• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * e2undo.c - Replay an undo log onto an ext2/3/4 filesystem
3  *
4  * Copyright IBM Corporation, 2007
5  * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
6  *
7  * %Begin-Header%
8  * This file may be redistributed under the terms of the GNU Public
9  * License.
10  * %End-Header%
11  */
12 
13 #include "config.h"
14 #include <stdio.h>
15 #include <stdlib.h>
16 #ifdef HAVE_GETOPT_H
17 #include <getopt.h>
18 #endif
19 #include <fcntl.h>
20 #if HAVE_ERRNO_H
21 #include <errno.h>
22 #endif
23 #include <unistd.h>
24 #include <libgen.h>
25 #include "ext2fs/ext2fs.h"
26 #include "support/nls-enable.h"
27 
28 #undef DEBUG
29 
30 #ifdef DEBUG
31 # define dbg_printf(f, a...)  do {printf(f, ## a); fflush(stdout); } while (0)
32 #else
33 # define dbg_printf(f, a...)
34 #endif
35 
36 /*
37  * Undo file format: The file is cut up into undo_header.block_size blocks.
38  * The first block contains the header.
39  * The second block contains the superblock.
40  * There is then a repeating series of blocks as follows:
41  *   A key block, which contains undo_keys to map the following data blocks.
42  *   Data blocks
43  * (Note that there are pointers to the first key block and the sb, so this
44  * order isn't strictly necessary.)
45  */
46 #define E2UNDO_MAGIC "E2UNDO02"
47 #define KEYBLOCK_MAGIC 0xCADECADE
48 
49 #define E2UNDO_STATE_FINISHED	0x1	/* undo file is complete */
50 
51 #define E2UNDO_MIN_BLOCK_SIZE	1024	/* undo blocks are no less than 1KB */
52 #define E2UNDO_MAX_BLOCK_SIZE	1048576	/* undo blocks are no more than 1MB */
53 
54 struct undo_header {
55 	char magic[8];		/* "E2UNDO02" */
56 	__le64 num_keys;	/* how many keys? */
57 	__le64 super_offset;	/* where in the file is the superblock copy? */
58 	__le64 key_offset;	/* where do the key/data block chunks start? */
59 	__le32 block_size;	/* block size of the undo file */
60 	__le32 fs_block_size;	/* block size of the target device */
61 	__le32 sb_crc;		/* crc32c of the superblock */
62 	__le32 state;		/* e2undo state flags */
63 	__le32 f_compat;	/* compatible features (none so far) */
64 	__le32 f_incompat;	/* incompatible features (none so far) */
65 	__le32 f_rocompat;	/* ro compatible features (none so far) */
66 	__le32 pad32;		/* padding for fs_offset */
67 	__le64 fs_offset;	/* filesystem offset */
68 	__u8 padding[436];	/* padding */
69 	__le32 header_crc;	/* crc32c of the header (but not this field) */
70 };
71 
72 #define E2UNDO_MAX_EXTENT_BLOCKS	512	/* max extent size, in blocks */
73 
74 struct undo_key {
75 	__le64 fsblk;		/* where in the fs does the block go */
76 	__le32 blk_crc;		/* crc32c of the block */
77 	__le32 size;		/* how many bytes in this block? */
78 };
79 
80 struct undo_key_block {
81 	__le32 magic;		/* KEYBLOCK_MAGIC number */
82 	__le32 crc;		/* block checksum */
83 	__le64 reserved;	/* zero */
84 
85 	struct undo_key keys[0];	/* keys, which come immediately after */
86 };
87 
88 struct undo_key_info {
89 	blk64_t fsblk;
90 	blk64_t fileblk;
91 	__u32 blk_crc;
92 	unsigned int size;
93 };
94 
95 struct undo_context {
96 	struct undo_header hdr;
97 	io_channel undo_file;
98 	unsigned int blocksize, fs_blocksize;
