aboutsummaryrefslogtreecommitdiffstats
path: root/common/recipes-kernel/linux/linux-yocto-4.9.21/0082-module-Add-retpoline-tag-to-VERMAGIC.patch
blob: 424f3c6bee3cfe518d9cfd9e1936b54b35a93f3d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
From 134164c659e681c1ed401ddd773b12852a1b9019 Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@linux.intel.com>
Date: Tue, 16 Jan 2018 12:52:28 -0800
Subject: [PATCH 082/102] module: Add retpoline tag to VERMAGIC

commit 6cfb521ac0d5b97470883ff9b7facae264b7ab12 upstream.

Add a marker for retpoline to the module VERMAGIC. This catches the case
when a non RETPOLINE compiled module gets loaded into a retpoline kernel,
making it insecure.

It doesn't handle the case when retpoline has been runtime disabled.  Even
in this case the match of the retcompile status will be enforced.  This
implies that even with retpoline run time disabled all modules loaded need
to be recompiled.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: rusty@rustcorp.com.au
Cc: arjan.van.de.ven@intel.com
Cc: jeyu@kernel.org
Cc: torvalds@linux-foundation.org
Link: https://lkml.kernel.org/r/20180116205228.4890-1-andi@firstfloor.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/vermagic.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/linux/vermagic.h b/include/linux/vermagic.h
index 6f8fbcf..a3d0493 100644
--- a/include/linux/vermagic.h
+++ b/include/linux/vermagic.h
@@ -24,10 +24,16 @@
 #ifndef MODULE_ARCH_VERMAGIC
 #define MODULE_ARCH_VERMAGIC ""
 #endif
+#ifdef RETPOLINE
+#define MODULE_VERMAGIC_RETPOLINE "retpoline "
+#else
+#define MODULE_VERMAGIC_RETPOLINE ""
+#endif
 
 #define VERMAGIC_STRING 						\
 	UTS_RELEASE " "							\
 	MODULE_VERMAGIC_SMP MODULE_VERMAGIC_PREEMPT 			\
 	MODULE_VERMAGIC_MODULE_UNLOAD MODULE_VERMAGIC_MODVERSIONS	\
-	MODULE_ARCH_VERMAGIC
+	MODULE_ARCH_VERMAGIC						\
+	MODULE_VERMAGIC_RETPOLINE
 
-- 
2.7.4