From 5e1e4fae6a9eab069866eb46b2f91d60fae34efe Mon Sep 17 00:00:00 2001

From: Sergey Poznyakoff <gray@gnu.org.ua>

Date: Thu, 11 Dec 2014 12:51:21 +0200

Subject: [PATCH] Fix error recovery in copy-in mode

(+ complete sync of symlink-bad-length.at test)

* src/copyin.c (copyin_link): Fix null dereference.

(read_in_header): Fix error recovery (bug introduced by

27e0ae55).

* tests/symlink-bad-length.at: Test error recovery.

Catch various architecture-dependent error messages (suggested

by Pavel Raiskup).

---

 src/copyin.c                | 10 ++++++----

 tests/symlink-bad-length.at | 16 ++++++++++++----

 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/src/copyin.c b/src/copyin.c

index 29d0fb1..274bd49 100644

--- a/src/copyin.c

+++ b/src/copyin.c

@@ -655,7 +655,7 @@ copyin_device (struct cpio_file_stat* file_hdr)

 }

 static void

-copyin_link(struct cpio_file_stat *file_hdr, int in_file_des)

+copyin_link (struct cpio_file_stat *file_hdr, int in_file_des)

 {

   char *link_name = NULL;	/* Name of hard and symbolic links.  */

   int res;			/* Result of various function calls.  */

@@ -666,6 +666,8 @@ copyin_link(struct cpio_file_stat *file_hdr, int in_file_des)

   if (archive_format != arf_tar && archive_format != arf_ustar)

     {

       link_name = get_link_name (file_hdr, in_file_des);

+      if (!link_name)

+	return;

     }

   else

     {

@@ -1020,7 +1022,7 @@ read_in_header (struct cpio_file_stat *file_hdr, int in_des)

   file_hdr->c_tar_linkname = NULL;

-  tape_buffered_read (magic.str, in_des, 6L);

+  tape_buffered_read (magic.str, in_des, sizeof (magic.str));

   while (1)

     {

       if (append_flag)

@@ -1065,8 +1067,8 @@ read_in_header (struct cpio_file_stat *file_hdr, int in_des)

 	  break;

 	}

       bytes_skipped++;

-      memmove (magic.str, magic.str + 1, 5);

-      tape_buffered_read (magic.str, in_des, 1L);

+      memmove (magic.str, magic.str + 1, sizeof (magic.str) - 1);

+      tape_buffered_read (magic.str + sizeof (magic.str) - 1, in_des, 1L);

     }

 }

diff --git a/tests/symlink-bad-length.at b/tests/symlink-bad-length.at

index 84123a4..fd2c87e 100644

--- a/tests/symlink-bad-length.at

+++ b/tests/symlink-bad-length.at

@@ -1,5 +1,5 @@

 # Process this file with autom4te to create testsuite.  -*- Autotest -*-

-# Copyright (C) 2014 Free Software Foundation, Inc.

+# Copyright (C) 2014-2015, 2017 Free Software Foundation, Inc.

 # This program is free software; you can redistribute it and/or modify

 # it under the terms of the GNU General Public License as published by

@@ -35,18 +35,26 @@ AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=

 ])

+# The exact error message and exit status depend on the host architecture,

+# therefore strderr is filtered out and error code is not checked.

+

+# So far the only case when cpio would exit with code 0 is when it skips

+# several bytes and encounters a valid record header.  Perhaps it should

+# exit with code 2 (non-critical error), if at least one byte was skipped,

+# but that could hurt backward compatibility.

+

 AT_CHECK([

 base64 -d ARCHIVE.base64 > ARCHIVE || AT_SKIP_TEST

-TZ=UTC cpio -ntv < ARCHIVE 2>stderr

-rc=$?

+TZ=UTC cpio -ntv < ARCHIVE 2>stderr 

 cat stderr | grep -v \

     -e 'stored filename length is out of range' \

     -e 'premature end of file' \

     -e 'archive header has reverse byte-order' \

     -e 'memory exhausted' \

+    -e 'skipped [[0-9][0-9]*] bytes of junk' \

+    -e '[[0-9][0-9]*] block' \

     >&2

 echo >&2 STDERR

-test "$rc" -ne 0

 ],

 [0],

 [-rw-rw-r--   1 10029    10031          13 Nov 25  2014 FILE

-- 

2.9.3