99 	blk64_t super_block;
100 	size_t num_keys;
101 	struct undo_key_info *keys;
102 };
103 #define KEYS_PER_BLOCK(d) (((d)->blocksize / sizeof(struct undo_key)) - 1)
104 
105 #define E2UNDO_FEATURE_COMPAT_FS_OFFSET 0x1	/* the filesystem offset */
106 
e2undo_has_feature_fs_offset(struct undo_header * header)107 static inline int e2undo_has_feature_fs_offset(struct undo_header *header) {
108 	return ext2fs_le32_to_cpu(header->f_compat) &
109 		E2UNDO_FEATURE_COMPAT_FS_OFFSET;
110 }
111 
112 static char *prg_name;
113 static char *undo_file;
114 
usage(void)115 static void usage(void)
116 {
117 	fprintf(stderr,
118 		_("Usage: %s [-f] [-h] [-n] [-v] <transaction file> <filesystem>\n"), prg_name);
119 	exit(1);
120 }
121 
dump_header(struct undo_header * hdr)122 static void dump_header(struct undo_header *hdr)
123 {
124 	printf("nr keys:\t%llu\n", ext2fs_le64_to_cpu(hdr->num_keys));
125 	printf("super block:\t%llu\n", ext2fs_le64_to_cpu(hdr->super_offset));
126 	printf("key block:\t%llu\n", ext2fs_le64_to_cpu(hdr->key_offset));
127 	printf("block size:\t%u\n", ext2fs_le32_to_cpu(hdr->block_size));
128 	printf("fs block size:\t%u\n", ext2fs_le32_to_cpu(hdr->fs_block_size));
129 	printf("super crc:\t0x%x\n", ext2fs_le32_to_cpu(hdr->sb_crc));
130 	printf("state:\t\t0x%x\n", ext2fs_le32_to_cpu(hdr->state));
131 	printf("compat:\t\t0x%x\n", ext2fs_le32_to_cpu(hdr->f_compat));
132 	printf("incompat:\t0x%x\n", ext2fs_le32_to_cpu(hdr->f_incompat));
133 	printf("rocompat:\t0x%x\n", ext2fs_le32_to_cpu(hdr->f_rocompat));
134 	if (e2undo_has_feature_fs_offset(hdr))
135 		printf("fs offset:\t%llu\n", ext2fs_le64_to_cpu(hdr->fs_offset));
136 	printf("header crc:\t0x%x\n", ext2fs_le32_to_cpu(hdr->header_crc));
137 }
138 
print_undo_mismatch(struct ext2_super_block * fs_super,struct ext2_super_block * undo_super)139 static void print_undo_mismatch(struct ext2_super_block *fs_super,
140 				struct ext2_super_block *undo_super)
141 {
142 	printf("%s",
143 	       _("The file system superblock doesn't match the undo file.\n"));
144 	if (memcmp(fs_super->s_uuid, undo_super->s_uuid,
145 		   sizeof(fs_super->s_uuid)))
146 		printf("%s", _("UUID does not match.\n"));
147 	if (fs_super->s_mtime != undo_super->s_mtime)
148 		printf("%s", _("Last mount time does not match.\n"));
149 	if (fs_super->s_wtime != undo_super->s_wtime)
150 		printf("%s", _("Last write time does not match.\n"));
151 	if (fs_super->s_kbytes_written != undo_super->s_kbytes_written)
152 		printf("%s", _("Lifetime write counter does not match.\n"));
153 }
154 
check_filesystem(struct undo_context * ctx,io_channel channel)155 static int check_filesystem(struct undo_context *ctx, io_channel channel)
156 {
157 	struct ext2_super_block super, *sb;
158 	char *buf;
159 	__u32 sb_crc;
160 	errcode_t retval;
161 
162 	io_channel_set_blksize(channel, SUPERBLOCK_OFFSET);
163 	retval = io_channel_read_blk64(channel, 1, -SUPERBLOCK_SIZE, &super);
164 	if (retval) {
165 		com_err(prg_name, retval,
166 			"%s", _("while reading filesystem superblock."));
167 		return retval;
168 	}
169 
170 	/*
171 	 * Compare the FS and the undo file superblock so that we can't apply
172 	 * e2undo "patches" out of order.
