xref: /freebsd/sbin/fsck_ffs/pass1.c (revision 32e86a82f54826f14ea381affa6674db3aa3b5ae)
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 #include <sys/param.h>
33 #include <sys/stat.h>
34 #include <sys/sysctl.h>
35 
36 #include <ufs/ufs/dinode.h>
37 #include <ufs/ufs/dir.h>
38 #include <ufs/ffs/fs.h>
39 
40 #include <err.h>
41 #include <limits.h>
42 #include <stdint.h>
43 #include <string.h>
44 
45 #include "fsck.h"
46 
47 static ufs2_daddr_t badblk;
48 static ufs2_daddr_t dupblk;
49 static ino_t lastino;		/* last inode in use */
50 
51 static int checkinode(ino_t inumber, struct inodesc *, int rebuiltcg);
52 
53 void
pass1(void)54 pass1(void)
55 {
56 	struct inostat *info;
57 	struct inodesc idesc;
58 	struct bufarea *cgbp;
59 	struct cg *cgp;
60 	ino_t inumber, inosused, mininos;
61 	ufs2_daddr_t i, cgd;
62 	u_int8_t *cp;
63 	int c, rebuiltcg;
64 
65 	badblk = dupblk = lastino = 0;
66 
67 	/*
68 	 * Set file system reserved blocks in used block map.
69 	 */
70 	for (c = 0; c < sblock.fs_ncg; c++) {
71 		cgd = cgdmin(&sblock, c);
72 		if (c == 0) {
73 			i = cgbase(&sblock, c);
74 		} else
75 			i = cgsblock(&sblock, c);
76 		for (; i < cgd; i++)
77 			setbmap(i);
78 	}
79 	i = sblock.fs_csaddr;
80 	cgd = i + howmany(sblock.fs_cssize, sblock.fs_fsize);
81 	for (; i < cgd; i++)
82 		setbmap(i);
83 
84 	/*
85 	 * Find all allocated blocks.
86 	 */
87 	memset(&idesc, 0, sizeof(struct inodesc));
88 	idesc.id_func = pass1check;
89 	n_files = n_blks = 0;
90 	for (c = 0; c < sblock.fs_ncg; c++) {
91 		inumber = c * sblock.fs_ipg;
92 		cgbp = cglookup(c);
93 		cgp = cgbp->b_un.b_cg;
94 		rebuiltcg = 0;
95 		if (!check_cgmagic(c, cgbp)) {
96 			if (!reply("REBUILD CYLINDER GROUP")) {
97 				cgheader_corrupt = 1;
98 				if (!nflag) {
99 					pwarn("YOU WILL NEED TO RERUN FSCK.\n");
100 					rerun = 1;
101 				}
102 			} else {
103 				rebuild_cg(c, cgbp);
104 				rebuiltcg = 1;
105 			}
106 		}
107 		if (!rebuiltcg && sblock.fs_magic == FS_UFS2_MAGIC) {
108 			inosused = cgp->cg_initediblk;
109 			if (inosused > sblock.fs_ipg) {
110 				pfatal("Too many initialized inodes (%ju > %d) "
111 				    "in cylinder group %d\nReset to %d\n",
112 				    (uintmax_t)inosused, sblock.fs_ipg, c,
113 				    sblock.fs_ipg);
114 				inosused = sblock.fs_ipg;
115 			}
116 		} else {
117 			inosused = sblock.fs_ipg;
118 		}
119 		if (got_siginfo) {
120 			printf("%s: phase 1: cyl group %d of %d (%d%%)\n",
121 			    cdevname, c, sblock.fs_ncg,
122 			    c * 100 / sblock.fs_ncg);
123 			got_siginfo = 0;
124 		}
125 		if (got_sigalarm) {
126 			setproctitle("%s p1 %d%%", cdevname,
127 			     c * 100 / sblock.fs_ncg);
128 			got_sigalarm = 0;
129 		}
130 		/*
131 		 * If we are using soft updates, then we can trust the
132 		 * cylinder group inode allocation maps to tell us which
133 		 * inodes are allocated. We will scan the used inode map
134 		 * to find the inodes that are really in use, and then
135 		 * read only those inodes in from disk.
