From a0e4b0eb6fb0eedc3250857a29322ffaf6cedea6 Mon Sep 17 00:00:00 2001
Message-Id: <a0e4b0eb6fb0eedc3250857a29322ffaf6cedea6.1363792519.git.minovotn@redhat.com>
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References: <76f48f7faa6ca5742e3972153b490d00e74d5a93.1363792519.git.minovotn@redhat.com>
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 20 Mar 2013 11:25:51 +0100
Subject: [PATCH 4/4] do not #GP on unaligned MSR_KVM_SYSTEM_TIME write

RH-Author: Gleb Natapov <gleb@redhat.com>
Message-id: <20130320112551.GH3889@redhat.com>
Patchwork-id: 49747
O-Subject: [PATCH RHEL5.10 RHEL5.9.z] do not #GP on unaligned MSR_KVM_SYSTEM_TIME write
Bugzilla:
RH-Acked-by: Petr Matousek <pmatouse@redhat.com>
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

RHEL5.9.z BZ: 917018
RHEL5.10 BZ: 917019
Upstream commit: c300aa64ddf57d9c5d9c898a64b36877345dd4a9

Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
This patch goes on top of "KVM: Fix for buffer overflow
in handling of MSR_KVM_SYSTEM_TIME (CVE-2013-1796)" the actually code
that was committed upstream was different so this patch makes rhel to be
the same as upstream.

--
			Gleb.

Signed-off-by: Michal Novotny <minovotn@redhat.com>
---
 arch/x86/kvm/x86.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e2d9bd0..525ccee 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -852,7 +852,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 		/* Check that the address is 32-byte aligned. */
 		if (vcpu->arch.time_offset &
 				(sizeof(struct pvclock_vcpu_time_info) - 1))
-			return 1;
+			break;
 
 		vcpu->arch.time_page =
 				gfn_to_page(vcpu->kvm, data >> PAGE_SHIFT);
-- 
1.7.11.7