Version 1.34

Related discussion in the Fedora pull-request:
https://src.fedoraproject.org/rpms/tar/pull-request/8

* tests/capabs_raw01.at: Newer systems (currently e.g. Fedora 34)
print getcap output in format CAP=VAL, not CAP+VAL.

NEWS

@@ -1,6 +1,22 @@
-GNU tar NEWS - User visible changes. 2021-01-07
+GNU tar NEWS - User visible changes. 2021-02-13
 Please send GNU tar bug reports to <bug-tar@gnu.org>
 
+version 1.34 - Sergey Poznyakoff, 2021-02-13
+
+* Fix extraction over pipe (savannah bug #60002)
+
+* Fix memory leak in read_header (savannah bug #59897)
+
+* Fix extraction when . and .. are unreadable
+
+See https://lists.gnu.org/archive/html/bug-tar/2021-01/msg00012.html
+
+* Gracefully handle duplicate symlinks when extracting
+
+See https://lists.gnu.org/archive/html/bug-tar/2021-01/msg00026.html
+
+* Re-initialize supplementary groups when switching to user privileges
+
 version 1.33 - Sergey Poznyakoff, 2021-01-07
 
 * POSIX extended format headers do not include PID by default

configure.ac

@@ -17,7 +17,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-AC_INIT([GNU tar], [1.33], [bug-tar@gnu.org])
+AC_INIT([GNU tar], [1.34], [bug-tar@gnu.org])
 AC_CONFIG_SRCDIR([src/tar.c])
 AC_CONFIG_AUX_DIR([build-aux])
 AC_CONFIG_HEADERS([config.h])

gnulib.modules

@@ -83,6 +83,7 @@ stat-time
 stdbool
 stdint
 stpcpy
+stdopen
 strdup-posix
 strerror
 strnlen

lib/Makefile.am

@@ -32,7 +32,6 @@ AM_CFLAGS = $(GNULIB_WARN_CFLAGS) $(WERROR_CFLAGS)
 noinst_HEADERS = \
  paxlib.h\
  rmt.h\
- stdopen.h\
  system.h\
  system-ioctl.h\
  wordsplit.h\
@@ -42,7 +41,6 @@ libtar_a_SOURCES = \
   paxerror.c paxexit-status.c paxlib.h paxnames.c \
   rtapelib.c \
   rmt.h \
-  stdopen.c stdopen.h \
   system.h system-ioctl.h \
   wordsplit.c\
   xattr-at.c

lib/stdopen.c

@@ -1,76 +0,0 @@
-/* stdopen.c - ensure that the three standard file descriptors are in use
-
-   Copyright 2005-2021 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
-   the Free Software Foundation; either version 3, or (at your option)
-   any later version.
-
-   This program 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/>.  */
-
-/* Written by Paul Eggert and Jim Meyering.  */
-
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-#include "stdopen.h"
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
-
-/* Try to ensure that all of the standard file numbers (0, 1, 2)
-   are in use.  Without this, each application would have to guard
-   every call to open, dup, fopen, etc. with tests to ensure they
-   don't use one of the special file numbers when opening a file.
-   Return false if at least one of the file descriptors is initially
-   closed and an attempt to reopen it fails.  Otherwise, return true.  */
-bool
-stdopen (void)
-{
-  int fd;
-  bool ok = true;
-
-  for (fd = 0; fd <= 2; fd++)
-    {
-      if (fcntl (fd, F_GETFD) < 0)
-        {
-          if (errno != EBADF)
-            ok = false;
-          else
-            {
-              static const int contrary_mode[]
-                = { O_WRONLY, O_RDONLY, O_RDONLY };
-              int mode = contrary_mode[fd];
-              int new_fd;
-              /* Open /dev/null with the contrary mode so that the typical
-                 read (stdin) or write (stdout, stderr) operation will fail.
-                 With descriptor 0, we can do even better on systems that
-                 have /dev/full, by opening that write-only instead of
-                 /dev/null.  The only drawback is that a write-provoked
-                 failure comes with a misleading errno value, ENOSPC.  */
-              if (mode == O_RDONLY
-                  || (new_fd = open ("/dev/full", mode) != fd))
-                new_fd = open ("/dev/null", mode);
-              if (new_fd != fd)
-                {
-                  if (0 <= new_fd)
-                    close (new_fd);
-                  ok = false;
-                }
-            }
-        }
-    }
-
-  return ok;
-}

