tar: --dereference consistency

This closes another race condition, that occurs when overwriting a
symlink with a regular file.
* NEWS (--dereference consistency): New section.
* doc/tar.texi (Option Summary): Describe new --deference behavior.
(dereference): Likewise.  Remove discussion that I didn't follow,
even before --dereference was changed.
* src/common.h (deref_stat, set_file_atime): Adjust signatures.
* src/compare.c (diff_file, diff_multivol): Respect open_read_flags
instead of rolling our own flags.  This implements the new behavior
for --dereference.
(diff_file, diff_dumpdir): Likewise, for fstatat_flags.
* src/create.c: Adjust to set_file_atime signature change.
* src/extract.c (mark_after_links, file_newer_p, extract_dir):
Likewise.
* src/incremen.c (try_purge_directory): Likewise.
* src/misc.c (maybe_backup_file): Likewise.
* src/extract.c (file_newer_p): New arg STP.  All callers changed.
(maybe_recoverable): New arg REGULAR.  All callers changed.
Handle the case of overwriting a symlink with a regular file,
when --overwrite is specified but --dereference is not.
(open_output_file): Add O_CLOEXEC, O_NOCTTY, O_NONBLOCK for
consistency with file creation.  Add O_NOFOLLOW if
overwriting_old_files && ! dereference_option.
* src/incremen.c (update_parent_directory): Use fstat, not fstatat;
there's less to go wrong.
* src/misc.c (deref_stat): Remove DEREF arg.  All callers changed.
Instead, use fstatat_flags.
(set_file_atime): Remove ATFLAG arg.  All callers changed.
Instead, use fstatat_flags.
* src/names.c, src/update.c: Adjust to deref_stat signature change.
* src/tar.c (get_date_or_file): Use stat, not deref_stat, as this
is not a file to be archived.
* tests/Makefile.am (TESTSUITE_AT): Add extrac13.at.
* tests/extrac13.at: New file.
* tests/testsuite.at: Include it.

diff --git a/NEWS b/NEWS
index 58fd2ff3e048787ed81dcd44c9119adaf9471267..1484c555a8fafecab89d8a63bc3ffbbf0e5ceef5 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,4 @@
-GNU tar NEWS - User visible changes. 2010-09-17
+GNU tar NEWS - User visible changes. 2010-09-23

 Please send GNU tar bug reports to <bug-tar@gnu.org>
 
 \f
 Please send GNU tar bug reports to <bug-tar@gnu.org>
 
 \f


@@ -33,6 +33,22 @@ supports this.  For example, recent versions of the Linux kernel
 support setting times on symlinks, and some BSD kernels also support
 symlink permissions.
 
 support setting times on symlinks, and some BSD kernels also support
 symlink permissions.
 

+** --dereference consistency
+
+The --dereference (-h) option now applies to files that are copied
+into or out of archives, independently of other options.  For example,
+if F is a symbolic link and archive.tar contains a regular-file member
+also named F, "tar --overwrite -x -f archive.tar F" now overwrites F
+itself, rather than the file that F points to.  (To overwrite the file
+that F points to, add the --dereference (-h) option.)  Formerly,
+--dereference was intended to apply only when using the -c option, but
+the implementation was not consistent.
+
+Also, the --dereference option no longer affects accesses to other
+files, such as archives and time stamp files.  Symbolic links to these
+files are always followed.  Previously, the links were usually but not
+always followed.
+

 ** Spurious error diagnostics on broken pipe.
 
 When receiving SIGPIPE, tar would exit with error status and
 ** Spurious error diagnostics on broken pipe.
 
 When receiving SIGPIPE, tar would exit with error status and

diff --git a/doc/tar.texi b/doc/tar.texi
index 983e47a3994ef79724ddda7038a86388b2a8d278..23a5e76cef9f209efaa213d36770b93e7128010a 100644 (file)
--- a/doc/tar.texi
+++ b/doc/tar.texi
@@ -2559,9 +2559,9 @@ directories until the end of extraction. @xref{Directory Modification Times and
 @item --dereference
 @itemx -h
 
 @item --dereference
 @itemx -h
 

-When creating a @command{tar} archive, @command{tar} will archive the
-file that a symbolic link points to, rather than archiving the
-symlink.  @xref{dereference}.
+When reading or writing a file to be archived, @command{tar} accesses
+the file that a symbolic link points to, rather than the symlink
+itself.  @xref{dereference}.

