_ERR(newfile);
406 }
407 
408 struct socket *sock_from_file(struct file *file, int *err)
409 {
410         if (file->f_op == &socket_file_ops)
411                 return file->private_data;      /* set in sock_map_fd */
412 
413         *err = -ENOTSOCK;
414         return NULL;
415 }
416 EXPORT_SYMBOL(sock_from_file);
417 
418 /**
419  *      sockfd_lookup - Go from a file number to its socket slot
420  *      @fd: file handle
421  *      @err: pointer to an error code return
422  *
423  *      The file handle passed in is locked and the socket it is bound
424  *      too is returned. If an error occurs the err pointer is overwritten
425  *      with a negative errno code and NULL is returned. The function checks
426  *      for both invalid handles and passing a handle which is not a socket.
427  *
428  *      On a success the socket object pointer is returned.
429  */
430 
431 struct socket *sockfd_lookup(int fd, int *err)
432 {
433         struct file *file;
434         struct socket *sock;
435 
436         file = fget(fd);
437         if (!file) {
438                 *err = -EBADF;
439                 return NULL;
440         }
441 
442         sock = sock_from_file(file, err);
443         if (!sock)
444                 fput(file);
445         return sock;
446 }
447 EXPORT_SYMBOL(sockfd_lookup);
448 
449 static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
450 {
451         struct fd f = fdget(fd);
452         struct socket *sock;
453 
454         *err = -EBADF;
455         if (f.file) {
456                 sock = sock_from_file(f.file, err);
457                 if (likely(sock)) {
458                         *fput_needed = f.flags;
459                         return sock;
460                 }
461                 fdput(f);
462         }
463         return NULL;
464 }
465 
466 #define XATTR_SOCKPROTONAME_SUFFIX "sockprotoname"
467 #define XATTR_NAME_SOCKPROTONAME (XATTR_SYSTEM_PREFIX XATTR_SOCKPROTONAME_SUFFIX)
468 #define XATTR_NAME_SOCKPROTONAME_LEN (sizeof(XATTR_NAME_SOCKPROTONAME)-1)
469 static ssize_t sockfs_getxattr(struct dentry *dentry, struct inode *inode,
470                                const char *name, void *value, size_t size)
471 {
472         const char *proto_name;
473         size_t proto_size;
474         int error;
475 
476         error = -ENODATA;
477         if (!strncmp(name, XATTR_NAME_SOCKPROTONAME, XATTR_NAME_SOCKPROTONAME_LEN)) {
478                 proto_name = dentry->d_name.name;
479                 proto_size = strlen(proto_name);
480 
481                 if (value) {
482                         error = -ERANGE;
483                         if (proto_size + 1 > size)
484                                 goto out;
485 
486                         strncpy(value, proto_name, proto_size + 1);
487                 }
488                 error = proto_size + 1;
489         }
490 
491 out:
492         return error;
493 }
494 
495 static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
496                                 size_t size)
497 {
498         ssize_t len;
499         ssize_t used = 0;
500 
501         len = security_inode_listsecurity(d_inode(dentry), buffer, size);
502         if (len < 0)
503                 return len;
504         used += len;
505         if (buffer) {
506                 if (size < used)
507                         return -ERANGE;
508                 buffer += len;
509         }
510 
511         len = (XATTR_NAME_SOCKPROTONAME_LEN + 1);
512         used += len;
513         if (buffer) {
514                 if (size < used)
515                         return -ERANGE;
516                 memcpy(buffer, XATTR_NAME_SOCKPROTONAME, len);
517                 buffer += len;
518         }
519 
520         return used;
521 }
522 
523 static const struct inode_operations sockfs_inode_ops = {
524         .getxattr = sockfs_getxattr,
525         .listxattr = sockfs_listxattr,
526 };
527 
528 /**
529  *      sock_alloc      -       allocate a socket
530  *
531  *      Allocate a new inode and socket object. The two are bound together
532  *      and initialised. The socket is then returned. If we are out of inodes
533  *      NULL is returned.
534  */
535 
536 struct socket *sock_alloc(void)
537 {
538         struct inode *inode;
539         struct socket *sock;
540 
541         inode = new_inode_pseudo(sock_mnt->mnt_sb);
542         if (!inode)
543                 return NULL;
544 
545         sock = SOCKET_I(inode);
546 
547         kmemcheck_annotate_bitfield(sock, type);
548         inode->i_ino = get_next_ino();
549         inode->i_mode = S_IFSOCK | S_IRWXUGO;
550         inode->i_uid = current_fsuid();
551         inode->i_gid = current_fsgid();
552         inode->i_op = &sockfs_inode_ops;
553 
554         this_cpu_add(sockets_in_use, 1);
555         return sock;
556 }
557 EXPORT_SYMBOL(sock_alloc);
558 
559 /**
560  *      sock_release    -       close a socket
561  *      @sock: socket to close
562  *
563  *      The socket is released from the protocol stack if it has a release
564  *      callback, and the inode is then released if the socket is bound to
565  *      an inode not a file.
566  */
567 
568 void sock_release(struct socket *sock)
569 {
570         if (sock->ops) {
571                 struct module *owner = sock->ops->owner;
572 
573                 sock->ops->release(sock);
574                 sock->ops = NULL;
575                 module_put(owner);
576         }
577 
578         if (rcu_dereference_protected(sock->wq, 1)->fasync_list)
579                 pr_err("%s: fasync list not empty!\n", __func__);
580 
581         this_cpu_sub(sockets_in_use, 1);
582         if (!sock->file) {
583                 iput(SOCK_INODE(sock));
584                 return;
585         }
586         sock->file = NULL;
587 }
588 EXPORT_SYMBOL(sock_release);
589 
590 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
591 {
592         u8 flags = *tx_flags;
593 
594         if (tsflags & SOF_TIMESTAMPING_TX_HARDWARE)
595                 flags |= SKBTX_HW_TSTAMP;
596 
597         if (tsflags & SOF_TIMESTAMPING_TX_SOFTWARE)
598                 flags |= SKBTX_SW_TSTAMP;
599 
600         if (tsflags & SOF_TIMESTAMPING_TX_SCHED)
601                 flags |= SKBTX_SCHED_TSTAMP;
602 
603         *tx_flags = flags;
604 }
605 EXPORT_SYMBOL(__sock_tx_timestamp);
606 
607 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
608 {
609         int ret = sock->ops->sendmsg(sock, msg, msg_data_left(msg));
610         BUG_ON(ret == -EIOCBQUEUED);
611         return ret;
612 }
613 
614 int sock_sendmsg(struct socket *sock, struct msghdr *msg)
615 {
616         int err = security_socket_sendmsg(sock, msg,
617                                           msg_data_left(msg));
618 
619         return err ?: sock_sendmsg_nosec(sock, msg);
620 }
621 EXPORT_SYMBOL(sock_sendmsg);
622 
623 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
624                    struct kvec *vec, size_t num, size_t size)
625 {
626         iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
627         return sock_sendmsg(sock, msg);
628 }
629 EXPORT_SYMBOL(kernel_sendmsg);
630 
631 /*
632  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
633  */
634 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
635         struct sk_buff *skb)
636 {
637         int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
638         struct scm_timestamping tss;
639         int empty = 1;
640         struct skb_shared_hwtstamps *shhwtstamps =
641                 skb_hwtstamps(skb);
642 
643         /* Race occurred between timestamp enabling and packet
644            receiving.  Fill in the current time for now. */
645         if (need_software_tstamp && skb->tstamp.tv64 == 0)
646                 __net_timestamp(skb);
647 
648         if (need_software_tstamp) {
649                 if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
650                         struct timeval tv;
651                         skb_get_timestamp(skb, &tv);
652                         put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP,
653                                  sizeof(tv), &tv);
654                 } else {
655                         struct timespec ts;
656                         skb_get_timestampns(skb, &ts);
657                         put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPNS,
658                                  sizeof(ts), &ts);
659                 }
660         }
661 
662         memset(&tss, 0, sizeof(tss));
663         if ((sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
664             ktime_to_timespec_cond(skb->tstamp, tss.ts + 0))
665                 empty = 0;
666         if (shhwtstamps &&
667             (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
668             ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2))
669                 empty = 0;
670         if (!empty)
671                 put_cmsg(msg, SOL_SOCKET,
672                          SCM_TIMESTAMPING, sizeof(tss), &tss);
673 }
674 EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
675 
676 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
677         struct sk_buff *skb)
678 {
679         int ack;
680 
681         if (!sock_flag(sk, SOCK_WIFI_STATUS))
682                 return;
683         if (!skb->wifi_acked_valid)
684                 return;
685 
686         ack = skb->wifi_acked;
687 
688         put_cmsg(msg, SOL_SOCKET, SCM_WIFI_STATUS, sizeof(ack), &ack);
689 }
690 EXPORT_SYMBOL_GPL(__sock_recv_wifi_status);
691 
692 static inline void sock_recv_drops(struct msghdr *msg, struct sock *sk,
693                                    struct sk_buff *skb)
694 {
695         if (sock_flag(sk, SOCK_RXQ_OVFL) && skb && SOCK_SKB_CB(skb)->dropcount)
696                 put_cmsg(msg, SOL_SOCKET, SO_RXQ_OVFL,
697                         sizeof(__u32), &SOCK_SKB_CB(skb)->dropcount);
698 }
699 
700 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
701         struct sk_buff *skb)
702 {
703         sock_recv_timestamp(msg, sk, skb);
704         sock_recv_drops(msg, sk, skb);
705 }
706 EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops);
707 
708 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
709                                      int flags)
710 {
711         return sock->ops->recvmsg(sock, msg, msg_data_left(msg), flags);
712 }
713 
714 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
715 {
716         int err = security_socket_recvmsg(sock, msg, msg_data_left(msg), flags);
717 
718         return err ?: sock_recvmsg_nosec(sock, msg, flags);
719 }
720 EXPORT_SYMBOL(sock_recvmsg);
721 
722 /**
723  * kernel_recvmsg - Receive a message from a socket (kernel space)
724  * @sock:       The socket to receive the message from
725  * @msg:        Received message
726  * @vec:        Input s/g array for message data
727  * @num:        Size of input s/g array
728  * @size:       Number of bytes to read
729  * @flags:      Message flags (MSG_DONTWAIT, etc...)
730  *
731  * On return the msg structure contains the scatter/gather array passed in the
732  * vec argument. The array is modified so that it consists of the unfilled
733  * portion of the original array.
734  *
735  * The returned value is the total number of bytes received, or an error.
736  */
737 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
738                    struct kvec *vec, size_t num, size_t size, int flags)
739 {
740         mm_segment_t oldfs = get_fs();
741         int result;
742 
743         iov_iter_kvec(&msg->msg_iter, READ | ITER_KVEC, vec, num, size);
744         set_fs(KERNEL_DS);
745         result = sock_recvmsg(sock, msg, flags);
746         set_fs(oldfs);
747         return result;
748 }
749 EXPORT_SYMBOL(kernel_recvmsg);
750 
751 static ssize_t sock_sendpage(struct file *file, struct page *page,
752                              int offset, size_t size, loff_t *ppos, int more)
753 {
754         struct socket *sock;
755         int flags;
756 
757         sock = file->private_data;
758 
759         flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
760         /* more is a combination of MSG_MORE and MSG_SENDPAGE_NOTLAST */
761         flags |= more;
762 
763         return kernel_sendpage(sock, page, offset, size, flags);
764 }
765 
766 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
767                                 struct pipe_inode_info *pipe, size_t len,
768                                 unsigned int flags)
769 {
770         struct socket *sock = file->private_data;
771 
772         if (unlikely(!sock->ops->splice_read))
773                 return -EINVAL;
774 
775         return sock->ops->splice_read(sock, ppos, pipe, len, flags);
776 }
777 
778 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
779 {
780         struct file *file = iocb->ki_filp;
781         struct socket *sock = file->private_data;
782         struct msghdr msg = {.msg_iter = *to,
783                              .msg_iocb = iocb};
784         ssize_t res;
785 
786         if (file->f_flags & O_NONBLOCK)
787                 msg.msg_flags = MSG_DONTWAIT;
788 
789         if (iocb->ki_pos != 0)
790                 return -ESPIPE;
791 
792         if (!iov_iter_count(to))        /* Match SYS5 behaviour */
793                 return 0;
794 
795         res = sock_recvmsg(sock, &msg, msg.msg_flags);
796         *to = msg.msg_iter;
797         return res;
798 }
799 
800 static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
801 {
802         struct file *file = iocb->ki_filp;
803         struct socket *sock = file->private_data;
804         struct msghdr msg = {.msg_iter = *from,
805                              .msg_iocb = iocb};
806         ssize_t res;
807 
808         if (iocb->ki_pos != 0)
809                 return -ESPIPE;
810 
811         if (file->f_flags & O_NONBLOCK)
812                 msg.msg_flags = MSG_DONTWAIT;
813 
814         if (sock->type == SOCK_SEQPACKET)
815                 msg.msg_flags |= MSG_EOR;
816 
817         res = sock_sendmsg(sock, &msg);
818         *from = msg.msg_iter;
819         return res;
820 }
821 
822 /*
823  * Atomic setting of ioctl hooks to avoid race
824  * with module unload.