136 		 */
137 		if ((preen || inoopt) && usedsoftdep && !rebuiltcg) {
138 			cp = &cg_inosused(cgp)[(inosused - 1) / CHAR_BIT];
139 			for ( ; inosused != 0; cp--) {
140 				if (*cp == 0) {
141 					if (inosused > CHAR_BIT)
142 						inosused -= CHAR_BIT;
143 					else
144 						inosused = 0;
145 					continue;
146 				}
147 				for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
148 					if (*cp & i)
149 						break;
150 					inosused--;
151 				}
152 				break;
153 			}
154 		}
155 		/*
156 		 * Allocate inoinfo structures for the allocated inodes.
157 		 */
158 		inostathead[c].il_numalloced = inosused;
159 		if (inosused == 0) {
160 			inostathead[c].il_stat = NULL;
161 			continue;
162 		}
163 		info = Calloc((unsigned)inosused, sizeof(struct inostat));
164 		if (info == NULL)
165 			errx(EEXIT, "cannot alloc %u bytes for inoinfo",
166 			    (unsigned)(sizeof(struct inostat) * inosused));
167 		inostathead[c].il_stat = info;
168 		/*
169 		 * Scan the allocated inodes.
170 		 */
171 		setinodebuf(c, inosused);
172 		for (i = 0; i < inosused; i++, inumber++) {
173 			if (inumber < UFS_ROOTINO) {
174 				(void)getnextinode(inumber, rebuiltcg);
175 				continue;
176 			}
177 			/*
178 			 * NULL return indicates probable end of allocated
179 			 * inodes during cylinder group rebuild attempt.
180 			 * We always keep trying until we get to the minimum
181 			 * valid number for this cylinder group.
182 			 */
183 			if (checkinode(inumber, &idesc, rebuiltcg) == 0 &&
184 			    i > cgp->cg_initediblk)
185 				break;
186 		}
187 		/*
188 		 * This optimization speeds up future runs of fsck
189 		 * by trimming down the number of inodes in cylinder
190 		 * groups that formerly had many inodes but now have
191 		 * fewer in use.
192 		 */
193 		mininos = roundup(inosused + INOPB(&sblock), INOPB(&sblock));
194 		if (inoopt && !preen && !rebuiltcg &&
195 		    sblock.fs_magic == FS_UFS2_MAGIC &&
196 		    cgp->cg_initediblk > 2 * INOPB(&sblock) &&
197 		    mininos < cgp->cg_initediblk) {
198 			i = cgp->cg_initediblk;
199 			if (mininos < 2 * INOPB(&sblock))
200 				cgp->cg_initediblk = 2 * INOPB(&sblock);
201 			else
202 				cgp->cg_initediblk = mininos;
203 			pwarn("CYLINDER GROUP %d: RESET FROM %ju TO %d %s\n",
204 			    c, i, cgp->cg_initediblk, "VALID INODES");
205 			cgdirty(cgbp);
206 		}
207 		if (inosused < sblock.fs_ipg)
208 			continue;
209 		lastino += 1;
210 		if (lastino < (c * sblock.fs_ipg))
211 			inosused = 0;
212 		else
213 			inosused = lastino - (c * sblock.fs_ipg);
214 		if (rebuiltcg && inosused > cgp->cg_initediblk &&
215 		    sblock.fs_magic == FS_UFS2_MAGIC) {
216 			cgp->cg_initediblk = roundup(inosused, INOPB(&sblock));
217 			pwarn("CYLINDER GROUP %d: FOUND %d VALID INODES\n", c,
218 			    cgp->cg_initediblk);
219 		}
220 		/*
221 		 * If we were not able to determine in advance which inodes
222 		 * were in use, then reduce the size of the inoinfo structure
223 		 * to the size necessary to describe the inodes that we
224 		 * really found. Always leave map space in the first cylinder
225 		 * group in case we need to a root or lost+found directory.
