1 /* 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * From: @(#)uipc_usrreq.c 8.3 (Berkeley) 1/4/94 34 * $FreeBSD: src/sys/kern/uipc_usrreq.c,v 1.54.2.10 2003/03/04 17:28:09 nectar Exp $ 35 * $DragonFly: src/sys/kern/uipc_usrreq.c,v 1.39 2008/05/09 17:52:17 dillon Exp $ 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/domain.h> 42 #include <sys/fcntl.h> 43 #include <sys/malloc.h> /* XXX must be before <sys/file.h> */ 44 #include <sys/proc.h> 45 #include <sys/file.h> 46 #include <sys/filedesc.h> 47 #include <sys/mbuf.h> 48 #include <sys/nlookup.h> 49 #include <sys/protosw.h> 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> 52 #include <sys/resourcevar.h> 53 #include <sys/stat.h> 54 #include <sys/mount.h> 55 #include <sys/sysctl.h> 56 #include <sys/un.h> 57 #include <sys/unpcb.h> 58 #include <sys/vnode.h> 59 #include <sys/file2.h> 60 #include <sys/spinlock2.h> 61 62 #include <vm/vm_zone.h> 63 64 static struct vm_zone *unp_zone; 65 static unp_gen_t unp_gencnt; 66 static u_int unp_count; 67 68 static struct unp_head unp_shead, unp_dhead; 69 70 /* 71 * Unix communications domain. 72 * 73 * TODO: 74 * SEQPACKET, RDM 75 * rethink name space problems 76 * need a proper out-of-band 77 * lock pushdown 78 */ 79 static struct sockaddr sun_noname = { sizeof(sun_noname), AF_LOCAL }; 80 static ino_t unp_ino; /* prototype for fake inode numbers */ 81 82 static int unp_attach (struct socket *, struct pru_attach_info *); 83 static void unp_detach (struct unpcb *); 84 static int unp_bind (struct unpcb *,struct sockaddr *, struct thread *); 85 static int unp_connect (struct socket *,struct sockaddr *, 86 struct thread *); 87 static void unp_disconnect (struct unpcb *); 88 static void unp_shutdown (struct unpcb *); 89 static void unp_drop (struct unpcb *, int); 90 static void unp_gc (void); 91 static int unp_gc_clearmarks(struct file *, void *); 92 static int unp_gc_checkmarks(struct file *, void *); 93 static int unp_gc_checkrefs(struct file *, void *); 94 static void unp_scan (struct mbuf *, void (*)(struct file *, void *), 95 void *data); 96 static void unp_mark (struct file *, void *data); 97 static void unp_discard (struct file *, void *); 98 static int unp_internalize (struct mbuf *, struct thread *); 99 static int unp_listen (struct unpcb *, struct thread *); 100 101 static int 102 uipc_abort(struct socket *so) 103 { 104 struct unpcb *unp = so->so_pcb; 105 106 if (unp == NULL) 107 return EINVAL; 108 unp_drop(unp, ECONNABORTED); 109 unp_detach(unp); 110 sofree(so); 111 return 0; 112 } 113 114 static int 115 uipc_accept(struct socket *so, struct sockaddr **nam) 116 { 117 struct unpcb *unp = so->so_pcb; 118 119 if (unp == NULL) 120 return EINVAL; 121 122 /* 123 * Pass back name of connected socket, 124 * if it was bound and we are still connected 125 * (our peer may have closed already!). 126 */ 127 if (unp->unp_conn && unp->unp_conn->unp_addr) { 128 *nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr); 129 } else { 130 *nam = dup_sockaddr((struct sockaddr *)&sun_noname); 131 } 132 return 0; 133 } 134 135 static int 136 uipc_attach(struct socket *so, int proto, struct pru_attach_info *ai) 137 { 138 struct unpcb *unp = so->so_pcb; 139 140 if (unp != NULL) 141 return EISCONN; 142 return unp_attach(so, ai); 143 } 144 145 static int 146 uipc_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 147 { 148 struct unpcb *unp = so->so_pcb; 149 150 if (unp == NULL) 151 return EINVAL; 152 return unp_bind(unp, nam, td); 153 } 154 155 static int 156 uipc_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 157 { 158 struct unpcb *unp = so->so_pcb; 159 160 if (unp == NULL) 161 return EINVAL; 162 return unp_connect(so, nam, td); 163 } 164 165 static int 166 uipc_connect2(struct socket *so1, struct socket *so2) 167 { 168 struct unpcb *unp = so1->so_pcb; 169 170 if (unp == NULL) 171 return EINVAL; 172 173 return unp_connect2(so1, so2); 174 } 175 176 /* control is EOPNOTSUPP */ 177 178 static int 179 uipc_detach(struct socket *so) 180 { 181 struct unpcb *unp = so->so_pcb; 182 183 if (unp == NULL) 184 return EINVAL; 185 186 unp_detach(unp); 187 return 0; 188 } 189 190 static int 191 uipc_disconnect(struct socket *so) 192 { 193 struct unpcb *unp = so->so_pcb; 194 195 if (unp == NULL) 196 return EINVAL; 197 unp_disconnect(unp); 198 return 0; 199 } 200 201 static int 202 uipc_listen(struct socket *so, struct thread *td) 203 { 204 struct unpcb *unp = so->so_pcb; 205 206 if (unp == NULL || unp->unp_vnode == NULL) 207 return EINVAL; 208 return unp_listen(unp, td); 209 } 210 211 static int 212 uipc_peeraddr(struct socket *so, struct sockaddr **nam) 213 { 214 struct unpcb *unp = so->so_pcb; 215 216 if (unp == NULL) 217 return EINVAL; 218 if (unp->unp_conn && unp->unp_conn->unp_addr) 219 *nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr); 220 else { 221 /* 222 * XXX: It seems that this test always fails even when 223 * connection is established. So, this else clause is 224 * added as workaround to return PF_LOCAL sockaddr. 