freebsd-dev/sbin/fsck_ffs/setup.c
Kirk McKusick 038c170fc2 Properly recover from superblock check-hash failures. Specifically,
report the check-hash failure and offer to search for and use
alternate superblocks.  Prior to this fix fsck_ffs would simply
report the check-hash failure and exit.

Reported by:  Julian H. Stacey <jhs@berklix.com>
Tested by:    Peter Holm
Sponsored by: Netflix
2018-11-25 18:09:39 +00:00

550 lines
16 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1980, 1986, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
#ifndef lint
static const char sccsid[] = "@(#)setup.c 8.10 (Berkeley) 5/9/95";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/disk.h>
#include <sys/stat.h>
#define FSTYPENAMES
#include <sys/disklabel.h>
#include <sys/file.h>
#include <sys/sysctl.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <stdint.h>
#include <string.h>
#include <libufs.h>
#include "fsck.h"
struct uufsd disk;
struct bufarea asblk;
#define altsblock (*asblk.b_un.b_fs)
#define POWEROF2(num) (((num) & ((num) - 1)) == 0)
static int calcsb(char *dev, int devfd, struct fs *fs);
static void saverecovery(int readfd, int writefd);
static int chkrecovery(int devfd);
/*
* Read in a superblock finding an alternate if necessary.
* Return 1 if successful, 0 if unsuccessful, -1 if file system
* is already clean (ckclean and preen mode only).
*/
int
setup(char *dev)
{
long cg, asked, i, j;
long bmapsize;
struct stat statb;
struct fs proto;
size_t size;
havesb = 0;
fswritefd = -1;
cursnapshot = 0;
if (stat(dev, &statb) < 0) {
printf("Can't stat %s: %s\n", dev, strerror(errno));
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
return (0);
}
if ((statb.st_mode & S_IFMT) != S_IFCHR &&
(statb.st_mode & S_IFMT) != S_IFBLK) {
if (bkgrdflag != 0 && (statb.st_flags & SF_SNAPSHOT) == 0) {
unlink(snapname);
printf("background fsck lacks a snapshot\n");
exit(EEXIT);
}
if ((statb.st_flags & SF_SNAPSHOT) != 0 && cvtlevel == 0) {
cursnapshot = statb.st_ino;
} else {
if (cvtlevel == 0 ||
(statb.st_flags & SF_SNAPSHOT) == 0) {
if (preen && bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
pfatal("%s is not a disk device", dev);
if (reply("CONTINUE") == 0) {
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
return (0);
}
} else {
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
pfatal("cannot convert a snapshot");
exit(EEXIT);
}
}
}
if ((fsreadfd = open(dev, O_RDONLY)) < 0 ||
ufs_disk_fillout_blank(&disk, dev) < 0) {
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
printf("Can't open %s: %s\n", dev, strerror(errno));
return (0);
}
if (bkgrdflag) {
unlink(snapname);
size = MIBSIZE;
if (sysctlnametomib("vfs.ffs.adjrefcnt", adjrefcnt, &size) < 0||
sysctlnametomib("vfs.ffs.adjblkcnt", adjblkcnt, &size) < 0||
sysctlnametomib("vfs.ffs.freefiles", freefiles, &size) < 0||
sysctlnametomib("vfs.ffs.freedirs", freedirs, &size) < 0 ||
sysctlnametomib("vfs.ffs.freeblks", freeblks, &size) < 0) {
pfatal("kernel lacks background fsck support\n");
exit(EEXIT);
}
/*
* When kernel is lack of runtime bgfsck superblock summary
* adjustment functionality, it does not mean we can not
* continue, as old kernels will recompute the summary at
* mount time. However, it will be an unexpected softupdates
* inconsistency if it turns out that the summary is still
* incorrect. Set a flag so subsequent operation can know
* this.