226 		 */
227 		if (inumber == lastino || c == 0)
228 			continue;
229 		inostathead[c].il_numalloced = inosused;
230 		if (inosused == 0) {
231 			free(inostathead[c].il_stat);
232 			inostathead[c].il_stat = NULL;
233 			continue;
234 		}
235 		info = Calloc((unsigned)inosused, sizeof(struct inostat));
236 		if (info == NULL)
237 			errx(EEXIT, "cannot alloc %u bytes for inoinfo",
238 			    (unsigned)(sizeof(struct inostat) * inosused));
239 		memmove(info, inostathead[c].il_stat, inosused * sizeof(*info));
240 		free(inostathead[c].il_stat);
241 		inostathead[c].il_stat = info;
242 	}
243 	freeinodebuf();
244 }
245 
246 static int
checkinode(ino_t inumber,struct inodesc * idesc,int rebuiltcg)247 checkinode(ino_t inumber, struct inodesc *idesc, int rebuiltcg)
248 {
249 	struct inode ip;
250 	union dinode *dp;
251 	ufs2_daddr_t ndb;
252 	mode_t mode;
253 	intmax_t size, fixsize;
254 	int j, ret, offset;
255 
256 	if ((dp = getnextinode(inumber, rebuiltcg)) == NULL) {
257 		pfatal("INVALID INODE");
258 		goto unknown;
259 	}
260 	mode = DIP(dp, di_mode) & IFMT;
261 	if (mode == 0) {
262 		if ((sblock.fs_magic == FS_UFS1_MAGIC &&
263 		     (memcmp(dp->dp1.di_db, zino.dp1.di_db,
264 			UFS_NDADDR * sizeof(ufs1_daddr_t)) ||
265 		      memcmp(dp->dp1.di_ib, zino.dp1.di_ib,
266 			UFS_NIADDR * sizeof(ufs1_daddr_t)) ||
267 		      dp->dp1.di_mode || dp->dp1.di_size)) ||
268 		    (sblock.fs_magic == FS_UFS2_MAGIC &&
269 		     (memcmp(dp->dp2.di_db, zino.dp2.di_db,
270 			UFS_NDADDR * sizeof(ufs2_daddr_t)) ||
271 		      memcmp(dp->dp2.di_ib, zino.dp2.di_ib,
272 			UFS_NIADDR * sizeof(ufs2_daddr_t)) ||
273 		      dp->dp2.di_mode || dp->dp2.di_size))) {
274 			pfatal("PARTIALLY ALLOCATED INODE I=%lu",
275 			    (u_long)inumber);
276 			if (reply("CLEAR") == 1) {
277 				ginode(inumber, &ip);
278 				clearinode(ip.i_dp);
279 				inodirty(&ip);
280 				irelse(&ip);
281 			}
282 		}
283 		inoinfo(inumber)->ino_state = USTATE;
284 		return (1);
285 	}
286 	lastino = inumber;
287 	if (chkfilesize(mode, DIP(dp, di_size)) == 0) {
288 		pfatal("BAD FILE SIZE");
289 		goto unknown;
290 	}
291 	if (!preen && mode == IFMT && reply("HOLD BAD BLOCK") == 1) {
292 		ginode(inumber, &ip);
293 		dp = ip.i_dp;
294 		DIP_SET(dp, di_size, sblock.fs_fsize);
295 		DIP_SET(dp, di_mode, IFREG|0600);
296 		inodirty(&ip);
297 		irelse(&ip);
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 		pfatal("BAD SPECIAL-FILE SIZE");
305 		goto unknown;
306 	}
307 	if ((mode == IFBLK || mode == IFCHR) &&
308 	    (dev_t)DIP(dp, di_rdev) == NODEV) {
309 		if (debug)
310 			printf("bad special-file rdev NODEV:");
311 		pfatal("BAD SPECIAL-FILE RDEV");
312 		goto unknown;
313 	}
314 	ndb = howmany(DIP(dp, di_size), sblock.fs_bsize);
315 	if (ndb < 0) {
316 		if (debug)
317 			printf("negative size %ju ndb %ju:",
318 				(uintmax_t)DIP(dp, di_size), (uintmax_t)ndb);
319 		pfatal("NEGATIVE FILE SIZE");
320 		goto unknown;
321 	}
322 	if (mode == IFBLK || mode == IFCHR)
323 		ndb++;
324 	if (mode == IFLNK) {
325 		/*
326 		 * Fake ndb value so direct/indirect block checks below
327 		 * will detect any garbage after symlink string.