225 */ 226 *nam = dup_sockaddr((struct sockaddr *)&sun_noname); 227 } 228 return 0; 229 } 230 231 static int 232 uipc_rcvd(struct socket *so, int flags) 233 { 234 struct unpcb *unp = so->so_pcb; 235 struct socket *so2; 236 u_long newhiwat; 237 238 if (unp == NULL) 239 return EINVAL; 240 switch (so->so_type) { 241 case SOCK_DGRAM: 242 panic("uipc_rcvd DGRAM?"); 243 /*NOTREACHED*/ 244 245 case SOCK_STREAM: 246 if (unp->unp_conn == NULL) 247 break; 248 so2 = unp->unp_conn->unp_socket; 249 /* 250 * Adjust backpressure on sender 251 * and wakeup any waiting to write. 252 */ 253 so2->so_snd.ssb_mbmax += unp->unp_mbcnt - so->so_rcv.ssb_mbcnt; 254 unp->unp_mbcnt = so->so_rcv.ssb_mbcnt; 255 newhiwat = 256 so2->so_snd.ssb_hiwat + unp->unp_cc - so->so_rcv.ssb_cc; 257 chgsbsize(so2->so_cred->cr_uidinfo, &so2->so_snd.ssb_hiwat, 258 newhiwat, RLIM_INFINITY); 259 unp->unp_cc = so->so_rcv.ssb_cc; 260 sowwakeup(so2); 261 break; 262 263 default: 264 panic("uipc_rcvd unknown socktype"); 265 } 266 return 0; 267 } 268 269 /* pru_rcvoob is EOPNOTSUPP */ 270 271 static int 272 uipc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 273 struct mbuf *control, struct thread *td) 274 { 275 int error = 0; 276 struct unpcb *unp = so->so_pcb; 277 struct socket *so2; 278 u_long newhiwat; 279 280 if (unp == NULL) { 281 error = EINVAL; 282 goto release; 283 } 284 if (flags & PRUS_OOB) { 285 error = EOPNOTSUPP; 286 goto release; 287 } 288 289 if (control && (error = unp_internalize(control, td))) 290 goto release; 291 292 switch (so->so_type) { 293 case SOCK_DGRAM: 294 { 295 struct sockaddr *from; 296 297 if (nam) { 298 if (unp->unp_conn) { 299 error = EISCONN; 300 break; 301 } 302 error = unp_connect(so, nam, td); 303 if (error) 304 break; 305 } else { 306 if (unp->unp_conn == NULL) { 307 error = ENOTCONN; 308 break; 309 } 310 } 311 so2 = unp->unp_conn->unp_socket; 312 if (unp->unp_addr) 313 from = (struct sockaddr *)unp->unp_addr; 314 else 315 from = &sun_noname; 316 if (ssb_appendaddr(&so2->so_rcv, from, m, control)) { 317 sorwakeup(so2); 318 m = NULL; 319 control = NULL; 320 } else { 321 error = ENOBUFS; 322 } 323 if (nam) 324 unp_disconnect(unp); 325 break; 326 } 327 328 case SOCK_STREAM: 329 /* Connect if not connected yet. */ 330 /* 331 * Note: A better implementation would complain 332 * if not equal to the peer's address. 333 */ 334 if (!(so->so_state & SS_ISCONNECTED)) { 335 if (nam) { 336 error = unp_connect(so, nam, td); 337 if (error) 338 break; /* XXX */ 339 } else { 340 error = ENOTCONN; 341 break; 342 } 343 } 344 345 if (so->so_state & SS_CANTSENDMORE) { 346 error = EPIPE; 347 break; 348 } 349 if (unp->unp_conn == NULL) 350 panic("uipc_send connected but no connection?"); 351 so2 = unp->unp_conn->unp_socket; 352 /* 353 * Send to paired receive port, and then reduce 354 * send buffer hiwater marks to maintain backpressure. 355 * Wake up readers. 356 */ 357 if (control) { 358 if (ssb_appendcontrol(&so2->so_rcv, m, control)) { 359 control = NULL; 360 m = NULL; 361 } 362 } else { 363 sbappend(&so2->so_rcv.sb, m); 364 m = NULL; 365 } 366 so->so_snd.ssb_mbmax -= 367 so2->so_rcv.ssb_mbcnt - unp->unp_conn->unp_mbcnt; 368 unp->unp_conn->unp_mbcnt = so2->so_rcv.ssb_mbcnt; 369 newhiwat = so->so_snd.ssb_hiwat - 370 (so2->so_rcv.ssb_cc - unp->unp_conn->unp_cc); 371 chgsbsize(so->so_cred->cr_uidinfo, &so->so_snd.ssb_hiwat, 372 newhiwat, RLIM_INFINITY); 373 unp->unp_conn->unp_cc = so2->so_rcv.ssb_cc; 374 sorwakeup(so2); 375 break; 376 377 default: 378 panic("uipc_send unknown socktype"); 379 } 380 381 /* 382 * SEND_EOF is equivalent to a SEND followed by a SHUTDOWN. 