lib/stdopen.h

@@ -1,16 +0,0 @@
-#ifndef STDOPEN_H
-# define STDOPEN_H 1
-
-# include <stdbool.h>
-
-# ifdef __cplusplus
-extern "C" {
-# endif
-
-bool stdopen (void);
-
-# ifdef __cplusplus
-}
-# endif
-
-#endif

po/.gitignore

@@ -1,3 +1,4 @@
+/Makefile.in.in
 /Makevars.template~
 /Makefile.in.in~
 *.gmo

src/delete.c

@@ -147,6 +147,23 @@ write_recent_bytes (char *data, size_t bytes)
     write_record (1);
 }
 
+static inline void
+flush_file (void)
+{
+  off_t blocks_to_skip;
+
+  set_next_block_after (current_header);
+  blocks_to_skip = (current_stat_info.stat.st_size
+			  + BLOCKSIZE - 1) / BLOCKSIZE;
+
+  while (record_end - current_block <= blocks_to_skip)
+    {
+      blocks_to_skip -= (record_end - current_block);
+      flush_archive ();
+    }
+  current_block += blocks_to_skip;
+}
+
 void
 delete_archive_members (void)
 {
@@ -155,7 +172,6 @@ delete_archive_members (void)
 
   /* FIXME: Should clean the routine before cleaning these variables :-( */
   struct name *name;
-  off_t blocks_to_skip = 0;
   off_t blocks_to_keep = 0;
   int kept_blocks_in_record;
 
@@ -163,6 +179,7 @@ delete_archive_members (void)
   open_archive (ACCESS_UPDATE);
   acting_as_filter = strcmp (archive_name_array[0], "-") == 0;
 
+  /* Skip to the first member that matches the name list. */
   do
     {
       enum read_header status = read_header (&current_header,
@@ -243,15 +260,12 @@ delete_archive_members (void)
 
       if (logical_status == HEADER_SUCCESS)
 	{
-	  /* FIXME: Pheew!  This is crufty code!  */
 	  logical_status = HEADER_STILL_UNREAD;
-	  goto flush_file;
+	  flush_file ();
 	}
 
-      /* FIXME: Solaris 2.4 Sun cc (the ANSI one, not the old K&R) says:
+      /* Skip matching members and move the rest up the archive. */
-	 "delete.c", line 223: warning: loop not entered at top
+      while (logical_status != HEADER_END_OF_FILE)
-	 Reported by Bruno Haible.  */
-      while (1)
 	{
 	  enum read_header status;
 
@@ -259,49 +273,27 @@ delete_archive_members (void)
 
 	  if (current_block == record_end)
 	    flush_archive ();
+
 	  status = read_header (&current_header, &current_stat_info,
 				read_header_auto);
 
-	  xheader_decode (&current_stat_info);
+	  switch (status)
-
-	  if (status == HEADER_ZERO_BLOCK && ignore_zeros_option)
 	    {
-	      set_next_block_after (current_header);
+	    case HEADER_STILL_UNREAD:
-	      continue;
+	    case HEADER_SUCCESS_EXTENDED:
-	    }
+	      abort ();
-	  if (status == HEADER_END_OF_FILE || status == HEADER_ZERO_BLOCK)
-	    {
-	      logical_status = HEADER_END_OF_FILE;
-	      break;
-	    }
-
-	  if (status == HEADER_FAILURE)
-	    {
-	      ERROR ((0, 0, _("Deleting non-header from archive")));
-	      set_next_block_after (current_header);
-	      continue;
-	    }
 
