FreeBSD-6.3-src.patch 48.1 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426
diff --exclude=CVS -r -u 6.3-release/src/UPDATING 6.3-patched/src/UPDATING
--- 6.3-release/src/UPDATING	Tue Jan 15 08:45:07 2008
+++ 6.3-patched/src/UPDATING	Tue Aug 19 12:11:20 2008
@@ -8,6 +8,19 @@
 /usr/ports/UPDATING.  Please read that file before running
 portupgrade.
 
+20080713:	p3	FreeBSD-SA-08:06.bind
+	Improve randomization in BIND to prevent response spoofing.
+
+20080416:	p2	FreeBSD-SA-08:05.openssh,
+			FreeBSD-EN-08:01.libpthread
+	Fix logic error in sshd(8) concerning the handling of failed
+	attempts to bind ports for X11 forwarding. [SA-08:05]
+
+	Fix issued with threaded programs calling fork(2). [EN-08:01]
+
+20080214:	p1	FreeBSD-SA-08:02.sendfile
+	Fix sendfile(2) write-only file permission bypass.
+
 20080118:
 	FreeBSD 6.3-RELEASE
 
@@ -566,4 +579,4 @@
 Contact Warner Losh if you have any questions about your use of
 this document.
 
-$FreeBSD: src/UPDATING,v 1.416.2.37.2.4 2008/01/15 15:45:07 kensmith Exp $
+$FreeBSD: src/UPDATING,v 1.416.2.37.2.8 2008/07/13 18:42:38 cperciva Exp $
diff --exclude=CVS -r -u 6.3-release/src/contrib/bind9/bin/named/client.c 6.3-patched/src/contrib/bind9/bin/named/client.c
--- 6.3-release/src/contrib/bind9/bin/named/client.c	Wed Jul 25 02:23:07 2007
+++ 6.3-patched/src/contrib/bind9/bin/named/client.c	Tue Aug 19 12:11:49 2008
@@ -1349,14 +1349,6 @@
 	}
 
 	/*
-	 * Hash the incoming request here as it is after
-	 * dns_dispatch_importrecv().
-	 */
-	dns_dispatch_hash(&client->now, sizeof(client->now));
-	dns_dispatch_hash(isc_buffer_base(buffer),
-			  isc_buffer_usedlength(buffer));
-
-	/*
 	 * It's a request.  Parse it.
 	 */
 	result = dns_message_parse(client->message, buffer, 0);
diff --exclude=CVS -r -u 6.3-release/src/contrib/bind9/bin/named/server.c 6.3-patched/src/contrib/bind9/bin/named/server.c
--- 6.3-release/src/contrib/bind9/bin/named/server.c	Wed Dec 13 02:46:50 2006
+++ 6.3-patched/src/contrib/bind9/bin/named/server.c	Tue Aug 19 12:11:50 2008
@@ -477,6 +477,14 @@
 		attrs |= DNS_DISPATCHATTR_IPV6;
 		break;
 	}
+
+	if (isc_sockaddr_getport(&sa) != 0) {
+		INSIST(obj != NULL);
+		cfg_obj_log(obj, ns_g_lctx, ISC_LOG_INFO,
+			    "using specific query-source port suppresses port "
+			    "randomization and can be insecure.");
+	}
+
 	attrmask = 0;
 	attrmask |= DNS_DISPATCHATTR_UDP;
 	attrmask |= DNS_DISPATCHATTR_TCP;
@@ -486,7 +494,7 @@
 	disp = NULL;
 	result = dns_dispatch_getudp(ns_g_dispatchmgr, ns_g_socketmgr,
 				     ns_g_taskmgr, &sa, 4096,
-				     1000, 32768, 16411, 16433,
+				     1024, 32768, 16411, 16433,
 				     attrs, attrmask, &disp);
 	if (result != ISC_R_SUCCESS) {
 		isc_sockaddr_t any;
@@ -1858,7 +1866,9 @@
 }
 
 static isc_result_t
-add_listenelt(isc_mem_t *mctx, ns_listenlist_t *list, isc_sockaddr_t *addr) {
+add_listenelt(isc_mem_t *mctx, ns_listenlist_t *list, isc_sockaddr_t *addr,
+	      isc_boolean_t wcardport_ok)
+{
 	ns_listenelt_t *lelt = NULL;
 	dns_acl_t *src_acl = NULL;
 	dns_aclelement_t aelt;
@@ -1868,7 +1878,8 @@
 	REQUIRE(isc_sockaddr_pf(addr) == AF_INET6);
 
 	isc_sockaddr_any6(&any_sa6);
-	if (!isc_sockaddr_equal(&any_sa6, addr)) {
+	if (!isc_sockaddr_equal(&any_sa6, addr) &&
+	    (wcardport_ok || isc_sockaddr_getport(addr) != 0)) {
 		aelt.type = dns_aclelementtype_ipprefix;
 		aelt.negative = ISC_FALSE;
 		aelt.u.ip_prefix.prefixlen = 128;
@@ -1927,7 +1938,16 @@
 		result = dns_dispatch_getlocaladdress(dispatch6, &addr);
 		if (result != ISC_R_SUCCESS)
 			goto fail;
-		result = add_listenelt(mctx, list, &addr);
+
+		/*
+		 * We always add non-wildcard address regardless of whether
+		 * the port is 'any' (the fourth arg is TRUE): if the port is
+		 * specific, we need to add it since it may conflict with a
+		 * listening interface; if it's zero, we'll dynamically open
+		 * query ports, and some of them may override an existing
+		 * wildcard IPv6 port.
+		 */
+		result = add_listenelt(mctx, list, &addr, ISC_TRUE);
 		if (result != ISC_R_SUCCESS)
 			goto fail;
 	}
@@ -1957,12 +1977,12 @@
 			continue;
 
 		addrp = dns_zone_getnotifysrc6(zone);
-		result = add_listenelt(mctx, list, addrp);
+		result = add_listenelt(mctx, list, addrp, ISC_FALSE);
 		if (result != ISC_R_SUCCESS)
 			goto fail;
 
 		addrp = dns_zone_getxfrsource6(zone);
-		result = add_listenelt(mctx, list, addrp);
+		result = add_listenelt(mctx, list, addrp, ISC_FALSE);
 		if (result != ISC_R_SUCCESS)
 			goto fail;
 	}
diff --exclude=CVS -r -u 6.3-release/src/contrib/bind9/lib/dns/api 6.3-patched/src/contrib/bind9/lib/dns/api
--- 6.3-release/src/contrib/bind9/lib/dns/api	Tue Feb  6 17:42:08 2007
+++ 6.3-patched/src/contrib/bind9/lib/dns/api	Tue Aug 19 12:11:53 2008
@@ -1,3 +1,3 @@
-LIBINTERFACE = 23
-LIBREVISION = 0
-LIBAGE = 1
+LIBINTERFACE = 24
+LIBREVISION = 2
+LIBAGE = 2
diff --exclude=CVS -r -u 6.3-release/src/contrib/bind9/lib/dns/dispatch.c 6.3-patched/src/contrib/bind9/lib/dns/dispatch.c
--- 6.3-release/src/contrib/bind9/lib/dns/dispatch.c	Wed Jul 25 02:23:07 2007
+++ 6.3-patched/src/contrib/bind9/lib/dns/dispatch.c	Tue Aug 19 12:11:53 2008
@@ -27,6 +27,7 @@
 #include <isc/mem.h>
 #include <isc/mutex.h>
 #include <isc/print.h>
+#include <isc/random.h>
 #include <isc/string.h>
 #include <isc/task.h>
 #include <isc/time.h>
@@ -43,25 +44,22 @@
 
 typedef ISC_LIST(dns_dispentry_t)	dns_displist_t;
 
-typedef struct dns_nsid {
-	isc_uint16_t	nsid_state;
-	isc_uint16_t	*nsid_vtable;
-	isc_uint16_t	*nsid_pool;
-	isc_uint16_t	nsid_a1, nsid_a2, nsid_a3;
-	isc_uint16_t	nsid_c1, nsid_c2, nsid_c3;
-	isc_uint16_t	nsid_state2;
-	isc_boolean_t	nsid_usepool;
-} dns_nsid_t;
-
 typedef struct dns_qid {
 	unsigned int	magic;
 	unsigned int	qid_nbuckets;	/* hash table size */
 	unsigned int	qid_increment;	/* id increment on collision */
 	isc_mutex_t	lock;
-	dns_nsid_t	nsid;
 	dns_displist_t	*qid_table;	/* the table itself */
 } dns_qid_t;
 