383 */ 384 if (flags & PRUS_EOF) { 385 socantsendmore(so); 386 unp_shutdown(unp); 387 } 388 389 if (control && error != 0) 390 unp_dispose(control); 391 392 release: 393 if (control) 394 m_freem(control); 395 if (m) 396 m_freem(m); 397 return error; 398 } 399 400 static int 401 uipc_sense(struct socket *so, struct stat *sb) 402 { 403 struct unpcb *unp = so->so_pcb; 404 struct socket *so2; 405 406 if (unp == NULL) 407 return EINVAL; 408 sb->st_blksize = so->so_snd.ssb_hiwat; 409 if (so->so_type == SOCK_STREAM && unp->unp_conn != NULL) { 410 so2 = unp->unp_conn->unp_socket; 411 sb->st_blksize += so2->so_rcv.ssb_cc; 412 } 413 sb->st_dev = NOUDEV; 414 if (unp->unp_ino == 0) /* make up a non-zero inode number */ 415 unp->unp_ino = (++unp_ino == 0) ? ++unp_ino : unp_ino; 416 sb->st_ino = unp->unp_ino; 417 return (0); 418 } 419 420 static int 421 uipc_shutdown(struct socket *so) 422 { 423 struct unpcb *unp = so->so_pcb; 424 425 if (unp == NULL) 426 return EINVAL; 427 socantsendmore(so); 428 unp_shutdown(unp); 429 return 0; 430 } 431 432 static int 433 uipc_sockaddr(struct socket *so, struct sockaddr **nam) 434 { 435 struct unpcb *unp = so->so_pcb; 436 437 if (unp == NULL) 438 return EINVAL; 439 if (unp->unp_addr) 440 *nam = dup_sockaddr((struct sockaddr *)unp->unp_addr); 441 return 0; 442 } 443 444 struct pr_usrreqs uipc_usrreqs = { 445 .pru_abort = uipc_abort, 446 .pru_accept = uipc_accept, 447 .pru_attach = uipc_attach, 448 .pru_bind = uipc_bind, 449 .pru_connect = uipc_connect, 450 .pru_connect2 = uipc_connect2, 451 .pru_control = pru_control_notsupp, 452 .pru_detach = uipc_detach, 453 .pru_disconnect = uipc_disconnect, 454 .pru_listen = uipc_listen, 455 .pru_peeraddr = uipc_peeraddr, 456 .pru_rcvd = uipc_rcvd, 457 .pru_rcvoob = pru_rcvoob_notsupp, 458 .pru_send = uipc_send, 459 .pru_sense = uipc_sense, 460 .pru_shutdown = uipc_shutdown, 461 .pru_sockaddr = uipc_sockaddr, 462 .pru_sosend = sosend, 463 .pru_soreceive = soreceive, 464 .pru_sopoll = sopoll 465 }; 466 467 int 468 uipc_ctloutput(struct socket *so, struct sockopt *sopt) 469 { 470 struct unpcb *unp = so->so_pcb; 471 int error; 472 473 switch (sopt->sopt_dir) { 474 case SOPT_GET: 475 switch (sopt->sopt_name) { 476 case LOCAL_PEERCRED: 477 if (unp->unp_flags & UNP_HAVEPC) 478 error = sooptcopyout(sopt, &unp->unp_peercred, 479 sizeof(unp->unp_peercred)); 480 else { 481 if (so->so_type == SOCK_STREAM) 482 error = ENOTCONN; 483 else 484 error = EINVAL; 485 } 486 break; 487 default: 488 error = EOPNOTSUPP; 489 break; 490 } 491 break; 492 case SOPT_SET: 493 default: 494 error = EOPNOTSUPP; 495 break; 496 } 497 return (error); 498 } 499 500 /* 501 * Both send and receive buffers are allocated PIPSIZ bytes of buffering 502 * for stream sockets, although the total for sender and receiver is 503 * actually only PIPSIZ. 504 * Datagram sockets really use the sendspace as the maximum datagram size, 505 * and don't really want to reserve the sendspace. Their recvspace should 506 * be large enough for at least one max-size datagram plus address. 507 */ 508 #ifndef PIPSIZ 509 #define PIPSIZ 8192 510 #endif 511 static u_long unpst_sendspace = PIPSIZ; 512 static u_long unpst_recvspace = PIPSIZ; 513 static u_long unpdg_sendspace = 2*1024; /* really max datagram size */ 514 static u_long unpdg_recvspace = 4*1024; 515 516 static int unp_rights; /* file descriptors in flight */ 517 static struct spinlock unp_spin = SPINLOCK_INITIALIZER(&unp_spin); 518 519 SYSCTL_DECL(_net_local_stream); 520 SYSCTL_INT(_net_local_stream, OID_AUTO, sendspace, CTLFLAG_RW, 521 &unpst_sendspace, 0, ""); 522 SYSCTL_INT(_net_local_stream, OID_AUTO, recvspace, CTLFLAG_RW, 523 &unpst_recvspace, 0, ""); 524 525 SYSCTL_DECL(_net_local_dgram); 526 SYSCTL_INT(_net_local_dgram, OID_AUTO, maxdgram, CTLFLAG_RW, 527 &unpdg_sendspace, 0, ""); 528 SYSCTL_INT(_net_local_dgram, OID_AUTO, recvspace, CTLFLAG_RW, 529 &unpdg_recvspace, 0, ""); 530 531 SYSCTL_DECL(_net_local); 532 SYSCTL_INT(_net_local, OID_AUTO, inflight, CTLFLAG_RD, &unp_rights, 0, ""); 533 534 static int 535 unp_attach(struct socket *so, struct pru_attach_info *ai) 536 { 537 struct unpcb *unp; 538 int error; 539 540 if (so->so_snd.ssb_hiwat == 0 || so->so_rcv.ssb_hiwat == 0) { 541 switch (so->so_type) { 542 543 case SOCK_STREAM: 544 error = soreserve(so, unpst_sendspace, unpst_recvspace, 545 ai->sb_rlimit); 546 break; 547 548 case SOCK_DGRAM: 549 error = soreserve(so, unpdg_sendspace, unpdg_recvspace, 550 ai->sb_rlimit); 551 break; 552 553 default: 554 panic("unp_attach"); 555 } 556 if (error) 557 return (error); 558 } 559 unp = zalloc(unp_zone); 560 if (unp == NULL) 561 return (ENOBUFS); 562 bzero(unp, sizeof *unp); 563 unp->unp_gencnt = ++unp_gencnt; 564 unp_count++; 565 LIST_INIT(&unp->unp_refs); 566 unp->unp_socket = so; 567 unp->unp_rvnode = ai->fd_rdir; /* jail cruft XXX JH */ 568 LIST_INSERT_HEAD(so->so_type == SOCK_DGRAM ? &unp_dhead 569 : &unp_shead, unp, unp_link); 570 so->so_pcb = (caddr_t)unp; 571 return (0); 572 } 573 574 static void 575 unp_detach(struct unpcb *unp) 576 { 577 LIST_REMOVE(unp, unp_link); 578 unp->unp_gencnt = ++unp_gencnt; 579 --unp_count; 580 if (unp->unp_vnode) { 581 unp->unp_vnode->v_socket = NULL; 582 vrele(unp->unp_vnode); 583 unp->unp_vnode = NULL; 584 } 585 if (unp->unp_conn) 586 unp_disconnect(unp); 587 while (!LIST_EMPTY(&unp->unp_refs)) 588 unp_drop(LIST_FIRST(&unp->unp_refs), ECONNRESET); 589 soisdisconnected(unp->unp_socket); 590 unp->unp_socket->so_pcb = NULL; 591 if (unp_rights) { 592 /* 593 * Normally the receive buffer is flushed later, 594 * in sofree, but if our receive buffer holds references 595 * to descriptors that are now garbage, we will dispose 596 * of those descriptor references after the garbage collector 597 * gets them (resulting in a "panic: closef: count < 0"). 