xref: /freebsd/sbin/fsck_ffs/pass1.c (revision ec965063070e5753c166cf592c9336444b74720a)
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("$FreeBSD$");
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
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 		cgbp = cglookup(c);
101 		cgp = cgbp->b_un.b_cg;
102 		rebuildcg = 0;
103 		if (!check_cgmagic(c, cgbp, 1))
104 			rebuildcg = 1;
105 		if (!rebuildcg && sblock.fs_magic == FS_UFS2_MAGIC) {
106 			inosused = cgp->cg_initediblk;
107 			if (inosused > sblock.fs_ipg) {
108 				pfatal("Too many initialized inodes (%ju > %d) "
109 				    "in cylinder group %d\nReset to %d\n",
110 				    (uintmax_t)inosused, sblock.fs_ipg, c,
111 				    sblock.fs_ipg);
112 				inosused = sblock.fs_ipg;
113 			}
114 		} else {
115 			inosused = sblock.fs_ipg;
116 		}
117 		if (got_siginfo) {
118 			printf("%s: phase 1: cyl group %d of %d (%d%%)\n",
119 			    cdevname, c, sblock.fs_ncg,
120 			    c * 100 / sblock.fs_ncg);
121 			got_siginfo = 0;
122 		}
123 		if (got_sigalarm) {
124 			setproctitle("%s p1 %d%%", cdevname,
125 			     c * 100 / sblock.fs_ncg);
126 			got_sigalarm = 0;
127 		}
128 		/*
129 		 * If we are using soft updates, then we can trust the
130 		 * cylinder group inode allocation maps to tell us which
131 		 * inodes are allocated. We will scan the used inode map
132 		 * to find the inodes that are really in use, and then
133 		 * read only those inodes in from disk.
134 		 */
135 		if ((preen || inoopt) && usedsoftdep && !rebuildcg) {
136 			cp = &cg_inosused(cgp)[(inosused - 1) / CHAR_BIT];
137 			for ( ; inosused != 0; cp--) {
138 				if (*cp == 0) {
139 					if (inosused > CHAR_BIT)
140 						inosused -= CHAR_BIT;
141 					else
142 						inosused = 0;
143 					continue;
144 				}
145 				for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
146 					if (*cp & i)
147 						break;
148 					inosused--;
149 				}
150 				break;
151 			}
152 		}
153 		/*
154 		 * Allocate inoinfo structures for the allocated inodes.
155 		 */
156 		inostathead[c].il_numalloced = inosused;
157 		if (inosused == 0) {
158 			inostathead[c].il_stat = NULL;
159 			continue;
160 		}
161 		info = Calloc((unsigned)inosused, sizeof(struct inostat));
162 		if (info == NULL)
163 			errx(EEXIT, "cannot alloc %u bytes for inoinfo",
164 			    (unsigned)(sizeof(struct inostat) * inosused));
165 		inostathead[c].il_stat = info;
166 		/*
167 		 * Scan the allocated inodes.
