1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if 0
33 #ifndef lint
34 static const char sccsid[] = "@(#)pass1.c	8.6 (Berkeley) 4/28/95";
35 #endif /* not lint */
36 #endif
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD: stable/12/sbin/fsck_ffs/pass1.c 369829 2021-05-18 20:26:34Z mckusick $");
39 
40 #include <sys/param.h>
41 #include <sys/stat.h>
42 #include <sys/sysctl.h>
43 
44 #include <ufs/ufs/dinode.h>
45 #include <ufs/ufs/dir.h>
46 #include <ufs/ffs/fs.h>
47 
48 #include <err.h>
49 #include <limits.h>
50 #include <stdint.h>
51 #include <string.h>
52 
53 #include "fsck.h"
54 
55 static ufs2_daddr_t badblk;
56 static ufs2_daddr_t dupblk;
57 static ino_t lastino;		/* last inode in use */
58 
59 static int checkinode(ino_t inumber, struct inodesc *, int rebuildcg);
60 
61 void
pass1(void)62 pass1(void)
63 {
64 	struct inostat *info;
65 	struct inodesc idesc;
66 	struct bufarea *cgbp;
67 	struct cg *cgp;
68 	ino_t inumber, inosused, mininos;
69 	ufs2_daddr_t i, cgd;
70 	u_int8_t *cp;
71 	int c, rebuildcg;
72 
73 	badblk = dupblk = lastino = 0;
74 
75 	/*
76 	 * Set file system reserved blocks in used block map.
77 	 */
78 	for (c = 0; c < sblock.fs_ncg; c++) {
79 		cgd = cgdmin(&sblock, c);
80 		if (c == 0) {
81 			i = cgbase(&sblock, c);
82 		} else
83 			i = cgsblock(&sblock, c);
84 		for (; i < cgd; i++)
85 			setbmap(i);
86 	}
87 	i = sblock.fs_csaddr;
88 	cgd = i + howmany(sblock.fs_cssize, sblock.fs_fsize);
89 	for (; i < cgd; i++)
90 		setbmap(i);
91 
92 	/*
93 	 * Find all allocated blocks.
94 	 */
95 	memset(&idesc, 0, sizeof(struct inodesc));
96 	idesc.id_func = pass1check;
97 	n_files = n_blks = 0;
98 	for (c = 0; c < sblock.fs_ncg; c++) {
99 		inumber = c * sblock.fs_ipg;
100 		setinodebuf(inumber);
101 		cgbp = cglookup(c);
102 		cgp = cgbp->b_un.b_cg;
103 		rebuildcg = 0;
104 		if (!check_cgmagic(c, cgbp))
105 			rebuildcg = 1;
106 		if (!rebuildcg && sblock.fs_magic == FS_UFS2_MAGIC) {
107 			inosused = cgp->cg_initediblk;
108 			if (inosused > sblock.fs_ipg) {
109 				pfatal(
110 "Too many initialized inodes (%ju > %d) in cylinder group %d\nReset to %d\n",
111 				    (uintmax_t)inosused,
112 				    sblock.fs_ipg, c, sblock.fs_ipg);
113 				inosused = sblock.fs_ipg;
114 			}
115 		} else {
116 			inosused = sblock.fs_ipg;
117 		}
118 		if (got_siginfo) {
119 			printf("%s: phase 1: cyl group %d of %d (%d%%)\n",
120 			    cdevname, c, sblock.fs_ncg,
121 			    c * 100 / sblock.fs_ncg);
122 			got_siginfo = 0;
123 		}
124 		if (got_sigalarm) {
125 			setproctitle("%s p1 %d%%", cdevname,
126 			     c * 100 / sblock.fs_ncg);
127 			got_sigalarm = 0;
128 		}
129 		/*
130 		 * If we are using soft updates, then we can trust the
131 		 * cylinder group inode allocation maps to tell us which
132 		 * inodes are allocated. We will scan the used inode map
133 		 * to find the inodes that are really in use, and then
134 		 * read only those inodes in from disk.
