1015-gnttab-disable-grant-tables-v2-by-default.patch

From f2ce35f0da8dace989b1fd1ea37833eacbca4640 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Wed, 25 Aug 2021 02:41:51 +0200
Subject: [PATCH] gnttab: disable grant tables v2 by default
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They are not used anywhere, and are significant attack surface.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
---
 xen/common/grant_table.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/common/grant_table.c b/xen/common/grant_table.c
index ebe2d2a3ceec..632c4c307c33 100644
--- a/xen/common/grant_table.c
+++ b/xen/common/grant_table.c
@@ -179,7 +179,7 @@ static int cf_check parse_gnttab_max_maptrack_frames(const char *arg)
 }
 
 #ifndef GNTTAB_MAX_VERSION
-#define GNTTAB_MAX_VERSION 2
+#define GNTTAB_MAX_VERSION 1
 #endif
 
 unsigned int __read_mostly opt_gnttab_max_version = GNTTAB_MAX_VERSION;
-- 
2.44.0