 
 @opsummary{directory}
 @item --directory=@var{dir}
 
 @opsummary{directory}
 @item --directory=@var{dir}


@@ -9319,30 +9319,25 @@ than System V's.
 Normally, when @command{tar} archives a symbolic link, it writes a
 block to the archive naming the target of the link.  In that way, the
 @command{tar} archive is a faithful record of the file system contents.
 Normally, when @command{tar} archives a symbolic link, it writes a
 block to the archive naming the target of the link.  In that way, the
 @command{tar} archive is a faithful record of the file system contents.

-@option{--dereference} (@option{-h}) is used with @option{--create} (@option{-c}), and causes
-@command{tar} to archive the files symbolic links point to, instead of
-the links themselves.  When this option is used, when @command{tar}
-encounters a symbolic link, it will archive the linked-to file,
-instead of simply recording the presence of a symbolic link.
-
-The name under which the file is stored in the file system is not
-recorded in the archive.  To record both the symbolic link name and
-the file name in the system, archive the file under both names.  If
-all links were recorded automatically by @command{tar}, an extracted file
-might be linked to a file name that no longer exists in the file
-system.
-
-If a linked-to file is encountered again by @command{tar} while creating
-the same archive, an entire second copy of it will be stored.  (This
-@emph{might} be considered a bug.)
+When @option{--dereference} (@option{-h}) is used with
+@option{--create} (@option{-c}), @command{tar} archives the files
+symbolic links point to, instead of
+the links themselves.

 
 

-So, for portable archives, do not archive symbolic links as such,
-and use @option{--dereference} (@option{-h}): many systems do not support
+When creating portable archives, use @option{--dereference}
+(@option{-h}): some systems do not support

 symbolic links, and moreover, your distribution might be unusable if
 it contains unresolved symbolic links.
 
 symbolic links, and moreover, your distribution might be unusable if
 it contains unresolved symbolic links.
 

-The @option{--dereference} option is not secure if an untrusted user
-can modify files during creation or extraction.  @xref{Security}.
+When reading from an archive, the @option{--dereference} (@option{-h})
+option causes @command{tar} to follow an already-existing symbolic
+link when @command{tar} writes or reads a file named in the archive.
+Ordinarily, @command{tar} does not follow such a link, though it may
+remove the link before writing a new file.  @xref{Dealing with Old
+Files}.
+
+The @option{--dereference} option is unsafe if an untrusted user can
+modify directories while @command{tar} is running.  @xref{Security}.

 
 @node hard links
 @subsection Hard Links
 
 @node hard links
 @subsection Hard Links

diff --git a/src/common.h b/src/common.h
index 12a488919d754a1945a9c4693e096105abe57901..192cf9e5b64a77c0a7857b0a85f4b3f222187b9d 100644 (file)
--- a/src/common.h
+++ b/src/common.h
@@ -611,7 +611,7 @@ int remove_any_file (const char *file_name, enum remove_option option);
 bool maybe_backup_file (const char *file_name, bool this_is_the_archive);
 void undo_last_backup (void);
 
 bool maybe_backup_file (const char *file_name, bool this_is_the_archive);
 void undo_last_backup (void);
 

-int deref_stat (bool deref, char const *name, struct stat *buf);
+int deref_stat (char const *name, struct stat *buf);

 
 extern int chdir_current;
 extern int chdir_fd;
 
 extern int chdir_current;
 extern int chdir_fd;


@@ -640,7 +640,7 @@ void xpipe (int fd[2]);
 
 void *page_aligned_alloc (void **ptr, size_t size);
 int set_file_atime (int fd, int parentfd, char const *file,
 
 void *page_aligned_alloc (void **ptr, size_t size);
 int set_file_atime (int fd, int parentfd, char const *file,

-                   struct timespec atime, int atflag);
+                   struct timespec atime);

 
 /* Module names.c.  */
 
 
 /* Module names.c.  */
 

diff --git a/src/compare.c b/src/compare.c
index 1ee9bcb19d9f7e3d33ccc783f5b64cfba0cd6955..6b7e6d8747053bebfef98bcf27707ba9d3b1d489 100644 (file)
--- a/src/compare.c
+++ b/src/compare.c
@@ -151,7 +151,7 @@ read_and_process (struct tar_stat_info *st, int (*processor) (size_t, char *))
 static int
 get_stat_data (char const *file_name, struct stat *stat_data)
 {
 static int
 get_stat_data (char const *file_name, struct stat *stat_data)
 {