+	    case HEADER_SUCCESS:
 	      /* Found another header.  */
+	      xheader_decode (&current_stat_info);
 
 	      if ((name = name_scan (current_stat_info.file_name)) != NULL)
 		{
 		  name->found_count++;
 		  if (ISFOUND (name))
 		    {
-		flush_file:
+		      flush_file ();
-		  set_next_block_after (current_header);
+		      break;
-		  blocks_to_skip = (current_stat_info.stat.st_size
-				    + BLOCKSIZE - 1) / BLOCKSIZE;
-
-		  while (record_end - current_block <= blocks_to_skip)
-		    {
-		      blocks_to_skip -= (record_end - current_block);
-		      flush_archive ();
-		    }
-		  current_block += blocks_to_skip;
-		  blocks_to_skip = 0;
-		  continue;
 		    }
 		}
 	      /* Copy header.  */
@@ -313,8 +305,10 @@ delete_archive_members (void)
 		}
 	      else
 		{
-	      write_recent_blocks (recent_long_name, recent_long_name_blocks);
+		  write_recent_blocks (recent_long_name,
-	      write_recent_blocks (recent_long_link, recent_long_link_blocks);
+				       recent_long_name_blocks);
+		  write_recent_blocks (recent_long_link,
+				       recent_long_link_blocks);
 		}
 	      new_record[new_blocks] = *current_header;
 	      new_blocks++;
@@ -349,7 +343,8 @@ delete_archive_members (void)
 		  if (! count)
 		    abort ();
 
-	      memcpy (new_record + new_blocks, current_block, count * BLOCKSIZE);
+		  memcpy (new_record + new_blocks, current_block,
+			  count * BLOCKSIZE);
 		  new_blocks += count;
 		  current_block += count;
 		  blocks_to_keep -= count;
@@ -358,6 +353,28 @@ delete_archive_members (void)
 		  if (new_blocks == blocking_factor)
 		    write_record (1);
 		}
+	      break;
+
+	    case HEADER_ZERO_BLOCK:
+	      if (ignore_zeros_option)
+		set_next_block_after (current_header);
+	      else
+		logical_status = HEADER_END_OF_FILE;
+	      break;
+
+	    case HEADER_END_OF_FILE:
+	      logical_status = HEADER_END_OF_FILE;
+	      break;
+
+	    case HEADER_FAILURE:
+	      ERROR ((0, 0, _("Deleting non-header from archive")));
+	      set_next_block_after (current_header);
+	      break;
+
+	    default:
+	      abort ();
+	    }
+	  tar_stat_destroy (&current_stat_info);
 	}
 
       if (logical_status == HEADER_END_OF_FILE)

src/extract.c

@@ -1323,6 +1323,41 @@ extract_file (char *file_name, int typeflag)
   return status;
 }
 
+/* Find a delayed_link structure corresponding to the source NAME.
+   Such a structure exists in the delayed link list only if the link
+   placeholder file has been created. Therefore, try to stat the NAME
+   first. If it doesn't exist, there is no matching entry in the list.
+   Otherwise, look for the entry in list which has the matching dev
+   and ino numbers.
+   
+   This approach avoids scanning the singly-linked list in obvious cases
+   and does not rely on comparing file names, which may differ for
+   various reasons (e.g. relative vs. absolute file names).
+ */
+static struct delayed_link *
+find_delayed_link_source (char const *name)
+{
+  struct delayed_link *dl;
+  struct stat st;
+
+  if (!delayed_link_head)
+    return NULL;
+  
+  if (fstatat (chdir_fd, name, &st, AT_SYMLINK_NOFOLLOW))
+    {
+      if (errno != ENOENT)
+	stat_error (name);
+      return NULL;
+    }
+  
+  for (dl = delayed_link_head; dl; dl = dl->next)
+    {
+      if (dl->dev == st.st_dev && dl->ino == st.st_ino)
+	break;
+    }
+  return dl;
+}
+  
 /* Create a placeholder file with name FILE_NAME, which will be
    replaced after other extraction is done by a symbolic link if
    IS_SYMLINK is true, and by a hard link otherwise.  Set
@@ -1342,6 +1377,15 @@ create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made,
 