328 		 */
329 		if (DIP(dp, di_size) < (off_t)sblock.fs_maxsymlinklen) {
330 			if (sblock.fs_magic == FS_UFS1_MAGIC)
331 				ndb = howmany(DIP(dp, di_size),
332 				    sizeof(ufs1_daddr_t));
333 			else
334 				ndb = howmany(DIP(dp, di_size),
335 				    sizeof(ufs2_daddr_t));
336 			if (ndb > UFS_NDADDR) {
337 				j = ndb - UFS_NDADDR;
338 				for (ndb = 1; j > 1; j--)
339 					ndb *= NINDIR(&sblock);
340 				ndb += UFS_NDADDR;
341 			}
342 		}
343 	}
344 	for (j = ndb; ndb < UFS_NDADDR && j < UFS_NDADDR; j++) {
345 		if (DIP(dp, di_db[j]) == 0)
346 			continue;
347 		if (debug)
348 			printf("invalid direct addr[%d]: %ju\n", j,
349 			    (uintmax_t)DIP(dp, di_db[j]));
350 		pfatal("INVALID DIRECT BLOCK");
351 		ginode(inumber, &ip);
352 		prtinode(&ip);
353 		if (reply("CLEAR") == 1) {
354 			DIP_SET(ip.i_dp, di_db[j], 0);
355 			inodirty(&ip);
356 		}
357 		irelse(&ip);
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 			continue;
364 		if (debug)
365 			printf("invalid indirect addr: %ju\n",
366 			    (uintmax_t)DIP(dp, di_ib[j]));
367 		pfatal("INVALID INDIRECT BLOCK");
368 		ginode(inumber, &ip);
369 		prtinode(&ip);
370 		if (reply("CLEAR") == 1) {
371 			DIP_SET(ip.i_dp, di_ib[j], 0);
372 			inodirty(&ip);
373 		}
374 		irelse(&ip);
375 	}
376 	if (ftypeok(dp) == 0) {
377 		pfatal("UNKNOWN FILE TYPE");
378 		goto unknown;
379 	}
380 	n_files++;
381 	inoinfo(inumber)->ino_linkcnt = DIP(dp, di_nlink);
382 	if (mode == IFDIR) {
383 		if (DIP(dp, di_size) == 0) {
384 			inoinfo(inumber)->ino_state = DCLEAR;
385 		} else if (DIP(dp, di_nlink) == 0) {
386 			inoinfo(inumber)->ino_state = DZLINK;
387 		} else {
388 			inoinfo(inumber)->ino_state = DSTATE;
389 		}
390 		cacheino(dp, inumber);
391 		countdirs++;
392 	} else if (DIP(dp, di_nlink) <= 0)
393 		inoinfo(inumber)->ino_state = FZLINK;
394 	else
395 		inoinfo(inumber)->ino_state = FSTATE;
396 	inoinfo(inumber)->ino_type = IFTODT(mode);
397 	badblk = dupblk = 0;
398 	idesc->id_number = inumber;
399 	if (DIP(dp, di_flags) & SF_SNAPSHOT)
400 		inoinfo(inumber)->ino_idtype = SNAP;
401 	else
402 		inoinfo(inumber)->ino_idtype = ADDR;
403 	idesc->id_type = inoinfo(inumber)->ino_idtype;
404 	(void)ckinode(dp, idesc);
405 	if (sblock.fs_magic == FS_UFS2_MAGIC && dp->dp2.di_extsize > 0) {
406 		ndb = howmany(dp->dp2.di_extsize, sblock.fs_bsize);
407 		for (j = 0; j < UFS_NXADDR; j++) {
408 			if (--ndb == 0 &&
409 			    (offset = blkoff(&sblock, dp->dp2.di_extsize)) != 0)
410 				idesc->id_numfrags = numfrags(&sblock,
411 				    fragroundup(&sblock, offset));
412 			else
413 				idesc->id_numfrags = sblock.fs_frag;
414 			if (dp->dp2.di_extb[j] == 0)
415 				continue;
416 			idesc->id_blkno = dp->dp2.di_extb[j];
417 			ret = (*idesc->id_func)(idesc);
418 			if (ret & STOP)
419 				break;
420 		}
421 	}
422 	if (sblock.fs_magic == FS_UFS2_MAGIC)
423 		eascan(idesc, &dp->dp2);
424 	idesc->id_entryno *= btodb(sblock.fs_fsize);
425 	if (DIP(dp, di_blocks) != idesc->id_entryno) {