598 */ 599 sorflush(unp->unp_socket); 600 unp_gc(); 601 } 602 if (unp->unp_addr) 603 kfree(unp->unp_addr, M_SONAME); 604 zfree(unp_zone, unp); 605 } 606 607 static int 608 unp_bind(struct unpcb *unp, struct sockaddr *nam, struct thread *td) 609 { 610 struct proc *p = td->td_proc; 611 struct sockaddr_un *soun = (struct sockaddr_un *)nam; 612 struct vnode *vp; 613 struct vattr vattr; 614 int error, namelen; 615 struct nlookupdata nd; 616 char buf[SOCK_MAXADDRLEN]; 617 618 if (unp->unp_vnode != NULL) 619 return (EINVAL); 620 namelen = soun->sun_len - offsetof(struct sockaddr_un, sun_path); 621 if (namelen <= 0) 622 return (EINVAL); 623 strncpy(buf, soun->sun_path, namelen); 624 buf[namelen] = 0; /* null-terminate the string */ 625 error = nlookup_init(&nd, buf, UIO_SYSSPACE, 626 NLC_LOCKVP | NLC_CREATE | NLC_REFDVP); 627 if (error == 0) 628 error = nlookup(&nd); 629 if (error == 0 && nd.nl_nch.ncp->nc_vp != NULL) 630 error = EADDRINUSE; 631 if (error) 632 goto done; 633 634 VATTR_NULL(&vattr); 635 vattr.va_type = VSOCK; 636 vattr.va_mode = (ACCESSPERMS & ~p->p_fd->fd_cmask); 637 error = VOP_NCREATE(&nd.nl_nch, nd.nl_dvp, &vp, nd.nl_cred, &vattr); 638 if (error == 0) { 639 vp->v_socket = unp->unp_socket; 640 unp->unp_vnode = vp; 641 unp->unp_addr = (struct sockaddr_un *)dup_sockaddr(nam); 642 vn_unlock(vp); 643 } 644 done: 645 nlookup_done(&nd); 646 return (error); 647 } 648 649 static int 650 unp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 651 { 652 struct proc *p = td->td_proc; 653 struct sockaddr_un *soun = (struct sockaddr_un *)nam; 654 struct vnode *vp; 655 struct socket *so2, *so3; 656 struct unpcb *unp, *unp2, *unp3; 657 int error, len; 658 struct nlookupdata nd; 659 char buf[SOCK_MAXADDRLEN]; 660 661 KKASSERT(p); 662 663 len = nam->sa_len - offsetof(struct sockaddr_un, sun_path); 664 if (len <= 0) 665 return EINVAL; 666 strncpy(buf, soun->sun_path, len); 667 buf[len] = 0; 668 669 vp = NULL; 670 error = nlookup_init(&nd, buf, UIO_SYSSPACE, NLC_FOLLOW); 671 if (error == 0) 672 error = nlookup(&nd); 673 if (error == 0) 674 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp); 675 nlookup_done(&nd); 676 if (error) 677 return (error); 678 679 if (vp->v_type != VSOCK) { 680 error = ENOTSOCK; 681 goto bad; 682 } 683 error = VOP_ACCESS(vp, VWRITE, p->p_ucred); 684 if (error) 685 goto bad; 686 so2 = vp->v_socket; 687 if (so2 == NULL) { 688 error = ECONNREFUSED; 689 goto bad; 690 } 691 if (so->so_type != so2->so_type) { 692 error = EPROTOTYPE; 693 goto bad; 694 } 695 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 696 if (!(so2->so_options & SO_ACCEPTCONN) || 697 (so3 = sonewconn(so2, 0)) == NULL) { 698 error = ECONNREFUSED; 699 goto bad; 700 } 701 unp = so->so_pcb; 702 unp2 = so2->so_pcb; 703 unp3 = so3->so_pcb; 704 if (unp2->unp_addr) 705 unp3->unp_addr = (struct sockaddr_un *) 706 dup_sockaddr((struct sockaddr *)unp2->unp_addr); 707 708 /* 709 * unp_peercred management: 710 * 711 * The connecter's (client's) credentials are copied 712 * from its process structure at the time of connect() 713 * (which is now). 714 */ 715 cru2x(p->p_ucred, &unp3->unp_peercred); 716 unp3->unp_flags |= UNP_HAVEPC; 717 /* 718 * The receiver's (server's) credentials are copied 719 * from the unp_peercred member of socket on which the 720 * former called listen(); unp_listen() cached that 721 * process's credentials at that time so we can use 722 * them now. 723 */ 724 KASSERT(unp2->unp_flags & UNP_HAVEPCCACHED, 725 ("unp_connect: listener without cached peercred")); 726 memcpy(&unp->unp_peercred, &unp2->unp_peercred, 727 sizeof(unp->unp_peercred)); 728 unp->unp_flags |= UNP_HAVEPC; 729 730 so2 = so3; 731 } 732 error = unp_connect2(so, so2); 733 bad: 734 vput(vp); 735 return (error); 736 } 737 738 int 739 unp_connect2(struct socket *so, struct socket *so2) 740 { 741 struct unpcb *unp = so->so_pcb; 742 struct unpcb *unp2; 743 744 if (so2->so_type != so->so_type) 745 return (EPROTOTYPE); 746 unp2 = so2->so_pcb; 747 unp->unp_conn = unp2; 748 switch (so->so_type) { 749 750 case SOCK_DGRAM: 751 LIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_reflink); 