168 		 */
169 		setinodebuf(c, inosused);
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 			cgdirty(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
244 checkinode(ino_t inumber, struct inodesc *idesc, int rebuildcg)
245 {
246 	struct inode ip;
247 	union dinode *dp;
248 	off_t kernmaxfilesize;
249 	ufs2_daddr_t ndb;
250 	mode_t mode;
251 	intmax_t size, fixsize;
252 	int j, ret, offset;
253 
254 	if ((dp = getnextinode(inumber, rebuildcg)) == NULL) {
255 		pfatal("INVALID INODE");
256 		goto unknown;
257 	}
258 	mode = DIP(dp, di_mode) & IFMT;
259 	if (mode == 0) {
260 		if ((sblock.fs_magic == FS_UFS1_MAGIC &&
261 		     (memcmp(dp->dp1.di_db, zino.dp1.di_db,
262 			UFS_NDADDR * sizeof(ufs1_daddr_t)) ||
263 		      memcmp(dp->dp1.di_ib, zino.dp1.di_ib,
264 			UFS_NIADDR * sizeof(ufs1_daddr_t)) ||
265 		      dp->dp1.di_mode || dp->dp1.di_size)) ||
266 		    (sblock.fs_magic == FS_UFS2_MAGIC &&
267 		     (memcmp(dp->dp2.di_db, zino.dp2.di_db,
268 			UFS_NDADDR * sizeof(ufs2_daddr_t)) ||
269 		      memcmp(dp->dp2.di_ib, zino.dp2.di_ib,
270 			UFS_NIADDR * sizeof(ufs2_daddr_t)) ||
271 		      dp->dp2.di_mode || dp->dp2.di_size))) {
272 			pfatal("PARTIALLY ALLOCATED INODE I=%lu",
273 			    (u_long)inumber);
274 			if (reply("CLEAR") == 1) {
275 				ginode(inumber, &ip);
276 				clearinode(ip.i_dp);
277 				inodirty(&ip);
278 				irelse(&ip);
279 			}
280 		}
281 		inoinfo(inumber)->ino_state = USTATE;
282 		return (1);
283 	}
284 	lastino = inumber;
285 	/* This should match the file size limit in ffs_mountfs(). */
286 	if (sblock.fs_magic == FS_UFS1_MAGIC)
287 		kernmaxfilesize = (off_t)0x40000000 * sblock.fs_bsize - 1;
288 	else
289 		kernmaxfilesize = sblock.fs_maxfilesize;
290 	if (DIP(dp, di_size) > kernmaxfilesize ||
291 	    DIP(dp, di_size) > sblock.fs_maxfilesize ||
292 	    (mode == IFDIR && DIP(dp, di_size) > MAXDIRSIZE)) {
293 		if (debug)
294 			printf("bad size %ju:", (uintmax_t)DIP(dp, di_size));
295 		pfatal("BAD FILE SIZE");
296 		goto unknown;
297 	}
298 	if (!preen && mode == IFMT && reply("HOLD BAD BLOCK") == 1) {
299 		ginode(inumber, &ip);
300 		dp = ip.i_dp;
301 		DIP_SET(dp, di_size, sblock.fs_fsize);
302 		DIP_SET(dp, di_mode, IFREG|0600);
303 		inodirty(&ip);
304 		irelse(&ip);
305 	}
306 	if ((mode == IFBLK || mode == IFCHR || mode == IFIFO ||
307 	     mode == IFSOCK) && DIP(dp, di_size) != 0) {
308 		if (debug)
309 			printf("bad special-file size %ju:",
310 			    (uintmax_t)DIP(dp, di_size));
311 		pfatal("BAD SPECIAL-FILE SIZE");
312 		goto unknown;
313 	}
314 	if ((mode == IFBLK || mode == IFCHR) &&
315 	    (dev_t)DIP(dp, di_rdev) == NODEV) {
316 		if (debug)
317 			printf("bad special-file rdev NODEV:");
318 		pfatal("BAD SPECIAL-FILE RDEV");
319 		goto unknown;
320 	}
321 	ndb = howmany(DIP(dp, di_size), sblock.fs_bsize);
322 	if (ndb < 0) {
323 		if (debug)
324 			printf("negative size %ju ndb %ju:",
325 				(uintmax_t)DIP(dp, di_size), (uintmax_t)ndb);
326 		pfatal("NEGATIVE FILE SIZE");
327 		goto unknown;
328 	}
329 	if (mode == IFBLK || mode == IFCHR)
330 		ndb++;
331 	if (mode == IFLNK) {
332 		/*
333 		 * Fake ndb value so direct/indirect block checks below
334 		 * will detect any garbage after symlink string.