825  */
826 
827 static DEFINE_MUTEX(br_ioctl_mutex);
828 static int (*br_ioctl_hook) (struct net *, unsigned int cmd, void __user *arg);
829 
830 void brioctl_set(int (*hook) (struct net *, unsigned int, void __user *))
831 {
832         mutex_lock(&br_ioctl_mutex);
833         br_ioctl_hook = hook;
834         mutex_unlock(&br_ioctl_mutex);
835 }
836 EXPORT_SYMBOL(brioctl_set);
837 
838 static DEFINE_MUTEX(vlan_ioctl_mutex);
839 static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
840 
841 void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
842 {
843         mutex_lock(&vlan_ioctl_mutex);
844         vlan_ioctl_hook = hook;
845         mutex_unlock(&vlan_ioctl_mutex);
846 }
847 EXPORT_SYMBOL(vlan_ioctl_set);
848 
849 static DEFINE_MUTEX(dlci_ioctl_mutex);
850 static int (*dlci_ioctl_hook) (unsigned int, void __user *);
851 
852 void dlci_ioctl_set(int (*hook) (unsigned int, void __user *))
853 {
854         mutex_lock(&dlci_ioctl_mutex);
855         dlci_ioctl_hook = hook;
856         mutex_unlock(&dlci_ioctl_mutex);
857 }
858 EXPORT_SYMBOL(dlci_ioctl_set);
859 
860 static long sock_do_ioctl(struct net *net, struct socket *sock,
861                                  unsigned int cmd, unsigned long arg)
862 {
863         int err;
864         void __user *argp = (void __user *)arg;
865 
866         err = sock->ops->ioctl(sock, cmd, arg);
867 
868         /*
869          * If this ioctl is unknown try to hand it down
870          * to the NIC driver.
871          */
872         if (err == -ENOIOCTLCMD)
873                 err = dev_ioctl(net, cmd, argp);
874 
875         return err;
876 }
877 
878 /*
879  *      With an ioctl, arg may well be a user mode pointer, but we don't know
880  *      what to do with it - that's up to the protocol still.
881  */
882 
883 static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
884 {
885         struct socket *sock;
886         struct sock *sk;
887         void __user *argp = (void __user *)arg;
888         int pid, err;
889         struct net *net;
890 
891         sock = file->private_data;
892         sk = sock->sk;
893         net = sock_net(sk);
894         if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15)) {
895                 err = dev_ioctl(net, cmd, argp);
896         } else
897 #ifdef CONFIG_WEXT_CORE
898         if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
899                 err = dev_ioctl(net, cmd, argp);
900         } else
901 #endif
902                 switch (cmd) {
903                 case FIOSETOWN:
904                 case SIOCSPGRP:
905                         err = -EFAULT;
906                         if (get_user(pid, (int __user *)argp))
907                                 break;
908                         f_setown(sock->file, pid, 1);
909                         err = 0;
910                         break;
911                 case FIOGETOWN:
912                 case SIOCGPGRP:
913                         err = put_user(f_getown(sock->file),
914                                        (int __user *)argp);
915                         break;
916                 case SIOCGIFBR:
917                 case SIOCSIFBR:
918                 case SIOCBRADDBR:
919                 case SIOCBRDELBR:
920                         err = -ENOPKG;
921                         if (!br_ioctl_hook)
922                                 request_module("bridge");
923 
924                         mutex_lock(&br_ioctl_mutex);
925                         if (br_ioctl_hook)
926                                 err = br_ioctl_hook(net, cmd, argp);
927                         mutex_unlock(&br_ioctl_mutex);
928                         break;
929                 case SIOCGIFVLAN:
930                 case SIOCSIFVLAN:
931                         err = -ENOPKG;
932                         if (!vlan_ioctl_hook)
933                                 request_module("8021q");
934 
935                         mutex_lock(&vlan_ioctl_mutex);
936                         if (vlan_ioctl_hook)
937                                 err = vlan_ioctl_hook(net, argp);
938                         mutex_unlock(&vlan_ioctl_mutex);
939                         break;
940                 case SIOCADDDLCI:
941                 case SIOCDELDLCI:
942                         err = -ENOPKG;
943                         if (!dlci_ioctl_hook)
944                                 request_module("dlci");
945 
946                         mutex_lock(&dlci_ioctl_mutex);
947                         if (dlci_ioctl_hook)
948                                 err = dlci_ioctl_hook(cmd, argp);
949                         mutex_unlock(&dlci_ioctl_mutex);
950                         break;
951                 default:
952                         err = sock_do_ioctl(net, sock, cmd, arg);
953                         break;
954                 }
955         return err;
956 }
957 
958 int sock_create_lite(int family, int type, int protocol, struct socket **res)
959 {
960         int err;
961         struct socket *sock = NULL;
962 
963         err = security_socket_create(family, type, protocol, 1);
964         if (err)
965                 goto out;
966 
967         sock = sock_alloc();
968         if (!sock) {
969                 err = -ENOMEM;
970                 goto out;
971         }
972 
973         sock->type = type;
974         err = security_socket_post_create(sock, family, type, protocol, 1);
975         if (err)
976                 goto out_release;
977 
978 out:
979         *res = sock;
980         return err;
981 out_release:
982         sock_release(sock);
983         sock = NULL;
984         goto out;
985 }
986 EXPORT_SYMBOL(sock_create_lite);
987 
988 /* No kernel lock held - perfect */
989 static unsigned int sock_poll(struct file *file, poll_table *wait)
990 {
991         unsigned int busy_flag = 0;
992         struct socket *sock;
993 
994         /*
995          *      We can't return errors to poll, so it's either yes or no.
996          */
997         sock = file->private_data;
998 
999         if (sk_can_busy_loop(sock->sk)) {
1000                 /* this socket can poll_ll so tell the system call */
1001                 busy_flag = POLL_BUSY_LOOP;
1002 
1003                 /* once, only if requested by syscall */
1004                 if (wait && (wait->_key & POLL_BUSY_LOOP))
1005                         sk_busy_loop(sock->sk, 1);
1006         }
1007 
1008         return busy_flag | sock->ops->poll(file, sock, wait);
1009 }
1010 
1011 static int sock_mmap(struct file *file, struct vm_area_struct *vma)
1012 {
1013         struct socket *sock = file->private_data;
1014 
1015         return sock->ops->mmap(file, sock, vma);
1016 }
1017 
1018 static int sock_close(struct inode *inode, struct file *filp)
1019 {
1020         sock_release(SOCKET_I(inode));
1021         return 0;
1022 }
1023 
1024 /*
1025  *      Update the socket async list
1026  *
1027  *      Fasync_list locking strategy.
1028  *
1029  *      1. fasync_list is modified only under process context socket lock
1030  *         i.e. under semaphore.
1031  *      2. fasync_list is used under read_lock(&sk->sk_callback_lock)
1032  *         or under socket lock
1033  */
1034 
1035 static int sock_fasync(int fd, struct file *filp, int on)
1036 {
1037         struct socket *sock = filp->private_data;
1038         struct sock *sk = sock->sk;
1039         struct socket_wq *wq;
1040 
1041         if (sk == NULL)
1042                 return -EINVAL;
1043 
1044         lock_sock(sk);
1045         wq = rcu_dereference_protected(sock->wq, lockdep_sock_is_held(sk));
1046         fasync_helper(fd, filp, on, &wq->fasync_list);
1047 
1048         if (!wq->fasync_list)
1049                 sock_reset_flag(sk, SOCK_FASYNC);
1050         else
1051                 sock_set_flag(sk, SOCK_FASYNC);
1052 
1053         release_sock(sk);
1054         return 0;
1055 }
1056 
1057 /* This function may be called only under rcu_lock */
1058 
1059 int sock_wake_async(struct socket_wq *wq, int how, int band)
1060 {
1061         if (!wq || !wq->fasync_list)
1062                 return -1;
1063 
1064         switch (how) {
1065         case SOCK_WAKE_WAITD:
1066                 if (test_bit(SOCKWQ_ASYNC_WAITDATA, &wq->flags))
1067                         break;
1068                 goto call_kill;
1069         case SOCK_WAKE_SPACE:
1070                 if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags))
1071                         break;
1072                 /* fall through */
1073         case SOCK_WAKE_IO:
1074 call_kill:
1075                 kill_fasync(&wq->fasync_list, SIGIO, band);
1076                 break;
1077         case SOCK_WAKE_URG:
1078                 kill_fasync(&wq->fasync_list, SIGURG, band);
1079         }
1080 
1081         return 0;
1082 }
1083 EXPORT_SYMBOL(sock_wake_async);
1084 
1085 int __sock_create(struct net *net, int family, int type, int protocol,
1086                          struct socket **res, int kern)
1087 {
1088         int err;
1089         struct socket *sock;
1090         const struct net_proto_family *pf;
1091 
1092         /*
1093          *      Check protocol is in range
1094          */
1095         if (family < 0 || family >= NPROTO)
1096                 return -EAFNOSUPPORT;
1097         if (type < 0 || type >= SOCK_MAX)
1098                 return -EINVAL;
1099 
1100         /* Compatibility.
1101 
1102            This uglymoron is moved from INET layer to here to avoid
1103            deadlock in module load.
1104          */
1105         if (family == PF_INET && type == SOCK_PACKET) {
1106                 pr_info_once("%s uses obsolete (PF_INET,SOCK_PACKET)\n",
1107                              current->comm);
1108                 family = PF_PACKET;
1109         }
1110 
1111         err = security_socket_create(family, type, protocol, kern);
1112         if (err)
1113                 return err;
1114 
1115         /*
1116          *      Allocate the socket and allow the family to set things up. if
1117          *      the protocol is 0, the family is instructed to select an appropriate
1118          *      default.
1119          */
1120         sock = sock_alloc();
1121         if (!sock) {
1122                 net_warn_ratelimited("socket: no more sockets\n");
1123                 return -ENFILE; /* Not exactly a match, but its the
1124                                    closest posix thing */
1125         }
1126 
1127         sock->type = type;
1128 
1129 #ifdef CONFIG_MODULES
1130         /* Attempt to load a protocol module if the find failed.
1131          *
1132          * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
1133          * requested real, full-featured networking support upon configuration.
1134          * Otherwise module support will break!
1135          */
1136         if (rcu_access_pointer(net_families[family]) == NULL)
1137                 request_module("net-pf-%d", family);
1138 #endif
1139 
1140         rcu_read_lock();
1141         pf = rcu_dereference(net_families[family]);
1142         err = -EAFNOSUPPORT;
1143         if (!pf)
1144                 goto out_release;
1145 
1146         /*
1147          * We will call the ->create function, that possibly is in a loadable
1148          * module, so we have to bump that loadable module refcnt first.
1149          */
1150         if (!try_module_get(pf->owner))
1151                 goto out_release;
1152 
1153         /* Now protected by module ref count */
1154         rcu_read_unlock();
1155 
1156         err = pf->create(net, sock, protocol, kern);
1157         if (err < 0)
1158                 goto out_module_put;
1159 
1160         /*
1161          * Now to bump the refcnt of the [loadable] module that owns this
1162          * socket at sock_release time we decrement its refcnt.