752 soisconnected(so); 753 break; 754 755 case SOCK_STREAM: 756 unp2->unp_conn = unp; 757 soisconnected(so); 758 soisconnected(so2); 759 break; 760 761 default: 762 panic("unp_connect2"); 763 } 764 return (0); 765 } 766 767 static void 768 unp_disconnect(struct unpcb *unp) 769 { 770 struct unpcb *unp2 = unp->unp_conn; 771 772 if (unp2 == NULL) 773 return; 774 775 unp->unp_conn = NULL; 776 777 switch (unp->unp_socket->so_type) { 778 case SOCK_DGRAM: 779 LIST_REMOVE(unp, unp_reflink); 780 unp->unp_socket->so_state &= ~SS_ISCONNECTED; 781 break; 782 case SOCK_STREAM: 783 soisdisconnected(unp->unp_socket); 784 unp2->unp_conn = NULL; 785 soisdisconnected(unp2->unp_socket); 786 break; 787 } 788 } 789 790 #ifdef notdef 791 void 792 unp_abort(struct unpcb *unp) 793 { 794 795 unp_detach(unp); 796 } 797 #endif 798 799 static int 800 prison_unpcb(struct thread *td, struct unpcb *unp) 801 { 802 struct proc *p; 803 804 if (td == NULL) 805 return (0); 806 if ((p = td->td_proc) == NULL) 807 return (0); 808 if (!p->p_ucred->cr_prison) 809 return (0); 810 if (p->p_fd->fd_rdir == unp->unp_rvnode) 811 return (0); 812 return (1); 813 } 814 815 static int 816 unp_pcblist(SYSCTL_HANDLER_ARGS) 817 { 818 int error, i, n; 819 struct unpcb *unp, **unp_list; 820 unp_gen_t gencnt; 821 struct unp_head *head; 822 823 head = ((intptr_t)arg1 == SOCK_DGRAM ? &unp_dhead : &unp_shead); 824 825 KKASSERT(curproc != NULL); 826 827 /* 828 * The process of preparing the PCB list is too time-consuming and 829 * resource-intensive to repeat twice on every request. 830 */ 831 if (req->oldptr == NULL) { 832 n = unp_count; 833 req->oldidx = (n + n/8) * sizeof(struct xunpcb); 834 return 0; 835 } 836 837 if (req->newptr != NULL) 838 return EPERM; 839 840 /* 841 * OK, now we're committed to doing something. 842 */ 843 gencnt = unp_gencnt; 844 n = unp_count; 845 846 unp_list = kmalloc(n * sizeof *unp_list, M_TEMP, M_WAITOK); 847 848 for (unp = LIST_FIRST(head), i = 0; unp && i < n; 849 unp = LIST_NEXT(unp, unp_link)) { 850 if (unp->unp_gencnt <= gencnt && !prison_unpcb(req->td, unp)) 851 unp_list[i++] = unp; 852 } 853 n = i; /* in case we lost some during malloc */ 854 855 error = 0; 856 for (i = 0; i < n; i++) { 857 unp = unp_list[i]; 858 if (unp->unp_gencnt <= gencnt) { 859 struct xunpcb xu; 860 xu.xu_len = sizeof xu; 861 xu.xu_unpp = unp; 862 /* 863 * XXX - need more locking here to protect against 864 * connect/disconnect races for SMP. 865 */ 866 if (unp->unp_addr) 867 bcopy(unp->unp_addr, &xu.xu_addr, 868 unp->unp_addr->sun_len); 869 if (unp->unp_conn && unp->unp_conn->unp_addr) 870 bcopy(unp->unp_conn->unp_addr, 871 &xu.xu_caddr, 872 unp->unp_conn->unp_addr->sun_len); 873 bcopy(unp, &xu.xu_unp, sizeof *unp); 874 sotoxsocket(unp->unp_socket, &xu.xu_socket); 875 error = SYSCTL_OUT(req, &xu, sizeof xu); 876 } 877 } 878 kfree(unp_list, M_TEMP); 879 return error; 880 } 881 882 SYSCTL_PROC(_net_local_dgram, OID_AUTO, pcblist, CTLFLAG_RD, 883 (caddr_t)(long)SOCK_DGRAM, 0, unp_pcblist, "S,xunpcb", 884 "List of active local datagram sockets"); 885 SYSCTL_PROC(_net_local_stream, OID_AUTO, pcblist, CTLFLAG_RD, 886 (caddr_t)(long)SOCK_STREAM, 0, unp_pcblist, "S,xunpcb", 887 "List of active local stream sockets"); 888 889 static void 890 unp_shutdown(struct unpcb *unp) 891 { 892 struct socket *so; 893 894 if (unp->unp_socket->so_type == SOCK_STREAM && unp->unp_conn != NULL && 895 (so = unp->unp_conn->unp_socket)) 896 socantrcvmore(so); 897 } 898 899 static void 900 unp_drop(struct unpcb *unp, int err) 901 { 902 struct socket *so = unp->unp_socket; 903 904 so->so_error = err; 905 unp_disconnect(unp); 906 } 907 908 #ifdef notdef 909 void 910 unp_drain(void) 911 { 912 913 } 914 #endif 915 916 int 917 unp_externalize(struct mbuf *rights) 918 { 919 struct proc *p = curproc; /* XXX */ 920 int i; 921 struct cmsghdr *cm = mtod(rights, struct cmsghdr *); 922 int *fdp; 923 struct file **rp; 924 struct file *fp; 925 int newfds = (cm->cmsg_len - (CMSG_DATA(cm) - (u_char *)cm)) 926 / sizeof (struct file *); 927 int f; 928 929 /* 930 * if the new FD's will not fit, then we free them all 931 */ 932 if (!fdavail(p, newfds)) { 933 rp = (struct file **)CMSG_DATA(cm); 934 for (i = 0; i < newfds; i++) { 935 fp = *rp; 936 /* 937 * zero the pointer before calling unp_discard, 938 * since it may end up in unp_gc().. 939 */ 940 *rp++ = 0; 941 unp_discard(fp, NULL); 942 } 943 return (EMSGSIZE); 944 } 945 /* 946 * now change each pointer to an fd in the global table to 947 * an integer that is the index to the local fd table entry 948 * that we set up to point to the global one we are transferring. 