135 		 */
136 		if ((preen || inoopt) && usedsoftdep && !rebuildcg) {
137 			cp = &cg_inosused(cgp)[(inosused - 1) / CHAR_BIT];
138 			for ( ; inosused != 0; cp--) {
139 				if (*cp == 0) {
140 					if (inosused > CHAR_BIT)
141 						inosused -= CHAR_BIT;
142 					else
143 						inosused = 0;
144 					continue;
145 				}
146 				for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
147 					if (*cp & i)
148 						break;
149 					inosused--;
150 				}
151 				break;
152 			}
153 		}
154 		/*
155 		 * Allocate inoinfo structures for the allocated inodes.
156 		 */
157 		inostathead[c].il_numalloced = inosused;
158 		if (inosused == 0) {
159 			inostathead[c].il_stat = NULL;
160 			continue;
161 		}
162 		info = Calloc((unsigned)inosused, sizeof(struct inostat));
163 		if (info == NULL)
164 			errx(EEXIT, "cannot alloc %u bytes for inoinfo",
165 			    (unsigned)(sizeof(struct inostat) * inosused));
166 		inostathead[c].il_stat = info;
167 		/*
168 		 * Scan the allocated inodes.
169 		 */
170 		for (i = 0; i < inosused; i++, inumber++) {
171 			if (inumber < UFS_ROOTINO) {
172 				(void)getnextinode(inumber, rebuildcg);
173 				continue;
174 			}
175 			/*
176 			 * NULL return indicates probable end of allocated
177 			 * inodes during cylinder group rebuild attempt.
178 			 * We always keep trying until we get to the minimum
179 			 * valid number for this cylinder group.
180 			 */
181 			if (checkinode(inumber, &idesc, rebuildcg) == 0 &&
182 			    i > cgp->cg_initediblk)
183 				break;
184 		}
185 		/*
186 		 * This optimization speeds up future runs of fsck
187 		 * by trimming down the number of inodes in cylinder
188 		 * groups that formerly had many inodes but now have
189 		 * fewer in use.
190 		 */
191 		mininos = roundup(inosused + INOPB(&sblock), INOPB(&sblock));
192 		if (inoopt && !preen && !rebuildcg &&
193 		    sblock.fs_magic == FS_UFS2_MAGIC &&
194 		    cgp->cg_initediblk > 2 * INOPB(&sblock) &&
195 		    mininos < cgp->cg_initediblk) {
196 			i = cgp->cg_initediblk;
197 			if (mininos < 2 * INOPB(&sblock))
198 				cgp->cg_initediblk = 2 * INOPB(&sblock);
199 			else
200 				cgp->cg_initediblk = mininos;
201 			pwarn("CYLINDER GROUP %d: RESET FROM %ju TO %d %s\n",
202 			    c, i, cgp->cg_initediblk, "VALID INODES");
203 			dirty(cgbp);
204 		}
205 		if (inosused < sblock.fs_ipg)
206 			continue;
207 		lastino += 1;
208 		if (lastino < (c * sblock.fs_ipg))
209 			inosused = 0;
210 		else
211 			inosused = lastino - (c * sblock.fs_ipg);
212 		if (rebuildcg && inosused > cgp->cg_initediblk &&
213 		    sblock.fs_magic == FS_UFS2_MAGIC) {
214 			cgp->cg_initediblk = roundup(inosused, INOPB(&sblock));
215 			pwarn("CYLINDER GROUP %d: FOUND %d VALID INODES\n", c,
216 			    cgp->cg_initediblk);
217 		}
218 		/*
219 		 * If we were not able to determine in advance which inodes
220 		 * were in use, then reduce the size of the inoinfo structure
221 		 * to the size necessary to describe the inodes that we
222 		 * really found.
