[src/trunk]: src/sbin/clri When searching for the superblock, check that the ...

[dsl <dsl%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/61cb1696a197
branches:  trunk
changeset: 559673:61cb1696a197
user:      dsl <dsl%NetBSD.org@localhost>
date:      Sun Mar 21 19:35:23 2004 +0000

description:
When searching for the superblock, check that the fs_sblockloc field
matches the location we read it from to ensure we don't have one of the
alternate superblocks.
Fixes part of PR kern/24809

diffstat:

 sbin/clri/clri.c |  38 +++++++++++++++++++++++---------------
 1 files changed, 23 insertions(+), 15 deletions(-)

diffs (82 lines):

diff -r 708af774dc03 -r 61cb1696a197 sbin/clri/clri.c
--- a/sbin/clri/clri.c  Sun Mar 21 19:13:59 2004 +0000
+++ b/sbin/clri/clri.c  Sun Mar 21 19:35:23 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: clri.c,v 1.16 2003/08/07 10:04:12 agc Exp $    */
+/*     $NetBSD: clri.c,v 1.17 2004/03/21 19:35:23 dsl Exp $    */
 
 /*
  * Copyright (c) 1990, 1993
@@ -42,7 +42,7 @@
 #if 0
 static char sccsid[] = "@(#)clri.c     8.3 (Berkeley) 4/28/95";
 #else
-__RCSID("$NetBSD: clri.c,v 1.16 2003/08/07 10:04:12 agc Exp $");
+__RCSID("$NetBSD: clri.c,v 1.17 2004/03/21 19:35:23 dsl Exp $");
 #endif
 #endif /* not lint */
 
@@ -100,10 +100,11 @@
        /* get the superblock. */
        if ((fd = open(fs, O_RDWR, 0)) < 0)
                err(1, "%s", fs);
-       for (i = 0; i < sblock_try[i] != -1; i++) {
-               if (lseek(fd, sblock_try[i], SEEK_SET) < 0)
-                       err(1, "%s", fs);
-               if (read(fd, sblock, sizeof(sblock)) != sizeof(sblock))
+       for (i = 0;; i++) {
+               sblockloc = sblock_try[i];
+               if (sblockloc == -1)
+                       errx(1, "%s: can't find superblock", fs);
+               if (pread(fd, sblock, sizeof(sblock), sblockloc) != sizeof(sblock))
                        errx(1, "%s: can't read superblock", fs);
 
                sbp = (struct fs *)sblock;
@@ -112,21 +113,29 @@
                        is_ufs2 = 1;
                        /*FALLTHROUGH*/
                case FS_UFS1_MAGIC:
-                       goto found;
+                       break;
                case FS_UFS2_MAGIC_SWAPPED:
                        is_ufs2 = 1;
                        /*FALLTHROUGH*/
                case FS_UFS1_MAGIC_SWAPPED:
                        needswap = 1;
-                       goto found;
+                       break;
                default:
                        continue;
                }
-       }
-       errx(1, "%s: can't find superblock", fs);
 
-found:
-       sblockloc = sblock_try[i];
+               /* check we haven't found an alternate */
+               if (sbp->fs_old_flags & FS_FLAGS_UPDATED) {
+                       if (sblockloc != ufs_rw64(sbp->fs_sblockloc, needswap))
+                               continue;
+               } else {
+                       if (sblockloc == SBLOCK_UFS2)
+                               continue;
+               }
+
+               break;
+       }
+
        /* check that inode numbers are valid */
        imax = ufs_rw32(sbp->fs_ncg, needswap) *
                ufs_rw32(sbp->fs_ipg, needswap);
@@ -135,9 +144,8 @@
                        errx(1, "%s is not a valid inode number", argv[i]);
 
        /* delete clean flag in the superblok */
-       sbp->fs_clean = ufs_rw32(
-                                               ufs_rw32(sbp->fs_clean, needswap) << 1,
-                                               needswap);
+       sbp->fs_clean = ufs_rw32(ufs_rw32(sbp->fs_clean, needswap) << 1,
+                               needswap);
        if (lseek(fd, sblockloc, SEEK_SET) < 0)
                err(1, "%s", fs);
        if (write(fd, sblock, sizeof(sblock)) != sizeof(sblock))