335 		 */
336 		if (DIP(dp, di_size) < (off_t)sblock.fs_maxsymlinklen) {
337 			if (sblock.fs_magic == FS_UFS1_MAGIC)
338 				ndb = howmany(DIP(dp, di_size),
339 				    sizeof(ufs1_daddr_t));
340 			else
341 				ndb = howmany(DIP(dp, di_size),
342 				    sizeof(ufs2_daddr_t));
343 			if (ndb > UFS_NDADDR) {
344 				j = ndb - UFS_NDADDR;
345 				for (ndb = 1; j > 1; j--)
346 					ndb *= NINDIR(&sblock);
347 				ndb += UFS_NDADDR;
348 			}
349 		}
350 	}
351 	for (j = ndb; ndb < UFS_NDADDR && j < UFS_NDADDR; j++)
352 		if (DIP(dp, di_db[j]) != 0) {
353 			if (debug)
354 				printf("invalid direct addr[%d]: %ju\n", j,
355 				    (uintmax_t)DIP(dp, di_db[j]));
356 			pfatal("INVALID DIRECT BLOCK");
357 			goto unknown;
358 		}
359 	for (j = 0, ndb -= UFS_NDADDR; ndb > 0; j++)
360 		ndb /= NINDIR(&sblock);
361 	for (; j < UFS_NIADDR; j++)
362 		if (DIP(dp, di_ib[j]) != 0) {
363 			if (debug)
364 				printf("invalid indirect addr: %ju\n",
365 				    (uintmax_t)DIP(dp, di_ib[j]));
366 			pfatal("INVALID INDIRECT BLOCK");
367 			goto unknown;
368 		}
369 	if (ftypeok(dp) == 0) {
370 		pfatal("UNKNOWN FILE TYPE");
371 		goto unknown;
372 	}
373 	n_files++;
374 	inoinfo(inumber)->ino_linkcnt = DIP(dp, di_nlink);
375 	if (mode == IFDIR) {
376 		if (DIP(dp, di_size) == 0)
377 			inoinfo(inumber)->ino_state = DCLEAR;
378 		else if (DIP(dp, di_nlink) <= 0)
379 			inoinfo(inumber)->ino_state = DZLINK;
380 		else
381 			inoinfo(inumber)->ino_state = DSTATE;
382 		cacheino(dp, inumber);
383 		countdirs++;
384 	} else if (DIP(dp, di_nlink) <= 0)
385 		inoinfo(inumber)->ino_state = FZLINK;
386 	else
387 		inoinfo(inumber)->ino_state = FSTATE;
388 	inoinfo(inumber)->ino_type = IFTODT(mode);
389 	badblk = dupblk = 0;
390 	idesc->id_number = inumber;
391 	if (DIP(dp, di_flags) & SF_SNAPSHOT)
392 		inoinfo(inumber)->ino_idtype = SNAP;
393 	else
394 		inoinfo(inumber)->ino_idtype = ADDR;
395 	idesc->id_type = inoinfo(inumber)->ino_idtype;
396 	(void)ckinode(dp, idesc);
397 	if (sblock.fs_magic == FS_UFS2_MAGIC && dp->dp2.di_extsize > 0) {
398 		ndb = howmany(dp->dp2.di_extsize, sblock.fs_bsize);
399 		for (j = 0; j < UFS_NXADDR; j++) {
400 			if (--ndb == 0 &&
401 			    (offset = blkoff(&sblock, dp->dp2.di_extsize)) != 0)
402 				idesc->id_numfrags = numfrags(&sblock,
403 				    fragroundup(&sblock, offset));
404 			else
405 				idesc->id_numfrags = sblock.fs_frag;
406 			if (dp->dp2.di_extb[j] == 0)
407 				continue;
408 			idesc->id_blkno = dp->dp2.di_extb[j];
409 			ret = (*idesc->id_func)(idesc);
410 			if (ret & STOP)
411 				break;
412 		}
413 	}
414 	if (sblock.fs_magic == FS_UFS2_MAGIC)
415 		eascan(idesc, &dp->dp2);
416 	idesc->id_entryno *= btodb(sblock.fs_fsize);
417 	if (DIP(dp, di_blocks) != idesc->id_entryno) {
418 		pwarn("INCORRECT BLOCK COUNT I=%lu (%ju should be %ju)",
419 		    (u_long)inumber, (uintmax_t)DIP(dp, di_blocks),