+/* ARC4 Random generator state */
+typedef struct arc4ctx {
+	isc_uint8_t	i;
+	isc_uint8_t	j;
+	isc_uint8_t	s[256];
+	int		count;
+} arc4ctx_t;
+
 struct dns_dispatchmgr {
 	/* Unlocked. */
 	unsigned int			magic;
@@ -74,6 +72,10 @@
 	unsigned int			state;
 	ISC_LIST(dns_dispatch_t)	list;
 
+	/* Locked by arc4_lock. */
+	isc_mutex_t			arc4_lock;
+	arc4ctx_t			arc4ctx;    /*%< ARC4 context for QID */
+
 	/* locked by buffer lock */
 	dns_qid_t			*qid;
 	isc_mutex_t			buffer_lock;
@@ -100,6 +102,7 @@
 	unsigned int			magic;
 	dns_dispatch_t		       *disp;
 	dns_messageid_t			id;
+	in_port_t			port;
 	unsigned int			bucket;
 	isc_sockaddr_t			host;
 	isc_task_t		       *task;
@@ -119,6 +122,7 @@
 	isc_task_t	       *task;		/* internal task */
 	isc_socket_t	       *socket;		/* isc socket attached to */
 	isc_sockaddr_t		local;		/* local address */
+	in_port_t		localport;	/* local UDP port */
 	unsigned int		maxrequests;	/* max requests */
 	isc_event_t	       *ctlevent;
 
@@ -161,14 +165,14 @@
  * Statics.
  */
 static dns_dispentry_t *bucket_search(dns_qid_t *, isc_sockaddr_t *,
-				      dns_messageid_t, unsigned int);
+				      dns_messageid_t, in_port_t, unsigned int);
 static isc_boolean_t destroy_disp_ok(dns_dispatch_t *);
 static void destroy_disp(isc_task_t *task, isc_event_t *event);
 static void udp_recv(isc_task_t *, isc_event_t *);
 static void tcp_recv(isc_task_t *, isc_event_t *);
 static void startrecv(dns_dispatch_t *);
-static dns_messageid_t dns_randomid(dns_nsid_t *);
-static isc_uint32_t dns_hash(dns_qid_t *, isc_sockaddr_t *, dns_messageid_t);
+static isc_uint32_t dns_hash(dns_qid_t *, isc_sockaddr_t *, dns_messageid_t,
+			     in_port_t);
 static void free_buffer(dns_dispatch_t *disp, void *buf, unsigned int len);
 static void *allocate_udp_buffer(dns_dispatch_t *disp);
 static inline void free_event(dns_dispatch_t *disp, dns_dispatchevent_t *ev);
@@ -188,12 +192,8 @@
 static isc_boolean_t destroy_mgr_ok(dns_dispatchmgr_t *mgr);
 static void destroy_mgr(dns_dispatchmgr_t **mgrp);
 static isc_result_t qid_allocate(dns_dispatchmgr_t *mgr, unsigned int buckets,
-				 unsigned int increment, isc_boolean_t usepool,
-				 dns_qid_t **qidp);
+				 unsigned int increment, dns_qid_t **qidp);
 static void qid_destroy(isc_mem_t *mctx, dns_qid_t **qidp);
-static isc_uint16_t nsid_next(dns_nsid_t *nsid);
-static isc_result_t nsid_init(isc_mem_t *mctx, dns_nsid_t *nsid, isc_boolean_t usepool);
-static void nsid_destroy(isc_mem_t *mctx, dns_nsid_t *nsid);
 
 #define LVL(x) ISC_LOG_DEBUG(x)
 
@@ -274,26 +274,152 @@
 }
 
 /*
- * Return an unpredictable message ID.
+ * ARC4 random number generator obtained from OpenBSD
  */
-static dns_messageid_t
-dns_randomid(dns_nsid_t *nsid) {
-	isc_uint32_t id;
+static void
+dispatch_arc4init(arc4ctx_t *actx) {
+	int n;
+	for (n = 0; n < 256; n++)
+		actx->s[n] = n;
+	actx->i = 0;
+	actx->j = 0;
+	actx->count = 0;
+}
+
+static void
+dispatch_arc4addrandom(arc4ctx_t *actx, unsigned char *dat, int datlen) {
+	int n;
+	isc_uint8_t si;
+
+	actx->i--;
+	for (n = 0; n < 256; n++) {
+		actx->i = (actx->i + 1);
+		si = actx->s[actx->i];
+		actx->j = (actx->j + si + dat[n % datlen]);
+		actx->s[actx->i] = actx->s[actx->j];
+		actx->s[actx->j] = si;
+	}
+	actx->j = actx->i;
+}
+
+static inline isc_uint8_t
+dispatch_arc4get8(arc4ctx_t *actx) {
+	isc_uint8_t si, sj;
+
+	actx->i = (actx->i + 1);
+	si = actx->s[actx->i];
+	actx->j = (actx->j + si);
+	sj = actx->s[actx->j];
+	actx->s[actx->i] = sj;
+	actx->s[actx->j] = si;
+
+	return (actx->s[(si + sj) & 0xff]);
+}
+
+static inline isc_uint16_t
+dispatch_arc4get16(arc4ctx_t *actx) {
+	isc_uint16_t val;
+
+	val = dispatch_arc4get8(actx) << 8;
+	val |= dispatch_arc4get8(actx);
+
+	return (val);
+}
+
+static void
+dispatch_arc4stir(dns_dispatchmgr_t *mgr) {
+	int i;
+	union {
+		unsigned char rnd[128];
+		isc_uint32_t rnd32[32];
+	} rnd;
+	isc_result_t result;
 
-	id = nsid_next(nsid);
+	if (mgr->entropy != NULL) {
+		/*
+		 * We accept any quality of random data to avoid blocking.
+		 */
+		result = isc_entropy_getdata(mgr->entropy, rnd.rnd,
+					     sizeof(rnd), NULL, 0);
+		RUNTIME_CHECK(result == ISC_R_SUCCESS);
+	} else {
+		for (i = 0; i < 32; i++)
+			isc_random_get(&rnd.rnd32[i]);
+	}
+	dispatch_arc4addrandom(&mgr->arc4ctx, rnd.rnd, sizeof(rnd.rnd));
 
-	return ((dns_messageid_t)id);
+	/*
+	 * Discard early keystream, as per recommendations in:
+	 * http://www.wisdom.weizmann.ac.il/~itsik/RC4/Papers/Rc4_ksa.ps
+	 */
+	for (i = 0; i < 256; i++)
+		(void)dispatch_arc4get8(&mgr->arc4ctx);
+
+	/*
+	 * Derived from OpenBSD's implementation.  The rationale is not clear,
+	 * but should be conservative enough in safety, and reasonably large
+	 * for efficiency.
+	 */
+	mgr->arc4ctx.count = 1600000;
+}
+
+static isc_uint16_t
+dispatch_arc4random(dns_dispatchmgr_t *mgr) {
+	isc_uint16_t result;
+
+	LOCK(&mgr->arc4_lock);
+	mgr->arc4ctx.count -= sizeof(isc_uint16_t);
+	if (mgr->arc4ctx.count <= 0)
+		dispatch_arc4stir(mgr);
+	result = dispatch_arc4get16(&mgr->arc4ctx);
+	UNLOCK(&mgr->arc4_lock);
+	return (result);
+}
+
+static isc_uint16_t
+dispatch_arc4uniformrandom(dns_dispatchmgr_t *mgr, isc_uint16_t upper_bound) {
+	isc_uint16_t min, r;
+	/* The caller must hold the manager lock. */
+
+	if (upper_bound < 2)
+		return (0);
+
+	/*
+	 * Ensure the range of random numbers [min, 0xffff] be a multiple of
+	 * upper_bound and contain at least a half of the 16 bit range.
+	 */
+
+	if (upper_bound > 0x8000)
+		min = 1 + ~upper_bound; /* 0x8000 - upper_bound */
+	else
+		min = (isc_uint16_t)(0x10000 % (isc_uint32_t)upper_bound);
+
+	/*
+	 * This could theoretically loop forever but each retry has
+	 * p > 0.5 (worst case, usually far better) of selecting a
+	 * number inside the range we need, so it should rarely need
+	 * to re-roll.
+	 */
+	for (;;) {
+		r = dispatch_arc4random(mgr);
+		if (r >= min)
+			break;
+	}
+
+	return (r % upper_bound);
 }
 