   while ((fd = openat (chdir_fd, file_name, O_WRONLY | O_CREAT | O_EXCL, 0)) < 0)
     {
+      if (errno == EEXIST && find_delayed_link_source (file_name))
+	{
+	  /* The placeholder file has already been created.  This means
+	     that the link being extracted is a duplicate of an already
+	     processed one.  Skip it.
+	   */
+	  return 0;
+	}
+      
       switch (maybe_recoverable (file_name, false, interdir_made))
 	{
 	case RECOVER_OK:
@@ -1416,41 +1460,6 @@ create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made,
   return -1;
 }
 
-/* Find a delayed_link structure corresponding to the source NAME.
-   Such a structure exists in the delayed link list only if the link
-   placeholder file has been created. Therefore, try to stat the NAME
-   first. If it doesn't exist, there is no matching entry in the list.
-   Otherwise, look for the entry in list which has the matching dev
-   and ino numbers.
-   
-   This approach avoids scanning the singly-linked list in obvious cases
-   and does not rely on comparing file names, which may differ for
-   various reasons (e.g. relative vs. absolute file names).
- */
-static struct delayed_link *
-find_delayed_link_source (char const *name)
-{
-  struct delayed_link *dl;
-  struct stat st;
-
-  if (!delayed_link_head)
-    return NULL;
-  
-  if (fstatat (chdir_fd, name, &st, AT_SYMLINK_NOFOLLOW))
-    {
-      if (errno != ENOENT)
-	stat_error (name);
-      return NULL;
-    }
-  
-  for (dl = delayed_link_head; dl; dl = dl->next)
-    {
-      if (dl->dev == st.st_dev && dl->ino == st.st_ino)
-	break;
-    }
-  return dl;
-}
-  
 static int
 extract_link (char *file_name, int typeflag)
 {
@@ -1708,7 +1717,12 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
       extractor = extract_file;
     }
 
-  if (!EXTRACT_OVER_PIPE)
+  if (EXTRACT_OVER_PIPE)
+    {
+      if (extractor != extract_file)
+	return false;
+    }
+  else
     {
       switch (old_files_option)
 	{

src/list.c

@@ -408,26 +408,27 @@ read_header (union block **return_block, struct tar_stat_info *info,
 	     enum read_header_mode mode)
 {
   union block *header;
-  union block *header_copy;
   char *bp;
   union block *data_block;
   size_t size, written;
-  union block *next_long_name = 0;
+  union block *next_long_name = NULL;
-  union block *next_long_link = 0;
+  union block *next_long_link = NULL;
   size_t next_long_name_blocks = 0;
   size_t next_long_link_blocks = 0;
+  enum read_header status = HEADER_SUCCESS;
   
   while (1)
     {
-      enum read_header status;
-
       header = find_next_block ();
       *return_block = header;
       if (!header)
-	return HEADER_END_OF_FILE;
+	{
+	  status = HEADER_END_OF_FILE;
+	  break;
+	}
 
       if ((status = tar_checksum (header, false)) != HEADER_SUCCESS)
-	return status;
+	break;
 
       /* Good block.  Decode file size and return.  */
 
@@ -437,7 +438,10 @@ read_header (union block **return_block, struct tar_stat_info *info,
 	{
 	  info->stat.st_size = OFF_FROM_HEADER (header->header.size);
 	  if (info->stat.st_size < 0)
-	    return HEADER_FAILURE;
+	    {
+	      status = HEADER_FAILURE;
+	      break;
+	    }
 	}
 