1163          */
1164         if (!try_module_get(sock->ops->owner))
1165                 goto out_module_busy;
1166 
1167         /*
1168          * Now that we're done with the ->create function, the [loadable]
1169          * module can have its refcnt decremented
1170          */
1171         module_put(pf->owner);
1172         err = security_socket_post_create(sock, family, type, protocol, kern);
1173         if (err)
1174                 goto out_sock_release;
1175         *res = sock;
1176 
1177         return 0;
1178 
1179 out_module_busy:
1180         err = -EAFNOSUPPORT;
1181 out_module_put:
1182         sock->ops = NULL;
1183         module_put(pf->owner);
1184 out_sock_release:
1185         sock_release(sock);
1186         return err;
1187 
1188 out_release:
1189         rcu_read_unlock();
1190         goto out_sock_release;
1191 }
1192 EXPORT_SYMBOL(__sock_create);
1193 
1194 int sock_create(int family, int type, int protocol, struct socket **res)
1195 {
1196         return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
1197 }
1198 EXPORT_SYMBOL(sock_create);
1199 
1200 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
1201 {
1202         return __sock_create(net, family, type, protocol, res, 1);
1203 }
1204 EXPORT_SYMBOL(sock_create_kern);
1205 
1206 SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
1207 {
1208         int retval;
1209         struct socket *sock;
1210         int flags;
1211 
1212         /* Check the SOCK_* constants for consistency.  */
1213         BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
1214         BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
1215         BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
1216         BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
1217 
1218         flags = type & ~SOCK_TYPE_MASK;
1219         if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1220                 return -EINVAL;
1221         type &= SOCK_TYPE_MASK;
1222 
1223         if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1224                 flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1225 
1226         retval = sock_create(family, type, protocol, &sock);
1227         if (retval < 0)
1228                 goto out;
1229 
1230         retval = sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
1231         if (retval < 0)
1232                 goto out_release;
1233 
1234 out:
1235         /* It may be already another descriptor 8) Not kernel problem. */
1236         return retval;
1237 
1238 out_release:
1239         sock_release(sock);
1240         return retval;
1241 }
1242 
1243 /*
1244  *      Create a pair of connected sockets.
1245  */
1246 
1247 SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
1248                 int __user *, usockvec)
1249 {
1250         struct socket *sock1, *sock2;
1251         int fd1, fd2, err;
1252         struct file *newfile1, *newfile2;
1253         int flags;
1254 
1255         flags = type & ~SOCK_TYPE_MASK;
1256         if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1257                 return -EINVAL;
1258         type &= SOCK_TYPE_MASK;
1259 
1260         if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1261                 flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1262 
1263         /*
1264          * Obtain the first socket and check if the underlying protocol
1265          * supports the socketpair call.
1266          */
1267 
1268         err = sock_create(family, type, protocol, &sock1);
1269         if (err < 0)
1270                 goto out;
1271 
1272         err = sock_create(family, type, protocol, &sock2);
1273         if (err < 0)
1274                 goto out_release_1;
1275 
1276         err = sock1->ops->socketpair(sock1, sock2);
1277         if (err < 0)
1278                 goto out_release_both;
1279 
1280         fd1 = get_unused_fd_flags(flags);
1281         if (unlikely(fd1 < 0)) {
1282                 err = fd1;
1283                 goto out_release_both;
1284         }
1285 
1286         fd2 = get_unused_fd_flags(flags);
1287         if (unlikely(fd2 < 0)) {
1288                 err = fd2;
1289                 goto out_put_unused_1;
1290         }
1291 
1292         newfile1 = sock_alloc_file(sock1, flags, NULL);
1293         if (IS_ERR(newfile1)) {
1294                 err = PTR_ERR(newfile1);
1295                 goto out_put_unused_both;
1296         }
1297 
1298         newfile2 = sock_alloc_file(sock2, flags, NULL);
1299         if (IS_ERR(newfile2)) {
1300                 err = PTR_ERR(newfile2);
1301                 goto out_fput_1;
1302         }
1303 
1304         err = put_user(fd1, &usockvec[0]);
1305         if (err)
1306                 goto out_fput_both;
1307 
1308         err = put_user(fd2, &usockvec[1]);
1309         if (err)
1310                 goto out_fput_both;
1311 
1312         audit_fd_pair(fd1, fd2);
1313 
1314         fd_install(fd1, newfile1);
1315         fd_install(fd2, newfile2);
1316         /* fd1 and fd2 may be already another descriptors.
1317          * Not kernel problem.
1318          */
1319 
1320         return 0;
1321 
1322 out_fput_both:
1323         fput(newfile2);
1324         fput(newfile1);
1325         put_unused_fd(fd2);
1326         put_unused_fd(fd1);
1327         goto out;
1328 
1329 out_fput_1:
1330         fput(newfile1);
1331         put_unused_fd(fd2);
1332         put_unused_fd(fd1);
1333         sock_release(sock2);
1334         goto out;
1335 
1336 out_put_unused_both:
1337         put_unused_fd(fd2);
1338 out_put_unused_1:
1339         put_unused_fd(fd1);
1340 out_release_both:
1341         sock_release(sock2);
1342 out_release_1:
1343         sock_release(sock1);
1344 out:
1345         return err;
1346 }
1347 
1348 /*
1349  *      Bind a name to a socket. Nothing much to do here since it's
1350  *      the protocol's responsibility to handle the local address.
1351  *
1352  *      We move the socket address to kernel space before we call
1353  *      the protocol layer (having also checked the address is ok).
1354  */
1355 
1356 SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
1357 {
1358         struct socket *sock;
1359         struct sockaddr_storage address;
1360         int err, fput_needed;
1361 
1362         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1363         if (sock) {
1364                 err = move_addr_to_kernel(umyaddr, addrlen, &address);
1365                 if (err >= 0) {
1366                         err = security_socket_bind(sock,
1367                                                    (struct sockaddr *)&address,
1368                                                    addrlen);
1369                         if (!err)
1370                                 err = sock->ops->bind(sock,
1371                                                       (struct sockaddr *)
1372                                                       &address, addrlen);
1373                 }
1374                 fput_light(sock->file, fput_needed);
1375         }
1376         return err;
1377 }
1378 
1379 /*
1380  *      Perform a listen. Basically, we allow the protocol to do anything
1381  *      necessary for a listen, and if that works, we mark the socket as
1382  *      ready for listening.
1383  */
1384 
1385 SYSCALL_DEFINE2(listen, int, fd, int, backlog)
1386 {
1387         struct socket *sock;
1388         int err, fput_needed;
1389         int somaxconn;
1390 
1391         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1392         if (sock) {
1393                 somaxconn = sock_net(sock->sk)->core.sysctl_somaxconn;
1394                 if ((unsigned int)backlog > somaxconn)
1395                         backlog = somaxconn;
1396 
1397                 err = security_socket_listen(sock, backlog);
1398                 if (!err)
1399                         err = sock->ops->listen(sock, backlog);
1400 
1401                 fput_light(sock->file, fput_needed);
1402         }
1403         return err;
1404 }
1405 
1406 /*
1407  *      For accept, we attempt to create a new socket, set up the link
1408  *      with the client, wake up the client, then return the new
1409  *      connected fd. We collect the address of the connector in kernel
1410  *      space and move it to user at the very end. This is unclean because
1411  *      we open the socket then return an error.
1412  *
1413  *      1003.1g adds the ability to recvmsg() to query connection pending
1414  *      status to recvmsg. We need to add that support in a way thats
1415  *      clean when we restucture accept also.
1416  */
1417 
1418 SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
1419                 int __user *, upeer_addrlen, int, flags)
1420 {
1421         struct socket *sock, *newsock;
1422         struct file *newfile;
1423         int err, len, newfd, fput_needed;
1424         struct sockaddr_storage address;
1425 
1426         if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
1427                 return -EINVAL;
1428 
1429         if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
1430                 flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
1431 
1432         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1433         if (!sock)
1434                 goto out;
1435 
1436         err = -ENFILE;
1437         newsock = sock_alloc();
1438         if (!newsock)
1439                 goto out_put;
1440 
1441         newsock->type = sock->type;
1442         newsock->ops = sock->ops;
1443 
1444         /*
1445          * We don't need try_module_get here, as the listening socket (sock)
1446          * has the protocol module (sock->ops->owner) held.
1447          */
1448         __module_get(newsock->ops->owner);
1449 
1450         newfd = get_unused_fd_flags(flags);
1451         if (unlikely(newfd < 0)) {
1452                 err = newfd;
1453                 sock_release(newsock);
1454                 goto out_put;
1455         }
1456         newfile = sock_alloc_file(newsock, flags, sock->sk->sk_prot_creator->name);
1457         if (IS_ERR(newfile)) {
1458                 err = PTR_ERR(newfile);
1459                 put_unused_fd(newfd);
1460                 sock_release(newsock);
1461                 goto out_put;
1462         }
1463 
1464         err = security_socket_accept(sock, newsock);
1465         if (err)
1466                 goto out_fd;
1467 
1468         err = sock->ops->accept(sock, newsock, sock->file->f_flags);
1469         if (err < 0)
1470                 goto out_fd;
1471 
1472         if (upeer_sockaddr) {
1473                 if (newsock->ops->getname(newsock, (struct sockaddr *)&address,
1474                                           &len, 2) < 0) {
1475                         err = -ECONNABORTED;
1476                         goto out_fd;
1477                 }
1478                 err = move_addr_to_user(&address,
1479                                         len, upeer_sockaddr, upeer_addrlen);
1480                 if (err < 0)
1481                         goto out_fd;
1482         }
1483 
1484         /* File flags are not inherited via accept() unlike another OSes. */
1485 
1486         fd_install(newfd, newfile);
1487         err = newfd;
1488 
1489 out_put:
1490         fput_light(sock->file, fput_needed);
1491 out:
1492         return err;
1493 out_fd:
1494         fput(newfile);
1495         put_unused_fd(newfd);
1496         goto out_put;
1497 }
1498 
1499 SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
1500                 int __user *, upeer_addrlen)
1501 {
1502         return sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
1503 }
1504 
1505 /*
1506  *      Attempt to connect to a socket with the server address.  The address
1507  *      is in user space so we verify it is OK and move it to kernel space.
1508  *
1509  *      For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
1510  *      break bindings
1511  *
1512  *      NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
1513  *      other SEQPACKET protocols that take time to connect() as it doesn't
1514  *      include the -EINPROGRESS status for such sockets.
1515  */
1516 
1517 SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
1518                 int, addrlen)
1519 {
1520         struct socket *sock;
1521         struct sockaddr_storage address;
1522         int err, fput_needed;
1523 
1524         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1525         if (!sock)
1526                 goto out;
1527         err = move_addr_to_kernel(uservaddr, addrlen, &address);
1528         if (err < 0)
1529                 goto out_put;
1530 
1531         err =
1532             security_socket_connect(sock, (struct sockaddr *)&address, addrlen);
1533         if (err)
1534                 goto out_put;
1535 
1536         err = sock->ops->connect(sock, (struct sockaddr *)&address, addrlen,
1537                                  sock->file->f_flags);
1538 out_put:
1539         fput_light(sock->file, fput_needed);
1540 out:
1541         return err;
1542 }
1543 
1544 /*
1545  *      Get the local address ('name') of a socket object. Move the obtained
1546  *      name to user space.
1547  */
1548 
1549 SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
1550                 int __user *, usockaddr_len)
1551 {
1552         struct socket *sock;
1553         struct sockaddr_storage address;
1554         int len, err, fput_needed;
1555 
1556         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1557         if (!sock)
1558                 goto out;
1559 
1560         err = security_socket_getsockname(sock);
1561         if (err)
1562                 goto out_put;
1563 
1564         err = sock->ops->getname(sock, (struct sockaddr *)&address, &len, 0);
1565         if (err)
1566                 goto out_put;
1567         err = move_addr_to_user(&address, len, usockaddr, usockaddr_len);
1568 
1569 out_put:
1570         fput_light(sock->file, fput_needed);
1571 out:
1572         return err;
1573 }
1574 
1575 /*
1576  *      Get the remote address ('name') of a socket object. Move the obtained
1577  *      name to user space.
1578  */
1579 
1580 SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
1581                 int __user *, usockaddr_len)
1582 {
1583         struct socket *sock;
1584         struct sockaddr_storage address;
1585         int len, err, fput_needed;
1586 
1587         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1588         if (sock != NULL) {
1589                 err = security_socket_getpeername(sock);
1590                 if (err) {
1591                         fput_light(sock->file, fput_needed);
1592                         return err;
1593                 }
1594 
1595                 err =
1596                     sock->ops->getname(sock, (struct sockaddr *)&address, &len,
1597                                        1);
1598                 if (!err)
1599                         err = move_addr_to_user(&address, len, usockaddr,
1600                                                 usockaddr_len);
1601                 fput_light(sock->file, fput_needed);
1602         }
1603         return err;
1604 }
1605 
1606 /*
1607  *      Send a datagram to a given address. We move the address into kernel
1608  *      space and check the user space data area is readable before invoking
1609  *      the protocol.