 /*
  * Return a hash of the destination and message id.
  */
 static isc_uint32_t
-dns_hash(dns_qid_t *qid, isc_sockaddr_t *dest, dns_messageid_t id) {
+dns_hash(dns_qid_t *qid, isc_sockaddr_t *dest, dns_messageid_t id,
+	 in_port_t port)
+{
 	unsigned int ret;
 
 	ret = isc_sockaddr_hash(dest, ISC_TRUE);
-	ret ^= id;
+	ret ^= (id << 16) | port;
 	ret %= qid->qid_nbuckets;
 
 	INSIST(ret < qid->qid_nbuckets);
@@ -410,7 +536,7 @@
  */
 static dns_dispentry_t *
 bucket_search(dns_qid_t *qid, isc_sockaddr_t *dest, dns_messageid_t id,
-	      unsigned int bucket)
+	      in_port_t port, unsigned int bucket)
 {
 	dns_dispentry_t *res;
 
@@ -419,8 +545,10 @@
 	res = ISC_LIST_HEAD(qid->qid_table[bucket]);
 
 	while (res != NULL) {
-		if ((res->id == id) && isc_sockaddr_equal(dest, &res->host))
+		if ((res->id == id) && isc_sockaddr_equal(dest, &res->host) &&
+		    res->port == port) {
 			return (res);
+		}
 		res = ISC_LIST_NEXT(res, link);
 	}
 
@@ -622,13 +750,10 @@
 		goto restart;
 	}
 
-	dns_dispatch_hash(&ev->timestamp, sizeof(&ev->timestamp));
-	dns_dispatch_hash(ev->region.base, ev->region.length);
-
 	/* response */
-	bucket = dns_hash(qid, &ev->address, id);
+	bucket = dns_hash(qid, &ev->address, id, disp->localport);
 	LOCK(&qid->lock);
-	resp = bucket_search(qid, &ev->address, id, bucket);
+	resp = bucket_search(qid, &ev->address, id, disp->localport, bucket);
 	dispatch_log(disp, LVL(90),
 		     "search for response in bucket %d: %s",
 		     bucket, (resp == NULL ? "not found" : "found"));
@@ -859,14 +984,13 @@
 		goto restart;
 	}
 
-	dns_dispatch_hash(tcpmsg->buffer.base, tcpmsg->buffer.length);
-
 	/*
 	 * Response.
 	 */
-	bucket = dns_hash(qid, &tcpmsg->address, id);
+	bucket = dns_hash(qid, &tcpmsg->address, id, disp->localport);
 	LOCK(&qid->lock);
-	resp = bucket_search(qid, &tcpmsg->address, id, bucket);
+	resp = bucket_search(qid, &tcpmsg->address, id, disp->localport,
+			     bucket);
 	dispatch_log(disp, LVL(90),
 		     "search for response in bucket %d: %s",
 		     bucket, (resp == NULL ? "not found" : "found"));
@@ -1015,6 +1139,8 @@
 	DESTROYLOCK(&mgr->lock);
 	mgr->state = 0;
 
+	DESTROYLOCK(&mgr->arc4_lock);
+
 	isc_mempool_destroy(&mgr->epool);
 	isc_mempool_destroy(&mgr->rpool);
 	isc_mempool_destroy(&mgr->dpool);
@@ -1093,10 +1219,14 @@
 	if (result != ISC_R_SUCCESS)
 		goto deallocate;
 
-	result = isc_mutex_init(&mgr->buffer_lock);
+	result = isc_mutex_init(&mgr->arc4_lock);
 	if (result != ISC_R_SUCCESS)
 		goto kill_lock;
 
+	result = isc_mutex_init(&mgr->buffer_lock);
+	if (result != ISC_R_SUCCESS)
+		goto kill_arc4_lock;
+
 	result = isc_mutex_init(&mgr->pool_lock);
 	if (result != ISC_R_SUCCESS)
 		goto kill_buffer_lock;
@@ -1147,6 +1277,8 @@
 	if (entropy != NULL)
 		isc_entropy_attach(entropy, &mgr->entropy);
 
+	dispatch_arc4init(&mgr->arc4ctx);
+
 	*mgrp = mgr;
 	return (ISC_R_SUCCESS);
 
@@ -1158,6 +1290,8 @@
 	DESTROYLOCK(&mgr->pool_lock);
  kill_buffer_lock:
 	DESTROYLOCK(&mgr->buffer_lock);
+ kill_arc4_lock:
+	DESTROYLOCK(&mgr->arc4_lock);
  kill_lock:
 	DESTROYLOCK(&mgr->lock);
  deallocate:
@@ -1244,7 +1378,7 @@
 	isc_mempool_setmaxalloc(mgr->bpool, maxbuffers);
 	isc_mempool_associatelock(mgr->bpool, &mgr->pool_lock);
 
-	result = qid_allocate(mgr, buckets, increment, ISC_TRUE, &mgr->qid);
+	result = qid_allocate(mgr, buckets, increment, &mgr->qid);
 	if (result != ISC_R_SUCCESS)
 		goto cleanup;
 
@@ -1283,20 +1417,27 @@
 }
 
 static isc_boolean_t
-blacklisted(dns_dispatchmgr_t *mgr, isc_socket_t *sock) {
+blacklisted(dns_dispatchmgr_t *mgr, isc_socket_t *sock,
+	    isc_sockaddr_t *sockaddrp)
+{
 	isc_sockaddr_t sockaddr;
 	isc_result_t result;
 
+	REQUIRE(sock != NULL || sockaddrp != NULL);
+
 	if (mgr->portlist == NULL)
 		return (ISC_FALSE);
 
-	result = isc_socket_getsockname(sock, &sockaddr);
-	if (result != ISC_R_SUCCESS)
-		return (ISC_FALSE);
+	if (sock != NULL) {
+		sockaddrp = &sockaddr;
+		result = isc_socket_getsockname(sock, sockaddrp);
+		if (result != ISC_R_SUCCESS)
+			return (ISC_FALSE);
+	}
 
 	if (mgr->portlist != NULL &&
-	    dns_portlist_match(mgr->portlist, isc_sockaddr_pf(&sockaddr),
-			       isc_sockaddr_getport(&sockaddr)))
+	    dns_portlist_match(mgr->portlist, isc_sockaddr_pf(sockaddrp),
+			       isc_sockaddr_getport(sockaddrp)))
 		return (ISC_TRUE);
 	return (ISC_FALSE);
 }
@@ -1317,7 +1458,7 @@
 	if (disp->mgr->portlist != NULL &&
 	    isc_sockaddr_getport(addr) == 0 &&
 	    isc_sockaddr_getport(&disp->local) == 0 &&
-	    blacklisted(disp->mgr, disp->socket))
+	    blacklisted(disp->mgr, disp->socket, NULL))
 		return (ISC_FALSE);
 
 	/*
@@ -1390,7 +1531,7 @@
 
 static isc_result_t
 qid_allocate(dns_dispatchmgr_t *mgr, unsigned int buckets,
-	     unsigned int increment, isc_boolean_t usepool, dns_qid_t **qidp)
+	     unsigned int increment, dns_qid_t **qidp)
 {
 	dns_qid_t *qid;
 	unsigned int i;
@@ -1411,16 +1552,8 @@
 		return (ISC_R_NOMEMORY);
 	}
 
-	if (nsid_init(mgr->mctx, &qid->nsid, usepool) != ISC_R_SUCCESS) {
-		isc_mem_put(mgr->mctx, qid->qid_table,
-			    buckets * sizeof(dns_displist_t));
-		isc_mem_put(mgr->mctx, qid, sizeof(*qid));
-		return (ISC_R_NOMEMORY);
-	}
-
 	if (isc_mutex_init(&qid->lock) != ISC_R_SUCCESS) {
 		UNEXPECTED_ERROR(__FILE__, __LINE__, "isc_mutex_init failed");
-		nsid_destroy(mgr->mctx, &qid->nsid);
 		isc_mem_put(mgr->mctx, qid->qid_table,
 			    buckets * sizeof(dns_displist_t));
 		isc_mem_put(mgr->mctx, qid, sizeof(*qid));
@@ -1448,7 +1581,6 @@
 
 	*qidp = NULL;
 	qid->magic = 0;
-	nsid_destroy(mctx, &qid->nsid);
 	isc_mem_put(mctx, qid->qid_table,
 		    qid->qid_nbuckets * sizeof(dns_displist_t));
 	DESTROYLOCK(&qid->lock);
@@ -1485,6 +1617,7 @@
 	disp->refcount = 1;
 	disp->recv_pending = 0;
 	memset(&disp->local, 0, sizeof(disp->local));
+	disp->localport = 0;
 	disp->shutting_down = 0;
 	disp->shutdown_out = 0;
 	disp->connected = 0;
@@ -1592,7 +1725,7 @@
 		return (result);
 	}
 