426 		pwarn("INCORRECT BLOCK COUNT I=%lu (%ju should be %ju)",
427 		    (u_long)inumber, (uintmax_t)DIP(dp, di_blocks),
428 		    (uintmax_t)idesc->id_entryno);
429 		if (preen)
430 			printf(" (CORRECTED)\n");
431 		else if (reply("CORRECT") == 0)
432 			return (1);
433 		if (bkgrdflag == 0) {
434 			ginode(inumber, &ip);
435 			DIP_SET(ip.i_dp, di_blocks, idesc->id_entryno);
436 			inodirty(&ip);
437 			irelse(&ip);
438 		} else {
439 			cmd.value = idesc->id_number;
440 			cmd.size = idesc->id_entryno - DIP(dp, di_blocks);
441 			if (debug)
442 				printf("adjblkcnt ino %ju amount %lld\n",
443 				    (uintmax_t)cmd.value, (long long)cmd.size);
444 			if (sysctl(adjblkcnt, MIBSIZE, 0, 0,
445 			    &cmd, sizeof cmd) == -1)
446 				rwerror("ADJUST INODE BLOCK COUNT", cmd.value);
447 		}
448 	}
449 	/*
450 	 * UFS does not allow files to end with a hole; it requires that
451 	 * the last block of a file be allocated. The last allocated block
452 	 * in a file is tracked in id_lballoc. Here, we check for a size
453 	 * past the last allocated block of the file and if that is found,
454 	 * shorten the file to reference the last allocated block to avoid
455 	 * having it reference a hole at its end.
456 	 *
457 	 * Soft updates will always ensure that the file size is correct
458 	 * for files that contain only direct block pointers. However
459 	 * soft updates does not roll back sizes for files with indirect
460 	 * blocks that it has set to unallocated because their contents
461 	 * have not yet been written to disk. Hence, the file can appear
462 	 * to have a hole at its end because the block pointer has been
463 	 * rolled back to zero. Thus finding a hole at the end of a file
464 	 * that is located in an indirect block receives only a warning
465 	 * while finding a hole at the end of a file in a direct block
466 	 * receives a fatal error message.
467 	 */
468 	size = DIP(dp, di_size);
469 	if (idesc->id_lballoc < lblkno(&sblock, size - 1) &&
470 	    /* exclude embedded symbolic links */
471 	    ((mode != IFLNK) || size >= sblock.fs_maxsymlinklen)) {
472  		fixsize = lblktosize(&sblock, idesc->id_lballoc + 1);
473 		if (size > UFS_NDADDR * sblock.fs_bsize)
474 			pwarn("INODE %lu: FILE SIZE %ju BEYOND END OF "
475 			      "ALLOCATED FILE, SIZE SHOULD BE %ju",
476 			      (u_long)inumber, size, fixsize);
477 		else
478 			pfatal("INODE %lu: FILE SIZE %ju BEYOND END OF "
479 			      "ALLOCATED FILE, SIZE SHOULD BE %ju",
480 			      (u_long)inumber, size, fixsize);
481 		if (preen)
482 			printf(" (ADJUSTED)\n");
483 		else if (reply("ADJUST") == 0)
484 			return (1);
485 		if (bkgrdflag == 0) {
486 			ginode(inumber, &ip);
487 			DIP_SET(ip.i_dp, di_size, fixsize);
488 			inodirty(&ip);
489 			irelse(&ip);
490 		} else {
491 			cmd.value = idesc->id_number;
492 			cmd.size = fixsize;
493 			if (debug)
494 				printf("setsize ino %ju size set to %ju\n",
495 				    (uintmax_t)cmd.value, (uintmax_t)cmd.size);