*/
bkgrdsumadj = 1;
if (sysctlnametomib("vfs.ffs.adjndir", adjndir, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnbfree", adjnbfree, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnifree", adjnifree, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnffree", adjnffree, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnumclusters", adjnumclusters, &size) < 0) {
bkgrdsumadj = 0;
pwarn("kernel lacks runtime superblock summary adjustment support");
}
cmd.version = FFS_CMD_VERSION;
cmd.handle = fsreadfd;
fswritefd = -1;
}
if (preen == 0)
printf("** %s", dev);
if (bkgrdflag == 0 &&
(nflag || ufs_disk_write(&disk) < 0 ||
(fswritefd = dup(disk.d_fd)) < 0)) {
fswritefd = -1;
if (preen)
pfatal("NO WRITE ACCESS");
printf(" (NO WRITE)");
}
if (preen == 0)
printf("\n");
/*
* Read in the superblock, looking for alternates if necessary
*/
if (readsb(1) == 0) {
skipclean = 0;
if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0)
return(0);
if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
return (0);
for (cg = 0; cg < proto.fs_ncg; cg++) {
bflag = fsbtodb(&proto, cgsblock(&proto, cg));
if (readsb(0) != 0)
break;
}
if (cg >= proto.fs_ncg) {
printf("%s %s\n%s %s\n%s %s\n",
"SEARCH FOR ALTERNATE SUPER-BLOCK",
"FAILED. YOU MUST USE THE",
"-b OPTION TO FSCK TO SPECIFY THE",
"LOCATION OF AN ALTERNATE",
"SUPER-BLOCK TO SUPPLY NEEDED",
"INFORMATION; SEE fsck_ffs(8).");
bflag = 0;
return(0);
}
pwarn("USING ALTERNATE SUPERBLOCK AT %jd\n", bflag);
bflag = 0;
}
if (skipclean && ckclean && sblock.fs_clean) {
pwarn("FILE SYSTEM CLEAN; SKIPPING CHECKS\n");
return (-1);
}
maxfsblock = sblock.fs_size;
maxino = sblock.fs_ncg * sblock.fs_ipg;
/*
* Check and potentially fix certain fields in the super block.
*/
if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
if (reply("SET TO DEFAULT") == 1) {
sblock.fs_optim = FS_OPTTIME;
sbdirty();
}
}
if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
sblock.fs_minfree);
if (reply("SET TO DEFAULT") == 1) {
sblock.fs_minfree = 10;
sbdirty();
}
}
if (sblock.fs_magic == FS_UFS1_MAGIC &&
sblock.fs_old_inodefmt < FS_44INODEFMT) {
pwarn("Format of file system is too old.\n");
pwarn("Must update to modern format using a version of fsck\n");
pfatal("from before 2002 with the command ``fsck -c 2''\n");
exit(EEXIT);
}
if (asblk.b_dirty && !bflag) {
memmove(&altsblock, &sblock, (size_t)sblock.fs_sbsize);
flush(fswritefd, &asblk);
}
if (preen == 0 && yflag == 0 && sblock.fs_magic == FS_UFS2_MAGIC &&
fswritefd != -1 && chkrecovery(fsreadfd) == 0 &&
reply("SAVE DATA TO FIND ALTERNATE SUPERBLOCKS") != 0)
saverecovery(fsreadfd, fswritefd);
/*
* read in the summary info.
*/
asked = 0;
sblock.fs_csp = Calloc(1, sblock.fs_cssize);
if (sblock.fs_csp == NULL) {
printf("cannot alloc %u bytes for cg summary info\n",
(unsigned)sblock.fs_cssize);
goto badsb;
}
for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
size = MIN(sblock.fs_cssize - i, sblock.fs_bsize);
readcnt[sblk.b_type]++;
if (blread(fsreadfd, (char *)sblock.fs_csp + i,
fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
size) != 0 && !asked) {
pfatal("BAD SUMMARY INFORMATION");
if (reply("CONTINUE") == 0) {
ckfini(0);
exit(EEXIT);
}
asked++;
}
}
/*
* allocate and initialize the necessary maps
*/
bmapsize = roundup(howmany(maxfsblock, CHAR_BIT), sizeof(short));
blockmap = Calloc((unsigned)bmapsize, sizeof (char));
if (blockmap == NULL) {
printf("cannot alloc %u bytes for blockmap\n",
(unsigned)bmapsize);
goto badsb;
}
inostathead = Calloc(sblock.fs_ncg, sizeof(struct inostatlist));
if (inostathead == NULL) {
printf("cannot alloc %u bytes for inostathead\n",
(unsigned)(sizeof(struct inostatlist) * (sblock.fs_ncg)));
goto badsb;
}
numdirs = MAX(sblock.fs_cstotal.cs_ndir, 128);
dirhash = numdirs;
inplast = 0;
listmax = numdirs + 10;
inpsort = (struct inoinfo **)Calloc(listmax, sizeof(struct inoinfo *));
inphead = (struct inoinfo **)Calloc(numdirs, sizeof(struct inoinfo *));
if (inpsort == NULL || inphead == NULL) {
printf("cannot alloc %ju bytes for inphead\n",
(uintmax_t)numdirs * sizeof(struct inoinfo *));
goto badsb;
}
bufinit();
if (sblock.fs_flags & FS_DOSOFTDEP)
usedsoftdep = 1;
else
usedsoftdep = 0;
return (1);
badsb:
ckfini(0);
return (0);
}
/*
* Read in the super block and its summary info.