-	result = qid_allocate(mgr, buckets, increment, ISC_FALSE, &disp->qid);
+	result = qid_allocate(mgr, buckets, increment, &disp->qid);
 	if (result != ISC_R_SUCCESS)
 		goto deallocate_dispatch;
 
@@ -1657,7 +1790,7 @@
 		    dns_dispatch_t **dispp)
 {
 	isc_result_t result;
-	dns_dispatch_t *disp;
+	dns_dispatch_t *disp = NULL;
 
 	REQUIRE(VALID_DISPATCHMGR(mgr));
 	REQUIRE(sockmgr != NULL);
@@ -1677,6 +1810,11 @@
 
 	LOCK(&mgr->lock);
 
+	if ((attributes & DNS_DISPATCHATTR_RANDOMPORT) != 0) {
+		REQUIRE(isc_sockaddr_getport(localaddr) == 0);
+		goto createudp;
+	}
+
 	/*
 	 * First, see if we have a dispatcher that matches.
 	 */
@@ -1705,6 +1843,7 @@
 		return (ISC_R_SUCCESS);
 	}
 
+ createudp:
 	/*
 	 * Nope, create one.
 	 */
@@ -1740,7 +1879,9 @@
 	dns_dispatch_t *disp;
 	isc_socket_t *sock = NULL;
 	isc_socket_t *held[DNS_DISPATCH_HELD];
-	unsigned int i = 0, j = 0;
+	unsigned int i = 0, j = 0, k = 0;
+	isc_sockaddr_t localaddr_bound;
+	in_port_t localport = 0;
 
 	/*
 	 * dispatch_allocate() checks mgr for us.
@@ -1756,11 +1897,34 @@
 	 * from returning the same port to us too quickly.
 	 */
 	memset(held, 0, sizeof(held));
+	localaddr_bound = *localaddr;
  getsocket:
-	result = create_socket(sockmgr, localaddr, &sock);
+	if ((attributes & DNS_DISPATCHATTR_RANDOMPORT) != 0) {
+		in_port_t prt;
+
+		/* XXX: should the range be configurable? */
+		prt = 1024 + dispatch_arc4uniformrandom(mgr, 65535 - 1023);
+		isc_sockaddr_setport(&localaddr_bound, prt);
+		if (blacklisted(mgr, NULL, &localaddr_bound)) {
+			if (++k == 1024)
+				attributes &= ~DNS_DISPATCHATTR_RANDOMPORT;
+			goto getsocket;
+		}
+		result = create_socket(sockmgr, &localaddr_bound, &sock);
+		if (result == ISC_R_ADDRINUSE) {
+			if (++k == 1024)
+				attributes &= ~DNS_DISPATCHATTR_RANDOMPORT;
+			goto getsocket;
+		}
+		localport = prt;
+	} else
+		result = create_socket(sockmgr, localaddr, &sock);
 	if (result != ISC_R_SUCCESS)
 		goto deallocate_dispatch;
-	if (isc_sockaddr_getport(localaddr) == 0 && blacklisted(mgr, sock)) {
+	if ((attributes & DNS_DISPATCHATTR_RANDOMPORT) == 0 &&
+	    isc_sockaddr_getport(localaddr) == 0 &&
+	    blacklisted(mgr, sock, NULL))
+	{
 		if (held[i] != NULL)
 			isc_socket_detach(&held[i]);
 		held[i++] = sock;
@@ -1781,6 +1945,7 @@
 	disp->socktype = isc_sockettype_udp;
 	disp->socket = sock;
 	disp->local = *localaddr;
+	disp->localport = localport;
 
 	disp->task = NULL;
 	result = isc_task_create(taskmgr, 0, &disp->task);
@@ -1911,19 +2076,20 @@
 	/*
 	 * Try somewhat hard to find an unique ID.
 	 */
+	id = (dns_messageid_t)dispatch_arc4random(disp->mgr);
 	qid = DNS_QID(disp);
 	LOCK(&qid->lock);
-	id = dns_randomid(&qid->nsid);
-	bucket = dns_hash(qid, dest, id);
+	bucket = dns_hash(qid, dest, id, disp->localport);
 	ok = ISC_FALSE;
 	for (i = 0; i < 64; i++) {
-		if (bucket_search(qid, dest, id, bucket) == NULL) {
+		if (bucket_search(qid, dest, id, disp->localport, bucket) ==
+		    NULL) {
 			ok = ISC_TRUE;
 			break;
 		}
 		id += qid->qid_increment;
 		id &= 0x0000ffff;
-		bucket = dns_hash(qid, dest, id);
+		bucket = dns_hash(qid, dest, id, disp->localport);
 	}
 