-  int status = deref_stat (dereference_option, file_name, stat_data);
+  int status = deref_stat (file_name, stat_data);

 
   if (status != 0)
     {
 
   if (status != 0)
     {


@@ -217,14 +217,7 @@ diff_file (void)
        }
       else
        {
        }
       else
        {

-         int atime_flag =
-           (atime_preserve_option == system_atime_preserve
-            ? O_NOATIME
-            : 0);
-
-         diff_handle = openat (chdir_fd, file_name,
-                               (O_RDONLY | O_BINARY | O_CLOEXEC | O_NOCTTY
-                                | O_NONBLOCK | atime_flag));
+         diff_handle = openat (chdir_fd, file_name, open_read_flags);

 
          if (diff_handle < 0)
            {
 
          if (diff_handle < 0)
            {


@@ -244,8 +237,7 @@ diff_file (void)
              if (atime_preserve_option == replace_atime_preserve)
                {
                  struct timespec atime = get_stat_atime (&stat_data);
              if (atime_preserve_option == replace_atime_preserve)
                {
                  struct timespec atime = get_stat_atime (&stat_data);

-                 if (set_file_atime (diff_handle, chdir_fd, file_name,
-                                     atime, 0)
+                 if (set_file_atime (diff_handle, chdir_fd, file_name, atime)

                      != 0)
                    utime_error (file_name);
                }
                      != 0)
                    utime_error (file_name);
                }


@@ -372,7 +364,7 @@ diff_dumpdir (void)
   dev_t dev = 0;
   struct stat stat_data;
 
   dev_t dev = 0;
   struct stat stat_data;
 

-  if (deref_stat (true, current_stat_info.file_name, &stat_data))
+  if (deref_stat (current_stat_info.file_name, &stat_data) != 0)

     {
       if (errno == ENOENT)
        stat_warn (current_stat_info.file_name);
     {
       if (errno == ENOENT)
        stat_warn (current_stat_info.file_name);


@@ -399,10 +391,6 @@ diff_multivol (void)
   struct stat stat_data;
   int fd, status;
   off_t offset;
   struct stat stat_data;
   int fd, status;
   off_t offset;

-  int atime_flag =
-    (atime_preserve_option == system_atime_preserve
-     ? O_NOATIME
-     : 0);

 
   if (current_stat_info.had_trailing_slash)
     {
 
   if (current_stat_info.had_trailing_slash)
     {


@@ -429,9 +417,7 @@ diff_multivol (void)
     }
 
 
     }
 
 

-  fd = openat (chdir_fd, current_stat_info.file_name,
-              (O_RDONLY | O_BINARY | O_CLOEXEC | O_NOCTTY | O_NONBLOCK
-               | atime_flag));
+  fd = openat (chdir_fd, current_stat_info.file_name, open_read_flags);

 
   if (fd < 0)
     {
 
   if (fd < 0)
     {

diff --git a/src/create.c b/src/create.c
index 26993c21e5792be036be572e930a4887556b9b2b..05af0d9062cee9e6d6102df1baa9e4a35b7cb601 100644 (file)
--- a/src/create.c
+++ b/src/create.c
@@ -1795,9 +1795,7 @@ dump_file0 (struct tar_stat_info *st, char const *name, char const *p)
              set_exit_status (TAREXIT_DIFFERS);
            }
          else if (atime_preserve_option == replace_atime_preserve
              set_exit_status (TAREXIT_DIFFERS);
            }
          else if (atime_preserve_option == replace_atime_preserve

-                  && (set_file_atime (fd, parentfd, name,
-                                      st->atime, fstatat_flags)
-                      != 0))
+                  && set_file_atime (fd, parentfd, name, st->atime) != 0)

            utime_error (p);
        }
 
            utime_error (p);
        }
 

diff --git a/src/extract.c b/src/extract.c
index 2730a03ab7129c824e42e316a66652ce6affb056..0a1a032989d3d59a1aeb989f3bd6a3fe08ea1422 100644 (file)
--- a/src/extract.c
+++ b/src/extract.c
@@ -375,7 +375,7 @@ mark_after_links (struct delayed_set_stat *head)
       struct stat st;
       h->after_links = 1;
 
       struct stat st;
       h->after_links = 1;
 

