From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Sun, 26 Dec 2010 20:15:31 +0000 (+0100)
Subject: 	Handling of files of unknown size is currently limited. They can't be
X-Git-Tag: 1.99~275
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0b2db94300dca2b7597e3fbf6ade3a1cebd72c19;p=thirdparty%2Fgrub.git

	Handling of files of unknown size is currently limited. They can't be
	used e.g. for initrd or modules. Moreover gzip handling of not
	easily seekable files is buggy. Disable unknown file size for now. May
	be inefficient but works.

	* grub-core/io/gzio.c (test_header): Always retrieve the file size.
	* grub-core/io/xzio.c (grub_xzio_open): Likewise.
---

diff --git a/ChangeLog b/ChangeLog
index 80f5ef568..0c701a342 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2010-12-26  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	Handling of files of unknown size is currently limited. They can't be
+	used e.g. for initrd or modules. Moreover gzip handling of not
+	easily seekable files is buggy. Disable unknown file size for now. May
+	be inefficient but works.
+
+	* grub-core/io/gzio.c (test_header): Always retrieve the file size.
+	* grub-core/io/xzio.c (grub_xzio_open): Likewise.
+
 2010-12-25  Mirko Parthey <mirko.parthey@informatik.tu-chemnitz.de>
 
 	* grub-core/boot/i386/pc/boot.S: Fix %es:%bx pointing to nowhere on
diff --git a/grub-core/io/gzio.c b/grub-core/io/gzio.c
index 43b67c373..f563d7b92 100644
--- a/grub-core/io/gzio.c
+++ b/grub-core/io/gzio.c
@@ -212,19 +212,18 @@ test_header (grub_file_t file)
 
   gzio->data_offset = grub_file_tell (gzio->file);
 
-  grub_file_seek (gzio->file, grub_file_size (gzio->file) - 4);
-
-  if (grub_file_seekable (gzio->file))
-    {
-      if (grub_file_read (gzio->file, &orig_len, 4) != 4)
-	{
-	  grub_error (GRUB_ERR_BAD_FILE_TYPE, "unsupported gzip format");
-	  return 0;
-	}
-    }
-  /* FIXME: this does not handle files whose original size is over 4GB.
-     But how can we know the real original size?  */
-  file->size = grub_le_to_cpu32 (orig_len);
+  /* FIXME: don't do this on not easily seekable files.  */
+  {
+    grub_file_seek (gzio->file, grub_file_size (gzio->file) - 4);
+    if (grub_file_read (gzio->file, &orig_len, 4) != 4)
+      {
+	grub_error (GRUB_ERR_BAD_FILE_TYPE, "unsupported gzip format");
+	return 0;
+      }
+    /* FIXME: this does not handle files whose original size is over 4GB.
+       But how can we know the real original size?  */
+    file->size = grub_le_to_cpu32 (orig_len);
+  }
 
   initialize_tables (file);
 
diff --git a/grub-core/io/xzio.c b/grub-core/io/xzio.c
index 1a22bdc70..37be1790f 100644
--- a/grub-core/io/xzio.c
+++ b/grub-core/io/xzio.c
@@ -222,7 +222,8 @@ grub_xzio_open (grub_file_t io)
   xzio->buf.out_pos = 0;
   xzio->buf.out_size = XZBUFSIZ;
 
-  if (!test_header (file) || !(grub_file_seekable (io) && test_footer (file)))
+  /* FIXME: don't test footer on not easily seekable files.  */
+  if (!test_header (file) || !test_footer (file))
     {
       grub_errno = GRUB_ERR_NONE;
       grub_file_seek (io, 0);