 	if (!ok) {
@@ -1945,6 +2111,7 @@
 	isc_task_attach(task, &res->task);
 	res->disp = disp;
 	res->id = id;
+	res->port = disp->localport;
 	res->bucket = bucket;
 	res->host = *dest;
 	res->action = action;
@@ -2256,409 +2423,3 @@
 	}
 }
 #endif
-
-/*
- * Allow the user to pick one of two ID randomization algorithms.
- *
- * The first algorithm is an adaptation of the sequence shuffling
- * algorithm discovered by Carter Bays and S. D. Durham [ACM Trans. Math.
- * Software 2 (1976), 59-64], as documented as Algorithm B in Chapter
- * 3.2.2 in Volume 2 of Knuth's "The Art of Computer Programming".  We use
- * a randomly selected linear congruential random number generator with a
- * modulus of 2^16, whose increment is a randomly picked odd number, and
- * whose multiplier is picked from a set which meets the following
- * criteria:
- *     Is of the form 8*n+5, which ensures "high potency" according to
- *     principle iii in the summary chapter 3.6.  This form also has a
- *     gcd(a-1,m) of 4 which is good according to principle iv.
- *
- *     Is between 0.01 and 0.99 times the modulus as specified by
- *     principle iv.
- *
- *     Passes the spectral test "with flying colors" (ut >= 1) in
- *     dimensions 2 through 6 as calculated by Algorithm S in Chapter
- *     3.3.4 and the ratings calculated by formula 35 in section E.
- *
- *     Of the multipliers that pass this test, pick the set that is
- *     best according to the theoretical bounds of the serial
- *     correlation test.  This was calculated using a simplified
- *     version of Knuth's Theorem K in Chapter 3.3.3.
- *
- * These criteria may not be important for this use, but we might as well
- * pick from the best generators since there are so many possible ones and
- * we don't have that many random bits to do the picking.
- *
- * We use a modulus of 2^16 instead of something bigger so that we will
- * tend to cycle through all the possible IDs before repeating any,
- * however the shuffling will perturb this somewhat.  Theoretically there
- * is no minimimum interval between two uses of the same ID, but in
- * practice it seems to be >64000.
- *
- * Our adaptatation  of Algorithm B mixes the hash state which has
- * captured various random events into the shuffler to perturb the
- * sequence.
- *
- * One disadvantage of this algorithm is that if the generator parameters
- * were to be guessed, it would be possible to mount a limited brute force
- * attack on the ID space since the IDs are only shuffled within a limited
- * range.
- *
- * The second algorithm uses the same random number generator to populate
- * a pool of 65536 IDs.  The hash state is used to pick an ID from a window
- * of 4096 IDs in this pool, then the chosen ID is swapped with the ID
- * at the beginning of the window and the window position is advanced.
- * This means that the interval between uses of the ID will be no less
- * than 65536-4096.  The ID sequence in the pool will become more random
- * over time.
- *
- * For both algorithms, two more linear congruential random number generators
- * are selected.  The ID from the first part of algorithm is used to seed
- * the first of these generators, and its output is used to seed the second.
- * The strategy is use these generators as 1 to 1 hashes to obfuscate the
- * properties of the generator used in the first part of either algorithm.
- *
- * The first algorithm may be suitable for use in a client resolver since
- * its memory requirements are fairly low and it's pretty random out of
- * the box.  It is somewhat succeptible to a limited brute force attack,
- * so the second algorithm is probably preferable for a longer running
- * program that issues a large number of queries and has time to randomize
- * the pool.
- */
-
-#define NSID_SHUFFLE_TABLE_SIZE 100 /* Suggested by Knuth */
-/*
- * Pick one of the next 4096 IDs in the pool.
- * There is a tradeoff here between randomness and how often and ID is reused.
- */
-#define NSID_LOOKAHEAD 4096     /* Must be a power of 2 */
-#define NSID_SHUFFLE_ONLY 1     /* algorithm 1 */
-#define NSID_USE_POOL 2         /* algorithm 2 */
-#define NSID_HASHSHIFT       3
-#define NSID_HASHROTATE(v) \
-        (((v) << NSID_HASHSHIFT) | ((v) >> ((sizeof(v) * 8) - NSID_HASHSHIFT)))
-
-static isc_uint32_t	nsid_hash_state;
-
-/*
- * Keep a running hash of various bits of data that we'll use to
- * stir the ID pool or perturb the ID generator
- */
-static void
-nsid_hash(void *data, size_t len) {
-	unsigned char *p = data;
-	/*
-	 * Hash function similar to the one we use for hashing names.
-	 * We don't fold case or toss the upper bit here, though.
-	 * This hash doesn't do much interesting when fed binary zeros,
-	 * so there may be a better hash function.
-	 * This function doesn't need to be very strong since we're
-	 * only using it to stir the pool, but it should be reasonably
-	 * fast.
-	 */
-	/*
-	 * We don't care about locking access to nsid_hash_state.
-	 * In fact races make the result even more non deteministic.
-	 */
-	while (len-- > 0U) {
-		nsid_hash_state = NSID_HASHROTATE(nsid_hash_state);
-		nsid_hash_state += *p++;
-	}
-}
-
-/*
- * Table of good linear congruential multipliers for modulus 2^16
- * in order of increasing serial correlation bounds (so trim from
- * the end).
- */
-static const isc_uint16_t nsid_multiplier_table[] = {
-	17565, 25013, 11733, 19877, 23989, 23997, 24997, 25421,
-	26781, 27413, 35901, 35917, 35973, 36229, 38317, 38437,
-	39941, 40493, 41853, 46317, 50581, 51429, 53453, 53805,
-	11317, 11789, 12045, 12413, 14277, 14821, 14917, 18989,
-	19821, 23005, 23533, 23573, 23693, 27549, 27709, 28461,
-	29365, 35605, 37693, 37757, 38309, 41285, 45261, 47061,
-	47269, 48133, 48597, 50277, 50717, 50757, 50805, 51341,
-	51413, 51581, 51597, 53445, 11493, 14229, 20365, 20653,
-	23485, 25541, 27429, 29421, 30173, 35445, 35653, 36789,
-	36797, 37109, 37157, 37669, 38661, 39773, 40397, 41837,
-	41877, 45293, 47277, 47845, 49853, 51085, 51349, 54085,
-	56933,  8877,  8973,  9885, 11365, 11813, 13581, 13589,
-	13613, 14109, 14317, 15765, 15789, 16925, 17069, 17205,
-	17621, 17941, 19077, 19381, 20245, 22845, 23733, 24869,
-	25453, 27213, 28381, 28965, 29245, 29997, 30733, 30901,
-	34877, 35485, 35613, 36133, 36661, 36917, 38597, 40285,
-	40693, 41413, 41541, 41637, 42053, 42349, 45245, 45469,
-	46493, 48205, 48613, 50861, 51861, 52877, 53933, 54397,
-	55669, 56453, 56965, 58021,  7757,  7781,  8333,  9661,
-	12229, 14373, 14453, 17549, 18141, 19085, 20773, 23701,
-	24205, 24333, 25261, 25317, 27181, 30117, 30477, 34757,
-	34885, 35565, 35885, 36541, 37957, 39733, 39813, 41157,
-	41893, 42317, 46621, 48117, 48181, 49525, 55261, 55389,
-	56845,  7045,  7749,  7965,  8469,  9133,  9549,  9789,
-	10173, 11181, 11285, 12253, 13453, 13533, 13757, 14477,
-	15053, 16901, 17213, 17269, 17525, 17629, 18605, 19013,
-	19829, 19933, 20069, 20093, 23261, 23333, 24949, 25309,
-	27613, 28453, 28709, 29301, 29541, 34165, 34413, 37301,
-	37773, 38045, 38405, 41077, 41781, 41925, 42717, 44437,
-	44525, 44613, 45933, 45941, 47077, 50077, 50893, 52117,
-	 5293, 55069, 55989, 58125, 59205,  6869, 14685, 15453,
-	16821, 17045, 17613, 18437, 21029, 22773, 22909, 25445,
-	25757, 26541, 30709, 30909, 31093, 31149, 37069, 37725,
-	37925, 38949, 39637, 39701, 40765, 40861, 42965, 44813,
-	45077, 45733, 47045, 50093, 52861, 52957, 54181, 56325,
-	56365, 56381, 56877, 57013,  5741, 58101, 58669,  8613,
-	10045, 10261, 10653, 10733, 11461, 12261, 14069, 15877,
-	17757, 21165, 23885, 24701, 26429, 26645, 27925, 28765,
-	29197, 30189, 31293, 39781, 39909, 40365, 41229, 41453,
-	41653, 42165, 42365, 47421, 48029, 48085, 52773,  5573,
-	57037, 57637, 58341, 58357, 58901,  6357,  7789,  9093,
-	10125, 10709, 10765, 11957, 12469, 13437, 13509, 14773,
-	15437, 15773, 17813, 18829, 19565, 20237, 23461, 23685,
-	23725, 23941, 24877, 25461, 26405, 29509, 30285, 35181,
-	37229, 37893, 38565, 40293, 44189, 44581, 45701, 47381,
-	47589, 48557,  4941, 51069,  5165, 52797, 53149,  5341,
-	56301, 56765, 58581, 59493, 59677,  6085,  6349,  8293,
-	 8501,  8517, 11597, 11709, 12589, 12693, 13517, 14909,
-	17397, 18085, 21101, 21269, 22717, 25237, 25661, 29189,
-	30101, 31397, 33933, 34213, 34661, 35533, 36493, 37309,
-	40037,  4189, 42909, 44309, 44357, 44389,  4541, 45461,
-	46445, 48237, 54149, 55301, 55853, 56621, 56717, 56901,
-	 5813, 58437, 12493, 15365, 15989, 17829, 18229, 19341,
-	21013, 21357, 22925, 24885, 26053, 27581, 28221, 28485,
-	30605, 30613, 30789, 35437, 36285, 37189,  3941, 41797,
-	 4269, 42901, 43293, 44645, 45221, 46893,  4893, 50301,
-	50325,  5189, 52109, 53517, 54053, 54485,  5525, 55949,
-	56973, 59069, 59421, 60733, 61253,  6421,  6701,  6709,
-	 7101,  8669, 15797, 19221, 19837, 20133, 20957, 21293,
-	21461, 22461, 29085, 29861, 30869, 34973, 36469, 37565,
-	38125, 38829, 39469, 40061, 40117, 44093, 47429, 48341,
-	50597, 51757,  5541, 57629, 58405, 59621, 59693, 59701,
-	61837,  7061, 10421, 11949, 15405, 20861, 25397, 25509,
-	25893, 26037, 28629, 28869, 29605, 30213, 34205, 35637,
-	36365, 37285,  3773, 39117,  4021, 41061, 42653, 44509,
-	 4461, 44829,  4725,  5125, 52269, 56469, 59085,  5917,
-	60973,  8349, 17725, 18637, 19773, 20293, 21453, 22533,
-	24285, 26333, 26997, 31501, 34541, 34805, 37509, 38477,
-	41333, 44125, 46285, 46997, 47637, 48173,  4925, 50253,
-	50381, 50917, 51205, 51325, 52165, 52229,  5253,  5269,
-	53509, 56253, 56341,  5821, 58373, 60301, 61653, 61973,
-	62373,  8397, 11981, 14341, 14509, 15077, 22261, 22429,
-	24261, 28165, 28685, 30661, 34021, 34445, 39149,  3917,
-	43013, 43317, 44053, 44101,  4533, 49541, 49981,  5277,
