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

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

details:   https://anonhg.NetBSD.org/src/rev/708af774dc03
branches:  trunk
changeset: 559672:708af774dc03
user:      dsl <dsl%NetBSD.org@localhost>
date:      Sun Mar 21 19:13:59 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/badsect/badsect.c |  27 ++++++++++++++++++---------
 1 files changed, 18 insertions(+), 9 deletions(-)

diffs (63 lines):

diff -r f8514999527e -r 708af774dc03 sbin/badsect/badsect.c
--- a/sbin/badsect/badsect.c    Sun Mar 21 18:48:24 2004 +0000
+++ b/sbin/badsect/badsect.c    Sun Mar 21 19:13:59 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: badsect.c,v 1.25 2004/01/05 23:23:32 jmmv Exp $        */
+/*     $NetBSD: badsect.c,v 1.26 2004/03/21 19:13:59 dsl Exp $ */
 
 /*
  * Copyright (c) 1981, 1983, 1993
@@ -39,7 +39,7 @@
 #if 0
 static char sccsid[] = "@(#)badsect.c  8.2 (Berkeley) 5/4/95";
 #else
-__RCSID("$NetBSD: badsect.c,v 1.25 2004/01/05 23:23:32 jmmv Exp $");
+__RCSID("$NetBSD: badsect.c,v 1.26 2004/03/21 19:13:59 dsl Exp $");
 #endif
 #endif /* not lint */
 
@@ -151,28 +151,37 @@
 
        fs = &sblock;
 
-       for (i = 0; sblock_try[i] != -1; i++) {
+       for (i = 0; ; i++) {
+               if (sblock_try[i] == -1)
+                       errx(1, "%s: bad superblock", name);
                rdfs(sblock_try[i] / DEV_BSIZE, SBLOCKSIZE, (char *)fs);
                switch (fs->fs_magic) {
                case FS_UFS2_MAGIC:
                        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;
+                       ffs_sb_swap(fs, fs);
+                       break;
                default:
                        continue;
                }
+
+               /* Ensure we don't use 1st alternate if ffsv1 and bs=64k */
+               if (fs->fs_old_flags & FS_FLAGS_UPDATED) {
+                       if (fs->fs_sblockloc != sblock_try[i])
+                               continue;
+               } else {
+                       if (sblock_try[i] == SBLOCK_UFS2)
+                               continue;
+               }
+               break;
        }
-       errx(1, "%s: bad superblock", name);
-found:
-       if (needswap)
-               ffs_sb_swap(fs, fs);
 
        dev_bsize = fs->fs_fsize / fsbtodb(fs, 1);
        for (argc -= 2, argv += 2; argc > 0; argc--, argv++) {