420 		    (uintmax_t)idesc->id_entryno);
421 		if (preen)
422 			printf(" (CORRECTED)\n");
423 		else if (reply("CORRECT") == 0)
424 			return (1);
425 		if (bkgrdflag == 0) {
426 			ginode(inumber, &ip);
427 			DIP_SET(ip.i_dp, di_blocks, idesc->id_entryno);
428 			inodirty(&ip);
429 			irelse(&ip);
430 		} else {
431 			cmd.value = idesc->id_number;
432 			cmd.size = idesc->id_entryno - DIP(dp, di_blocks);
433 			if (debug)
434 				printf("adjblkcnt ino %ju amount %lld\n",
435 				    (uintmax_t)cmd.value, (long long)cmd.size);
436 			if (sysctl(adjblkcnt, MIBSIZE, 0, 0,
437 			    &cmd, sizeof cmd) == -1)
438 				rwerror("ADJUST INODE BLOCK COUNT", cmd.value);
439 		}
440 	}
441 	/*
442 	 * UFS does not allow files to end with a hole; it requires that
443 	 * the last block of a file be allocated. The last allocated block
444 	 * in a file is tracked in id_lballoc. Here, we check for a size
445 	 * past the last allocated block of the file and if that is found,
446 	 * shorten the file to reference the last allocated block to avoid
447 	 * having it reference a hole at its end.
448 	 *
449 	 * Soft updates will always ensure that the file size is correct
450 	 * for files that contain only direct block pointers. However
451 	 * soft updates does not roll back sizes for files with indirect
452 	 * blocks that it has set to unallocated because their contents
453 	 * have not yet been written to disk. Hence, the file can appear
454 	 * to have a hole at its end because the block pointer has been
455 	 * rolled back to zero. Thus finding a hole at the end of a file
456 	 * that is located in an indirect block receives only a warning
457 	 * while finding a hole at the end of a file in a direct block
458 	 * receives a fatal error message.
459 	 */
460 	size = DIP(dp, di_size);
461 	if (idesc->id_lballoc < lblkno(&sblock, size - 1) &&
462 	    /* exclude embedded symbolic links */
463 	    ((mode != IFLNK) || size >= sblock.fs_maxsymlinklen)) {
464  		fixsize = lblktosize(&sblock, idesc->id_lballoc + 1);
465 		if (size > UFS_NDADDR * sblock.fs_bsize)
466 			pwarn("INODE %lu: FILE SIZE %ju BEYOND END OF "
467 			      "ALLOCATED FILE, SIZE SHOULD BE %ju",
468 			      (u_long)inumber, size, fixsize);
469 		else
470 			pfatal("INODE %lu: FILE SIZE %ju BEYOND END OF "
471 			      "ALLOCATED FILE, SIZE SHOULD BE %ju",
472 			      (u_long)inumber, size, fixsize);
473 		if (preen)
474 			printf(" (ADJUSTED)\n");
475 		else if (reply("ADJUST") == 0)
476 			return (1);
477 		if (bkgrdflag == 0) {
478 			ginode(inumber, &ip);
479 			DIP_SET(ip.i_dp, di_size, fixsize);
480 			inodirty(&ip);
481 			irelse(&ip);
482 		} else {
483 			cmd.value = idesc->id_number;
484 			cmd.size = fixsize;
485 			if (debug)
486 				printf("setsize ino %ju size set to %ju\n",
487 				    (uintmax_t)cmd.value, (uintmax_t)cmd.size);
488 			if (sysctl(setsize, MIBSIZE, 0, 0,
