From: Kees Cook <kees.cook@canonical.com>
To: x86@kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 3/4] x86: call verify_cpu during 32bit CPU startup
Date: Tue, 9 Nov 2010 10:15:25 -0800 [thread overview]
Message-ID: <20101109181525.GH5876@outflux.net> (raw)
In-Reply-To: <20101109181157.GE5876@outflux.net>
The XD_DISABLE-clearing side-effect needs to happen on 32bit CPU
start-up as well.
Signed-off-by: Kees Cook <kees.cook@canonical.com>
---
arch/x86/kernel/head_32.S | 6 ++++++
arch/x86/kernel/verify_cpu.S | 1 +
2 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index bcece91..fdaea52 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -314,6 +314,10 @@ ENTRY(startup_32_smp)
subl $0x80000001, %eax
cmpl $(0x8000ffff-0x80000001), %eax
ja 6f
+
+ /* Clear bogus XD_DISABLE bits */
+ call verify_cpu
+
mov $0x80000001, %eax
cpuid
/* Execute Disable bit supported? */
@@ -609,6 +613,8 @@ ignore_int:
#endif
iret
+#include "verify_cpu.S"
+
__REFDATA
.align 4
ENTRY(initial_code)
diff --git a/arch/x86/kernel/verify_cpu.S b/arch/x86/kernel/verify_cpu.S
index ccb4136..5644b4b 100644
--- a/arch/x86/kernel/verify_cpu.S
+++ b/arch/x86/kernel/verify_cpu.S
@@ -19,6 +19,7 @@
*
* arch/x86_64/boot/compressed/head_64.S: Boot cpu verification
* arch/x86_64/kernel/trampoline_64.S: secondary processor verfication
+ * arch/x86_64/kernel/head_32.S: processor startup
*
* verify_cpu, returns the status of longmode and SSE in register %eax.
* 0: Success 1: Failure
--
1.7.2.3
--
Kees Cook
Ubuntu Security Team
next prev parent reply other threads:[~2010-11-09 18:15 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-11-09 18:11 [Security] [PATCH v3 0/4] x86: clear XD_DISABLED flag on Intel to regain NX Kees Cook
2010-11-09 18:14 ` [PATCH 1/4] x86: rename verify_cpu_64.S to verify_cpu.S Kees Cook
2010-11-09 18:46 ` Pekka Enberg
2010-11-09 19:00 ` Kees Cook
2010-11-09 19:59 ` Pekka Enberg
2010-11-09 19:02 ` Kees Cook
2010-11-09 19:11 ` Pekka Enberg
2010-11-09 18:15 ` [PATCH 2/4] x86: clear XD_DISABLED flag on Intel to regain NX Kees Cook
2010-11-10 16:11 ` Andi Kleen
2010-11-10 16:47 ` Kees Cook
2010-11-10 17:42 ` Andi Kleen
2010-11-10 18:15 ` Kees Cook
2010-11-09 18:15 ` Kees Cook [this message]
2010-11-09 19:09 ` [PATCH 3/4] x86: call verify_cpu during 32bit CPU startup Pekka Enberg
2010-11-09 19:19 ` Kees Cook
2010-11-09 19:46 ` Pekka Enberg
2010-11-09 19:56 ` Kees Cook
2010-11-09 20:28 ` Pekka Enberg
2010-11-09 20:48 ` Kees Cook
2010-11-09 20:50 ` Pekka Enberg
2010-11-09 18:15 ` [PATCH 4/4] x86: only CPU features determine NX capabilities Kees Cook
2010-11-09 18:31 ` [Security] [PATCH v3 0/4] x86: clear XD_DISABLED flag on Intel to regain NX Alan Cox
2010-11-09 18:56 ` Kees Cook
2010-11-09 22:50 ` Alan Cox
2010-11-09 23:53 ` Kees Cook
2010-11-10 0:21 ` Alan Cox
2010-11-10 0:43 ` Kees Cook
2010-11-10 1:10 ` Kees Cook
2010-11-10 11:11 ` Alan Cox
2010-11-10 11:15 ` Ingo Molnar
2010-11-11 15:15 ` Rogier Wolff
-- strict thread matches above, loose matches on Subject: below --
2010-11-10 18:35 [Security] [PATCH v5 " Kees Cook
2010-11-10 18:35 ` [PATCH 3/4] x86: call verify_cpu during 32bit CPU startup Kees Cook
2010-11-14 6:33 ` Yinghai Lu
2010-11-09 22:17 [Security] [PATCH v4 0/4] x86: clear XD_DISABLED flag on Intel to regain NX Kees Cook
2010-11-09 22:18 ` [PATCH 3/4] x86: call verify_cpu during 32bit CPU startup Kees Cook
2010-06-19 5:50 [PATCH v2 0/4] x86: clear XD_DISABLED flag on Intel to regain NX Kees Cook
2010-06-19 5:52 ` [PATCH 3/4] x86: call verify_cpu during 32bit CPU startup Kees Cook
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