-      if (fstatat (chdir_fd, h->file_name, &st, 0) != 0)
+      if (deref_stat (h->file_name, &st) != 0)

        stat_error (h->file_name);
       else
        {
        stat_error (h->file_name);
       else
        {


@@ -548,27 +548,32 @@ make_directories (char *file_name)
   return did_something;                /* tell them to retry if we made one */
 }
 
   return did_something;                /* tell them to retry if we made one */
 }
 

+/* Return true if FILE_NAME (with status *STP, if STP) is not a
+   directory, and has a time stamp newer than (or equal to) that of
+   TAR_STAT.  */

 static bool
 static bool

-file_newer_p (const char *file_name, struct tar_stat_info *tar_stat)
+file_newer_p (const char *file_name, struct stat const *stp,
+             struct tar_stat_info *tar_stat)

 {
   struct stat st;
 
 {
   struct stat st;
 

-  if (fstatat (chdir_fd, file_name, &st, 0))
+  if (!stp)

     {
     {

-      if (errno != ENOENT)
+      if (deref_stat (file_name, &st) != 0)

        {
        {

-         stat_warn (file_name);
-         /* Be on the safe side: if the file does exist assume it is newer */
-         return true;
+         if (errno != ENOENT)
+           {
+             stat_warn (file_name);
+             /* Be safer: if the file exists, assume it is newer.  */
+             return true;
+           }
+         return false;

        }
        }

-      return false;
-    }
-  if (!S_ISDIR (st.st_mode)
-      && tar_timespec_cmp (tar_stat->mtime, get_stat_mtime (&st)) <= 0)
-    {
-      return true;
+      stp = &st;

     }
     }

-  return false;
+
+  return (! S_ISDIR (stp->st_mode)
+         && tar_timespec_cmp (tar_stat->mtime, get_stat_mtime (stp)) <= 0);

 }
 
 #define RECOVER_NO 0
 }
 
 #define RECOVER_NO 0


@@ -580,18 +585,39 @@ file_newer_p (const char *file_name, struct tar_stat_info *tar_stat)
    Return RECOVER_OK if we somewhat increased our chances at a successful
    extraction, RECOVER_NO if there are no chances, and RECOVER_SKIP if the
    caller should skip extraction of that member.  The value of errno is
    Return RECOVER_OK if we somewhat increased our chances at a successful
    extraction, RECOVER_NO if there are no chances, and RECOVER_SKIP if the
    caller should skip extraction of that member.  The value of errno is

-   properly restored on returning RECOVER_NO.  */
+   properly restored on returning RECOVER_NO.
+
+   If REGULAR, the caller was trying to extract onto a regular file.
+
+   Set *INTERDIR_MADE if an intermediate directory is made as part of
+   the recovery process.  */

 
 static int
 
 static int

-maybe_recoverable (char *file_name, bool *interdir_made)
+maybe_recoverable (char *file_name, bool regular, bool *interdir_made)

 {
   int e = errno;
 {
   int e = errno;

+  struct stat st;
+  struct stat const *stp = 0;

 
   if (*interdir_made)
     return RECOVER_NO;
 
 
   if (*interdir_made)
     return RECOVER_NO;
 

-  switch (errno)
+  switch (e)

     {
     {

+    case ELOOP:
+      if (! regular
+         || old_files_option != OVERWRITE_OLD_FILES || dereference_option)
+       break;
+      if (strchr (file_name, '/'))
+       {
+         if (deref_stat (file_name, &st) != 0)
+           break;
+         stp = &st;
+       }
+
+      /* The caller tried to open a symbolic link with O_NOFOLLOW.
+        Fall through, treating it as an already-existing file.  */
+

     case EEXIST:
       /* Remove an old file, if the options allow this.  */
 
     case EEXIST:
       /* Remove an old file, if the options allow this.  */
 


@@ -601,21 +627,16 @@ maybe_recoverable (char *file_name, bool *interdir_made)
          return RECOVER_SKIP;
 
        case KEEP_NEWER_FILES:
          return RECOVER_SKIP;
 
        case KEEP_NEWER_FILES:

-         if (file_newer_p (file_name, &current_stat_info))
-           {
-             errno = e;
-             return RECOVER_NO;
-           }
+         if (file_newer_p (file_name, stp, &current_stat_info))
+           break;