489 			    &cmd, sizeof cmd) == -1)
490 				rwerror("SET INODE SIZE", cmd.value);
491 		}
492 
493 	}
494 	return (1);
495 unknown:
496 	ginode(inumber, &ip);
497 	prtinode(&ip);
498 	inoinfo(inumber)->ino_state = USTATE;
499 	if (reply("CLEAR") == 1) {
500 		clearinode(ip.i_dp);
501 		inodirty(&ip);
502 	}
503 	irelse(&ip);
504 	return (1);
505 }
506 
507 int
508 pass1check(struct inodesc *idesc)
509 {
510 	int res = KEEPON;
511 	int anyout, nfrags;
512 	ufs2_daddr_t blkno = idesc->id_blkno;
513 	struct dups *dlp;
514 	struct dups *new;
515 
516 	if (idesc->id_type == SNAP) {
517 		if (blkno == BLK_NOCOPY)
518 			return (KEEPON);
519 		if (idesc->id_number == cursnapshot) {
520 			if (blkno == blkstofrags(&sblock, idesc->id_lbn))
521 				return (KEEPON);
522 			if (blkno == BLK_SNAP) {
523 				blkno = blkstofrags(&sblock, idesc->id_lbn);
524 				idesc->id_entryno -= idesc->id_numfrags;
525 			}
526 		} else {
527 			if (blkno == BLK_SNAP)
528 				return (KEEPON);
529 		}
530 	}
531 	if ((anyout = chkrange(blkno, idesc->id_numfrags)) != 0) {
532 		blkerror(idesc->id_number, "BAD", blkno);
533 		if (badblk++ >= MAXBAD) {
534 			pwarn("EXCESSIVE BAD BLKS I=%lu",
535 			    (u_long)idesc->id_number);
536 			if (preen)
537 				printf(" (SKIPPING)\n");
538 			else if (reply("CONTINUE") == 0) {
539 				ckfini(0);
540 				exit(EEXIT);
541 			}
542 			rerun = 1;
543 			return (STOP);
544 		}
545 	}
546 	for (nfrags = idesc->id_numfrags; nfrags > 0; blkno++, nfrags--) {
547 		if (anyout && chkrange(blkno, 1)) {
548 			res = SKIP;
549 		} else if (!testbmap(blkno)) {
550 			n_blks++;
551 			setbmap(blkno);
552 		} else {
553 			blkerror(idesc->id_number, "DUP", blkno);
554 			if (dupblk++ >= MAXDUP) {
555 				pwarn("EXCESSIVE DUP BLKS I=%lu",
556 					(u_long)idesc->id_number);
557 				if (preen)
558 					printf(" (SKIPPING)\n");
559 				else if (reply("CONTINUE") == 0) {
560 					ckfini(0);
561 					exit(EEXIT);
562 				}
563 				rerun = 1;
564 				return (STOP);
565 			}
566 			new = (struct dups *)Malloc(sizeof(struct dups));
567 			if (new == NULL) {
568 				pfatal("DUP TABLE OVERFLOW.");
569 				if (reply("CONTINUE") == 0) {
570 					ckfini(0);
571 					exit(EEXIT);
572 				}
573 				rerun = 1;
574 				return (STOP);
575 			}
576 			new->dup = blkno;
577 			if (muldup == NULL) {
578 				duplist = muldup = new;
579 				new->next = NULL;
580 			} else {
581 				new->next = muldup->next;
582 				muldup->next = new;
583 			}
584 			for (dlp = duplist; dlp != muldup; dlp = dlp->next)
585 				if (dlp->dup == blkno)
586 					break;
587 			if (dlp == muldup && dlp->dup != blkno)
588 				muldup = new;
589 		}
590 		/*
591 		 * count the number of blocks found in id_entryno
592 		 */
593 		idesc->id_entryno++;
594 	}
595 	if (idesc->id_level == 0 && idesc->id_lballoc < idesc->id_lbn)
596 		idesc->id_lballoc = idesc->id_lbn;
597 	return (res);
598 }
599