*/
int
readsb(int listerr)
{
off_t super;
int bad, ret;
struct fs *fs;
super = bflag ? bflag * dev_bsize : -1;
readcnt[sblk.b_type]++;
if ((ret = sbget(fsreadfd, &fs, super)) != 0) {
switch (ret) {
case EINVAL:
/* Superblock check-hash failed */
return (0);
case ENOENT:
if (bflag)
fprintf(stderr, "%jd is not a file system "
"superblock\n", super / dev_bsize);
else
fprintf(stderr, "Cannot find file system "
"superblock\n");
return (0);
case EIO:
default:
fprintf(stderr, "I/O error reading %jd\n",
super / dev_bsize);
return (0);
}
}
memcpy(&sblock, fs, fs->fs_sbsize);
free(fs);
/*
* Compute block size that the file system is based on,
* according to fsbtodb, and adjust superblock block number
* so we can tell if this is an alternate later.
*/
dev_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
sblk.b_bno = sblock.fs_sblockactualloc / dev_bsize;
sblk.b_size = SBLOCKSIZE;
/*
* Compare all fields that should not differ in alternate super block.
* When an alternate super-block is specified this check is skipped.
*/
if (bflag)
goto out;
getblk(&asblk, cgsblock(&sblock, sblock.fs_ncg - 1), sblock.fs_sbsize);
if (asblk.b_errs)
return (0);
bad = 0;
#define CHK(x, y) \
if (altsblock.x != sblock.x) { \
bad++; \
if (listerr && debug) \
printf("SUPER BLOCK VS ALTERNATE MISMATCH %s: " y " vs " y "\n", \
#x, (intmax_t)sblock.x, (intmax_t)altsblock.x); \
}
CHK(fs_sblkno, "%jd");
CHK(fs_cblkno, "%jd");
CHK(fs_iblkno, "%jd");
CHK(fs_dblkno, "%jd");
CHK(fs_ncg, "%jd");
CHK(fs_bsize, "%jd");
CHK(fs_fsize, "%jd");
CHK(fs_frag, "%jd");
CHK(fs_bmask, "%#jx");
CHK(fs_fmask, "%#jx");
CHK(fs_bshift, "%jd");
CHK(fs_fshift, "%jd");
CHK(fs_fragshift, "%jd");
CHK(fs_fsbtodb, "%jd");
CHK(fs_sbsize, "%jd");
CHK(fs_nindir, "%jd");
CHK(fs_inopb, "%jd");
CHK(fs_cssize, "%jd");
CHK(fs_ipg, "%jd");
CHK(fs_fpg, "%jd");
CHK(fs_magic, "%#jx");
#undef CHK
if (bad) {
if (listerr == 0)
return (0);
if (preen)
printf("%s: ", cdevname);
printf(
"VALUES IN SUPER BLOCK LSB=%jd DISAGREE WITH THOSE IN\n"
"LAST ALTERNATE LSB=%jd\n",
sblk.b_bno, asblk.b_bno);
if (reply("IGNORE ALTERNATE SUPER BLOCK") == 0)
return (0);
}
out:
/*
* If not yet done, update UFS1 superblock with new wider fields.