-	54477, 56357, 57261, 57765, 58573, 59061, 60197, 61197,
-	62189,  7725,  8477,  9565, 10229, 11437, 14613, 14709,
-	16813, 20029, 20677, 31445,  3165, 31957,  3229, 33541,
-	36645,  3805, 38973,  3965,  4029, 44293, 44557, 46245,
-	48917,  4909, 51749, 53709, 55733, 56445,  5925,  6093,
-	61053, 62637,  8661,  9109, 10821, 11389, 13813, 14325,
-	15501, 16149, 18845, 22669, 26437, 29869, 31837, 33709,
-	33973, 34173,  3677,  3877,  3981, 39885, 42117,  4421,
-	44221, 44245, 44693, 46157, 47309,  5005, 51461, 52037,
-	55333, 55693, 56277, 58949,  6205, 62141, 62469,  6293,
-	10101, 12509, 14029, 17997, 20469, 21149, 25221, 27109,
-	 2773,  2877, 29405, 31493, 31645,  4077, 42005, 42077,
-	42469, 42501, 44013, 48653, 49349,  4997, 50101, 55405,
-	56957, 58037, 59429, 60749, 61797, 62381, 62837,  6605,
-	10541, 23981, 24533,  2701, 27333, 27341, 31197, 33805,
-	 3621, 37381,  3749,  3829, 38533, 42613, 44381, 45901,
-	48517, 51269, 57725, 59461, 60045, 62029, 13805, 14013,
-	15461, 16069, 16157, 18573,  2309, 23501, 28645,  3077,
-	31541, 36357, 36877,  3789, 39429, 39805, 47685, 47949,
-	49413,  5485, 56757, 57549, 57805, 58317, 59549, 62213,
-	62613, 62853, 62933,  8909, 12941, 16677, 20333, 21541,
-	24429, 26077, 26421,  2885, 31269, 33381,  3661, 40925,
-	42925, 45173,  4525,  4709, 53133, 55941, 57413, 57797,
-	62125, 62237, 62733,  6773, 12317, 13197, 16533, 16933,
-	18245,  2213,  2477, 29757, 33293, 35517, 40133, 40749,
-	 4661, 49941, 62757,  7853,  8149,  8573, 11029, 13421,
-	21549, 22709, 22725, 24629,  2469, 26125,  2669, 34253,
-	36709, 41013, 45597, 46637, 52285, 52333, 54685, 59013,
-	60997, 61189, 61981, 62605, 62821,  7077,  7525,  8781,
-	10861, 15277,  2205, 22077, 28517, 28949, 32109, 33493,
-	 4661, 49941, 62757,  7853,  8149,  8573, 11029, 13421,
-	21549, 22709, 22725, 24629,  2469, 26125,  2669, 34253,
-	36709, 41013, 45597, 46637, 52285, 52333, 54685, 59013,
-	60997, 61189, 61981, 62605, 62821,  7077,  7525,  8781,
-	10861, 15277,  2205, 22077, 28517, 28949, 32109, 33493,
-	 3685, 39197, 39869, 42621, 44997, 48565,  5221, 57381,
-	61749, 62317, 63245, 63381, 23149,  2549, 28661, 31653,
-	33885, 36341, 37053, 39517, 42805, 45853, 48997, 59349,
-	60053, 62509, 63069,  6525,  1893, 20181,  2365, 24893,
-	27397, 31357, 32277, 33357, 34437, 36677, 37661, 43469,
-	43917, 50997, 53869,  5653, 13221, 16741, 17893,  2157,
-	28653, 31789, 35301, 35821, 61613, 62245, 12405, 14517,
-	17453, 18421,  3149,  3205, 40341,  4109, 43941, 46869,
-	48837, 50621, 57405, 60509, 62877,  8157, 12933, 12957,
-	16501, 19533,  3461, 36829, 52357, 58189, 58293, 63053,
-	17109,  1933, 32157, 37701, 59005, 61621, 13029, 15085,
-	16493, 32317, 35093,  5061, 51557, 62221, 20765, 24613,
-	 2629, 30861, 33197, 33749, 35365, 37933, 40317, 48045,
-	56229, 61157, 63797,  7917, 17965,  1917,  1973, 20301,
-	 2253, 33157, 58629, 59861, 61085, 63909,  8141,  9221,
-	14757,  1581, 21637, 26557, 33869, 34285, 35733, 40933,
-	42517, 43501, 53653, 61885, 63805,  7141, 21653, 54973,
-	31189, 60061, 60341, 63357, 16045,  2053, 26069, 33997,
-	43901, 54565, 63837,  8949, 17909, 18693, 32349, 33125,
-	37293, 48821, 49053, 51309, 64037,  7117,  1445, 20405,
-	23085, 26269, 26293, 27349, 32381, 33141, 34525, 36461,
-	37581, 43525,  4357, 43877,  5069, 55197, 63965,  9845,
-	12093,  2197,  2229, 32165, 33469, 40981, 42397,  8749,
-	10853,  1453, 18069, 21693, 30573, 36261, 37421, 42533
-};
-
-#define NSID_MULT_TABLE_SIZE \
-        ((sizeof nsid_multiplier_table)/(sizeof nsid_multiplier_table[0]))
-#define NSID_RANGE_MASK (NSID_LOOKAHEAD - 1)
-#define NSID_POOL_MASK 0xFFFF /* used to wrap the pool index */
-#define NSID_SHUFFLE_ONLY 1
-#define NSID_USE_POOL 2
-
-static isc_uint16_t
-nsid_next(dns_nsid_t *nsid) {
-        isc_uint16_t id, compressed_hash;
-	isc_uint16_t j;
-
-        compressed_hash = ((nsid_hash_state >> 16) ^
-			   (nsid_hash_state)) & 0xFFFF;
-
-	if (nsid->nsid_usepool) {
-	        isc_uint16_t pick;
-
-                pick = compressed_hash & NSID_RANGE_MASK;
-		pick = (nsid->nsid_state + pick) & NSID_POOL_MASK;
-                id = nsid->nsid_pool[pick];
-                if (pick != 0) {
-                        /* Swap two IDs to stir the pool */
-                        nsid->nsid_pool[pick] =
-                                nsid->nsid_pool[nsid->nsid_state];
-                        nsid->nsid_pool[nsid->nsid_state] = id;
-                }
-
-                /* increment the base pointer into the pool */
-                if (nsid->nsid_state == 65535)
-                        nsid->nsid_state = 0;
-                else
-                        nsid->nsid_state++;
-	} else {
-		/*
-		 * This is the original Algorithm B
-		 * j = ((u_long) NSID_SHUFFLE_TABLE_SIZE * nsid_state2) >> 16;
-		 *
-		 * We'll perturb it with some random stuff  ...
-		 */
-		j = ((isc_uint32_t) NSID_SHUFFLE_TABLE_SIZE *
-		     (nsid->nsid_state2 ^ compressed_hash)) >> 16;
-		nsid->nsid_state2 = id = nsid->nsid_vtable[j];
-		nsid->nsid_state = (((isc_uint32_t) nsid->nsid_a1 * nsid->nsid_state) +
-				      nsid->nsid_c1) & 0xFFFF;
-		nsid->nsid_vtable[j] = nsid->nsid_state;
-	}
-
-        /* Now lets obfuscate ... */
-        id = (((isc_uint32_t) nsid->nsid_a2 * id) + nsid->nsid_c2) & 0xFFFF;
-        id = (((isc_uint32_t) nsid->nsid_a3 * id) + nsid->nsid_c3) & 0xFFFF;
-
-        return (id);
-}
-
-static isc_result_t
-nsid_init(isc_mem_t *mctx, dns_nsid_t *nsid, isc_boolean_t usepool) {
-        isc_time_t now;
-        pid_t mypid;
-        isc_uint16_t a1ndx, a2ndx, a3ndx, c1ndx, c2ndx, c3ndx;
-        int i;
-
-	isc_time_now(&now);
-        mypid = getpid();
-
-        /* Initialize the state */
-	memset(nsid, 0, sizeof(*nsid));
-        nsid_hash(&now, sizeof now);
-        nsid_hash(&mypid, sizeof mypid);
-
-        /*
-         * Select our random number generators and initial seed.
-         * We could really use more random bits at this point,
-         * but we'll try to make a silk purse out of a sows ear ...
-         */
-        /* generator 1 */
-        a1ndx = ((isc_uint32_t) NSID_MULT_TABLE_SIZE *
-                 (nsid_hash_state & 0xFFFF)) >> 16;
-        nsid->nsid_a1 = nsid_multiplier_table[a1ndx];
-        c1ndx = (nsid_hash_state >> 9) & 0x7FFF;
-        nsid->nsid_c1 = 2 * c1ndx + 1;
-
-        /* generator 2, distinct from 1 */
-        a2ndx = ((isc_uint32_t) (NSID_MULT_TABLE_SIZE - 1) *
-                 ((nsid_hash_state >> 10) & 0xFFFF)) >> 16;
-        if (a2ndx >= a1ndx)
-                a2ndx++;
-        nsid->nsid_a2 = nsid_multiplier_table[a2ndx];
-        c2ndx = nsid_hash_state % 32767;
-        if (c2ndx >= c1ndx)
-                c2ndx++;
-        nsid->nsid_c2 = 2*c2ndx + 1;
-
-        /* generator 3, distinct from 1 and 2 */
-        a3ndx = ((isc_uint32_t) (NSID_MULT_TABLE_SIZE - 2) *
-                 ((nsid_hash_state >> 20) & 0xFFFF)) >> 16;
-        if (a3ndx >= a1ndx || a3ndx >= a2ndx)
-                a3ndx++;
-        if (a3ndx >= a1ndx && a3ndx >= a2ndx)
-                a3ndx++;
-        nsid->nsid_a3 = nsid_multiplier_table[a3ndx];
-        c3ndx = nsid_hash_state % 32766;
-        if (c3ndx >= c1ndx || c3ndx >= c2ndx)
-                c3ndx++;
-        if (c3ndx >= c1ndx && c3ndx >= c2ndx)
-                c3ndx++;
-        nsid->nsid_c3 = 2*c3ndx + 1;
-
-        nsid->nsid_state =
-		((nsid_hash_state >> 16) ^ (nsid_hash_state)) & 0xFFFF;
-
-	nsid->nsid_usepool = usepool;
-	if (nsid->nsid_usepool) {
-                nsid->nsid_pool = isc_mem_get(mctx, 0x10000 * sizeof(isc_uint16_t));
-		if (nsid->nsid_pool == NULL)
-			return (ISC_R_NOMEMORY);
-                for (i = 0; ; i++) {
-                        nsid->nsid_pool[i] = nsid->nsid_state;
-                        nsid->nsid_state =
-				 (((u_long) nsid->nsid_a1 * nsid->nsid_state) +
-				   nsid->nsid_c1) & 0xFFFF;
-                        if (i == 0xFFFF)
-                                break;
-                }
-	} else {
-		nsid->nsid_vtable = isc_mem_get(mctx, NSID_SHUFFLE_TABLE_SIZE *
-						(sizeof(isc_uint16_t)) );
-		if (nsid->nsid_vtable == NULL)
-			return (ISC_R_NOMEMORY);
-
-		for (i = 0; i < NSID_SHUFFLE_TABLE_SIZE; i++) {
-			nsid->nsid_vtable[i] = nsid->nsid_state;
-			nsid->nsid_state =
-				   (((isc_uint32_t) nsid->nsid_a1 * nsid->nsid_state) +
-					 nsid->nsid_c1) & 0xFFFF;
-		}
-		nsid->nsid_state2 = nsid->nsid_state;
-	} 
-	return (ISC_R_SUCCESS);
-}
-
-static void
-nsid_destroy(isc_mem_t *mctx, dns_nsid_t *nsid) {
-	if (nsid->nsid_usepool)
-		isc_mem_put(mctx, nsid->nsid_pool,
-			    0x10000 * sizeof(isc_uint16_t));
-	else
-		isc_mem_put(mctx, nsid->nsid_vtable,
-			    NSID_SHUFFLE_TABLE_SIZE * (sizeof(isc_uint16_t)) );
-	memset(nsid, 0, sizeof(*nsid));
-}
-
-void
-dns_dispatch_hash(void *data, size_t len) {
-	nsid_hash(data, len);
-}
diff --exclude=CVS -r -u 6.3-release/src/contrib/bind9/lib/dns/include/dns/dispatch.h 6.3-patched/src/contrib/bind9/lib/dns/include/dns/dispatch.h
--- 6.3-release/src/contrib/bind9/lib/dns/include/dns/dispatch.h	Wed Jul 25 02:23:07 2007
+++ 6.3-patched/src/contrib/bind9/lib/dns/include/dns/dispatch.h	Tue Aug 19 12:11:54 2008
@@ -112,6 +112,9 @@
  * _MAKEQUERY
  *	The dispatcher can be used to issue queries to other servers, and
  *	accept replies from them.
+ *
+ * _RANDOMPORT
+ *	Allocate UDP port randomly.
  */
 #define DNS_DISPATCHATTR_PRIVATE	0x00000001U
 #define DNS_DISPATCHATTR_TCP		0x00000002U
@@ -121,6 +124,7 @@
 #define DNS_DISPATCHATTR_NOLISTEN	0x00000020U
 #define DNS_DISPATCHATTR_MAKEQUERY	0x00000040U
 #define DNS_DISPATCHATTR_CONNECTED	0x00000080U
+#define DNS_DISPATCHATTR_RANDOMPORT	0x00000100U
 
