[1886] 2008-10-05 Hans Lambermont <[email protected]>

Revision: 1886
          http://svn.sv.gnu.org/viewvc/?view=rev&root=grub&revision=1886
Author:   robertmh
Date:     2008-10-05 10:51:23 +0000 (Sun, 05 Oct 2008)

Log Message:
-----------
2008-10-05  Hans Lambermont  <[email protected]>

        * disk/lvm.c (grub_lvm_scan_device): Allocate buffer space for the
        circular metadata worst case scenario. If the metadata is circular
        then copy the wrap in place.
        * include/grub/lvm.h: Add GRUB_LVM_MDA_HEADER_SIZE, from the LVM2
        project lib/format_text/layout.h
        Circular metadata bug found and patch debugged by Jan Derk Gerlings.

Modified Paths:
--------------
    trunk/grub2/ChangeLog
    trunk/grub2/disk/lvm.c
    trunk/grub2/include/grub/lvm.h

Modified: trunk/grub2/ChangeLog
===================================================================
--- trunk/grub2/ChangeLog	2008-10-03 18:05:52 UTC (rev 1885)
+++ trunk/grub2/ChangeLog	2008-10-05 10:51:23 UTC (rev 1886)
@@ -1,3 +1,12 @@
+2008-10-05  Hans Lambermont  <[email protected]>
+
+	* disk/lvm.c (grub_lvm_scan_device): Allocate buffer space for the
+	circular metadata worst case scenario. If the metadata is circular
+	then copy the wrap in place.
+	* include/grub/lvm.h: Add GRUB_LVM_MDA_HEADER_SIZE, from the LVM2
+	project lib/format_text/layout.h
+	Circular metadata bug found and patch debugged by Jan Derk Gerlings.
+
 2008-10-03  Felix Zielcke  <[email protected]>
 
 	* util/i386/pc/grub-install.in: Source grub-mkconfig_lib instead of update-grub_lib.

Modified: trunk/grub2/disk/lvm.c
===================================================================
--- trunk/grub2/disk/lvm.c	2008-10-03 18:05:52 UTC (rev 1885)
+++ trunk/grub2/disk/lvm.c	2008-10-05 10:51:23 UTC (rev 1886)
@@ -281,7 +281,8 @@
       goto fail;
     }
 
-  metadatabuf = grub_malloc (mda_size);
+  /* Allocate buffer space for the circular worst-case scenario. */
+  metadatabuf = grub_malloc (2 * mda_size);
   if (! metadatabuf)
     goto fail;
 
@@ -300,6 +301,16 @@
     }
 
   rlocn = mdah->raw_locns;
+  if (grub_le_to_cpu64 (rlocn->offset) + grub_le_to_cpu64 (rlocn->size) >
+      grub_le_to_cpu64 (mdah->size))
+    {
+      /* Metadata is circular. Copy the wrap in place. */
+      grub_memcpy (metadatabuf + mda_size,
+                   metadatabuf + GRUB_LVM_MDA_HEADER_SIZE,
+                   grub_le_to_cpu64 (rlocn->offset) +
+                   grub_le_to_cpu64 (rlocn->size) -
+                   grub_le_to_cpu64 (mdah->size));
+    }
   p = q = metadatabuf + grub_le_to_cpu64 (rlocn->offset);
 
   while (*q != ' ' && q < metadatabuf + mda_size)

Modified: trunk/grub2/include/grub/lvm.h
===================================================================
--- trunk/grub2/include/grub/lvm.h	2008-10-03 18:05:52 UTC (rev 1885)
+++ trunk/grub2/include/grub/lvm.h	2008-10-05 10:51:23 UTC (rev 1886)
@@ -103,6 +103,7 @@
 
 #define GRUB_LVM_FMTT_MAGIC "\040\114\126\115\062\040\170\133\065\101\045\162\060\116\052\076"
 #define GRUB_LVM_FMTT_VERSION 1
+#define GRUB_LVM_MDA_HEADER_SIZE 512
 
 /* On disk */
 struct grub_lvm_raw_locn {