From: Heinrich Schuchardt <xypron.glpk@gmx.de>
Date: Mon, 17 Dec 2018 21:00:24 +0000 (+0100)
Subject: grub-core/loader/efi/fdt.c: Do not copy random memory
X-Git-Tag: grub-2.04-rc1~75
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ad0ea7c444234ca519a3b528ddc70fff45810e25;p=thirdparty%2Fgrub.git

grub-core/loader/efi/fdt.c: Do not copy random memory

We should not try to copy any memory area which is outside of the original
fdt. If this extra memory is controlled by a hypervisor this might end
with a crash.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---

diff --git a/grub-core/loader/efi/fdt.c b/grub-core/loader/efi/fdt.c
index a18ca8ccb..ee9c5592c 100644
--- a/grub-core/loader/efi/fdt.c
+++ b/grub-core/loader/efi/fdt.c
@@ -66,7 +66,7 @@ grub_fdt_load (grub_size_t additional_size)
 
   if (raw_fdt)
     {
-      grub_memmove (fdt, raw_fdt, size);
+      grub_memmove (fdt, raw_fdt, size - additional_size);
       grub_fdt_set_totalsize (fdt, size);
     }
   else