 isc_result_t
 dns_dispatchmgr_create(isc_mem_t *mctx, isc_entropy_t *entropy,
@@ -435,13 +439,6 @@
  * Requires:
  * 	disp is valid, and the attribute DNS_DISPATCHATTR_NOLISTEN is set.
  * 	event != NULL
- */
-
-void
-dns_dispatch_hash(void *data, size_t len);
-/*%<
- * Feed 'data' to the dispatch query id generator where 'len' is the size
- * of 'data'.
  */
 
 ISC_LANG_ENDDECLS
diff --exclude=CVS -r -u 6.3-release/src/contrib/bind9/lib/dns/resolver.c 6.3-patched/src/contrib/bind9/lib/dns/resolver.c
--- 6.3-release/src/contrib/bind9/lib/dns/resolver.c	Tue Feb  6 17:42:08 2007
+++ 6.3-patched/src/contrib/bind9/lib/dns/resolver.c	Tue Aug 19 12:11:54 2008
@@ -1054,17 +1054,50 @@
 		 * A dispatch will be created once the connect succeeds.
 		 */
 	} else {
+		isc_sockaddr_t localaddr;
+		unsigned int attrs, attrmask;
+		dns_dispatch_t *disp_base;
+
+		attrs = 0;
+		attrs |= DNS_DISPATCHATTR_UDP;
+		attrs |= DNS_DISPATCHATTR_RANDOMPORT;
+
+		attrmask = 0;
+		attrmask |= DNS_DISPATCHATTR_UDP;
+		attrmask |= DNS_DISPATCHATTR_TCP;
+		attrmask |= DNS_DISPATCHATTR_IPV4;
+		attrmask |= DNS_DISPATCHATTR_IPV6;
+
 		switch (isc_sockaddr_pf(&addrinfo->sockaddr)) {
-		case PF_INET:
-			dns_dispatch_attach(res->dispatchv4, &query->dispatch);
+		case AF_INET:
+			disp_base = res->dispatchv4;
+			attrs |= DNS_DISPATCHATTR_IPV4;
 			break;
-		case PF_INET6:
-			dns_dispatch_attach(res->dispatchv6, &query->dispatch);
+		case AF_INET6:
+			disp_base = res->dispatchv6;
+			attrs |= DNS_DISPATCHATTR_IPV6;
 			break;
 		default:
 			result = ISC_R_NOTIMPLEMENTED;
 			goto cleanup_query;
 		}
+
+		result = dns_dispatch_getlocaladdress(disp_base, &localaddr);
+		if (result != ISC_R_SUCCESS)
+			goto cleanup_query;
+		if (isc_sockaddr_getport(&localaddr) == 0) {
+			result = dns_dispatch_getudp(res->dispatchmgr,
+						     res->socketmgr,
+						     res->taskmgr,
+						     &localaddr,
+						     4096, 1000, 32768,
+						     16411, 16433,
+						     attrs, attrmask,
+						     &query->dispatch);
+			if (result != ISC_R_SUCCESS)
+				goto cleanup_query;
+		} else
+			dns_dispatch_attach(disp_base, &query->dispatch);
 		/*
 		 * We should always have a valid dispatcher here.  If we
 		 * don't support a protocol family, then its dispatcher
diff --exclude=CVS -r -u 6.3-release/src/crypto/openssh/channels.c 6.3-patched/src/crypto/openssh/channels.c
--- 6.3-release/src/crypto/openssh/channels.c	Fri Oct  6 08:07:12 2006
+++ 6.3-patched/src/crypto/openssh/channels.c	Tue Aug 19 12:13:55 2008
@@ -2895,9 +2895,6 @@
 				debug2("bind port %d: %.100s", port, strerror(errno));
 				close(sock);
 