*/
if (sblock.fs_magic == FS_UFS1_MAGIC &&
sblock.fs_maxbsize != sblock.fs_bsize) {
sblock.fs_maxbsize = sblock.fs_bsize;
sblock.fs_time = sblock.fs_old_time;
sblock.fs_size = sblock.fs_old_size;
sblock.fs_dsize = sblock.fs_old_dsize;
sblock.fs_csaddr = sblock.fs_old_csaddr;
sblock.fs_cstotal.cs_ndir = sblock.fs_old_cstotal.cs_ndir;
sblock.fs_cstotal.cs_nbfree = sblock.fs_old_cstotal.cs_nbfree;
sblock.fs_cstotal.cs_nifree = sblock.fs_old_cstotal.cs_nifree;
sblock.fs_cstotal.cs_nffree = sblock.fs_old_cstotal.cs_nffree;
}
havesb = 1;
return (1);
}
void
sblock_init(void)
{
fswritefd = -1;
fsmodified = 0;
lfdir = 0;
initbarea(&sblk, BT_SUPERBLK);
initbarea(&asblk, BT_SUPERBLK);
sblk.b_un.b_buf = Malloc(SBLOCKSIZE);
asblk.b_un.b_buf = Malloc(SBLOCKSIZE);
if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL)
errx(EEXIT, "cannot allocate space for superblock");
dev_bsize = secsize = DEV_BSIZE;
}
/*
* Calculate a prototype superblock based on information in the boot area.
* When done the cgsblock macro can be calculated and the fs_ncg field
* can be used. Do NOT attempt to use other macros without verifying that
* their needed information is available!
*/
static int
calcsb(char *dev, int devfd, struct fs *fs)
{
struct fsrecovery *fsr;
char *fsrbuf;
u_int secsize;
/*
* We need fragments-per-group and the partition-size.
*
* Newfs stores these details at the end of the boot block area
* at the start of the filesystem partition. If they have been
* overwritten by a boot block, we fail. But usually they are
* there and we can use them.
*/
if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1)
return (0);
fsrbuf = Malloc(secsize);
if (fsrbuf == NULL)
errx(EEXIT, "calcsb: cannot allocate recovery buffer");
if (blread(devfd, fsrbuf,
(SBLOCK_UFS2 - secsize) / dev_bsize, secsize) != 0)
return (0);
fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
if (fsr->fsr_magic != FS_UFS2_MAGIC)
return (0);
memset(fs, 0, sizeof(struct fs));
fs->fs_fpg = fsr->fsr_fpg;
fs->fs_fsbtodb = fsr->fsr_fsbtodb;
fs->fs_sblkno = fsr->fsr_sblkno;
fs->fs_magic = fsr->fsr_magic;
fs->fs_ncg = fsr->fsr_ncg;
free(fsrbuf);
return (1);
}
/*
* Check to see if recovery information exists.
* Return 1 if it exists or cannot be created.
* Return 0 if it does not exist and can be created.
*/
static int
chkrecovery(int devfd)
{
struct fsrecovery *fsr;
char *fsrbuf;
u_int secsize;
/*
* Could not determine if backup material exists, so do not
* offer to create it.
*/
if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1 ||
(fsrbuf = Malloc(secsize)) == NULL ||
blread(devfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
secsize) != 0)
return (1);
/*
* Recovery material has already been created, so do not
* need to create it again.
*/
fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
if (fsr->fsr_magic == FS_UFS2_MAGIC) {
free(fsrbuf);
return (1);
}
/*
* Recovery material has not been created and can be if desired.
*/
free(fsrbuf);
return (0);
}
/*
* Read the last sector of the boot block, replace the last
* 20 bytes with the recovery information, then write it back.
* The recovery information only works for UFS2 filesystems.
*/
static void
saverecovery(int readfd, int writefd)
{
struct fsrecovery *fsr;
char *fsrbuf;
u_int secsize;
if (sblock.fs_magic != FS_UFS2_MAGIC ||
ioctl(readfd, DIOCGSECTORSIZE, &secsize) == -1 ||
(fsrbuf = Malloc(secsize)) == NULL ||
blread(readfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
secsize) != 0) {
printf("RECOVERY DATA COULD NOT BE CREATED\n");
return;
}
fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
fsr->fsr_magic = sblock.fs_magic;
fsr->fsr_fpg = sblock.fs_fpg;
fsr->fsr_fsbtodb = sblock.fs_fsbtodb;
fsr->fsr_sblkno = sblock.fs_sblkno;
fsr->fsr_ncg = sblock.fs_ncg;
blwrite(writefd, fsrbuf, (SBLOCK_UFS2 - secsize) / secsize, secsize);
free(fsrbuf);
}