1610  */
1611 
1612 SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
1613                 unsigned int, flags, struct sockaddr __user *, addr,
1614                 int, addr_len)
1615 {
1616         struct socket *sock;
1617         struct sockaddr_storage address;
1618         int err;
1619         struct msghdr msg;
1620         struct iovec iov;
1621         int fput_needed;
1622 
1623         err = import_single_range(WRITE, buff, len, &iov, &msg.msg_iter);
1624         if (unlikely(err))
1625                 return err;
1626         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1627         if (!sock)
1628                 goto out;
1629 
1630         msg.msg_name = NULL;
1631         msg.msg_control = NULL;
1632         msg.msg_controllen = 0;
1633         msg.msg_namelen = 0;
1634         if (addr) {
1635                 err = move_addr_to_kernel(addr, addr_len, &address);
1636                 if (err < 0)
1637                         goto out_put;
1638                 msg.msg_name = (struct sockaddr *)&address;
1639                 msg.msg_namelen = addr_len;
1640         }
1641         if (sock->file->f_flags & O_NONBLOCK)
1642                 flags |= MSG_DONTWAIT;
1643         msg.msg_flags = flags;
1644         err = sock_sendmsg(sock, &msg);
1645 
1646 out_put:
1647         fput_light(sock->file, fput_needed);
1648 out:
1649         return err;
1650 }
1651 
1652 /*
1653  *      Send a datagram down a socket.
1654  */
1655 
1656 SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
1657                 unsigned int, flags)
1658 {
1659         return sys_sendto(fd, buff, len, flags, NULL, 0);
1660 }
1661 
1662 /*
1663  *      Receive a frame from the socket and optionally record the address of the
1664  *      sender. We verify the buffers are writable and if needed move the
1665  *      sender address from kernel to user space.
1666  */
1667 
1668 SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
1669                 unsigned int, flags, struct sockaddr __user *, addr,
1670                 int __user *, addr_len)
1671 {
1672         struct socket *sock;
1673         struct iovec iov;
1674         struct msghdr msg;
1675         struct sockaddr_storage address;
1676         int err, err2;
1677         int fput_needed;
1678 
1679         err = import_single_range(READ, ubuf, size, &iov, &msg.msg_iter);
1680         if (unlikely(err))
1681                 return err;
1682         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1683         if (!sock)
1684                 goto out;
1685 
1686         msg.msg_control = NULL;
1687         msg.msg_controllen = 0;
1688         /* Save some cycles and don't copy the address if not needed */
1689         msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
1690         /* We assume all kernel code knows the size of sockaddr_storage */
1691         msg.msg_namelen = 0;
1692         msg.msg_iocb = NULL;
1693         if (sock->file->f_flags & O_NONBLOCK)
1694                 flags |= MSG_DONTWAIT;
1695         err = sock_recvmsg(sock, &msg, flags);
1696 
1697         if (err >= 0 && addr != NULL) {
1698                 err2 = move_addr_to_user(&address,
1699                                          msg.msg_namelen, addr, addr_len);
1700                 if (err2 < 0)
1701                         err = err2;
1702         }
1703 
1704         fput_light(sock->file, fput_needed);
1705 out:
1706         return err;
1707 }
1708 
1709 /*
1710  *      Receive a datagram from a socket.
1711  */
1712 
1713 SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
1714                 unsigned int, flags)
1715 {
1716         return sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
1717 }
1718 
1719 /*
1720  *      Set a socket option. Because we don't know the option lengths we have
1721  *      to pass the user mode parameter for the protocols to sort out.
1722  */
1723 
1724 SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
1725                 char __user *, optval, int, optlen)
1726 {
1727         int err, fput_needed;
1728         struct socket *sock;
1729 
1730         if (optlen < 0)
1731                 return -EINVAL;
1732 
1733         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1734         if (sock != NULL) {
1735                 err = security_socket_setsockopt(sock, level, optname);
1736                 if (err)
1737                         goto out_put;
1738 
1739                 if (level == SOL_SOCKET)
1740                         err =
1741                             sock_setsockopt(sock, level, optname, optval,
1742                                             optlen);
1743                 else
1744                         err =
1745                             sock->ops->setsockopt(sock, level, optname, optval,
1746                                                   optlen);
1747 out_put:
1748                 fput_light(sock->file, fput_needed);
1749         }
1750         return err;
1751 }
1752 
1753 /*
1754  *      Get a socket option. Because we don't know the option lengths we have
1755  *      to pass a user mode parameter for the protocols to sort out.
1756  */
1757 
1758 SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
1759                 char __user *, optval, int __user *, optlen)
1760 {
1761         int err, fput_needed;
1762         struct socket *sock;
1763 
1764         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1765         if (sock != NULL) {
1766                 err = security_socket_getsockopt(sock, level, optname);
1767                 if (err)
1768                         goto out_put;
1769 
1770                 if (level == SOL_SOCKET)
1771                         err =
1772                             sock_getsockopt(sock, level, optname, optval,
1773                                             optlen);
1774                 else
1775                         err =
1776                             sock->ops->getsockopt(sock, level, optname, optval,
1777                                                   optlen);
1778 out_put:
1779                 fput_light(sock->file, fput_needed);
1780         }
1781         return err;
1782 }
1783 
1784 /*
1785  *      Shutdown a socket.
1786  */
1787 
1788 SYSCALL_DEFINE2(shutdown, int, fd, int, how)
1789 {
1790         int err, fput_needed;
1791         struct socket *sock;
1792 
1793         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1794         if (sock != NULL) {
1795                 err = security_socket_shutdown(sock, how);
1796                 if (!err)
1797                         err = sock->ops->shutdown(sock, how);
1798                 fput_light(sock->file, fput_needed);
1799         }
1800         return err;
1801 }
1802 
1803 /* A couple of helpful macros for getting the address of the 32/64 bit
1804  * fields which are the same type (int / unsigned) on our platforms.
1805  */
1806 #define COMPAT_MSG(msg, member) ((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
1807 #define COMPAT_NAMELEN(msg)     COMPAT_MSG(msg, msg_namelen)
1808 #define COMPAT_FLAGS(msg)       COMPAT_MSG(msg, msg_flags)
1809 
1810 struct used_address {
1811         struct sockaddr_storage name;
1812         unsigned int name_len;
1813 };
1814 
1815 static int copy_msghdr_from_user(struct msghdr *kmsg,
1816                                  struct user_msghdr __user *umsg,
1817                                  struct sockaddr __user **save_addr,
1818                                  struct iovec **iov)
1819 {
1820         struct sockaddr __user *uaddr;
1821         struct iovec __user *uiov;
1822         size_t nr_segs;
1823         ssize_t err;
1824 
1825         if (!access_ok(VERIFY_READ, umsg, sizeof(*umsg)) ||
1826             __get_user(uaddr, &umsg->msg_name) ||
1827             __get_user(kmsg->msg_namelen, &umsg->msg_namelen) ||
1828             __get_user(uiov, &umsg->msg_iov) ||
1829             __get_user(nr_segs, &umsg->msg_iovlen) ||
1830             __get_user(kmsg->msg_control, &umsg->msg_control) ||
1831             __get_user(kmsg->msg_controllen, &umsg->msg_controllen) ||
1832             __get_user(kmsg->msg_flags, &umsg->msg_flags))
1833                 return -EFAULT;
1834 
1835         if (!uaddr)
1836                 kmsg->msg_namelen = 0;
1837 
1838         if (kmsg->msg_namelen < 0)
1839                 return -EINVAL;
1840 
1841         if (kmsg->msg_namelen > sizeof(struct sockaddr_storage))
1842                 kmsg->msg_namelen = sizeof(struct sockaddr_storage);
1843 
1844         if (save_addr)
1845                 *save_addr = uaddr;
1846 
1847         if (uaddr && kmsg->msg_namelen) {
1848                 if (!save_addr) {
1849                         err = move_addr_to_kernel(uaddr, kmsg->msg_namelen,
1850                                                   kmsg->msg_name);
1851                         if (err < 0)
1852                                 return err;
1853                 }
1854         } else {
1855                 kmsg->msg_name = NULL;
1856                 kmsg->msg_namelen = 0;
1857         }
1858 
1859         if (nr_segs > UIO_MAXIOV)
1860                 return -EMSGSIZE;
1861 
1862         kmsg->msg_iocb = NULL;
1863 
1864         return import_iovec(save_addr ? READ : WRITE, uiov, nr_segs,
1865                             UIO_FASTIOV, iov, &kmsg->msg_iter);
1866 }
1867 
1868 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
1869                          struct msghdr *msg_sys, unsigned int flags,
1870                          struct used_address *used_address,
1871                          unsigned int allowed_msghdr_flags)
1872 {
1873         struct compat_msghdr __user *msg_compat =
1874             (struct compat_msghdr __user *)msg;
1875         struct sockaddr_storage address;
1876         struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
1877         unsigned char ctl[sizeof(struct cmsghdr) + 20]
1878             __attribute__ ((aligned(sizeof(__kernel_size_t))));
1879         /* 20 is size of ipv6_pktinfo */
1880         unsigned char *ctl_buf = ctl;
1881         int ctl_len;
1882         ssize_t err;
1883 
1884         msg_sys->msg_name = &address;
1885 
1886         if (MSG_CMSG_COMPAT & flags)
1887                 err = get_compat_msghdr(msg_sys, msg_compat, NULL, &iov);
1888         else
1889                 err = copy_msghdr_from_user(msg_sys, msg, NULL, &iov);
1890         if (err < 0)
1891                 return err;
1892 
1893         err = -ENOBUFS;
1894 
1895         if (msg_sys->msg_controllen > INT_MAX)
1896                 goto out_freeiov;
1897         flags |= (msg_sys->msg_flags & allowed_msghdr_flags);
1898         ctl_len = msg_sys->msg_controllen;
1899         if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
1900                 err =
1901                     cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl,
1902                                                      sizeof(ctl));
1903                 if (err)
1904                         goto out_freeiov;
1905                 ctl_buf = msg_sys->msg_control;
1906                 ctl_len = msg_sys->msg_controllen;
1907         } else if (ctl_len) {
1908                 if (ctl_len > sizeof(ctl)) {
1909                         ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
1910                         if (ctl_buf == NULL)
1911                                 goto out_freeiov;
1912                 }
1913                 err = -EFAULT;
1914                 /*
1915                  * Careful! Before this, msg_sys->msg_control contains a user pointer.
1916                  * Afterwards, it will be a kernel pointer. Thus the compiler-assisted
1917                  * checking falls down on this.
1918                  */
1919                 if (copy_from_user(ctl_buf,
1920                                    (void __user __force *)msg_sys->msg_control,
1921                                    ctl_len))
1922                         goto out_freectl;
1923                 msg_sys->msg_control = ctl_buf;
1924         }
1925         msg_sys->msg_flags = flags;
1926 
1927         if (sock->file->f_flags & O_NONBLOCK)
1928                 msg_sys->msg_flags |= MSG_DONTWAIT;
1929         /*
1930          * If this is sendmmsg() and current destination address is same as
1931          * previously succeeded address, omit asking LSM's decision.
1932          * used_address->name_len is initialized to UINT_MAX so that the first
1933          * destination address never matches.
1934          */
1935         if (used_address && msg_sys->msg_name &&
1936             used_address->name_len == msg_sys->msg_namelen &&
1937             !memcmp(&used_address->name, msg_sys->msg_name,
1938                     used_address->name_len)) {
1939                 err = sock_sendmsg_nosec(sock, msg_sys);
1940                 goto out_freectl;
1941         }
1942         err = sock_sendmsg(sock, msg_sys);
1943         /*
1944          * If this is sendmmsg() and sending to current destination address was
1945          * successful, remember it.