          /* FALL THROUGH */
 
        case DEFAULT_OLD_FILES:
        case NO_OVERWRITE_DIR_OLD_FILES:
        case OVERWRITE_OLD_FILES:
          /* FALL THROUGH */
 
        case DEFAULT_OLD_FILES:
        case NO_OVERWRITE_DIR_OLD_FILES:
        case OVERWRITE_OLD_FILES:

-         {
-           int r = remove_any_file (file_name, ORDINARY_REMOVE_OPTION);
-           errno = EEXIST;
-           return r > 0 ? RECOVER_OK : RECOVER_NO;
-         }
+         if (0 < remove_any_file (file_name, ORDINARY_REMOVE_OPTION))
+           return RECOVER_OK;
+         break;

 
        case UNLINK_FIRST_OLD_FILES:
          break;
 
        case UNLINK_FIRST_OLD_FILES:
          break;


@@ -623,19 +644,20 @@ maybe_recoverable (char *file_name, bool *interdir_made)
 
     case ENOENT:
       /* Attempt creating missing intermediate directories.  */
 
     case ENOENT:
       /* Attempt creating missing intermediate directories.  */

-      if (! make_directories (file_name))
+      if (make_directories (file_name))

        {
        {

-         errno = ENOENT;
-         return RECOVER_NO;
+         *interdir_made = true;
+         return RECOVER_OK;

        }
        }

-      *interdir_made = true;
-      return RECOVER_OK;
+      break;

 
     default:
       /* Just say we can't do anything about it...  */
 
     default:
       /* Just say we can't do anything about it...  */

-
-      return RECOVER_NO;
+      break;

     }
     }

+
+  errno = e;
+  return RECOVER_NO;

 }
 
 /* Fix the statuses of all directories whose statuses need fixing, and
 }
 
 /* Fix the statuses of all directories whose statuses need fixing, and


@@ -769,7 +791,7 @@ extract_dir (char *file_name, int typeflag)
              || old_files_option == OVERWRITE_OLD_FILES))
        {
          struct stat st;
              || old_files_option == OVERWRITE_OLD_FILES))
        {
          struct stat st;

-         if (fstatat (chdir_fd, file_name, &st, 0) == 0)
+         if (deref_stat (file_name, &st) == 0)

            {
              current_mode = st.st_mode;
              current_mode_mask = ALL_MODE_BITS;
            {
              current_mode = st.st_mode;
              current_mode_mask = ALL_MODE_BITS;


@@ -787,7 +809,7 @@ extract_dir (char *file_name, int typeflag)
          errno = EEXIST;
        }
 
          errno = EEXIST;
        }
 

-      switch (maybe_recoverable (file_name, &interdir_made))
+      switch (maybe_recoverable (file_name, false, &interdir_made))

        {
        case RECOVER_OK:
          continue;
        {
        case RECOVER_OK:
          continue;


@@ -823,8 +845,11 @@ open_output_file (char const *file_name, int typeflag, mode_t mode,
 {
   int fd;
   bool overwriting_old_files = old_files_option == OVERWRITE_OLD_FILES;
 {
   int fd;
   bool overwriting_old_files = old_files_option == OVERWRITE_OLD_FILES;

-  int openflag = (O_WRONLY | O_BINARY | O_CREAT
-                 | (overwriting_old_files ? O_TRUNC : O_EXCL));
+  int openflag = (O_WRONLY | O_BINARY | O_CLOEXEC | O_NOCTTY | O_NONBLOCK
+                 | O_CREAT
+                 | (overwriting_old_files
+                    ? O_TRUNC | (dereference_option ? 0 : O_NOFOLLOW)
+                    : O_EXCL));

 
   if (typeflag == CONTTYPE)
     {
 
   if (typeflag == CONTTYPE)
     {


@@ -898,21 +923,19 @@ extract_file (char *file_name, int typeflag)
     }
   else
     {
     }
   else
     {

-      int recover = RECOVER_NO;
-      do
-       fd = open_output_file (file_name, typeflag, mode,
-                              &current_mode, &current_mode_mask);
-      while (fd < 0
-            && (recover = maybe_recoverable (file_name, &interdir_made))
-                == RECOVER_OK);
-
-      if (fd < 0)
+      while ((fd = open_output_file (file_name, typeflag, mode,
+                                    &current_mode, &current_mode_mask))
+            < 0)

