From a62313c0461cf9dbc81b86a01b8ca2d8f20755ff Mon Sep 17 00:00:00 2001

From: Pavel Raiskup <praiskup@redhat.com>

Date: Thu, 16 Nov 2017 13:59:59 +0100

Subject: [PATCH] From: Sergey Poznyakoff <gray@gnu.org.ua> Date: Thu, 16 Nov

 2017 11:26:44 +0200 Subject: [PATCH] Fix the --delay-directory-restore option

* src/extract.c (find_direct_ancestor): New function.

(create_placeholder_file): Set after_links member on delayed_set_stat

entries starting from the direct ancestor of the placeholder file.

* tests/extrac21.at: New testcase.

* tests/testsuite.at: Add extrac21

* tests/Makefile.am: Likewise.

* NEWS: Update.

---

 NEWS               |  5 +++++

 src/extract.c      | 24 +++++++++++++++++-----

 tests/Makefile.am  |  1 +

 tests/extrac21.at  | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++++++

 tests/testsuite.at |  1 +

 5 files changed, 85 insertions(+), 5 deletions(-)

 create mode 100644 tests/extrac21.at

diff --git a/NEWS b/NEWS

index 36a27da..36e90ca 100644

--- a/NEWS

+++ b/NEWS

@@ -18,6 +18,11 @@ symlinks to directories when extracting from the archive.

 It is mainly intended to provide compatibility with the Slackware

 installation scripts.

+* Fixed the --delay-directory-restore option

+

+In some cases tar would restore the directory permissions too early,

+causing subsequent link extractions in that directory to fail.

+

 version 1.26 - Sergey Poznyakoff, 2011-03-12

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

index 63e4d14..0bed3e3 100644

--- a/src/extract.c

+++ b/src/extract.c

@@ -392,6 +392,24 @@ set_stat (char const *file_name,

   xattrs_selinux_set (st, file_name, typeflag);

 }

+/* Find the direct ancestor of FILE_NAME in the delayed_set_stat list.

+ */   

+static struct delayed_set_stat *

+find_direct_ancestor (char const *file_name)

+{

+  struct delayed_set_stat *h = delayed_set_stat_head;

+  while (h)

+    {

+      if (h && ! h->after_links

+	  && strncmp (file_name, h->file_name, h->file_name_len) == 0

+	  && ISSLASH (file_name[h->file_name_len])

+	  && (last_component (file_name) == file_name + h->file_name_len + 1))

+	break;

+      h = h->next;

+    }

+  return h;

+}

+

 /* For each entry H in the leading prefix of entries in HEAD that do

    not have after_links marked, mark H and fill in its dev and ino

    members.  Assume HEAD && ! HEAD->after_links.  */

@@ -1257,11 +1275,7 @@ create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)

       xheader_xattr_copy (&current_stat_info, &p->xattr_map, &p->xattr_map_size);

       strcpy (p->target, current_stat_info.link_name);

-      h = delayed_set_stat_head;

-      if (h && ! h->after_links

-	  && strncmp (file_name, h->file_name, h->file_name_len) == 0

-	  && ISSLASH (file_name[h->file_name_len])

-	  && (last_component (file_name) == file_name + h->file_name_len + 1))

+      if ((h = find_direct_ancestor (file_name)) != NULL)

 	mark_after_links (h);

       return 0;

diff --git a/tests/Makefile.am b/tests/Makefile.am

index bd8d3e8..8d0073f 100644

--- a/tests/Makefile.am

+++ b/tests/Makefile.am

@@ -80,6 +80,7 @@ TESTSUITE_AT = \

  extrac18.at\

  extrac19.at\

  extrac20.at\

+ extrac21.at\

  extrac10.at\

  extrac11.at\

  extrac12.at\

diff --git a/tests/extrac21.at b/tests/extrac21.at

new file mode 100644

index 0000000..671b101

--- /dev/null

+++ b/tests/extrac21.at

@@ -0,0 +1,59 @@

+# Test suite for GNU tar.                             -*- Autotest -*-

+# Copyright 2017 Free Software Foundation, Inc.

+#

+# This file is part of GNU tar.

+#

+# GNU tar is free software; you can redistribute it and/or modify

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

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# GNU tar is distributed in the hope that it will be useful,

+# but WITHOUT ANY WARRANTY; without even the implied warranty of

+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+# GNU General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+# When called with the --delay-directory-restore option, tar would

+# in some cases restore the directory permissions too early, before

+# attempting to replace softlink placeholders with the actual link.

+# This caused failure if the permissions forbade writing.

+#

+# The bug was caused by incorrect assumption about delayed_set_stat

+# ordering in create_placeholder_file.

+#

+# Reported by: Giuseppe Scrivano <gscrivano@gnu.org>

+# References: <878tfa17ti.fsf@redhat.com>,

+#    <http://lists.gnu.org/archive/html/bug-tar/2017-11/msg00009.html>

+

+AT_SETUP([delay-directory-restore])

+AT_KEYWORDS([extract extract21 read-only symlink delay-directory-restore])

+AT_TAR_CHECK([

+AT_UNPRIVILEGED_PREREQ

+

+mkdir a a/b a/c

+genfile --file a/b/D

+genfile --file a/c/A

+cd a/b

+ln -sf ../c/A

+cd ../..

+chmod a-w a/b

+tar --no-recurs -c -f A.tar a a/b a/b/D a/c a/b/A a/c/A

+mkdir out

+tar -C out -v -x -f A.tar --delay-directory-restore

+],

+[0],

+[a/

+a/b/

+a/b/D

+a/c/

+a/b/A

+a/c/A

+],

+[],[],[],[ustar]) # Testing one format is enough

+

+AT_CLEANUP

+

+

diff --git a/tests/testsuite.at b/tests/testsuite.at

index b540948..9b49a48 100644

--- a/tests/testsuite.at

+++ b/tests/testsuite.at

@@ -237,6 +237,7 @@ m4_include([extrac17.at])

 m4_include([extrac18.at])

 m4_include([extrac19.at])

 m4_include([extrac20.at])

+m4_include([extrac21.at])

 m4_include([label01.at])

 m4_include([label02.at])

-- 

2.14.3