223 		 */
224 		if (inumber == lastino)
225 			continue;
226 		inostathead[c].il_numalloced = inosused;
227 		if (inosused == 0) {
228 			free(inostathead[c].il_stat);
229 			inostathead[c].il_stat = NULL;
230 			continue;
231 		}
232 		info = Calloc((unsigned)inosused, sizeof(struct inostat));
233 		if (info == NULL)
234 			errx(EEXIT, "cannot alloc %u bytes for inoinfo",
235 			    (unsigned)(sizeof(struct inostat) * inosused));
236 		memmove(info, inostathead[c].il_stat, inosused * sizeof(*info));
237 		free(inostathead[c].il_stat);
238 		inostathead[c].il_stat = info;
239 	}
240 	freeinodebuf();
241 }
242 
243 static int
checkinode(ino_t inumber,struct inodesc * idesc,int rebuildcg)244 checkinode(ino_t inumber, struct inodesc *idesc, int rebuildcg)
245 {
246 	union dinode *dp;
247 	off_t kernmaxfilesize;
248 	ufs2_daddr_t ndb;
249 	mode_t mode;
250 	intmax_t size, fixsize;
251 	int j, ret, offset;
252 
253 	if ((dp = getnextinode(inumber, rebuildcg)) == NULL)
254 		goto unknown;
255 	mode = DIP(dp, di_mode) & IFMT;
256 	if (mode == 0) {
257 		if ((sblock.fs_magic == FS_UFS1_MAGIC &&
258 		     (memcmp(dp->dp1.di_db, ufs1_zino.di_db,
259 			UFS_NDADDR * sizeof(ufs1_daddr_t)) ||
260 		      memcmp(dp->dp1.di_ib, ufs1_zino.di_ib,
261 			UFS_NIADDR * sizeof(ufs1_daddr_t)) ||
262 		      dp->dp1.di_mode || dp->dp1.di_size)) ||
263 		    (sblock.fs_magic == FS_UFS2_MAGIC &&
264 		     (memcmp(dp->dp2.di_db, ufs2_zino.di_db,
265 			UFS_NDADDR * sizeof(ufs2_daddr_t)) ||
266 		      memcmp(dp->dp2.di_ib, ufs2_zino.di_ib,
267 			UFS_NIADDR * sizeof(ufs2_daddr_t)) ||
268 		      dp->dp2.di_mode || dp->dp2.di_size))) {
269 			pfatal("PARTIALLY ALLOCATED INODE I=%lu",
270 			    (u_long)inumber);
271 			if (reply("CLEAR") == 1) {
272 				dp = ginode(inumber);
273 				clearinode(dp);
274 				inodirty(dp);
275 			}
276 		}
277 		inoinfo(inumber)->ino_state = USTATE;
278 		return (1);
279 	}
280 	lastino = inumber;
281 	/* This should match the file size limit in ffs_mountfs(). */
282 	if (sblock.fs_magic == FS_UFS1_MAGIC)
283 		kernmaxfilesize = (off_t)0x40000000 * sblock.fs_bsize - 1;
284 	else
285 		kernmaxfilesize = sblock.fs_maxfilesize;
286 	if (DIP(dp, di_size) > kernmaxfilesize ||
287 	    DIP(dp, di_size) > sblock.fs_maxfilesize ||
288 	    (mode == IFDIR && DIP(dp, di_size) > MAXDIRSIZE)) {
289 		if (debug)
290 			printf("bad size %ju:", (uintmax_t)DIP(dp, di_size));
291 		goto unknown;
292 	}
293 	if (!preen && mode == IFMT && reply("HOLD BAD BLOCK") == 1) {
294 		dp = ginode(inumber);
295 		DIP_SET(dp, di_size, sblock.fs_fsize);
296 		DIP_SET(dp, di_mode, IFREG|0600);
297 		inodirty(dp);
298 	}
299 	if ((mode == IFBLK || mode == IFCHR || mode == IFIFO ||
300 	     mode == IFSOCK) && DIP(dp, di_size) != 0) {
301 		if (debug)
302 			printf("bad special-file size %ju:",
303 			    (uintmax_t)DIP(dp, di_size));
304 		goto unknown;
305 	}
306 	if ((mode == IFBLK || mode == IFCHR) &&
307 	    (dev_t)DIP(dp, di_rdev) == NODEV) {
308 		if (debug)
309 			printf("bad special-file rdev NODEV:");
310 		goto unknown;
311 	}
312 	ndb = howmany(DIP(dp, di_size), sblock.fs_bsize);
313 	if (ndb < 0) {
314 		if (debug)
315 			printf("bad size %ju ndb %ju:",
316 				(uintmax_t)DIP(dp, di_size), (uintmax_t)ndb);
317 		goto unknown;
318 	}
319 	if (mode == IFBLK || mode == IFCHR)
320 		ndb++;
321 	if (mode == IFLNK) {
322 		/*
323 		 * Fake ndb value so direct/indirect block checks below
324 		 * will detect any garbage after symlink string.
