tar: don't cross struct member boundaries with OLDGNU_MAGIC

[chaz/tar] / src / create.c

diff --git a/src/create.c b/src/create.c
index 6eedb2efc6e1dafb668311d8ffe01cbd45287e40..a1e90a33679f12b0119953cbf465d64bd1e21eb5 100644 (file)
--- a/src/create.c
+++ b/src/create.c
@@ -562,7 +562,8 @@ write_gnu_long_link (struct tar_stat_info *st, const char *p, char type)
   GNAME_TO_CHARS (tmpname, header->header.gname);
   free (tmpname);
 
-  strcpy (header->header.magic, OLDGNU_MAGIC);
+  strcpy (header->buffer + offsetof (struct posix_header, magic),
+         OLDGNU_MAGIC);
   header->header.typeflag = type;
   finish_header (st, header, -1);
 
@@ -899,7 +900,8 @@ start_header (struct tar_stat_info *st)
     case OLDGNU_FORMAT:
     case GNU_FORMAT:   /*FIXME?*/
       /* Overwrite header->header.magic and header.version in one blow.  */
-      strcpy (header->header.magic, OLDGNU_MAGIC);
+      strcpy (header->buffer + offsetof (struct posix_header, magic),
+             OLDGNU_MAGIC);
       break;
 
     case POSIX_FORMAT:
@@ -1345,7 +1347,8 @@ create_archive (void)
                    {
                      if (! st.orig_file_name)
                        {
-                         int fd = open (p->name, open_searchdir_flags);
+                         int fd = openat (chdir_fd, p->name,
+                                          open_searchdir_flags);
                          if (fd < 0)
                            {
                              open_diag (p->name);
@@ -1549,7 +1552,7 @@ subfile_open (struct tar_stat_info const *dir, char const *file, int flags)
       gettext ("");
     }
 
-  while ((fd = openat (dir ? dir->fd : AT_FDCWD, file, flags)) < 0
+  while ((fd = openat (dir ? dir->fd : chdir_fd, file, flags)) < 0
         && open_failure_recover (dir))
     continue;
   return fd;
@@ -1580,7 +1583,8 @@ restore_parent_fd (struct tar_stat_info const *st)
 
       if (parentfd < 0)
        {
-         int origfd = open (parent->orig_file_name, open_searchdir_flags);
+         int origfd = openat (chdir_fd, parent->orig_file_name,
+                              open_searchdir_flags);
          if (0 <= origfd)
            {
              if (fstat (parentfd, &parentstat) == 0
@@ -1615,7 +1619,7 @@ dump_file0 (struct tar_stat_info *st, char const *name, char const *p)
   bool is_dir;
   struct tar_stat_info const *parent = st->parent;
   bool top_level = ! parent;
-  int parentfd = top_level ? AT_FDCWD : parent->fd;
+  int parentfd = top_level ? chdir_fd : parent->fd;
   void (*diag) (char const *) = 0;
 
   if (interactive_option && !confirm ("add", p))
@@ -1723,7 +1727,7 @@ dump_file0 (struct tar_stat_info *st, char const *name, char const *p)
          ok = dump_dir (st);
 
          fd = st->fd;
-         parentfd = top_level ? AT_FDCWD : parent->fd;
+         parentfd = top_level ? chdir_fd : parent->fd;
        }
       else
        {
@@ -1793,7 +1797,7 @@ 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_file_atime (fd, p, st->atime, fstatat_flags) != 0)
+                  && set_file_atime (fd, parentfd, name, st->atime) != 0)
            utime_error (p);
        }