        {
        {

-         skip_member ();
-         if (recover == RECOVER_SKIP)
-           return 0;
-         open_error (file_name);
-         return 1;
+         int recover = maybe_recoverable (file_name, true, &interdir_made);
+         if (recover != RECOVER_OK)
+           {
+             skip_member ();
+             if (recover == RECOVER_SKIP)
+               return 0;
+             open_error (file_name);
+             return 1;
+           }

        }
     }
 
        }
     }
 


@@ -994,7 +1017,7 @@ 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)
     {
 
   while ((fd = openat (chdir_fd, file_name, O_WRONLY | O_CREAT | O_EXCL, 0)) < 0)
     {

-      switch (maybe_recoverable (file_name, interdir_made))
+      switch (maybe_recoverable (file_name, false, interdir_made))

        {
        case RECOVER_OK:
          continue;
        {
        case RECOVER_OK:
          continue;


@@ -1106,7 +1129,8 @@ extract_link (char *file_name, int typeflag)
 
       errno = e;
     }
 
       errno = e;
     }

-  while ((rc = maybe_recoverable (file_name, &interdir_made)) == RECOVER_OK);
+  while ((rc = maybe_recoverable (file_name, false, &interdir_made))
+        == RECOVER_OK);

 
   if (rc == RECOVER_SKIP)
     return 0;
 
   if (rc == RECOVER_SKIP)
     return 0;


@@ -1130,7 +1154,7 @@ extract_symlink (char *file_name, int typeflag)
     return create_placeholder_file (file_name, true, &interdir_made);
 
   while (symlinkat (current_stat_info.link_name, chdir_fd, file_name) != 0)
     return create_placeholder_file (file_name, true, &interdir_made);
 
   while (symlinkat (current_stat_info.link_name, chdir_fd, file_name) != 0)

-    switch (maybe_recoverable (file_name, &interdir_made))
+    switch (maybe_recoverable (file_name, false, &interdir_made))

       {
       case RECOVER_OK:
        continue;
       {
       case RECOVER_OK:
        continue;


@@ -1171,7 +1195,7 @@ extract_node (char *file_name, int typeflag)
 
   while (mknodat (chdir_fd, file_name, mode, current_stat_info.stat.st_rdev)
         != 0)
 
   while (mknodat (chdir_fd, file_name, mode, current_stat_info.stat.st_rdev)
         != 0)

-    switch (maybe_recoverable (file_name, &interdir_made))
+    switch (maybe_recoverable (file_name, false, &interdir_made))

       {
       case RECOVER_OK:
        continue;
       {
       case RECOVER_OK:
        continue;


@@ -1200,7 +1224,7 @@ extract_fifo (char *file_name, int typeflag)
                 & ~ (0 < same_owner_option ? S_IRWXG | S_IRWXO : 0));
 
   while (mkfifoat (chdir_fd, file_name, mode) != 0)
                 & ~ (0 < same_owner_option ? S_IRWXG | S_IRWXO : 0));
 
   while (mkfifoat (chdir_fd, file_name, mode) != 0)

-    switch (maybe_recoverable (file_name, &interdir_made))
+    switch (maybe_recoverable (file_name, false, &interdir_made))

       {
       case RECOVER_OK:
        continue;
       {
       case RECOVER_OK:
        continue;


@@ -1348,7 +1372,7 @@ prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun)
       break;
 
     case KEEP_NEWER_FILES:
       break;
 
     case KEEP_NEWER_FILES:

-      if (file_newer_p (file_name, &current_stat_info))
+      if (file_newer_p (file_name, 0, &current_stat_info))

        {
          WARNOPT (WARN_IGNORE_NEWER,
                   (0, 0, _("Current %s is newer or same age"),
        {
          WARNOPT (WARN_IGNORE_NEWER,
                   (0, 0, _("Current %s is newer or same age"),

diff --git a/src/incremen.c b/src/incremen.c
index 4d86ed791c88d57b40e4a7fe705f4d711eb85b1a..628ff296dc13036c7d22f3271a19b700ca1c1991 100644 (file)
--- a/src/incremen.c
+++ b/src/incremen.c
@@ -408,7 +408,7 @@ update_parent_directory (struct tar_stat_info *parent)
   if (directory)
     {
       struct stat st;
   if (directory)
     {
       struct stat st;

