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