1946          */
1947         if (used_address && err >= 0) {
1948                 used_address->name_len = msg_sys->msg_namelen;
1949                 if (msg_sys->msg_name)
1950                         memcpy(&used_address->name, msg_sys->msg_name,
1951                                used_address->name_len);
1952         }
1953 
1954 out_freectl:
1955         if (ctl_buf != ctl)
1956                 sock_kfree_s(sock->sk, ctl_buf, ctl_len);
1957 out_freeiov:
1958         kfree(iov);
1959         return err;
1960 }
1961 
1962 /*
1963  *      BSD sendmsg interface
1964  */
1965 
1966 long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned flags)
1967 {
1968         int fput_needed, err;
1969         struct msghdr msg_sys;
1970         struct socket *sock;
1971 
1972         sock = sockfd_lookup_light(fd, &err, &fput_needed);
1973         if (!sock)
1974                 goto out;
1975 
1976         err = ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL, 0);
1977 
1978         fput_light(sock->file, fput_needed);
1979 out:
1980         return err;
1981 }
1982 
1983 SYSCALL_DEFINE3(sendmsg, int, fd, struct user_msghdr __user *, msg, unsigned int, flags)
1984 {
1985         if (flags & MSG_CMSG_COMPAT)
1986                 return -EINVAL;
1987         return __sys_sendmsg(fd, msg, flags);
1988 }
1989 
1990 /*
1991  *      Linux sendmmsg interface
1992  */
1993 
1994 int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
1995                    unsigned int flags)
1996 {
1997         int fput_needed, err, datagrams;
1998         struct socket *sock;
1999         struct mmsghdr __user *entry;
2000         struct compat_mmsghdr __user *compat_entry;
2001         struct msghdr msg_sys;
2002         struct used_address used_address;
2003         unsigned int oflags = flags;
2004 
2005         if (vlen > UIO_MAXIOV)
2006                 vlen = UIO_MAXIOV;
2007 
2008         datagrams = 0;
2009 
2010         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2011         if (!sock)
2012                 return err;
2013 
2014         used_address.name_len = UINT_MAX;
2015         entry = mmsg;
2016         compat_entry = (struct compat_mmsghdr __user *)mmsg;
2017         err = 0;
2018         flags |= MSG_BATCH;
2019 
2020         while (datagrams < vlen) {
2021                 if (datagrams == vlen - 1)
2022                         flags = oflags;
2023 
2024                 if (MSG_CMSG_COMPAT & flags) {
2025                         err = ___sys_sendmsg(sock, (struct user_msghdr __user *)compat_entry,
2026                                              &msg_sys, flags, &used_address, MSG_EOR);
2027                         if (err < 0)
2028                                 break;
2029                         err = __put_user(err, &compat_entry->msg_len);
2030                         ++compat_entry;
2031                 } else {
2032                         err = ___sys_sendmsg(sock,
2033                                              (struct user_msghdr __user *)entry,
2034                                              &msg_sys, flags, &used_address, MSG_EOR);
2035                         if (err < 0)
2036                                 break;
2037                         err = put_user(err, &entry->msg_len);
2038                         ++entry;
2039                 }
2040 
2041                 if (err)
2042                         break;
2043                 ++datagrams;
2044                 cond_resched();
2045         }
2046 
2047         fput_light(sock->file, fput_needed);
2048 
2049         /* We only return an error if no datagrams were able to be sent */
2050         if (datagrams != 0)
2051                 return datagrams;
2052 
2053         return err;
2054 }
2055 
2056 SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg,
2057                 unsigned int, vlen, unsigned int, flags)
2058 {
2059         if (flags & MSG_CMSG_COMPAT)
2060                 return -EINVAL;
2061         return __sys_sendmmsg(fd, mmsg, vlen, flags);
2062 }
2063 
2064 static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
2065                          struct msghdr *msg_sys, unsigned int flags, int nosec)
2066 {
2067         struct compat_msghdr __user *msg_compat =
2068             (struct compat_msghdr __user *)msg;
2069         struct iovec iovstack[UIO_FASTIOV];
2070         struct iovec *iov = iovstack;
2071         unsigned long cmsg_ptr;
2072         int len;
2073         ssize_t err;
2074 
2075         /* kernel mode address */
2076         struct sockaddr_storage addr;
2077 
2078         /* user mode address pointers */
2079         struct sockaddr __user *uaddr;
2080         int __user *uaddr_len = COMPAT_NAMELEN(msg);
2081 
2082         msg_sys->msg_name = &addr;
2083 
2084         if (MSG_CMSG_COMPAT & flags)
2085                 err = get_compat_msghdr(msg_sys, msg_compat, &uaddr, &iov);
2086         else
2087                 err = copy_msghdr_from_user(msg_sys, msg, &uaddr, &iov);
2088         if (err < 0)
2089                 return err;
2090 
2091         cmsg_ptr = (unsigned long)msg_sys->msg_control;
2092         msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
2093 
2094         /* We assume all kernel code knows the size of sockaddr_storage */
2095         msg_sys->msg_namelen = 0;
2096 
2097         if (sock->file->f_flags & O_NONBLOCK)
2098                 flags |= MSG_DONTWAIT;
2099         err = (nosec ? sock_recvmsg_nosec : sock_recvmsg)(sock, msg_sys, flags);
2100         if (err < 0)
2101                 goto out_freeiov;
2102         len = err;
2103 
2104         if (uaddr != NULL) {
2105                 err = move_addr_to_user(&addr,
2106                                         msg_sys->msg_namelen, uaddr,
2107                                         uaddr_len);
2108                 if (err < 0)
2109                         goto out_freeiov;
2110         }
2111         err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT),
2112                          COMPAT_FLAGS(msg));
2113         if (err)
2114                 goto out_freeiov;
2115         if (MSG_CMSG_COMPAT & flags)
2116                 err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2117                                  &msg_compat->msg_controllen);
2118         else
2119                 err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr,
2120                                  &msg->msg_controllen);
2121         if (err)
2122                 goto out_freeiov;
2123         err = len;
2124 
2125 out_freeiov:
2126         kfree(iov);
2127         return err;
2128 }
2129 
2130 /*
2131  *      BSD recvmsg interface
2132  */
2133 
2134 long __sys_recvmsg(int fd, struct user_msghdr __user *msg, unsigned flags)
2135 {
2136         int fput_needed, err;
2137         struct msghdr msg_sys;
2138         struct socket *sock;
2139 
2140         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2141         if (!sock)
2142                 goto out;
2143 
2144         err = ___sys_recvmsg(sock, msg, &msg_sys, flags, 0);
2145 
2146         fput_light(sock->file, fput_needed);
2147 out:
2148         return err;
2149 }
2150 
2151 SYSCALL_DEFINE3(recvmsg, int, fd, struct user_msghdr __user *, msg,
2152                 unsigned int, flags)
2153 {
2154         if (flags & MSG_CMSG_COMPAT)
2155                 return -EINVAL;
2156         return __sys_recvmsg(fd, msg, flags);
2157 }
2158 
2159 /*
2160  *     Linux recvmmsg interface
2161  */
2162 
2163 int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen,
2164                    unsigned int flags, struct timespec *timeout)
2165 {
2166         int fput_needed, err, datagrams;
2167         struct socket *sock;
2168         struct mmsghdr __user *entry;
2169         struct compat_mmsghdr __user *compat_entry;
2170         struct msghdr msg_sys;
2171         struct timespec64 end_time;
2172         struct timespec64 timeout64;
2173 
2174         if (timeout &&
2175             poll_select_set_timeout(&end_time, timeout->tv_sec,
2176                                     timeout->tv_nsec))
2177                 return -EINVAL;
2178 
2179         datagrams = 0;
2180 
2181         sock = sockfd_lookup_light(fd, &err, &fput_needed);
2182         if (!sock)
2183                 return err;
2184 
2185         err = sock_error(sock->sk);
2186         if (err)
2187                 goto out_put;
2188 
2189         entry = mmsg;
2190         compat_entry = (struct compat_mmsghdr __user *)mmsg;
2191 
2192         while (datagrams < vlen) {
2193                 /*
2194                  * No need to ask LSM for more than the first datagram.
2195                  */
2196                 if (MSG_CMSG_COMPAT & flags) {
2197                         err = ___sys_recvmsg(sock, (struct user_msghdr __user *)compat_entry,
2198                                              &msg_sys, flags & ~MSG_WAITFORONE,
2199                                              datagrams);
2200                         if (err < 0)
2201                                 break;
2202                         err = __put_user(err, &compat_entry->msg_len);
2203                         ++compat_entry;
2204                 } else {
2205                         err = ___sys_recvmsg(sock,
2206                                              (struct user_msghdr __user *)entry,
2207                                              &msg_sys, flags & ~MSG_WAITFORONE,
2208                                              datagrams);
2209                         if (err < 0)
2210                                 break;
2211                         err = put_user(err, &entry->msg_len);
2212                         ++entry;
2213                 }
2214 
2215                 if (err)
2216                         break;
2217                 ++datagrams;
2218 
2219                 /* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */
2220                 if (flags & MSG_WAITFORONE)
2221                         flags |= MSG_DONTWAIT;
2222 
2223                 if (timeout) {
2224                         ktime_get_ts64(&timeout64);
2225                         *timeout = timespec64_to_timespec(
2226                                         timespec64_sub(end_time, timeout64));
2227                         if (timeout->tv_sec < 0) {
2228                                 timeout->tv_sec = timeout->tv_nsec = 0;
2229                                 break;
2230                         }
2231 
2232                         /* Timeout, return less than vlen datagrams */
2233                         if (timeout->tv_nsec == 0 && timeout->tv_sec == 0)
2234                                 break;
2235                 }
2236 
2237                 /* Out of band data, return right away */
2238                 if (msg_sys.msg_flags & MSG_OOB)
2239                         break;
2240                 cond_resched();
2241         }
2242 
2243         if (err == 0)
2244                 goto out_put;
2245 
2246         if (datagrams == 0) {
2247                 datagrams = err;
2248                 goto out_put;
2249         }
2250 
2251         /*
2252          * We may return less entries than requested (vlen) if the
2253          * sock is non block and there aren't enough datagrams...
2254          */
2255         if (err != -EAGAIN) {
2256                 /*
2257                  * ... or  if recvmsg returns an error after we
2258                  * received some datagrams, where we record the
2259                  * error to return on the next call or if the
2260                  * app asks about it using getsockopt(SO_ERROR).
2261                  */
2262                 sock->sk->sk_err = -err;
2263         }
2264 out_put:
2265         fput_light(sock->file, fput_needed);
2266 
2267         return datagrams;
2268 }
2269 
2270 SYSCALL_DEFINE5(recvmmsg, int, fd, struct mmsghdr __user *, mmsg,
2271                 unsigned int, vlen, unsigned int, flags,
2272                 struct timespec __user *, timeout)
2273 {
2274         int datagrams;
2275         struct timespec timeout_sys;
2276 
2277         if (flags & MSG_CMSG_COMPAT)
2278                 return -EINVAL;
2279 
2280         if (!timeout)
2281                 return __sys_recvmmsg(fd, mmsg, vlen, flags, NULL);
2282 
2283         if (copy_from_user(&timeout_sys, timeout, sizeof(timeout_sys)))
2284                 return -EFAULT;
2285 
2286         datagrams = __sys_recvmmsg(fd, mmsg, vlen, flags, &timeout_sys);
2287 
2288         if (datagrams > 0 &&
2289             copy_to_user(timeout, &timeout_sys, sizeof(timeout_sys)))
2290                 datagrams = -EFAULT;
2291 
2292         return datagrams;
2293 }
2294 
2295 #ifdef __ARCH_WANT_SYS_SOCKETCALL
2296 /* Argument list sizes for sys_socketcall */
2297 #define AL(x) ((x) * sizeof(unsigned long))
2298 static const unsigned char nargs[21] = {
2299         AL(0), AL(3), AL(3), AL(3), AL(2), AL(3),
2300         AL(3), AL(3), AL(4), AL(4), AL(4), AL(6),
2301         AL(6), AL(2), AL(5), AL(5), AL(3), AL(3),
2302         AL(4), AL(5), AL(4)
2303 };
2304 
2305 #undef AL
2306 
2307 /*
2308  *      System call vectors.
2309  *
2310  *      Argument checking cleaned up. Saved 20% in size.
2311  *  This function doesn't need to set the kernel lock because
2312  *  it is set by the callees.