-      if (fstatat (parent->fd, ".", &st, fstatat_flags) != 0)
+      if (fstat (parent->fd, &st) != 0)

        stat_diag (directory->name);
       else
        directory->mtime = get_stat_mtime (&st);
        stat_diag (directory->name);
       else
        directory->mtime = get_stat_mtime (&st);


@@ -1668,7 +1668,7 @@ try_purge_directory (char const *directory_name)
        free (p);
       p = new_name (directory_name, cur);
 
        free (p);
       p = new_name (directory_name, cur);
 

-      if (deref_stat (false, p, &st))
+      if (deref_stat (p, &st) != 0)

        {
          if (errno != ENOENT) /* FIXME: Maybe keep a list of renamed
                                  dirs and check it here? */
        {
          if (errno != ENOENT) /* FIXME: Maybe keep a list of renamed
                                  dirs and check it here? */

diff --git a/src/misc.c b/src/misc.c
index d94791f66a4f357d0fe542cc6dcd15b5bd197de2..763c661e9ca704d6193633baaa3020628d217110 100644 (file)
--- a/src/misc.c
+++ b/src/misc.c
@@ -544,7 +544,7 @@ maybe_backup_file (const char *file_name, bool this_is_the_archive)
   if (this_is_the_archive && _remdev (file_name))
     return true;
 
   if (this_is_the_archive && _remdev (file_name))
     return true;
 

-  if (fstatat (chdir_fd, file_name, &file_stat, 0))
+  if (deref_stat (file_name, &file_stat) != 0)

     {
       if (errno == ENOENT)
        return true;
     {
       if (errno == ENOENT)
        return true;


@@ -608,24 +608,24 @@ undo_last_backup (void)
     }
 }
 
     }
 }
 

-/* Depending on DEREF, apply either stat or lstat to (NAME, BUF).  */
+/* Apply either stat or lstat to (NAME, BUF), depending on the
+   presence of the --dereference option.  NAME is relative to the
+   most-recent argument to chdir_do.  */

 int
 int

-deref_stat (bool deref, char const *name, struct stat *buf)
+deref_stat (char const *name, struct stat *buf)

 {
 {

-  return fstatat (chdir_fd, name, buf, deref ? 0 : AT_SYMLINK_NOFOLLOW);
+  return fstatat (chdir_fd, name, buf, fstatat_flags);

 }
 
 /* Set FD's (i.e., assuming the working directory is PARENTFD, FILE's)
 }
 
 /* Set FD's (i.e., assuming the working directory is PARENTFD, FILE's)

-   access time to ATIME.  ATFLAG controls symbolic-link following, in
-   the style of openat.  */
+   access time to ATIME.  */

 int
 int

-set_file_atime (int fd, int parentfd, char const *file, struct timespec atime,
-               int atflag)
+set_file_atime (int fd, int parentfd, char const *file, struct timespec atime)

 {
   struct timespec ts[2];
   ts[0] = atime;
   ts[1].tv_nsec = UTIME_OMIT;
 {
   struct timespec ts[2];
   ts[0] = atime;
   ts[1].tv_nsec = UTIME_OMIT;

-  return fdutimensat (fd, parentfd, file, ts, atflag);
+  return fdutimensat (fd, parentfd, file, ts, fstatat_flags);

 }
 
 /* A description of a working directory.  */
 }
 
 /* A description of a working directory.  */

diff --git a/src/names.c b/src/names.c
index 88d8be2cfeccac8e3d9ade871733a8a82b412e8b..6e214bfa71e5d0c7854618288ecd8f504078359b 100644 (file)
--- a/src/names.c
+++ b/src/names.c
@@ -981,7 +981,7 @@ collect_and_sort_names (void)
 
       tar_stat_init (&st);
 
 
       tar_stat_init (&st);
 

-      if (deref_stat (dereference_option, name->name, &st.stat) != 0)
+      if (deref_stat (name->name, &st.stat) != 0)

        {
          stat_diag (name->name);
          continue;
        {
          stat_diag (name->name);
          continue;


@@ -1159,7 +1159,7 @@ register_individual_file (char const *name)
 {
   struct stat st;
 
 {
   struct stat st;
 

