lkml.org 
[lkml]   [2015]   [Feb]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.12 101/122] KVM: x86: Sysexit emulation does not mask RIP/RSP
Date
From: Nadav Amit <namit@cs.technion.ac.il>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit bf0b682c9b6a6d6d54adf439bfe953feef7be2e8 upstream.

If the operand size is not 64-bit, then the sysexit instruction should assign
ECX to RSP and EDX to RIP. The current code assigns the full 64-bits.

Fix it by masking.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/x86/kvm/emulate.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index d28104924255..8ab43ac68f06 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2372,6 +2372,8 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt)
if ((msr_data & 0xfffc) == 0x0)
return emulate_gp(ctxt, 0);
ss_sel = (u16)(msr_data + 24);
+ rcx = (u32)rcx;
+ rdx = (u32)rdx;
break;
case X86EMUL_MODE_PROT64:
cs_sel = (u16)(msr_data + 32);
--
2.2.2


\
 
 \ /
  Last update: 2015-02-17 13:01    [W:0.318 / U:0.912 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site