[src/trunk]: src/sbin/restore If we hit an unknown header type (likely to be ...

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

details:   https://anonhg.NetBSD.org/src/rev/4f4ab474aaf1
branches:  trunk
changeset: 975656:4f4ab474aaf1
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Thu Sep 03 19:31:34 2020 +0000

description:
If we hit an unknown header type (likely to be a corrupt record), and
the user choose to not abort, skip to the next header instead of trying
to use it.
This allowed me to recover files from a corrupt dump, instead of
getting a segfault.

diffstat:

 sbin/restore/tape.c |  8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diffs (36 lines):

diff -r 66e6471d3817 -r 4f4ab474aaf1 sbin/restore/tape.c
--- a/sbin/restore/tape.c       Thu Sep 03 19:10:56 2020 +0000
+++ b/sbin/restore/tape.c       Thu Sep 03 19:31:34 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tape.c,v 1.68 2015/03/02 03:17:24 enami Exp $  */
+/*     $NetBSD: tape.c,v 1.69 2020/09/03 19:31:34 bouyer Exp $ */
 
 /*
  * Copyright (c) 1983, 1993
@@ -39,7 +39,7 @@
 #if 0
 static char sccsid[] = "@(#)tape.c     8.9 (Berkeley) 5/1/95";
 #else
-__RCSID("$NetBSD: tape.c,v 1.68 2015/03/02 03:17:24 enami Exp $");
+__RCSID("$NetBSD: tape.c,v 1.69 2020/09/03 19:31:34 bouyer Exp $");
 #endif
 #endif /* not lint */
 
@@ -1384,6 +1384,7 @@
     top:
        do {
                if (header->c_magic != FS_UFS2_MAGIC) {
+skip:
                        skipcnt++;
                        while (gethead(header) == FAIL ||
                            header->c_date != dumpdate)
@@ -1438,7 +1439,8 @@
 
                default:
                        panic("unknown tape header type %d\n", spcl.c_type);
-                       break;
+                       fprintf(stderr, "skiping to next header\n");
+                       goto skip;
 
                }
        } while (header->c_type == TS_ADDR);