496 			if (sysctl(setsize, MIBSIZE, 0, 0,
497 			    &cmd, sizeof cmd) == -1)
498 				rwerror("SET INODE SIZE", cmd.value);
499 		}
500 
501 	}
502 	return (1);
503 unknown:
504 	ginode(inumber, &ip);
505 	prtinode(&ip);
506 	inoinfo(inumber)->ino_state = USTATE;
507 	if (reply("CLEAR") == 1) {
508 		clearinode(ip.i_dp);
509 		inodirty(&ip);
510 	}
511 	irelse(&ip);
512 	return (1);
513 }
514 
515 int
pass1check(struct inodesc * idesc)516 pass1check(struct inodesc *idesc)
517 {
518 	int res = KEEPON;
519 	int anyout, nfrags;
520 	ufs2_daddr_t blkno = idesc->id_blkno;
521 	struct dups *dlp;
522 	struct dups *new;
523 
524 	if (idesc->id_type == SNAP) {
525 		if (blkno == BLK_NOCOPY)
526 			return (KEEPON);
527 		if (idesc->id_number == cursnapshot) {
528 			if (blkno == blkstofrags(&sblock, idesc->id_lbn))
529 				return (KEEPON);
530 			if (blkno == BLK_SNAP) {
531 				blkno = blkstofrags(&sblock, idesc->id_lbn);
532 				idesc->id_entryno -= idesc->id_numfrags;
533 			}
534 		} else {
535 			if (blkno == BLK_SNAP)
536 				return (KEEPON);
537 		}
538 	}
539 	if ((anyout = chkrange(blkno, idesc->id_numfrags)) != 0) {
540 		blkerror(idesc->id_number, "BAD", blkno);
541 		if (badblk++ >= MAXBAD) {
542 			pwarn("EXCESSIVE BAD BLKS I=%lu",
543 			    (u_long)idesc->id_number);
544 			if (preen)
545 				printf(" (SKIPPING)\n");
546 			else if (reply("CONTINUE") == 0) {
547 				ckfini(0);
548 				exit(EEXIT);
549 			}
550 			rerun = 1;
551 			return (STOP);
552 		}
553 	}
554 	for (nfrags = idesc->id_numfrags; nfrags > 0; blkno++, nfrags--) {
555 		if (anyout && chkrange(blkno, 1)) {
556 			res = SKIP;
557 		} else if (!testbmap(blkno)) {
558 			n_blks++;
559 			setbmap(blkno);
560 		} else {
561 			blkerror(idesc->id_number, "DUP", blkno);
562 			if (dupblk++ >= MAXDUP) {
563 				pwarn("EXCESSIVE DUP BLKS I=%lu",
564 					(u_long)idesc->id_number);
565 				if (preen)
566 					printf(" (SKIPPING)\n");
567 				else if (reply("CONTINUE") == 0) {
568 					ckfini(0);
569 					exit(EEXIT);
570 				}
571 				rerun = 1;
572 				return (STOP);
573 			}
574 			new = (struct dups *)Malloc(sizeof(struct dups));
575 			if (new == NULL) {
576 				pfatal("DUP TABLE OVERFLOW.");
577 				if (reply("CONTINUE") == 0) {
578 					ckfini(0);
579 					exit(EEXIT);
580 				}
581 				rerun = 1;
582 				return (STOP);
583 			}
584 			new->dup = blkno;
585 			if (muldup == NULL) {
586 				duplist = muldup = new;
587 				new->next = NULL;
588 			} else {
589 				new->next = muldup->next;
590 				muldup->next = new;
591 			}
592 			for (dlp = duplist; dlp != muldup; dlp = dlp->next)
593 				if (dlp->dup == blkno)
594 					break;
595 			if (dlp == muldup && dlp->dup != blkno)
596 				muldup = new;
597 		}
598 		/*
599 		 * count the number of blocks found in id_entryno
600 		 */
601 		idesc->id_entryno++;
602 	}
603 	if (idesc->id_level == 0 && idesc->id_lballoc < idesc->id_lbn)
604 		idesc->id_lballoc = idesc->id_lbn;
605 	return (res);
606 }
607