-				if (ai->ai_next)
-					continue;
-
 				for (n = 0; n < num_socks; n++) {
 					close(socks[n]);
 				}
diff --exclude=CVS -r -u 6.3-release/src/lib/libpthread/sys/lock.c 6.3-patched/src/lib/libpthread/sys/lock.c
--- 6.3-release/src/lib/libpthread/sys/lock.c	Fri Aug  5 13:43:56 2005
+++ 6.3-patched/src/lib/libpthread/sys/lock.c	Tue Aug 19 12:15:38 2008
@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $FreeBSD: src/lib/libpthread/sys/lock.c,v 1.9.2.1 2005/08/05 19:43:56 jhb Exp $
+ * $FreeBSD: src/lib/libpthread/sys/lock.c,v 1.9.2.1.8.2 2008/04/17 00:02:19 cperciva Exp $
  */
 
 #include <sys/types.h>
@@ -117,14 +117,23 @@
 {
 	if (lu == NULL)
 		return (-1);
-	/*
-	 * All lockusers keep their watch request and drop their
-	 * own (lu_myreq) request.  Their own request is either
-	 * some other lockuser's watch request or is the head of
-	 * the lock.
-	 */
-	lu->lu_myreq = lu->lu_watchreq;
-	if (lu->lu_myreq == NULL)
+
+	if (lu->lu_watchreq != NULL) {
+		/*
+		 * In this case the lock is active.  All lockusers
+		 * keep their watch request and drop their own
+		 * (lu_myreq) request.  Their own request is either
+		 * some other lockuser's watch request or is the
+		 * head of the lock.
+		 */
+		lu->lu_myreq = lu->lu_watchreq;
+		lu->lu_watchreq = NULL;
+       }
+       if (lu->lu_myreq == NULL)
+		/*
+		 * Oops, something isn't quite right.  Try to
+		 * allocate one.
+		 */
 		return (_lockuser_init(lu, priv));
 	else {
 		lu->lu_myreq->lr_locked = 1;
diff --exclude=CVS -r -u 6.3-release/src/lib/libpthread/thread/thr_kern.c 6.3-patched/src/lib/libpthread/thread/thr_kern.c
--- 6.3-release/src/lib/libpthread/thread/thr_kern.c	Thu Mar 16 16:29:07 2006
+++ 6.3-patched/src/lib/libpthread/thread/thr_kern.c	Tue Aug 19 12:15:39 2008
@@ -33,7 +33,7 @@
  *
  */
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libpthread/thread/thr_kern.c,v 1.116.2.1 2006/03/16 23:29:07 deischen Exp $");
+__FBSDID("$FreeBSD: src/lib/libpthread/thread/thr_kern.c,v 1.116.2.1.6.2 2008/04/17 00:02:20 cperciva Exp $");
 
 #include <sys/types.h>
 #include <sys/kse.h>
@@ -345,6 +345,17 @@
 		_LCK_SET_PRIVATE2(&curthread->kse->k_lockusers[i], NULL);
 	}
 	curthread->kse->k_locklevel = 0;
+
+	/*
+	 * Reinitialize the thread and signal locks so that
+	 * sigaction() will work after a fork().
+	 */
+	_lock_reinit(&curthread->lock, LCK_ADAPTIVE, _thr_lock_wait,
+	    _thr_lock_wakeup);
+	_lock_reinit(&_thread_signal_lock, LCK_ADAPTIVE, _kse_lock_wait,
+	    _kse_lock_wakeup);
+
+ 
 	_thr_spinlock_init();
 	if (__isthreaded) {
 		_thr_rtld_fini();
@@ -353,6 +364,20 @@
 	__isthreaded = 0;
 	curthread->kse->k_kcb->kcb_kmbx.km_curthread = NULL;
 	curthread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
+
+	/*
+	 * After a fork, it is possible that an upcall occurs in
+	 * the parent KSE that fork()'d before the child process
+	 * is fully created and before its vm space is copied.
+	 * During the upcall, the tcb is set to null or to another
+	 * thread, and this is what gets copied in the child process
+	 * when the vm space is cloned sometime after the upcall
+	 * occurs.  Note that we shouldn't have to set the kcb, but
+	 * we do it for completeness.
+	 */
+	_kcb_set(curthread->kse->k_kcb);
+	_tcb_set(curthread->kse->k_kcb, curthread->tcb);
+ 
 
 	/* After a fork(), there child should have no pending signals. */
 	sigemptyset(&curthread->sigpend);
diff --exclude=CVS -r -u 6.3-release/src/sys/conf/newvers.sh 6.3-patched/src/sys/conf/newvers.sh
--- 6.3-release/src/sys/conf/newvers.sh	Tue Jan 15 16:00:36 2008
+++ 6.3-patched/src/sys/conf/newvers.sh	Tue Aug 19 12:17:45 2008
@@ -28,15 +28,15 @@
 # SUCH DAMAGE.
 #
 #	@(#)newvers.sh	8.1 (Berkeley) 4/20/94
-# $FreeBSD: src/sys/conf/newvers.sh,v 1.69.2.15.2.3 2008/01/15 15:46:21 kensmith Exp $
+# $FreeBSD: src/sys/conf/newvers.sh,v 1.69.2.15.2.7 2008/07/13 18:42:38 cperciva Exp $
 
 TYPE="FreeBSD"
 REVISION="6.3"
-BRANCH="RELEASE"
+BRANCH="RELEASE-p3"
 if [ "X${BRANCH_OVERRIDE}" != "X" ]; then
 	BRANCH=${BRANCH_OVERRIDE}
 fi
-RELEASE=6.3-RELEASE
+RELEASE="${REVISION}-${BRANCH}"
 VERSION="${TYPE} ${RELEASE}"
 
 if [ "X${PARAMFILE}" != "X" ]; then
diff --exclude=CVS -r -u 6.3-release/src/sys/kern/kern_descrip.c 6.3-patched/src/sys/kern/kern_descrip.c
--- 6.3-release/src/sys/kern/kern_descrip.c	Sun Jul  8 02:44:48 2007
+++ 6.3-patched/src/sys/kern/kern_descrip.c	Tue Aug 19 12:20:25 2008
@@ -35,7 +35,7 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/sys/kern/kern_descrip.c,v 1.279.2.15 2007/07/08 08:44:48 netchild Exp $");
+__FBSDID("$FreeBSD: src/sys/kern/kern_descrip.c,v 1.279.2.15.2.1 2008/02/14 11:46:40 simon Exp $");
 
 #include "opt_compat.h"
 #include "opt_ddb.h"
@@ -2022,7 +2022,7 @@
 	int error;
 
 	*vpp = NULL;
-	if ((error = _fget(td, fd, &fp, 0, 0)) != 0)
+	if ((error = _fget(td, fd, &fp, flags, 0)) != 0)
 		return (error);
 	if (fp->f_vnode == NULL) {
 		error = EINVAL;
diff --exclude=CVS -r -u 6.3-release/src/sys/kern/uipc_syscalls.c 6.3-patched/src/sys/kern/uipc_syscalls.c
--- 6.3-release/src/sys/kern/uipc_syscalls.c	Wed Sep 13 03:10:01 2006
+++ 6.3-patched/src/sys/kern/uipc_syscalls.c	Tue Aug 19 12:20:26 2008
@@ -33,7 +33,7 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/sys/kern/uipc_syscalls.c,v 1.221.2.4 2006/09/13 09:10:01 gnn Exp $");
+__FBSDID("$FreeBSD: src/sys/kern/uipc_syscalls.c,v 1.221.2.4.4.1 2008/02/14 11:46:40 simon Exp $");
 
 #include "opt_compat.h"
 #include "opt_ktrace.h"
@@ -1818,20 +1818,23 @@
 		goto done;
 	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
-	obj = vp->v_object;
-	if (obj != NULL) {
-		/*
-		 * Temporarily increase the backing VM object's reference
-		 * count so that a forced reclamation of its vnode does not
-		 * immediately destroy it.
-		 */
-		VM_OBJECT_LOCK(obj);
-		if ((obj->flags & OBJ_DEAD) == 0) {
-			vm_object_reference_locked(obj);
-			VM_OBJECT_UNLOCK(obj);
-		} else {
-			VM_OBJECT_UNLOCK(obj);
-			obj = NULL;
+	if (vp->v_type == VREG) {
+		obj = vp->v_object;
+		if (obj != NULL) {
+			/*
+			 * Temporarily increase the backing VM
+			 * object's reference count so that a forced
+			 * reclamation of its vnode does not
+			 * immediately destroy it.
+			 */
+			VM_OBJECT_LOCK(obj);
+			if ((obj->flags & OBJ_DEAD) == 0) {
+				vm_object_reference_locked(obj);
+				VM_OBJECT_UNLOCK(obj);
+			} else {
+				VM_OBJECT_UNLOCK(obj);
+				obj = NULL;
+			}
 		}
 	}
 	VOP_UNLOCK(vp, 0, td);