949 * If sizeof (struct file *) is bigger than or equal to sizeof int, 950 * then do it in forward order. In that case, an integer will 951 * always come in the same place or before its corresponding 952 * struct file pointer. 953 * If sizeof (struct file *) is smaller than sizeof int, then 954 * do it in reverse order. 955 */ 956 if (sizeof (struct file *) >= sizeof (int)) { 957 fdp = (int *)(cm + 1); 958 rp = (struct file **)CMSG_DATA(cm); 959 for (i = 0; i < newfds; i++) { 960 if (fdalloc(p, 0, &f)) 961 panic("unp_externalize"); 962 fp = *rp++; 963 fsetfd(p, fp, f); 964 fdrop(fp); 965 spin_lock_wr(&unp_spin); 966 fp->f_msgcount--; 967 unp_rights--; 968 spin_unlock_wr(&unp_spin); 969 *fdp++ = f; 970 } 971 } else { 972 fdp = (int *)(cm + 1) + newfds - 1; 973 rp = (struct file **)CMSG_DATA(cm) + newfds - 1; 974 for (i = 0; i < newfds; i++) { 975 if (fdalloc(p, 0, &f)) 976 panic("unp_externalize"); 977 fp = *rp--; 978 fsetfd(p, fp, f); 979 fdrop(fp); 980 spin_lock_wr(&unp_spin); 981 fp->f_msgcount--; 982 unp_rights--; 983 spin_unlock_wr(&unp_spin); 984 *fdp-- = f; 985 } 986 } 987 988 /* 989 * Adjust length, in case sizeof(struct file *) and sizeof(int) 990 * differs. 991 */ 992 cm->cmsg_len = CMSG_LEN(newfds * sizeof(int)); 993 rights->m_len = cm->cmsg_len; 994 return (0); 995 } 996 997 void 998 unp_init(void) 999 { 1000 unp_zone = zinit("unpcb", sizeof(struct unpcb), nmbclusters, 0, 0); 1001 if (unp_zone == NULL) 1002 panic("unp_init"); 1003 LIST_INIT(&unp_dhead); 1004 LIST_INIT(&unp_shead); 1005 spin_init(&unp_spin); 1006 } 1007 1008 static int 1009 unp_internalize(struct mbuf *control, struct thread *td) 1010 { 1011 struct proc *p = td->td_proc; 1012 struct filedesc *fdescp; 1013 struct cmsghdr *cm = mtod(control, struct cmsghdr *); 1014 struct file **rp; 1015 struct file *fp; 1016 int i, fd, *fdp; 1017 struct cmsgcred *cmcred; 1018 int oldfds; 1019 u_int newlen; 1020 1021 KKASSERT(p); 1022 fdescp = p->p_fd; 1023 if ((cm->cmsg_type != SCM_RIGHTS && cm->cmsg_type != SCM_CREDS) || 1024 cm->cmsg_level != SOL_SOCKET || cm->cmsg_len != control->m_len) 1025 return (EINVAL); 1026 1027 /* 1028 * Fill in credential information. 1029 */ 1030 if (cm->cmsg_type == SCM_CREDS) { 1031 cmcred = (struct cmsgcred *)(cm + 1); 1032 cmcred->cmcred_pid = p->p_pid; 1033 cmcred->cmcred_uid = p->p_ucred->cr_ruid; 1034 cmcred->cmcred_gid = p->p_ucred->cr_rgid; 1035 cmcred->cmcred_euid = p->p_ucred->cr_uid; 1036 cmcred->cmcred_ngroups = MIN(p->p_ucred->cr_ngroups, 1037 CMGROUP_MAX); 1038 for (i = 0; i < cmcred->cmcred_ngroups; i++) 1039 cmcred->cmcred_groups[i] = p->p_ucred->cr_groups[i]; 1040 return(0); 1041 } 1042 1043 oldfds = (cm->cmsg_len - sizeof (*cm)) / sizeof (int); 1044 /* 1045 * check that all the FDs passed in refer to legal OPEN files 1046 * If not, reject the entire operation. 1047 */ 1048 fdp = (int *)(cm + 1); 1049 for (i = 0; i < oldfds; i++) { 1050 fd = *fdp++; 1051 if ((unsigned)fd >= fdescp->fd_nfiles || 1052 fdescp->fd_files[fd].fp == NULL) 1053 return (EBADF); 1054 if (fdescp->fd_files[fd].fp->f_type == DTYPE_KQUEUE) 1055 return (EOPNOTSUPP); 1056 } 1057 /* 1058 * Now replace the integer FDs with pointers to 1059 * the associated global file table entry.. 1060 * Allocate a bigger buffer as necessary. But if an cluster is not 1061 * enough, return E2BIG. 1062 */ 1063 newlen = CMSG_LEN(oldfds * sizeof(struct file *)); 1064 if (newlen > MCLBYTES) 1065 return (E2BIG); 1066 if (newlen - control->m_len > M_TRAILINGSPACE(control)) { 1067 if (control->m_flags & M_EXT) 1068 return (E2BIG); 1069 MCLGET(control, MB_WAIT); 1070 if (!(control->m_flags & M_EXT)) 1071 return (ENOBUFS); 1072 1073 /* copy the data to the cluster */ 1074 memcpy(mtod(control, char *), cm, cm->cmsg_len); 1075 cm = mtod(control, struct cmsghdr *); 1076 } 1077 1078 /* 1079 * Adjust length, in case sizeof(struct file *) and sizeof(int) 1080 * differs. 1081 */ 1082 control->m_len = cm->cmsg_len = newlen; 1083 1084 /* 1085 * Transform the file descriptors into struct file pointers. 1086 * If sizeof (struct file *) is bigger than or equal to sizeof int, 1087 * then do it in reverse order so that the int won't get until 1088 * we're done. 1089 * If sizeof (struct file *) is smaller than sizeof int, then 1090 * do it in forward order. 