       if (header->header.typeflag == GNUTYPE_LONGNAME
@@ -447,10 +451,14 @@ read_header (union block **return_block, struct tar_stat_info *info,
 	  || header->header.typeflag == SOLARIS_XHDTYPE)
 	{
 	  if (mode == read_header_x_raw)
-	    return HEADER_SUCCESS_EXTENDED;
+	    {
+	      status = HEADER_SUCCESS_EXTENDED;
+	      break;
+	    }
 	  else if (header->header.typeflag == GNUTYPE_LONGNAME
 		   || header->header.typeflag == GNUTYPE_LONGLINK)
 	    {
+	      union block *header_copy;
 	      size_t name_size = info->stat.st_size;
 	      size_t n = name_size % BLOCKSIZE;
 	      size = name_size + BLOCKSIZE;
@@ -517,7 +525,10 @@ read_header (union block **return_block, struct tar_stat_info *info,
 	      xheader_decode_global (&xhdr);
 	      xheader_destroy (&xhdr);
 	      if (mode == read_header_x_global)
-		return HEADER_SUCCESS_EXTENDED;
+		{
+		  status = HEADER_SUCCESS_EXTENDED;
+		  break;
+		}
 	    }
 
 	  /* Loop!  */
@@ -536,6 +547,7 @@ read_header (union block **return_block, struct tar_stat_info *info,
 	      name = next_long_name->buffer + BLOCKSIZE;
 	      recent_long_name = next_long_name;
 	      recent_long_name_blocks = next_long_name_blocks;
+	      next_long_name = NULL;
 	    }
 	  else
 	    {
@@ -567,6 +579,7 @@ read_header (union block **return_block, struct tar_stat_info *info,
 	      name = next_long_link->buffer + BLOCKSIZE;
 	      recent_long_link = next_long_link;
 	      recent_long_link_blocks = next_long_link_blocks;
+	      next_long_link = NULL;
 	    }
 	  else
 	    {
@@ -578,9 +591,12 @@ read_header (union block **return_block, struct tar_stat_info *info,
 	    }
 	  assign_string (&info->link_name, name);
 
-	  return HEADER_SUCCESS;
+	  break;
 	}
     }
+  free (next_long_name);
+  free (next_long_link);
+  return status;
 }
 
 #define ISOCTAL(c) ((c)>='0'&&(c)<='7')

src/misc.c

@@ -908,8 +908,6 @@ chdir_count (void)
 int
 chdir_arg (char const *dir)
 {
-  char *absdir;
-
   if (wd_count == wd_alloc)
     {
       if (wd_alloc == 0)
@@ -919,9 +917,7 @@ chdir_arg (char const *dir)
       if (! wd_count)
 	{
 	  wd[wd_count].name = ".";
-	  wd[wd_count].abspath = xgetcwd ();
+	  wd[wd_count].abspath = NULL;
-	  if (!wd[wd_count].abspath)
-	    call_arg_fatal ("getcwd", ".");
 	  wd[wd_count].fd = AT_FDCWD;
 	  wd_count++;
 	}
@@ -938,22 +934,8 @@ chdir_arg (char const *dir)
 	return wd_count - 1;
     }
 