173 	 */
174 	retval = ext2fs_get_mem(ctx->blocksize, &buf);
175 	if (retval) {
176 		com_err(prg_name, retval, "%s", _("while allocating memory"));
177 		return retval;
178 	}
179 	retval = io_channel_read_blk64(ctx->undo_file, ctx->super_block,
180 				       -SUPERBLOCK_SIZE, buf);
181 	if (retval) {
182 		com_err(prg_name, retval, "%s", _("while fetching superblock"));
183 		goto out;
184 	}
185 	sb = (struct ext2_super_block *)buf;
186 	sb->s_magic = ~sb->s_magic;
187 	if (memcmp(&super, buf, sizeof(super))) {
188 		print_undo_mismatch(&super, (struct ext2_super_block *)buf);
189 		retval = -1;
190 		goto out;
191 	}
192 	sb_crc = ext2fs_crc32c_le(~0, (unsigned char *)buf, SUPERBLOCK_SIZE);
193 	if (ext2fs_le32_to_cpu(ctx->hdr.sb_crc) != sb_crc) {
194 		fprintf(stderr,
195 			_("Undo file superblock checksum doesn't match.\n"));
196 		retval = -1;
197 		goto out;
198 	}
199 
200 out:
201 	ext2fs_free_mem(&buf);
202 	return retval;
203 }
204 
key_compare(const void * a,const void * b)205 static int key_compare(const void *a, const void *b)
206 {
207 	const struct undo_key_info *ka, *kb;
208 
209 	ka = a;
210 	kb = b;
211 	return ka->fsblk - kb->fsblk;
212 }
213 
e2undo_setup_tdb(const char * name,io_manager * io_ptr)214 static int e2undo_setup_tdb(const char *name, io_manager *io_ptr)
215 {
216 	errcode_t retval = 0;
217 	const char *tdb_dir;
218 	char *tdb_file = NULL;
219 	char *dev_name, *tmp_name;
220 
221 	/* (re)open a specific undo file */
222 	if (undo_file && undo_file[0] != 0) {
223 		retval = set_undo_io_backing_manager(*io_ptr);
224 		if (retval)
225 			goto err;
226 		*io_ptr = undo_io_manager;
227 		retval = set_undo_io_backup_file(undo_file);
228 		if (retval)
229 			goto err;
230 		printf(_("Overwriting existing filesystem; this can be undone "
231 			 "using the command:\n"
232 			 "    e2undo %s %s\n\n"),
233 			 undo_file, name);
234 		return retval;
235 	}
236 
237 	/*
238 	 * Configuration via a conf file would be
239 	 * nice
240 	 */
241 	tdb_dir = getenv("E2FSPROGS_UNDO_DIR");
242 	if (!tdb_dir)
243 		tdb_dir = "/var/lib/e2fsprogs";
244 
245 	if (!strcmp(tdb_dir, "none") || (tdb_dir[0] == 0) ||
246 	    access(tdb_dir, W_OK))
247 		return 0;
248 
249 	tmp_name = strdup(name);
250 	if (!tmp_name)
251 		goto errout;
252 	dev_name = basename(tmp_name);
253 	tdb_file = malloc(strlen(tdb_dir) + 8 + strlen(dev_name) + 7 + 1);
254 	if (!tdb_file) {
255 		free(tmp_name);
256 		goto errout;
257 	}
258 	sprintf(tdb_file, "%s/e2undo-%s.e2undo", tdb_dir, dev_name);
259 	free(tmp_name);
260 
261 	if ((unlink(tdb_file) < 0) && (errno != ENOENT)) {
262 		retval = errno;
263 		com_err(prg_name, retval,
264 			_("while trying to delete %s"), tdb_file);
265 		goto errout;
266 	}
267 
268 	retval = set_undo_io_backing_manager(*io_ptr);
269 	if (retval)
270 		goto errout;
271 	*io_ptr = undo_io_manager;
