(flush_write): Limit filenames

[chaz/tar] / src / buffer.c

diff --git a/src/buffer.c b/src/buffer.c
index 80bbe829b4d031ed0ea7b47a527f818515550e4b..d7c6844c4fd9da9eb8873d94991334f6ad4397ce 100644 (file)
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -40,6 +40,7 @@
 
 static tarlong prev_written;   /* bytes written on previous volumes */
 static tarlong bytes_written;  /* bytes written on this volume */
+static void *record_buffer;    /* allocated memory */
 
 /* FIXME: The following variables should ideally be static to this
    module.  However, this cannot be done yet.  The cleanup continues!  */
@@ -270,17 +271,12 @@ open_archive (enum access_mode wanted_access)
   save_name = 0;
   real_s_name = 0;
 
+  record_start =
+    page_aligned_alloc (&record_buffer,
+                       (record_size
+                        + (multi_volume_option ? 2 * BLOCKSIZE : 0)));
   if (multi_volume_option)
-    {
-      record_start = valloc (record_size + (2 * BLOCKSIZE));
-      if (record_start)
-       record_start += 2;
-    }
-  else
-    record_start = valloc (record_size);
-  if (!record_start)
-    FATAL_ERROR ((0, 0, _("Cannot allocate memory for blocking factor %d"),
-                 blocking_factor));
+    record_start += 2;
 
   current_block = record_start;
   record_end = record_start + blocking_factor;
@@ -514,13 +510,18 @@ flush_write (void)
       if (volume_label_option)
        record_start++;
 
+      if (strlen (real_s_name) > NAME_FIELD_SIZE)
+       FATAL_ERROR ((0, 0,
+                     _("%s: file name too long to be stored in a GNU multivolume header"),
+                     quotearg_colon (real_s_name)));
+      
       memset (record_start, 0, BLOCKSIZE);
 
       /* FIXME: Michael P Urban writes: [a long name file] is being written
         when a new volume rolls around [...]  Looks like the wrong value is
         being preserved in real_s_name, though.  */
 
-      strcpy (record_start->header.name, real_s_name);
+      strncpy (record_start->header.name, real_s_name, NAME_FIELD_SIZE);
       record_start->header.typeflag = GNUTYPE_MULTIVOL;
       OFF_TO_CHARS (real_s_sizeleft, record_start->header.size);
       OFF_TO_CHARS (real_s_totsize - real_s_sizeleft,
@@ -767,7 +768,7 @@ flush_read (void)
        {
          uintmax_t s1, s2;
          if (cursor->header.typeflag != GNUTYPE_MULTIVOL
-             || strcmp (cursor->header.name, real_s_name))
+             || strncmp (cursor->header.name, real_s_name, NAME_FIELD_SIZE))
            {
              WARN ((0, 0, _("%s is not continued on this volume"),
                     quote (real_s_name)));
@@ -946,7 +947,7 @@ close_archive (void)
     free (save_name);
   if (real_s_name)
     free (real_s_name);
-  free (multi_volume_option ? record_start - 2 : record_start);
+  free (record_buffer);
 }
 
 /* Called to initialize the global volume number.  */