-
-  /* If the given name is absolute, use it to represent this directory;
-     otherwise, construct a name based on the previous -C option.  */
-  if (IS_ABSOLUTE_FILE_NAME (dir))
-    absdir = xstrdup (dir);
-  else if (wd[wd_count - 1].abspath)
-    {
-      namebuf_t nbuf = namebuf_create (wd[wd_count - 1].abspath);
-      namebuf_add_dir (nbuf, dir);
-      absdir = namebuf_finish (nbuf);
-    }
-  else
-    absdir = 0;
-
   wd[wd_count].name = dir;
-  wd[wd_count].abspath = absdir;
+  wd[wd_count].abspath = NULL;
   wd[wd_count].fd = 0;
   return wd_count++;
 }
@@ -1054,6 +1036,40 @@ tar_getcdpath (int idx)
 	}
       return cwd;
     }
+
+  if (!wd[idx].abspath)
+    {
+      int i;
+      int save_cwdi = chdir_current;
+      
+      for (i = idx; i >= 0; i--)
+	if (wd[i].abspath)
+	  break;
+      
+      while (++i <= idx)
+	{
+	  chdir_do (i);
+	  if (i == 0)
+	    {
+	      if ((wd[i].abspath = xgetcwd ()) == NULL)
+		call_arg_fatal ("getcwd", ".");
+	    }
+	  else if (IS_ABSOLUTE_FILE_NAME (wd[i].name))
+	    /* If the given name is absolute, use it to represent this
+	       directory; otherwise, construct a name based on the
+	       previous -C option.  */
+	    wd[i].abspath = xstrdup (wd[i].name);
+	  else
+	    {
+	      namebuf_t nbuf = namebuf_create (wd[i - 1].abspath);
+	      namebuf_add_dir (nbuf, wd[i].name);
+	      wd[i].abspath = namebuf_finish (nbuf);
+	    }
+	}
+
+      chdir_do (save_cwdi);
+    }
+	   
   return wd[idx].abspath;
 }
 

src/tar.c

@@ -2248,7 +2248,7 @@ parse_default_options (struct tar_args *args)
       if (argp_parse (&argp,
 		      ws.ws_offs + ws.ws_wordc,
 		      ws.ws_wordv,
-		      ARGP_IN_ORDER|ARGP_NO_EXIT, &idx, &args))
+		      ARGP_IN_ORDER|ARGP_NO_EXIT, &idx, args))
 	abort (); /* shouldn't happen */
       args->loc = save_loc_ptr;
       if (name_more_files ())
@@ -2751,8 +2751,11 @@ main (int argc, char **argv)
 
   set_quoting_style (0, DEFAULT_QUOTING_STYLE);
 
+  close_stdout_set_file_name (_("stdout"));
   /* Make sure we have first three descriptors available */
-  stdopen ();
+  if (stdopen ())
+    FATAL_ERROR ((0, 0, "%s",
+		  _("failed to assert availability of the standard file descriptors")));
 
   /* Pre-allocate a few structures.  */
 

tests/Makefile.am

@@ -122,6 +122,7 @@ TESTSUITE_AT = \
  extrac21.at\
  extrac22.at\
  extrac23.at\
+ extrac24.at\
  filerem01.at\
  filerem02.at\
  dirrem01.at\

tests/capabs_raw01.at

@@ -44,10 +44,11 @@ rm -rf dir
 # restore _all_ xattrs (not just the user.* domain)
 tar --xattrs --xattrs-include='*' -xf archive.tar
 
-getcap dir/file
+# Newer systems print = instead of + here
+getcap dir/file | sed 's/+/=/'
 ],
 [0],
-[dir/file = cap_chown+ei
+[dir/file = cap_chown=ei
 ])
 
 AT_CLEANUP

tests/extrac24.at

@@ -0,0 +1,41 @@
+# Test suite for GNU tar.                             -*- autotest -*-
+# Copyright 2021 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/>.
+AT_SETUP([--to-stdout])
+AT_KEYWORDS([extract extrac24 to-stdout])
+
+# Description: When extracting over pipe, only regular files should be
+# extracted.  In tar 1.33 this was broken, so that members of other types
+# (in particular, directories) were extracted as usual.  This test ensures
+# that this is no longer the case.
+#
+# References: https://bugs.archlinux.org/task/69373,
+#             https://savannah.gnu.org/bugs/?60002
+
+AT_TAR_CHECK([
+mkdir dir/
+echo TEXT > dir/file
+tar cf a.tar dir
+rm -r dir
+tar --extract --to-stdout --file a.tar
+test -d dir
+],
+[1],
+[TEXT
+])
+
+AT_CLEANUP

tests/testsuite.at

@@ -344,6 +344,7 @@ m4_include([extrac20.at])
 m4_include([extrac21.at])
 m4_include([extrac22.at])
 m4_include([extrac23.at])
+m4_include([extrac24.at])
 
 m4_include([backup01.at])