1091 */ 1092 if (sizeof (struct file *) >= sizeof (int)) { 1093 fdp = (int *)(cm + 1) + oldfds - 1; 1094 rp = (struct file **)CMSG_DATA(cm) + oldfds - 1; 1095 for (i = 0; i < oldfds; i++) { 1096 fp = fdescp->fd_files[*fdp--].fp; 1097 *rp-- = fp; 1098 fhold(fp); 1099 spin_lock_wr(&unp_spin); 1100 fp->f_msgcount++; 1101 unp_rights++; 1102 spin_unlock_wr(&unp_spin); 1103 } 1104 } else { 1105 fdp = (int *)(cm + 1); 1106 rp = (struct file **)CMSG_DATA(cm); 1107 for (i = 0; i < oldfds; i++) { 1108 fp = fdescp->fd_files[*fdp++].fp; 1109 *rp++ = fp; 1110 fhold(fp); 1111 spin_lock_wr(&unp_spin); 1112 fp->f_msgcount++; 1113 unp_rights++; 1114 spin_unlock_wr(&unp_spin); 1115 } 1116 } 1117 return (0); 1118 } 1119 1120 /* 1121 * Garbage collect in-transit file descriptors that get lost due to 1122 * loops (i.e. when a socket is sent to another process over itself, 1123 * and more complex situations). 1124 * 1125 * NOT MPSAFE - TODO socket flush code and maybe closef. Rest is MPSAFE. 1126 */ 1127 1128 struct unp_gc_info { 1129 struct file **extra_ref; 1130 struct file *locked_fp; 1131 int defer; 1132 int index; 1133 int maxindex; 1134 }; 1135 1136 static void 1137 unp_gc(void) 1138 { 1139 struct unp_gc_info info; 1140 static boolean_t unp_gcing; 1141 struct file **fpp; 1142 int i; 1143 1144 spin_lock_wr(&unp_spin); 1145 if (unp_gcing) { 1146 spin_unlock_wr(&unp_spin); 1147 return; 1148 } 1149 unp_gcing = TRUE; 1150 spin_unlock_wr(&unp_spin); 1151 1152 /* 1153 * before going through all this, set all FDs to 1154 * be NOT defered and NOT externally accessible 1155 */ 1156 info.defer = 0; 1157 allfiles_scan_exclusive(unp_gc_clearmarks, NULL); 1158 do { 1159 allfiles_scan_exclusive(unp_gc_checkmarks, &info); 1160 } while (info.defer); 1161 1162 /* 1163 * We grab an extra reference to each of the file table entries 1164 * that are not otherwise accessible and then free the rights 1165 * that are stored in messages on them. 1166 * 1167 * The bug in the orginal code is a little tricky, so I'll describe 1168 * what's wrong with it here. 1169 * 1170 * It is incorrect to simply unp_discard each entry for f_msgcount 1171 * times -- consider the case of sockets A and B that contain 1172 * references to each other. On a last close of some other socket, 1173 * we trigger a gc since the number of outstanding rights (unp_rights) 1174 * is non-zero. If during the sweep phase the gc code un_discards, 1175 * we end up doing a (full) closef on the descriptor. A closef on A 1176 * results in the following chain. Closef calls soo_close, which 1177 * calls soclose. Soclose calls first (through the switch 1178 * uipc_usrreq) unp_detach, which re-invokes unp_gc. Unp_gc simply 1179 * returns because the previous instance had set unp_gcing, and 1180 * we return all the way back to soclose, which marks the socket 1181 * with SS_NOFDREF, and then calls sofree. Sofree calls sorflush 1182 * to free up the rights that are queued in messages on the socket A, 1183 * i.e., the reference on B. The sorflush calls via the dom_dispose 1184 * switch unp_dispose, which unp_scans with unp_discard. This second 1185 * instance of unp_discard just calls closef on B. 1186 * 1187 * Well, a similar chain occurs on B, resulting in a sorflush on B, 1188 * which results in another closef on A. Unfortunately, A is already 1189 * being closed, and the descriptor has already been marked with 1190 * SS_NOFDREF, and soclose panics at this point. 1191 * 1192 * Here, we first take an extra reference to each inaccessible 1193 * descriptor. Then, we call sorflush ourself, since we know 1194 * it is a Unix domain socket anyhow. After we destroy all the 1195 * rights carried in messages, we do a last closef to get rid 1196 * of our extra reference. This is the last close, and the 1197 * unp_detach etc will shut down the socket. 1198 * 1199 * 91/09/19, bsy@cs.cmu.edu 1200 */ 1201 info.extra_ref = kmalloc(256 * sizeof(struct file *), M_FILE, M_WAITOK); 1202 info.maxindex = 256; 1203 1204 do { 1205 /* 1206 * Look for matches 1207 */ 1208 info.index = 0; 1209 allfiles_scan_exclusive(unp_gc_checkrefs, &info); 1210 1211 /* 1212 * For each FD on our hit list, do the following two things 1213 */ 1214 for (i = info.index, fpp = info.extra_ref; --i >= 0; ++fpp) { 1215 struct file *tfp = *fpp; 1216 if (tfp->f_type == DTYPE_SOCKET && tfp->f_data != NULL) 1217 sorflush((struct socket *)(tfp->f_data)); 1218 } 1219 for (i = info.index, fpp = info.extra_ref; --i >= 0; ++fpp) 1220 closef(*fpp, NULL); 1221 } while (info.index == info.maxindex); 1222 kfree((caddr_t)info.extra_ref, M_FILE); 1223 unp_gcing = FALSE; 1224 } 1225 1226 /* 1227 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry 1228 */ 1229 static int 1230 unp_gc_checkrefs(struct file *fp, void *data) 1231 { 1232 struct unp_gc_info *info = data; 1233 1234 if (fp->f_count == 0) 1235 return(0); 1236 if (info->index == info->maxindex) 1237 return(-1); 1238 1239 /* 1240 * If all refs are from msgs, and it's not marked accessible 1241 * then it must be referenced from some unreachable cycle 1242 * of (shut-down) FDs, so include it in our 1243 * list of FDs to remove 1244 */ 1245 if (fp->f_count == fp->f_msgcount && !