272 	retval = set_undo_io_backup_file(tdb_file);
273 	if (retval)
274 		goto errout;
275 	printf(_("Overwriting existing filesystem; this can be undone "
276 		 "using the command:\n"
277 		 "    e2undo %s %s\n\n"),
278 		 tdb_file, name);
279 
280 	free(tdb_file);
281 	return 0;
282 errout:
283 	free(tdb_file);
284 err:
285 	com_err(prg_name, retval, "while trying to setup undo file\n");
286 	return retval;
287 }
288 
main(int argc,char * argv[])289 int main(int argc, char *argv[])
290 {
291 	int c, force = 0, dry_run = 0, verbose = 0, dump = 0;
292 	io_channel channel;
293 	errcode_t retval;
294 	int mount_flags, csum_error = 0, io_error = 0;
295 	size_t i, keys_per_block;
296 	char *device_name, *tdb_file;
297 	io_manager manager = unix_io_manager;
298 	struct undo_context undo_ctx;
299 	char *buf;
300 	struct undo_key_block *keyb;
301 	struct undo_key *dkey;
302 	struct undo_key_info *ikey;
303 	__u32 key_crc, blk_crc, hdr_crc;
304 	blk64_t lblk;
305 	ext2_filsys fs;
306 	__u64 offset = 0;
307 	char opt_offset_string[40] = { 0 };
308 
309 #ifdef ENABLE_NLS
310 	setlocale(LC_MESSAGES, "");
311 	setlocale(LC_CTYPE, "");
312 	bindtextdomain(NLS_CAT_NAME, LOCALEDIR);
313 	textdomain(NLS_CAT_NAME);
314 	set_com_err_gettext(gettext);
315 #endif
316 	add_error_table(&et_ext2_error_table);
317 
318 	prg_name = argv[0];
319 	while ((c = getopt(argc, argv, "fhno:vz:")) != EOF) {
320 		switch (c) {
321 		case 'f':
322 			force = 1;
323 			break;
324 		case 'h':
325 			dump = 1;
326 			break;
327 		case 'n':
328 			dry_run = 1;
329 			break;
330 		case 'o':
331 			offset = strtoull(optarg, &buf, 0);
332 			if (*buf) {
333 				com_err(prg_name, 0,
334 						_("illegal offset - %s"), optarg);
335 				exit(1);
336 			}
337 			/* used to indicate that an offset was specified */
338 			opt_offset_string[0] = 1;
339 			break;
340 		case 'v':
341 			verbose = 1;
342 			break;
343 		case 'z':
344 			undo_file = optarg;
345 			break;
346 		default:
347 			usage();
348 		}
349 	}
350 
351 	if (argc != optind + 2)
352 		usage();
353 
354 	tdb_file = argv[optind];
355 	device_name = argv[optind+1];
356 
357 	if (undo_file && strcmp(tdb_file, undo_file) == 0) {
358 		printf(_("Will not write to an undo file while replaying it.\n"));
359 		exit(1);
360 	}
361 
362 	/* Interpret the undo file */
363 	retval = manager->open(tdb_file, IO_FLAG_EXCLUSIVE,
364 			       &undo_ctx.undo_file);
365 	if (retval) {
366 		com_err(prg_name, errno,
367 				_("while opening undo file `%s'\n"), tdb_file);
368 		exit(1);
369 	}
370 	retval = io_channel_read_blk64(undo_ctx.undo_file, 0,
371 				       -(int)sizeof(undo_ctx.hdr),
372 				       &undo_ctx.hdr);
373 	if (retval) {
374 		com_err(prg_name, retval, _("while reading undo file"));
375 		exit(1);
376 	}
377 	if (memcmp(undo_ctx.hdr.magic, E2UNDO_MAGIC,