2313  */
2314 
2315 SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
2316 {
2317         unsigned long a[AUDITSC_ARGS];
2318         unsigned long a0, a1;
2319         int err;
2320         unsigned int len;
2321 
2322         if (call < 1 || call > SYS_SENDMMSG)
2323                 return -EINVAL;
2324 
2325         len = nargs[call];
2326         if (len > sizeof(a))
2327                 return -EINVAL;
2328 
2329         /* copy_from_user should be SMP safe. */
2330         if (copy_from_user(a, args, len))
2331                 return -EFAULT;
2332 
2333         err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
2334         if (err)
2335                 return err;
2336 
2337         a0 = a[0];
2338         a1 = a[1];
2339 
2340         switch (call) {
2341         case SYS_SOCKET:
2342                 err = sys_socket(a0, a1, a[2]);
2343                 break;
2344         case SYS_BIND:
2345                 err = sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
2346                 break;
2347         case SYS_CONNECT:
2348                 err = sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
2349                 break;
2350         case SYS_LISTEN:
2351                 err = sys_listen(a0, a1);
2352                 break;
2353         case SYS_ACCEPT:
2354                 err = sys_accept4(a0, (struct sockaddr __user *)a1,
2355                                   (int __user *)a[2], 0);
2356                 break;
2357         case SYS_GETSOCKNAME:
2358                 err =
2359                     sys_getsockname(a0, (struct sockaddr __user *)a1,
2360                                     (int __user *)a[2]);
2361                 break;
2362         case SYS_GETPEERNAME:
2363                 err =
2364                     sys_getpeername(a0, (struct sockaddr __user *)a1,
2365                                     (int __user *)a[2]);
2366                 break;
2367         case SYS_SOCKETPAIR:
2368                 err = sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
2369                 break;
2370         case SYS_SEND:
2371                 err = sys_send(a0, (void __user *)a1, a[2], a[3]);
2372                 break;
2373         case SYS_SENDTO:
2374                 err = sys_sendto(a0, (void __user *)a1, a[2], a[3],
2375                                  (struct sockaddr __user *)a[4], a[5]);
2376                 break;
2377         case SYS_RECV:
2378                 err = sys_recv(a0, (void __user *)a1, a[2], a[3]);
2379                 break;
2380         case SYS_RECVFROM:
2381                 err = sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
2382                                    (struct sockaddr __user *)a[4],
2383                                    (int __user *)a[5]);
2384                 break;
2385         case SYS_SHUTDOWN:
2386                 err = sys_shutdown(a0, a1);
2387                 break;
2388         case SYS_SETSOCKOPT:
2389                 err = sys_setsockopt(a0, a1, a[2], (char __user *)a[3], a[4]);
2390                 break;
2391         case SYS_GETSOCKOPT:
2392                 err =
2393                     sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
2394                                    (int __user *)a[4]);
2395                 break;
2396         case SYS_SENDMSG:
2397                 err = sys_sendmsg(a0, (struct user_msghdr __user *)a1, a[2]);
2398                 break;
2399         case SYS_SENDMMSG:
2400                 err = sys_sendmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3]);
2401                 break;
2402         case SYS_RECVMSG:
2403                 err = sys_recvmsg(a0, (struct user_msghdr __user *)a1, a[2]);
2404                 break;
2405         case SYS_RECVMMSG:
2406                 err = sys_recvmmsg(a0, (struct mmsghdr __user *)a1, a[2], a[3],
2407                                    (struct timespec __user *)a[4]);
2408                 break;
2409         case SYS_ACCEPT4:
2410                 err = sys_accept4(a0, (struct sockaddr __user *)a1,
2411                                   (int __user *)a[2], a[3]);
2412                 break;
2413         default:
2414                 err = -EINVAL;
2415                 break;
2416         }
2417         return err;
2418 }
2419 
2420 #endif                          /* __ARCH_WANT_SYS_SOCKETCALL */
2421 
2422 /**
2423  *      sock_register - add a socket protocol handler
2424  *      @ops: description of protocol
2425  *
2426  *      This function is called by a protocol handler that wants to
2427  *      advertise its address family, and have it linked into the
2428  *      socket interface. The value ops->family corresponds to the
2429  *      socket system call protocol family.
2430  */
2431 int sock_register(const struct net_proto_family *ops)
2432 {
2433         int err;
2434 
2435         if (ops->family >= NPROTO) {
2436                 pr_crit("protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
2437                 return -ENOBUFS;
2438         }
2439 
2440         spin_lock(&net_family_lock);
2441         if (rcu_dereference_protected(net_families[ops->family],
2442                                       lockdep_is_held(&net_family_lock)))
2443                 err = -EEXIST;
2444         else {
2445                 rcu_assign_pointer(net_families[ops->family], ops);
2446                 err = 0;
2447         }
2448         spin_unlock(&net_family_lock);
2449 
2450         pr_info("NET: Registered protocol family %d\n", ops->family);
2451         return err;
2452 }
2453 EXPORT_SYMBOL(sock_register);
2454 
2455 /**
2456  *      sock_unregister - remove a protocol handler
2457  *      @family: protocol family to remove
2458  *
2459  *      This function is called by a protocol handler that wants to
2460  *      remove its address family, and have it unlinked from the
2461  *      new socket creation.
2462  *
2463  *      If protocol handler is a module, then it can use module reference
2464  *      counts to protect against new references. If protocol handler is not
2465  *      a module then it needs to provide its own protection in
2466  *      the ops->create routine.
2467  */
2468 void sock_unregister(int family)
2469 {
2470         BUG_ON(family < 0 || family >= NPROTO);
2471 
2472         spin_lock(&net_family_lock);
2473         RCU_INIT_POINTER(net_families[family], NULL);
2474         spin_unlock(&net_family_lock);
2475 
2476         synchronize_rcu();
2477 
2478         pr_info("NET: Unregistered protocol family %d\n", family);
2479 }
2480 EXPORT_SYMBOL(sock_unregister);
2481 
2482 static int __init sock_init(void)
2483 {
2484         int err;
2485         /*
2486          *      Initialize the network sysctl infrastructure.
2487          */
2488         err = net_sysctl_init();
2489         if (err)
2490                 goto out;
2491 
2492         /*
2493          *      Initialize skbuff SLAB cache
2494          */
2495         skb_init();
2496 
2497         /*
2498          *      Initialize the protocols module.
2499          */
2500 
2501         init_inodecache();
2502 
2503         err = register_filesystem(&sock_fs_type);
2504         if (err)
2505                 goto out_fs;
2506         sock_mnt = kern_mount(&sock_fs_type);
2507         if (IS_ERR(sock_mnt)) {
2508                 err = PTR_ERR(sock_mnt);
2509                 goto out_mount;
2510         }
2511 
2512         /* The real protocol initialization is performed in later initcalls.
2513          */
2514 
2515 #ifdef CONFIG_NETFILTER
2516         err = netfilter_init();
2517         if (err)
2518                 goto out;
2519 #endif
2520 
2521         ptp_classifier_init();
2522 
2523 out:
2524         return err;
2525 
2526 out_mount:
2527         unregister_filesystem(&sock_fs_type);
2528 out_fs:
2529         goto out;
2530 }
2531 
2532 core_initcall(sock_init);       /* early initcall */
2533 
2534 #ifdef CONFIG_PROC_FS
2535 void socket_seq_show(struct seq_file *seq)
2536 {
2537         int cpu;
2538         int counter = 0;
2539 
2540         for_each_possible_cpu(cpu)
2541             counter += per_cpu(sockets_in_use, cpu);
2542 
2543         /* It can be negative, by the way. 8) */
2544         if (counter < 0)
2545                 counter = 0;
2546 
2547         seq_printf(seq, "sockets: used %d\n", counter);
2548 }
2549 #endif                          /* CONFIG_PROC_FS */
2550 
2551 #ifdef CONFIG_COMPAT
2552 static int do_siocgstamp(struct net *net, struct socket *sock,
2553                          unsigned int cmd, void __user *up)
2554 {
2555         mm_segment_t old_fs = get_fs();
2556         struct timeval ktv;
2557         int err;
2558 
2559         set_fs(KERNEL_DS);
2560         err = sock_do_ioctl(net, sock, cmd, (unsigned long)&ktv);
2561         set_fs(old_fs);
2562         if (!err)
2563                 err = compat_put_timeval(&ktv, up);
2564 
2565         return err;
2566 }
2567 
2568 static int do_siocgstampns(struct net *net, struct socket *sock,
2569                            unsigned int cmd, void __user *up)
2570 {
2571         mm_segment_t old_fs = get_fs();
2572         struct timespec kts;
2573         int err;
2574 
2575         set_fs(KERNEL_DS);
2576         err = sock_do_ioctl(net, sock, cmd, (unsigned long)&kts);
2577         set_fs(old_fs);
2578         if (!err)
2579                 err = compat_put_timespec(&kts, up);
2580 
2581         return err;
2582 }
2583 
2584 static int dev_ifname32(struct net *net, struct compat_ifreq __user *uifr32)
2585 {
2586         struct ifreq __user *uifr;
2587         int err;
2588 
2589         uifr = compat_alloc_user_space(sizeof(struct ifreq));
2590         if (copy_in_user(uifr, uifr32, sizeof(struct compat_ifreq)))
2591                 return -EFAULT;
2592 
2593         err = dev_ioctl(net, SIOCGIFNAME, uifr);
2594         if (err)
2595                 return err;
2596 
2597         if (copy_in_user(uifr32, uifr, sizeof(struct compat_ifreq)))
2598                 return -EFAULT;
2599 
2600         return 0;
2601 }
2602 
2603 static int dev_ifconf(struct net *net, struct compat_ifconf __user *uifc32)
2604 {
2605         struct compat_ifconf ifc32;
2606         struct ifconf ifc;
2607         struct ifconf __user *uifc;
2608         struct compat_ifreq __user *ifr32;
2609         struct ifreq __user *ifr;
2610         unsigned int i, j;
2611         int err;
2612 
2613         if (copy_from_user(&ifc32, uifc32, sizeof(struct compat_ifconf)))
2614                 return -EFAULT;
2615 
2616         memset(&ifc, 0, sizeof(ifc));
2617         if (ifc32.ifcbuf == 0) {
2618                 ifc32.ifc_len = 0;
2619                 ifc.ifc_len = 0;
2620                 ifc.ifc_req = NULL;
2621                 uifc = compat_alloc_user_space(sizeof(struct ifconf));
2622         } else {
2623                 size_t len = ((ifc32.ifc_len / sizeof(struct compat_ifreq)) + 1) *
2624                         sizeof(struct ifreq);
2625                 uifc = compat_alloc_user_space(sizeof(struct ifconf) + len);
2626                 ifc.ifc_len = len;
2627                 ifr = ifc.ifc_req = (void __user *)(uifc + 1);
2628                 ifr32 = compat_ptr(ifc32.ifcbuf);
2629                 for (i = 0; i < ifc32.ifc_len; i += sizeof(struct compat_ifreq)) {
2630                         if (copy_in_user(ifr, ifr32, sizeof(struct compat_ifreq)))
2631                                 return -EFAULT;
2632                         ifr++;
2633                         ifr32++;
2634                 }
2635         }
2636         if (copy_to_user(uifc, &ifc, sizeof(struct ifconf)))
2637                 return -EFAULT;
2638 
2639         err = dev_ioctl(net, SIOCGIFCONF, uifc);
2640         if (err)
2641                 return err;
2642 
2643         if (copy_from_user(&ifc, uifc, sizeof(struct ifconf)))
2644                 return -EFAULT;
2645 
2646         ifr = ifc.ifc_req;
2647         ifr32 = compat_ptr(ifc32.ifcbuf);
2648         for (i = 0, j = 0;
2649              i + sizeof(struct compat_ifreq) <= ifc32.ifc_len && j < ifc.ifc_len;
2650              i += sizeof(struct compat_ifreq), j += sizeof(struct ifreq)) {
2651                 if (copy_in_user(ifr32, ifr, sizeof(struct compat_ifreq)))
2652                         return -EFAULT;
2653                 ifr32++;
2654                 ifr++;
2655         }
2656 
2657         if (ifc32.ifcbuf == 0) {
2658                 /* Translate from 64-bit structure multiple to
2659                  * a 32-bit one.
2660                  */
2661                 i = ifc.ifc_len;
2662                 i = ((i / sizeof(struct ifreq)) * sizeof(struct compat_ifreq));
2663                 ifc32.ifc_len = i;
2664         } else {
2665                 ifc32.ifc_len = i;
2666         }
2667         if (copy_to_user(uifc32, &ifc32, sizeof(struct compat_ifconf)))
2668                 return -EFAULT;
2669 
2670         return 0;
2671 }
2672 
2673 static int ethtool_ioctl(struct net *net, struct compat_ifreq __user *ifr32)
2674 {
2675         struct compat_ethtool_rxnfc __user *compat_rxnfc;
2676         bool convert_in = false, convert_out = false;
2677         size_t buf_size = ALIGN(sizeof(struct ifreq), 8);
2678         struct ethtool_rxnfc __user *rxnfc;
2679         struct ifreq __user *ifr;
2680         u32 rule_cnt = 0, actual_rule_cnt;
2681         u32 ethcmd;
2682         u32 data;
2683         int ret;
2684 
2685         if (get_user(data, &ifr32->ifr_ifru.ifru_data))
2686                 return -EFAULT;
2687 
2688         compat_rxnfc = compat_ptr(data);
2689 
2690         if (get_user(ethcmd, &compat_rxnfc->cmd))
2691                 return -EFAULT;
2692 
2693         /* Most ethtool structures are defined without padding.
2694          * Unfortunately struct ethtool_rxnfc is an exception.