(fp->f_flag & FMARK)) { 1246 info->extra_ref[info->index++] = fp; 1247 fhold(fp); 1248 } 1249 return(0); 1250 } 1251 1252 /* 1253 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry 1254 */ 1255 static int 1256 unp_gc_clearmarks(struct file *fp, void *data __unused) 1257 { 1258 fp->f_flag &= ~(FMARK|FDEFER); 1259 return(0); 1260 } 1261 1262 /* 1263 * MPSAFE - NOTE: filehead list and file pointer spinlocked on entry 1264 */ 1265 static int 1266 unp_gc_checkmarks(struct file *fp, void *data) 1267 { 1268 struct unp_gc_info *info = data; 1269 struct socket *so; 1270 1271 /* 1272 * If the file is not open, skip it 1273 */ 1274 if (fp->f_count == 0) 1275 return(0); 1276 /* 1277 * If we already marked it as 'defer' in a 1278 * previous pass, then try process it this time 1279 * and un-mark it 1280 */ 1281 if (fp->f_flag & FDEFER) { 1282 fp->f_flag &= ~FDEFER; 1283 --info->defer; 1284 } else { 1285 /* 1286 * if it's not defered, then check if it's 1287 * already marked.. if so skip it 1288 */ 1289 if (fp->f_flag & FMARK) 1290 return(0); 1291 /* 1292 * If all references are from messages 1293 * in transit, then skip it. it's not 1294 * externally accessible. 1295 */ 1296 if (fp->f_count == fp->f_msgcount) 1297 return(0); 1298 /* 1299 * If it got this far then it must be 1300 * externally accessible. 1301 */ 1302 fp->f_flag |= FMARK; 1303 } 1304 /* 1305 * either it was defered, or it is externally 1306 * accessible and not already marked so. 1307 * Now check if it is possibly one of OUR sockets. 1308 */ 1309 if (fp->f_type != DTYPE_SOCKET || 1310 (so = (struct socket *)fp->f_data) == NULL) 1311 return(0); 1312 if (so->so_proto->pr_domain != &localdomain || 1313 !(so->so_proto->pr_flags & PR_RIGHTS)) 1314 return(0); 1315 #ifdef notdef 1316 XXX note: exclusive fp->f_spin lock held 1317 if (so->so_rcv.sb_flags & SB_LOCK) { 1318 /* 1319 * This is problematical; it's not clear 1320 * we need to wait for the sockbuf to be 1321 * unlocked (on a uniprocessor, at least), 1322 * and it's also not clear what to do 1323 * if sbwait returns an error due to receipt 1324 * of a signal. If sbwait does return 1325 * an error, we'll go into an infinite 1326 * loop. Delete all of this for now. 1327 */ 1328 sbwait(&so->so_rcv); 1329 goto restart; 1330 } 1331 #endif 1332 /* 1333 * So, Ok, it's one of our sockets and it IS externally 1334 * accessible (or was defered). Now we look 1335 * to see if we hold any file descriptors in its 1336 * message buffers. Follow those links and mark them 1337 * as accessible too. 1338 */ 1339 info->locked_fp = fp; 1340 /* spin_lock_wr(&so->so_rcv.sb_spin); */ 1341 unp_scan(so->so_rcv.ssb_mb, unp_mark, info); 1342 /* spin_unlock_wr(&so->so_rcv.sb_spin);*/ 1343 return (0); 1344 } 1345 1346 void 1347 unp_dispose(struct mbuf *m) 1348 { 1349 if (m) 1350 unp_scan(m, unp_discard, NULL); 1351 } 1352 1353 static int 1354 unp_listen(struct unpcb *unp, struct thread *td) 1355 { 1356 struct proc *p = td->td_proc; 1357 1358 KKASSERT(p); 1359 cru2x(p->p_ucred, &unp->unp_peercred); 1360 unp->unp_flags |= UNP_HAVEPCCACHED; 1361 return (0); 1362 } 1363 1364 static void 1365 unp_scan(struct mbuf *m0, void (*op)(struct file *, void *), void *data) 1366 { 1367 struct mbuf *m; 1368 struct file **rp; 1369 struct cmsghdr *cm; 1370 int i; 1371 int qfds; 1372 1373 while (m0) { 1374 for (m = m0; m; m = m->m_next) { 1375 if (m->m_type == MT_CONTROL && 1376 m->m_len >= sizeof(*cm)) { 1377 cm = mtod(m, struct cmsghdr *); 1378 if (cm->cmsg_level != SOL_SOCKET || 1379 cm->cmsg_type != SCM_RIGHTS) 1380 continue; 1381 qfds = (cm->cmsg_len - 1382 (CMSG_DATA(cm) - (u_char *)cm)) 1383 / sizeof (struct file *); 1384 rp = (struct file **)CMSG_DATA(cm); 1385 for (i = 0; i < qfds; i++) 1386 (*op)(*rp++, data); 1387 break; /* XXX, but saves time */ 1388 } 1389 } 1390 m0 = m0->m_nextpkt; 1391 } 1392 } 1393 1394 static void 1395 unp_mark(struct file *fp, void *data) 1396 { 1397 struct unp_gc_info *info = data; 1398 1399 if (info->locked_fp != fp) 1400 spin_lock_wr(&fp->f_spin); 1401 if ((fp->f_flag & FMARK) == 0) { 1402 ++info->defer; 1403 fp->f_flag |= (FMARK|FDEFER); 1404 } 1405 if (info->locked_fp != fp) 1406 spin_unlock_wr(&fp->f_spin); 1407 } 1408 1409 static void 1410 unp_discard(struct file *fp, void *data __unused) 1411 { 1412 spin_lock_wr(&unp_spin); 1413 fp->f_msgcount--; 1414 unp_rights--; 1415 spin_unlock_wr(&unp_spin); 1416 closef(fp, NULL); 1417 } 1418 1419