-  if (deref_stat (dereference_option, name, &st) != 0)
+  if (deref_stat (name, &st) != 0)

     return; /* Will be complained about later */
   if (S_ISDIR (st.st_mode))
     return;
     return; /* Will be complained about later */
   if (S_ISDIR (st.st_mode))
     return;

diff --git a/src/tar.c b/src/tar.c
index 6fd117c636702f564511be0d3c7c4876b849efdb..d80a10f03613e46b8c51430b6183ff8ff800cd82 100644 (file)
--- a/src/tar.c
+++ b/src/tar.c
@@ -1014,7 +1014,7 @@ get_date_or_file (struct tar_args *args, const char *option,
       || *str == '.')
     {
       struct stat st;
       || *str == '.')
     {
       struct stat st;

-      if (deref_stat (dereference_option, str, &st) != 0)
+      if (stat (str, &st) != 0)

        {
          stat_error (str);
          USAGE_ERROR ((0, 0, _("Date sample file not found")));
        {
          stat_error (str);
          USAGE_ERROR ((0, 0, _("Date sample file not found")));

diff --git a/src/update.c b/src/update.c
index de2786df3e86efc748692f0f5a6d585f220fd674..69fa5924b1b64e921e69492333142959926ff39b 100644 (file)
--- a/src/update.c
+++ b/src/update.c
@@ -138,8 +138,7 @@ update_archive (void)
                struct stat s;
 
                chdir_do (name->change_dir);
                struct stat s;
 
                chdir_do (name->change_dir);

-               if (deref_stat (dereference_option,
-                               current_stat_info.file_name, &s) == 0)
+               if (deref_stat (current_stat_info.file_name, &s) == 0)

                  {
                    if (S_ISDIR (s.st_mode))
                      {
                  {
                    if (S_ISDIR (s.st_mode))
                      {

diff --git a/tests/Makefile.am b/tests/Makefile.am
index d378a376e9894d93e19bb6856b6c75386d4cdc3d..34be61750376c1311ee077734abb32a0142a75ef 100644 (file)
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -79,6 +79,7 @@ TESTSUITE_AT = \
  extrac10.at\
  extrac11.at\
  extrac12.at\
  extrac10.at\
  extrac11.at\
  extrac12.at\

+ extrac13.at\

  filerem01.at\
  filerem02.at\
  gzip.at\
  filerem01.at\
  filerem02.at\
  gzip.at\

diff --git a/tests/extrac13.at b/tests/extrac13.at
new file mode 100644 (file)
index 0000000..2f950cb
--- /dev/null
+++ b/tests/extrac13.at
@@ -0,0 +1,53 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+
+# Test suite for GNU tar.
+# Copyright (C) 2010 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
+
+# Check that 'tar' normally does follow symbolic links when extracting,
+# unless --dereference is specified.
+
+AT_SETUP([extract over symlinks])
+AT_KEYWORDS([extract extrac13])
+
+AT_TAR_CHECK([
+mkdir src dst1 dst2 dst3
+echo file1 >src/file1
+ln -s target1 dst1/file1
+echo target1 >dst1/target1
+echo target1 >target1
+
+tar -cf archive.tar -C src . &&
+tar -xf archive.tar -C dst1 &&
+diff -c src/file1 dst1/file1 &&
+diff -c target1 dst1/target1
+
+ln -s target1 dst2/file1
+echo target1 >dst2/target1
+tar --overwrite -xf archive.tar -C dst2 &&
+diff -c src/file1 dst2/file1 &&
+diff -c target1 dst2/target1
+
+ln -s target1 dst3/file1
+echo target1 >dst3/target1
+tar --overwrite -xhf archive.tar -C dst3 &&
+diff -c src/file1 dst3/file1 &&
+diff -c src/file1 dst3/target1
+],
+[0],[],[],[],[],[gnu])
+
+AT_CLEANUP

diff --git a/tests/testsuite.at b/tests/testsuite.at
index dc7a603aae72d2a40f5c9c62197fb182ffbb49a4..8d76887705aa1042f00b05e6bc8bb449f22e3676 100644 (file)
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -151,6 +151,7 @@ m4_include([extrac09.at])
 m4_include([extrac10.at])
 m4_include([extrac11.at])
 m4_include([extrac12.at])
 m4_include([extrac10.at])
 m4_include([extrac11.at])
 m4_include([extrac12.at])

+m4_include([extrac13.at])

 
 m4_include([label01.at])
 m4_include([label02.at])
 
 m4_include([label01.at])
 m4_include([label02.at])