378 		    sizeof(undo_ctx.hdr.magic))) {
379 		fprintf(stderr, _("%s: Not an undo file.\n"), tdb_file);
380 		exit(1);
381 	}
382 	if (dump) {
383 		dump_header(&undo_ctx.hdr);
384 		exit(1);
385 	}
386 	hdr_crc = ext2fs_crc32c_le(~0, (unsigned char *)&undo_ctx.hdr,
387 				   sizeof(struct undo_header) -
388 				   sizeof(__u32));
389 	if (!force && ext2fs_le32_to_cpu(undo_ctx.hdr.header_crc) != hdr_crc) {
390 		fprintf(stderr, _("%s: Header checksum doesn't match.\n"),
391 			tdb_file);
392 		exit(1);
393 	}
394 	undo_ctx.blocksize = ext2fs_le32_to_cpu(undo_ctx.hdr.block_size);
395 	undo_ctx.fs_blocksize = ext2fs_le32_to_cpu(undo_ctx.hdr.fs_block_size);
396 	if (undo_ctx.blocksize == 0 || undo_ctx.fs_blocksize == 0) {
397 		fprintf(stderr, _("%s: Corrupt undo file header.\n"), tdb_file);
398 		exit(1);
399 	}
400 	if (!force && undo_ctx.blocksize > E2UNDO_MAX_BLOCK_SIZE) {
401 		fprintf(stderr, _("%s: Undo block size too large.\n"),
402 			tdb_file);
403 		exit(1);
404 	}
405 	if (!force && undo_ctx.blocksize < E2UNDO_MIN_BLOCK_SIZE) {
406 		fprintf(stderr, _("%s: Undo block size too small.\n"),
407 			tdb_file);
408 		exit(1);
409 	}
410 	undo_ctx.super_block = ext2fs_le64_to_cpu(undo_ctx.hdr.super_offset);
411 	undo_ctx.num_keys = ext2fs_le64_to_cpu(undo_ctx.hdr.num_keys);
412 	io_channel_set_blksize(undo_ctx.undo_file, undo_ctx.blocksize);
413 	/*
414 	 * Do not compare undo_ctx.hdr.f_compat with the available compatible
415 	 * features set, because a "missing" compatible feature should
416 	 * not cause any problems.
417 	 */
418 	if (!force && (undo_ctx.hdr.f_incompat || undo_ctx.hdr.f_rocompat)) {
419 		fprintf(stderr, _("%s: Unknown undo file feature set.\n"),
420 			tdb_file);
421 		exit(1);
422 	}
423 
424 	/* open the fs */
425 	retval = ext2fs_check_if_mounted(device_name, &mount_flags);
426 	if (retval) {
427 		com_err(prg_name, retval, _("Error while determining whether "
428 				"%s is mounted."), device_name);
429 		exit(1);
430 	}
431 
432 	if (mount_flags & EXT2_MF_MOUNTED) {
433 		com_err(prg_name, retval, "%s", _("e2undo should only be run "
434 						"on unmounted filesystems"));
435 		exit(1);
436 	}
437 
438 	if (undo_file) {
439 		retval = e2undo_setup_tdb(device_name, &manager);
440 		if (retval)
441 			exit(1);
442 	}
443 
444 	retval = manager->open(device_name,
445 			       IO_FLAG_EXCLUSIVE | (dry_run ? 0 : IO_FLAG_RW),
446 			       &channel);
447 	if (retval) {
448 		com_err(prg_name, retval,
449 				_("while opening `%s'"), device_name);
450 		exit(1);
451 	}
452 
453 	if (*opt_offset_string || e2undo_has_feature_fs_offset(&undo_ctx.hdr)) {
454 		if (!*opt_offset_string)
455 			offset = ext2fs_le64_to_cpu(undo_ctx.hdr.fs_offset);
456 		retval = snprintf(opt_offset_string, sizeof(opt_offset_string),
457 						  "offset=%llu", offset);
458 		if ((size_t) retval >= sizeof(opt_offset_string)) {