2695          */
2696         switch (ethcmd) {
2697         default:
2698                 break;
2699         case ETHTOOL_GRXCLSRLALL:
2700                 /* Buffer size is variable */
2701                 if (get_user(rule_cnt, &compat_rxnfc->rule_cnt))
2702                         return -EFAULT;
2703                 if (rule_cnt > KMALLOC_MAX_SIZE / sizeof(u32))
2704                         return -ENOMEM;
2705                 buf_size += rule_cnt * sizeof(u32);
2706                 /* fall through */
2707         case ETHTOOL_GRXRINGS:
2708         case ETHTOOL_GRXCLSRLCNT:
2709         case ETHTOOL_GRXCLSRULE:
2710         case ETHTOOL_SRXCLSRLINS:
2711                 convert_out = true;
2712                 /* fall through */
2713         case ETHTOOL_SRXCLSRLDEL:
2714                 buf_size += sizeof(struct ethtool_rxnfc);
2715                 convert_in = true;
2716                 break;
2717         }
2718 
2719         ifr = compat_alloc_user_space(buf_size);
2720         rxnfc = (void __user *)ifr + ALIGN(sizeof(struct ifreq), 8);
2721 
2722         if (copy_in_user(&ifr->ifr_name, &ifr32->ifr_name, IFNAMSIZ))
2723                 return -EFAULT;
2724 
2725         if (put_user(convert_in ? rxnfc : compat_ptr(data),
2726                      &ifr->ifr_ifru.ifru_data))
2727                 return -EFAULT;
2728 
2729         if (convert_in) {
2730                 /* We expect there to be holes between fs.m_ext and
2731                  * fs.ring_cookie and at the end of fs, but nowhere else.
2732                  */
2733                 BUILD_BUG_ON(offsetof(struct compat_ethtool_rxnfc, fs.m_ext) +
2734                              sizeof(compat_rxnfc->fs.m_ext) !=
2735                              offsetof(struct ethtool_rxnfc, fs.m_ext) +
2736                              sizeof(rxnfc->fs.m_ext));
2737                 BUILD_BUG_ON(
2738                         offsetof(struct compat_ethtool_rxnfc, fs.location) -
2739                         offsetof(struct compat_ethtool_rxnfc, fs.ring_cookie) !=
2740                         offsetof(struct ethtool_rxnfc, fs.location) -
2741                         offsetof(struct ethtool_rxnfc, fs.ring_cookie));
2742 
2743                 if (copy_in_user(rxnfc, compat_rxnfc,
2744                                  (void __user *)(&rxnfc->fs.m_ext + 1) -
2745                                  (void __user *)rxnfc) ||
2746                     copy_in_user(&rxnfc->fs.ring_cookie,
2747                                  &compat_rxnfc->fs.ring_cookie,
2748                                  (void __user *)(&rxnfc->fs.location + 1) -
2749                                  (void __user *)&rxnfc->fs.ring_cookie) ||
2750                     copy_in_user(&rxnfc->rule_cnt, &compat_rxnfc->rule_cnt,
2751                                  sizeof(rxnfc->rule_cnt)))
2752                         return -EFAULT;
2753         }
2754 
2755         ret = dev_ioctl(net, SIOCETHTOOL, ifr);
2756         if (ret)
2757                 return ret;
2758 
2759         if (convert_out) {
2760                 if (copy_in_user(compat_rxnfc, rxnfc,
2761                                  (const void __user *)(&rxnfc->fs.m_ext + 1) -
2762                                  (const void __user *)rxnfc) ||
2763                     copy_in_user(&compat_rxnfc->fs.ring_cookie,
2764                                  &rxnfc->fs.ring_cookie,
2765                                  (const void __user *)(&rxnfc->fs.location + 1) -
2766                                  (const void __user *)&rxnfc->fs.ring_cookie) ||
2767                     copy_in_user(&compat_rxnfc->rule_cnt, &rxnfc->rule_cnt,
2768                                  sizeof(rxnfc->rule_cnt)))
2769                         return -EFAULT;
2770 
2771                 if (ethcmd == ETHTOOL_GRXCLSRLALL) {
2772                         /* As an optimisation, we only copy the actual
2773                          * number of rules that the underlying
2774                          * function returned.  Since Mallory might
2775                          * change the rule count in user memory, we
2776                          * check that it is less than the rule count
2777                          * originally given (as the user buffer size),
2778                          * which has been range-checked.
2779                          */
2780                         if (get_user(actual_rule_cnt, &rxnfc->rule_cnt))
2781                                 return -EFAULT;
2782                         if (actual_rule_cnt < rule_cnt)
2783                                 rule_cnt = actual_rule_cnt;
2784                         if (copy_in_user(&compat_rxnfc->rule_locs[0],
2785                                          &rxnfc->rule_locs[0],
2786                                          rule_cnt * sizeof(u32)))
2787                                 return -EFAULT;
2788                 }
2789         }
2790 
2791         return 0;
2792 }
2793 
2794 static int compat_siocwandev(struct net *net, struct compat_ifreq __user *uifr32)
2795 {
2796         void __user *uptr;
2797         compat_uptr_t uptr32;
2798         struct ifreq __user *uifr;
2799 
2800         uifr = compat_alloc_user_space(sizeof(*uifr));
2801         if (copy_in_user(uifr, uifr32, sizeof(struct compat_ifreq)))
2802                 return -EFAULT;
2803 
2804         if (get_user(uptr32, &uifr32->ifr_settings.ifs_ifsu))
2805                 return -EFAULT;
2806 
2807         uptr = compat_ptr(uptr32);
2808 
2809         if (put_user(uptr, &uifr->ifr_settings.ifs_ifsu.raw_hdlc))
2810                 return -EFAULT;
2811 
2812         return dev_ioctl(net, SIOCWANDEV, uifr);
2813 }
2814 
2815 static int bond_ioctl(struct net *net, unsigned int cmd,
2816                          struct compat_ifreq __user *ifr32)
2817 {
2818         struct ifreq kifr;
2819         mm_segment_t old_fs;
2820         int err;
2821 
2822         switch (cmd) {
2823         case SIOCBONDENSLAVE:
2824         case SIOCBONDRELEASE:
2825         case SIOCBONDSETHWADDR:
2826         case SIOCBONDCHANGEACTIVE:
2827                 if (copy_from_user(&kifr, ifr32, sizeof(struct compat_ifreq)))
2828                         return -EFAULT;
2829 
2830                 old_fs = get_fs();
2831                 set_fs(KERNEL_DS);
2832                 err = dev_ioctl(net, cmd,
2833                                 (struct ifreq __user __force *) &kifr);
2834                 set_fs(old_fs);
2835 
2836                 return err;
2837         default:
2838                 return -ENOIOCTLCMD;
2839         }
2840 }
2841 
2842 /* Handle ioctls that use ifreq::ifr_data and just need struct ifreq converted */
2843 static int compat_ifr_data_ioctl(struct net *net, unsigned int cmd,
2844                                  struct compat_ifreq __user *u_ifreq32)
2845 {
2846         struct ifreq __user *u_ifreq64;
2847         char tmp_buf[IFNAMSIZ];
2848         void __user *data64;
2849         u32 data32;
2850 
2851         if (copy_from_user(&tmp_buf[0], &(u_ifreq32->ifr_ifrn.ifrn_name[0]),
2852                            IFNAMSIZ))
2853                 return -EFAULT;
2854         if (get_user(data32, &u_ifreq32->ifr_ifru.ifru_data))
2855                 return -EFAULT;
2856         data64 = compat_ptr(data32);
2857 
2858         u_ifreq64 = compat_alloc_user_space(sizeof(*u_ifreq64));
2859 
2860         if (copy_to_user(&u_ifreq64->ifr_ifrn.ifrn_name[0], &tmp_buf[0],
2861                          IFNAMSIZ))
2862                 return -EFAULT;
2863         if (put_user(data64, &u_ifreq64->ifr_ifru.ifru_data))
2864                 return -EFAULT;
2865 
2866         return dev_ioctl(net, cmd, u_ifreq64);
2867 }
2868 
2869 static int dev_ifsioc(struct net *net, struct socket *sock,
2870                          unsigned int cmd, struct compat_ifreq __user *uifr32)
2871 {
2872         struct ifreq __user *uifr;
2873         int err;
2874 
2875         uifr = compat_alloc_user_space(sizeof(*uifr));
2876         if (copy_in_user(uifr, uifr32, sizeof(*uifr32)))
2877                 return -EFAULT;
2878 
2879         err = sock_do_ioctl(net, sock, cmd, (unsigned long)uifr);
2880 
2881         if (!err) {
2882                 switch (cmd) {
2883                 case SIOCGIFFLAGS:
2884                 case SIOCGIFMETRIC:
2885                 case SIOCGIFMTU:
2886                 case SIOCGIFMEM:
2887                 case SIOCGIFHWADDR:
2888                 case SIOCGIFINDEX:
2889                 case SIOCGIFADDR:
2890                 case SIOCGIFBRDADDR:
2891                 case SIOCGIFDSTADDR:
2892                 case SIOCGIFNETMASK:
2893                 case SIOCGIFPFLAGS:
2894                 case SIOCGIFTXQLEN:
2895                 case SIOCGMIIPHY:
2896                 case SIOCGMIIREG:
2897                         if (copy_in_user(uifr32, uifr, sizeof(*uifr32)))
2898                                 err = -EFAULT;
2899                         break;
2900                 }
2901         }
2902         return err;
2903 }
2904 
2905 static int compat_sioc_ifmap(struct net *net, unsigned int cmd,
2906                         struct compat_ifreq __user *uifr32)
2907 {
2908         struct ifreq ifr;
2909         struct compat_ifmap __user *uifmap32;
2910         mm_segment_t old_fs;
2911         int err;
2912 
2913         uifmap32 = &uifr32->ifr_ifru.ifru_map;
2914         err = copy_from_user(&ifr, uifr32, sizeof(ifr.ifr_name));
2915         err |= get_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
2916         err |= get_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
2917         err |= get_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
2918         err |= get_user(ifr.ifr_map.irq, &uifmap32->irq);
2919         err |= get_user(ifr.ifr_map.dma, &uifmap32->dma);
2920         err |= get_user(ifr.ifr_map.port, &uifmap32->port);
2921         if (err)
2922                 return -EFAULT;
2923 
2924         old_fs = get_fs();
2925         set_fs(KERNEL_DS);
2926         err = dev_ioctl(net, cmd, (void  __user __force *)&ifr);
2927         set_fs(old_fs);
2928 
2929         if (cmd == SIOCGIFMAP && !err) {
2930                 err = copy_to_user(uifr32, &ifr, sizeof(ifr.ifr_name));
2931                 err |= put_user(ifr.ifr_map.mem_start, &uifmap32->mem_start);
2932                 err |= put_user(ifr.ifr_map.mem_end, &uifmap32->mem_end);
2933                 err |= put_user(ifr.ifr_map.base_addr, &uifmap32->base_addr);
2934                 err |= put_user(ifr.ifr_map.irq, &uifmap32->irq);
2935                 err |= put_user(ifr.ifr_map.dma, &uifmap32->dma);
2936                 err |= put_user(ifr.ifr_map.port, &uifmap32->port);
2937                 if (err)
2938                         err = -EFAULT;
2939         }
2940         return err;
2941 }
2942 
2943 struct rtentry32 {
2944         u32             rt_pad1;
2945         struct sockaddr rt_dst;         /* target address               */
2946         struct sockaddr rt_gateway;     /* gateway addr (RTF_GATEWAY)   */
2947         struct sockaddr rt_genmask;     /* target network mask (IP)     */
2948         unsigned short  rt_flags;
2949         short           rt_pad2;
2950         u32             rt_pad3;
2951         unsigned char   rt_tos;
2952         unsigned char   rt_class;
2953         short           rt_pad4;
2954         short           rt_metric;      /* +1 for binary compatibility! */
2955         /* char * */ u32 rt_dev;        /* forcing the device at add    */
2956         u32             rt_mtu;         /* per route MTU/Window         */
2957         u32             rt_window;      /* Window clamping              */
2958         unsigned short  rt_irtt;        /* Initial RTT                  */
2959 };
2960 
2961 struct in6_rtmsg32 {
2962         struct in6_addr         rtmsg_dst;
2963         struct in6_addr         rtmsg_src;
2964         struct in6_addr         rtmsg_gateway;