325 		 */
326 		if (DIP(dp, di_size) < (off_t)sblock.fs_maxsymlinklen) {
327 			if (sblock.fs_magic == FS_UFS1_MAGIC)
328 				ndb = howmany(DIP(dp, di_size),
329 				    sizeof(ufs1_daddr_t));
330 			else
331 				ndb = howmany(DIP(dp, di_size),
332 				    sizeof(ufs2_daddr_t));
333 			if (ndb > UFS_NDADDR) {
334 				j = ndb - UFS_NDADDR;
335 				for (ndb = 1; j > 1; j--)
336 					ndb *= NINDIR(&sblock);
337 				ndb += UFS_NDADDR;
338 			}
339 		}
340 	}
341 	for (j = ndb; ndb < UFS_NDADDR && j < UFS_NDADDR; j++)
342 		if (DIP(dp, di_db[j]) != 0) {
343 			if (debug)
344 				printf("bad direct addr[%d]: %ju\n", j,
345 				    (uintmax_t)DIP(dp, di_db[j]));
346 			goto unknown;
347 		}
348 	for (j = 0, ndb -= UFS_NDADDR; ndb > 0; j++)
349 		ndb /= NINDIR(&sblock);
350 	for (; j < UFS_NIADDR; j++)
351 		if (DIP(dp, di_ib[j]) != 0) {
352 			if (debug)
353 				printf("bad indirect addr: %ju\n",
354 				    (uintmax_t)DIP(dp, di_ib[j]));
355 			goto unknown;
356 		}
357 	if (ftypeok(dp) == 0)
358 		goto unknown;
359 	n_files++;
360 	inoinfo(inumber)->ino_linkcnt = DIP(dp, di_nlink);
361 	if (mode == IFDIR) {
362 		if (DIP(dp, di_size) == 0)
363 			inoinfo(inumber)->ino_state = DCLEAR;
364 		else if (DIP(dp, di_nlink) <= 0)
365 			inoinfo(inumber)->ino_state = DZLINK;
366 		else
367 			inoinfo(inumber)->ino_state = DSTATE;
368 		cacheino(dp, inumber);
369 		countdirs++;
370 	} else if (DIP(dp, di_nlink) <= 0)
371 		inoinfo(inumber)->ino_state = FZLINK;
372 	else
373 		inoinfo(inumber)->ino_state = FSTATE;
374 	inoinfo(inumber)->ino_type = IFTODT(mode);
375 	badblk = dupblk = 0;
376 	idesc->id_number = inumber;
377 	if (DIP(dp, di_flags) & SF_SNAPSHOT)
378 		idesc->id_type = SNAP;
379 	else
380 		idesc->id_type = ADDR;
381 	(void)ckinode(dp, idesc);
382 	if (sblock.fs_magic == FS_UFS2_MAGIC && dp->dp2.di_extsize > 0) {
383 		idesc->id_type = ADDR;
384 		ndb = howmany(dp->dp2.di_extsize, sblock.fs_bsize);
385 		for (j = 0; j < UFS_NXADDR; j++) {
386 			if (--ndb == 0 &&
387 			    (offset = blkoff(&sblock, dp->dp2.di_extsize)) != 0)
388 				idesc->id_numfrags = numfrags(&sblock,
389 				    fragroundup(&sblock, offset));
390 			else
391 				idesc->id_numfrags = sblock.fs_frag;
392 			if (dp->dp2.di_extb[j] == 0)
393 				continue;
394 			idesc->id_blkno = dp->dp2.di_extb[j];
395 			ret = (*idesc->id_func)(idesc);
396 			if (ret & STOP)
397 				break;
398 		}
399 	}
400 	if (sblock.fs_magic == FS_UFS2_MAGIC)
401 		eascan(idesc, &dp->dp2);
402 	idesc->id_entryno *= btodb(sblock.fs_fsize);
403 	if (DIP(dp, di_blocks) != idesc->id_entryno) {
404 		pwarn("INCORRECT BLOCK COUNT I=%lu (%ju should be %ju)",
405 		    (u_long)inumber, (uintmax_t)DIP(dp, di_blocks),
406 		    (uintmax_t)idesc->id_entryno);
407 		if (preen)
408 			printf(" (CORRECTED)\n");
409 		else if (reply("CORRECT") == 0)
410 			return (1);