459 			/* should not happen... */
460 			com_err(prg_name, 0, _("specified offset is too large"));
461 			exit(1);
462 		}
463 		io_channel_set_options(channel, opt_offset_string);
464 	}
465 
466 	if (!force && check_filesystem(&undo_ctx, channel))
467 		exit(1);
468 
469 	/* prepare to read keys */
470 	retval = ext2fs_get_mem(sizeof(struct undo_key_info) * undo_ctx.num_keys,
471 				&undo_ctx.keys);
472 	if (retval) {
473 		com_err(prg_name, retval, "%s", _("while allocating memory"));
474 		exit(1);
475 	}
476 	ikey = undo_ctx.keys;
477 	retval = ext2fs_get_mem(undo_ctx.blocksize, &keyb);
478 	if (retval) {
479 		com_err(prg_name, retval, "%s", _("while allocating memory"));
480 		exit(1);
481 	}
482 	retval = ext2fs_get_mem(E2UNDO_MAX_EXTENT_BLOCKS * undo_ctx.blocksize,
483 				&buf);
484 	if (retval) {
485 		com_err(prg_name, retval, "%s", _("while allocating memory"));
486 		exit(1);
487 	}
488 
489 	/* load keys */
490 	keys_per_block = KEYS_PER_BLOCK(&undo_ctx);
491 	lblk = ext2fs_le64_to_cpu(undo_ctx.hdr.key_offset);
492 	dbg_printf("nr_keys=%lu, kpb=%zu, blksz=%u\n",
493 		   undo_ctx.num_keys, keys_per_block, undo_ctx.blocksize);
494 	for (i = 0; i < undo_ctx.num_keys; i += keys_per_block) {
495 		size_t j, max_j;
496 		__le32 crc;
497 
498 		retval = io_channel_read_blk64(undo_ctx.undo_file,
499 					       lblk, 1, keyb);
500 		if (retval) {
501 			com_err(prg_name, retval, "%s", _("while reading keys"));
502 			if (force) {
503 				io_error = 1;
504 				undo_ctx.num_keys = i - 1;
505 				break;
506 			}
507 			exit(1);
508 		}
509 
510 		/* check keys */
511 		if (!force &&
512 		    ext2fs_le32_to_cpu(keyb->magic) != KEYBLOCK_MAGIC) {
513 			fprintf(stderr, _("%s: wrong key magic at %llu\n"),
514 				tdb_file, lblk);
515 			exit(1);
516 		}
517 		crc = keyb->crc;
518 		keyb->crc = 0;
519 		key_crc = ext2fs_crc32c_le(~0, (unsigned char *)keyb,
520 					   undo_ctx.blocksize);
521 		if (!force && ext2fs_le32_to_cpu(crc) != key_crc) {
522 			fprintf(stderr,
523 				_("%s: key block checksum error at %llu.\n"),
524 				tdb_file, lblk);
525 			exit(1);
526 		}
527 
528 		/* load keys from key block */
529 		lblk++;
530 		max_j = undo_ctx.num_keys - i;
531 		if (max_j > keys_per_block)
532 			max_j = keys_per_block;
533 		for (j = 0, dkey = keyb->keys;
534 		     j < max_j;
535 		     j++, ikey++, dkey++) {
536 			ikey->fsblk = ext2fs_le64_to_cpu(dkey->fsblk);
537 			ikey->fileblk = lblk;
538 			ikey->blk_crc = ext2fs_le32_to_cpu(dkey->blk_crc);
539 			ikey->size = ext2fs_le32_to_cpu(dkey->size);
540 			lblk += (ikey->size + undo_ctx.blocksize - 1) /
541 				undo_ctx.blocksize;
542 
543 			if (E2UNDO_MAX_EXTENT_BLOCKS * undo_ctx.blocksize <
544 			    ikey->size) {
545 				com_err(prg_name, retval,
546 					_("%s: block %llu is too long."),
547 					tdb_file, ikey->fsblk);