2965         u32                     rtmsg_type;
2966         u16                     rtmsg_dst_len;
2967         u16                     rtmsg_src_len;
2968         u32                     rtmsg_metric;
2969         u32                     rtmsg_info;
2970         u32                     rtmsg_flags;
2971         s32                     rtmsg_ifindex;
2972 };
2973 
2974 static int routing_ioctl(struct net *net, struct socket *sock,
2975                          unsigned int cmd, void __user *argp)
2976 {
2977         int ret;
2978         void *r = NULL;
2979         struct in6_rtmsg r6;
2980         struct rtentry r4;
2981         char devname[16];
2982         u32 rtdev;
2983         mm_segment_t old_fs = get_fs();
2984 
2985         if (sock && sock->sk && sock->sk->sk_family == AF_INET6) { /* ipv6 */
2986                 struct in6_rtmsg32 __user *ur6 = argp;
2987                 ret = copy_from_user(&r6.rtmsg_dst, &(ur6->rtmsg_dst),
2988                         3 * sizeof(struct in6_addr));
2989                 ret |= get_user(r6.rtmsg_type, &(ur6->rtmsg_type));
2990                 ret |= get_user(r6.rtmsg_dst_len, &(ur6->rtmsg_dst_len));
2991                 ret |= get_user(r6.rtmsg_src_len, &(ur6->rtmsg_src_len));
2992                 ret |= get_user(r6.rtmsg_metric, &(ur6->rtmsg_metric));
2993                 ret |= get_user(r6.rtmsg_info, &(ur6->rtmsg_info));
2994                 ret |= get_user(r6.rtmsg_flags, &(ur6->rtmsg_flags));
2995                 ret |= get_user(r6.rtmsg_ifindex, &(ur6->rtmsg_ifindex));
2996 
2997                 r = (void *) &r6;
2998         } else { /* ipv4 */
2999                 struct rtentry32 __user *ur4 = argp;
3000                 ret = copy_from_user(&r4.rt_dst, &(ur4->rt_dst),
3001                                         3 * sizeof(struct sockaddr));
3002                 ret |= get_user(r4.rt_flags, &(ur4->rt_flags));
3003                 ret |= get_user(r4.rt_metric, &(ur4->rt_metric));
3004                 ret |= get_user(r4.rt_mtu, &(ur4->rt_mtu));
3005                 ret |= get_user(r4.rt_window, &(ur4->rt_window));
3006                 ret |= get_user(r4.rt_irtt, &(ur4->rt_irtt));
3007                 ret |= get_user(rtdev, &(ur4->rt_dev));
3008                 if (rtdev) {
3009                         ret |= copy_from_user(devname, compat_ptr(rtdev), 15);
3010                         r4.rt_dev = (char __user __force *)devname;
3011                         devname[15] = 0;
3012                 } else
3013                         r4.rt_dev = NULL;
3014 
3015                 r = (void *) &r4;
3016         }
3017 
3018         if (ret) {
3019                 ret = -EFAULT;
3020                 goto out;
3021         }
3022 
3023         set_fs(KERNEL_DS);
3024         ret = sock_do_ioctl(net, sock, cmd, (unsigned long) r);
3025         set_fs(old_fs);
3026 
3027 out:
3028         return ret;
3029 }
3030 
3031 /* Since old style bridge ioctl's endup using SIOCDEVPRIVATE
3032  * for some operations; this forces use of the newer bridge-utils that
3033  * use compatible ioctls
3034  */
3035 static int old_bridge_ioctl(compat_ulong_t __user *argp)
3036 {
3037         compat_ulong_t tmp;
3038 
3039         if (get_user(tmp, argp))
3040                 return -EFAULT;
3041         if (tmp == BRCTL_GET_VERSION)
3042                 return BRCTL_VERSION + 1;
3043         return -EINVAL;
3044 }
3045 
3046 static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
3047                          unsigned int cmd, unsigned long arg)
3048 {
3049         void __user *argp = compat_ptr(arg);
3050         struct sock *sk = sock->sk;
3051         struct net *net = sock_net(sk);
3052 
3053         if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15))
3054                 return compat_ifr_data_ioctl(net, cmd, argp);
3055 
3056         switch (cmd) {
3057         case SIOCSIFBR:
3058         case SIOCGIFBR:
3059                 return old_bridge_ioctl(argp);
3060         case SIOCGIFNAME:
3061                 return dev_ifname32(net, argp);
3062         case SIOCGIFCONF:
3063                 return dev_ifconf(net, argp);
3064         case SIOCETHTOOL:
3065                 return ethtool_ioctl(net, argp);
3066         case SIOCWANDEV:
3067                 return compat_siocwandev(net, argp);
3068         case SIOCGIFMAP:
3069         case SIOCSIFMAP:
3070                 return compat_sioc_ifmap(net, cmd, argp);
3071         case SIOCBONDENSLAVE:
3072         case SIOCBONDRELEASE:
3073         case SIOCBONDSETHWADDR:
3074         case SIOCBONDCHANGEACTIVE:
3075                 return bond_ioctl(net, cmd, argp);
3076         case SIOCADDRT:
3077         case SIOCDELRT:
3078                 return routing_ioctl(net, sock, cmd, argp);
3079         case SIOCGSTAMP:
3080                 return do_siocgstamp(net, sock, cmd, argp);
3081         case SIOCGSTAMPNS:
3082                 return do_siocgstampns(net, sock, cmd, argp);
3083         case SIOCBONDSLAVEINFOQUERY:
3084         case SIOCBONDINFOQUERY:
3085         case SIOCSHWTSTAMP:
3086         case SIOCGHWTSTAMP:
3087                 return compat_ifr_data_ioctl(net, cmd, argp);
3088 
3089         case FIOSETOWN:
3090         case SIOCSPGRP:
3091         case FIOGETOWN:
3092         case SIOCGPGRP:
3093         case SIOCBRADDBR:
3094         case SIOCBRDELBR:
3095         case SIOCGIFVLAN:
3096         case SIOCSIFVLAN:
3097         case SIOCADDDLCI:
3098         case SIOCDELDLCI:
3099                 return sock_ioctl(file, cmd, arg);
3100 
3101         case SIOCGIFFLAGS:
3102         case SIOCSIFFLAGS:
3103         case SIOCGIFMETRIC:
3104         case SIOCSIFMETRIC:
3105         case SIOCGIFMTU:
3106         case SIOCSIFMTU:
3107         case SIOCGIFMEM:
3108         case SIOCSIFMEM:
3109         case SIOCGIFHWADDR:
3110         case SIOCSIFHWADDR:
3111         case SIOCADDMULTI:
3112         case SIOCDELMULTI:
3113         case SIOCGIFINDEX:
3114         case SIOCGIFADDR:
3115         case SIOCSIFADDR:
3116         case SIOCSIFHWBROADCAST:
3117         case SIOCDIFADDR:
3118         case SIOCGIFBRDADDR:
3119         case SIOCSIFBRDADDR:
3120         case SIOCGIFDSTADDR:
3121         case SIOCSIFDSTADDR:
3122         case SIOCGIFNETMASK:
3123         case SIOCSIFNETMASK:
3124         case SIOCSIFPFLAGS:
3125         case SIOCGIFPFLAGS:
3126         case SIOCGIFTXQLEN:
3127         case SIOCSIFTXQLEN:
3128         case SIOCBRADDIF:
3129         case SIOCBRDELIF:
3130         case SIOCSIFNAME:
3131         case SIOCGMIIPHY:
3132         case SIOCGMIIREG:
3133         case SIOCSMIIREG:
3134                 return dev_ifsioc(net, sock, cmd, argp);
3135 
3136         case SIOCSARP:
3137         case SIOCGARP:
3138         case SIOCDARP:
3139         case SIOCATMARK:
3140                 return sock_do_ioctl(net, sock, cmd, arg);
3141         }
3142 
3143         return -ENOIOCTLCMD;
3144 }
3145 
3146 static long compat_sock_ioctl(struct file *file, unsigned int cmd,
3147                               unsigned long arg)
3148 {
3149         struct socket *sock = file->private_data;
3150         int ret = -ENOIOCTLCMD;
3151         struct sock *sk;
3152         struct net *net;
3153 
3154         sk = sock->sk;
3155         net = sock_net(sk);
3156 
3157         if (sock->ops->compat_ioctl)
3158                 ret = sock->ops->compat_ioctl(sock, cmd, arg);
3159 
3160         if (ret == -ENOIOCTLCMD &&
3161             (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
3162                 ret = compat_wext_handle_ioctl(net, cmd, arg);
3163 
3164         if (ret == -ENOIOCTLCMD)
3165                 ret = compat_sock_ioctl_trans(file, sock, cmd, arg);
3166 
3167         return ret;
3168 }
3169 #endif
3170 
3171 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
3172 {
3173         return sock->ops->bind(sock, addr, addrlen);
3174 }
3175 EXPORT_SYMBOL(kernel_bind);
3176 
3177 int kernel_listen(struct socket *sock, int backlog)
3178 {
3179         return sock->ops->listen(sock, backlog);
3180 }
3181 EXPORT_SYMBOL(kernel_listen);
3182 
3183 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
3184 {
3185         struct sock *sk = sock->sk;
3186         int err;
3187 
3188         err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
3189                                newsock);
3190         if (err < 0)
3191                 goto done;
3192 
3193         err = sock->ops->accept(sock, *newsock, flags);
3194         if (err < 0) {
3195                 sock_release(*newsock);
3196                 *newsock = NULL;
3197                 goto done;
3198         }
3199 
3200         (*newsock)->ops = sock->ops;
3201         __module_get((*newsock)->ops->owner);
3202 
3203 done:
3204         return err;
3205 }
3206 EXPORT_SYMBOL(kernel_accept);
3207 
3208 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
3209                    int flags)
3210 {
3211         return sock->ops->connect(sock, addr, addrlen, flags);
3212 }
3213 EXPORT_SYMBOL(kernel_connect);
3214 
3215 int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
3216                          int *addrlen)
3217 {
3218         return sock->ops->getname(sock, addr, addrlen, 0);
3219 }
3220 EXPORT_SYMBOL(kernel_getsockname);
3221 
3222 int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
3223                          int *addrlen)
3224 {
3225         return sock->ops->getname(sock, addr, addrlen, 1);
3226 }
3227 EXPORT_SYMBOL(kernel_getpeername);
3228 
3229 int kernel_getsockopt(struct socket *sock, int level, int optname,
3230                         char *optval, int *optlen)
3231 {
3232         mm_segment_t oldfs = get_fs();
3233         char __user *uoptval;
3234         int __user *uoptlen;
3235         int err;
3236 
3237         uoptval = (char __user __force *) optval;
3238         uoptlen = (int __user __force *) optlen;
3239 
3240         set_fs(KERNEL_DS);
3241         if (level == SOL_SOCKET)
3242                 err = sock_getsockopt(sock, level, optname, uoptval, uoptlen);
3243         else
3244                 err = sock->ops->getsockopt(sock, level, optname, uoptval,
3245                                             uoptlen);
3246         set_fs(oldfs);
3247         return err;
3248 }
3249 EXPORT_SYMBOL(kernel_getsockopt);
3250 
3251 int kernel_setsockopt(struct socket *sock, int level, int optname,
3252                         char *optval, unsigned int optlen)
3253 {
3254         mm_segment_t oldfs = get_fs();
3255         char __user *uoptval;
3256         int err;
3257 
3258         uoptval = (char __user __force *) optval;
3259 
3260         set_fs(KERNEL_DS);
3261         if (level == SOL_SOCKET)
3262                 err = sock_setsockopt(sock, level, optname, uoptval, optlen);
3263         else
3264                 err = sock->ops->setsockopt(sock, level, optname, uoptval,
3265                                             optlen);
3266         set_fs(oldfs);
3267         return err;
3268 }
3269 EXPORT_SYMBOL(kernel_setsockopt);
3270 
3271 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
3272                     size_t size, int flags)
3273 {
3274         if (sock->ops->sendpage)
3275                 return sock->ops->sendpage(sock, page, offset, size, flags);
3276 
3277         return sock_no_sendpage(sock, page, offset, size, flags);
3278 }
3279 EXPORT_SYMBOL(kernel_sendpage);
3280 
3281 int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg)
3282 {
3283         mm_segment_t oldfs = get_fs();
3284         int err;
3285 
3286         set_fs(KERNEL_DS);
3287         err = sock->ops->ioctl(sock, cmd, arg);
3288         set_fs(oldfs);
3289 
3290         return err;
3291 }
3292 EXPORT_SYMBOL(kernel_sock_ioctl);
3293 
3294 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
3295 {
3296         return sock->ops->shutdown(sock, how);
3297 }
3298 EXPORT_SYMBOL(kernel_sock_shutdown);
3299 

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