411 		if (bkgrdflag == 0) {
412 			dp = ginode(inumber);
413 			DIP_SET(dp, di_blocks, idesc->id_entryno);
414 			inodirty(dp);
415 		} else {
416 			cmd.value = idesc->id_number;
417 			cmd.size = idesc->id_entryno - DIP(dp, di_blocks);
418 			if (debug)
419 				printf("adjblkcnt ino %ju amount %lld\n",
420 				    (uintmax_t)cmd.value, (long long)cmd.size);
421 			if (sysctl(adjblkcnt, MIBSIZE, 0, 0,
422 			    &cmd, sizeof cmd) == -1)
423 				rwerror("ADJUST INODE BLOCK COUNT", cmd.value);
424 		}
425 	}
426 	/*
427 	 * UFS does not allow files to end with a hole; it requires that
428 	 * the last block of a file be allocated. The last allocated block
429 	 * in a file is tracked in id_lballoc. Here, we check for a size
430 	 * past the last allocated block of the file and if that is found,
431 	 * shorten the file to reference the last allocated block to avoid
432 	 * having it reference a hole at its end.
433 	 *
434 	 * Soft updates will always ensure that the file size is correct
435 	 * for files that contain only direct block pointers. However
436 	 * soft updates does not roll back sizes for files with indirect
437 	 * blocks that it has set to unallocated because their contents
438 	 * have not yet been written to disk. Hence, the file can appear
439 	 * to have a hole at its end because the block pointer has been
440 	 * rolled back to zero. Thus finding a hole at the end of a file
441 	 * that is located in an indirect block receives only a warning
442 	 * while finding a hole at the end of a file in a direct block
443 	 * receives a fatal error message.
444 	 */
445 	size = DIP(dp, di_size);
446 	if (idesc->id_lballoc < lblkno(&sblock, size - 1) &&
447 	    /* exclude embedded symbolic links */
448 	    ((mode != IFLNK) || size >= sblock.fs_maxsymlinklen)) {
449  		fixsize = lblktosize(&sblock, idesc->id_lballoc + 1);
450 		if (size > UFS_NDADDR * sblock.fs_bsize)
451 			pwarn("INODE %lu: FILE SIZE %ju BEYOND END OF "
452 			      "ALLOCATED FILE, SIZE SHOULD BE %ju",
453 			      (u_long)inumber, size, fixsize);
454 		else
455 			pfatal("INODE %lu: FILE SIZE %ju BEYOND END OF "
456 			      "ALLOCATED FILE, SIZE SHOULD BE %ju",
457 			      (u_long)inumber, size, fixsize);
458 		if (preen)
459 			printf(" (ADJUSTED)\n");
460 		else if (reply("ADJUST") == 0)
461 			return (1);
462 		if (bkgrdflag == 0) {
463 			dp = ginode(inumber);
464 			DIP_SET(dp, di_size, fixsize);
465 			inodirty(dp);
466 		} else {
467 			cmd.value = idesc->id_number;
468 			cmd.size = fixsize;
469 			if (debug)
470 				printf("setsize ino %ju size set to %ju\n",
471 				    (uintmax_t)cmd.value, (uintmax_t)cmd.size);
472 			if (sysctl(setsize, MIBSIZE, 0, 0,
473 			    &cmd, sizeof cmd) == -1)
474 				rwerror("SET INODE SIZE", cmd.value);
475 		}
476 
477 	}
478 	return (1);
479 unknown:
480 	pfatal("UNKNOWN FILE TYPE I=%lu", (u_long)inumber);
481 	inoinfo(inumber)->ino_state = FCLEAR;
482 	if (reply("CLEAR") == 1) {
483 		inoinfo(inumber)->ino_state = USTATE;
484 		dp = ginode(inumber);
485 		clearinode(dp);
486 		inodirty(dp);
487 	}
488 	return (1);
489 }
490 
491 int
pass1check(struct inodesc * idesc)492 pass1check(struct inodesc *idesc)
493 {
494 	int res = KEEPON;
495 	int anyout, nfrags;
496 	ufs2_daddr_t blkno = idesc->id_blkno;
497 	struct dups *dlp;
498 	struct dups *new;
499 
500 	if (idesc->id_type == SNAP) {
501 		if (blkno == BLK_NOCOPY)
502 			return (KEEPON);
503 		if (idesc->id_number == cursnapshot) {
504 			if (blkno == blkstofrags(&sblock, idesc->id_lbn))
505 				return (KEEPON);
506 			if (blkno == BLK_SNAP) {
507 				blkno = blkstofrags(&sblock, idesc->id_lbn);
508 				idesc->id_entryno -= idesc->id_numfrags;
509 			}
510 		} else {
511 			if (blkno == BLK_SNAP)
512 				return (KEEPON);
513 		}
514 	}
515 	if ((anyout = chkrange(blkno, idesc->id_numfrags)) != 0) {
516 		blkerror(idesc->id_number, "BAD", blkno);
517 		if (badblk++ >= MAXBAD) {
518 			pwarn("EXCESSIVE BAD BLKS I=%lu",
519 			    (u_long)idesc->id_number);
520 			if (preen)
521 				printf(" (SKIPPING)\n");
522 			else if (reply("CONTINUE") == 0) {
523 				ckfini(0);
524 				exit(EEXIT);
525 			}
526 			rerun = 1;
527 			return (STOP);
528 		}
529 	}
530 	for (nfrags = idesc->id_numfrags; nfrags > 0; blkno++, nfrags--) {
531 		if (anyout && chkrange(blkno, 1)) {
532 			res = SKIP;
533 		} else if (!testbmap(blkno)) {
534 			n_blks++;
535 			setbmap(blkno);
536 		} else {
537 			blkerror(idesc->id_number, "DUP", blkno);
538 			if (dupblk++ >= MAXDUP) {
539 				pwarn("EXCESSIVE DUP BLKS I=%lu",
540 					(u_long)idesc->id_number);
541 				if (preen)
542 					printf(" (SKIPPING)\n");
543 				else if (reply("CONTINUE") == 0) {
544 					ckfini(0);
545 					exit(EEXIT);
546 				}
547 				rerun = 1;
548 				return (STOP);
549 			}
550 			new = (struct dups *)Malloc(sizeof(struct dups));
551 			if (new == NULL) {
552 				pfatal("DUP TABLE OVERFLOW.");
553 				if (reply("CONTINUE") == 0) {
554 					ckfini(0);
555 					exit(EEXIT);
556 				}
557 				rerun = 1;
558 				return (STOP);
559 			}
560 			new->dup = blkno;
561 			if (muldup == NULL) {
562 				duplist = muldup = new;
563 				new->next = NULL;
564 			} else {
565 				new->next = muldup->next;
566 				muldup->next = new;
567 			}
568 			for (dlp = duplist; dlp != muldup; dlp = dlp->next)
569 				if (dlp->dup == blkno)
570 					break;
571 			if (dlp == muldup && dlp->dup != blkno)
572 				muldup = new;
573 		}
574 		/*
575 		 * count the number of blocks found in id_entryno
576 		 */
577 		idesc->id_entryno++;
578 	}
579 	if (idesc->id_level == 0 && idesc->id_lballoc < idesc->id_lbn)
580 		idesc->id_lballoc = idesc->id_lbn;
581 	return (res);
582 }
583