548 				exit(1);
549 			}
550 
551 			/* check each block's crc */
552 			retval = io_channel_read_blk64(undo_ctx.undo_file,
553 						       ikey->fileblk,
554 						       -(int)ikey->size,
555 						       buf);
556 			if (retval) {
557 				com_err(prg_name, retval,
558 					_("while fetching block %llu."),
559 					ikey->fileblk);
560 				if (!force)
561 					exit(1);
562 				io_error = 1;
563 				continue;
564 			}
565 
566 			blk_crc = ext2fs_crc32c_le(~0, (unsigned char *)buf,
567 						   ikey->size);
568 			if (blk_crc != ikey->blk_crc) {
569 				fprintf(stderr,
570 					_("checksum error in filesystem block "
571 					  "%llu (undo blk %llu)\n"),
572 					ikey->fsblk, ikey->fileblk);
573 				if (!force)
574 					exit(1);
575 				csum_error = 1;
576 			}
577 		}
578 	}
579 	ext2fs_free_mem(&keyb);
580 
581 	/* sort keys in fs block order */
582 	qsort(undo_ctx.keys, undo_ctx.num_keys, sizeof(struct undo_key_info),
583 	      key_compare);
584 
585 	/* replay */
586 	io_channel_set_blksize(channel, undo_ctx.fs_blocksize);
587 	for (i = 0, ikey = undo_ctx.keys; i < undo_ctx.num_keys; i++, ikey++) {
588 		retval = io_channel_read_blk64(undo_ctx.undo_file,
589 					       ikey->fileblk,
590 					       -(int)ikey->size,
591 					       buf);
592 		if (retval) {
593 			com_err(prg_name, retval,
594 				_("while fetching block %llu."),
595 				ikey->fileblk);
596 			io_error = 1;
597 			continue;
598 		}
599 
600 		if (verbose)
601 			printf("Replayed block of size %u from %llu to %llu\n",
602 				ikey->size, ikey->fileblk, ikey->fsblk);
603 		if (dry_run)
604 			continue;
605 		retval = io_channel_write_blk64(channel, ikey->fsblk,
606 						-(int)ikey->size, buf);
607 		if (retval) {
608 			com_err(prg_name, retval,
609 				_("while writing block %llu."), ikey->fsblk);
610 			io_error = 1;
611 		}
612 	}
613 
614 	if (csum_error)
615 		fprintf(stderr, _("Undo file corruption; run e2fsck NOW!\n"));
616 	if (io_error)
617 		fprintf(stderr, _("IO error during replay; run e2fsck NOW!\n"));
618 	if (!(ext2fs_le32_to_cpu(undo_ctx.hdr.state) & E2UNDO_STATE_FINISHED)) {
619 		force = 1;
620 		fprintf(stderr, _("Incomplete undo record; run e2fsck.\n"));
621 	}
622 	ext2fs_free_mem(&buf);
623 	ext2fs_free_mem(&undo_ctx.keys);
624 	io_channel_close(channel);
625 
626 	/* If there were problems, try to force a fsck */
627 	if (!dry_run && (force || csum_error || io_error)) {
628 		retval = ext2fs_open2(device_name, NULL,
629 				   EXT2_FLAG_RW | EXT2_FLAG_64BITS, 0, 0,
630 				   manager, &fs);
631 		if (retval)
632 			goto out;
633 		fs->super->s_state &= ~EXT2_VALID_FS;
634 		if (csum_error || io_error)
635 			fs->super->s_state |= EXT2_ERROR_FS;
636 		ext2fs_mark_super_dirty(fs);
637 		ext2fs_close_free(&fs);
638 	}
639 
640 out:
641 	io_channel_close(undo_ctx.undo_file);
642 
643 	return csum_error;
644 }
645