From: Gleb Natapov <gleb@redhat.com>
To: kvm@vger.kernel.org
Cc: mtosatti@redhat.com
Subject: [PATCH 8/9] KVM: x86: fix use of uninitialized memory as segment descriptor in emulator.
Date: Mon, 21 Jan 2013 15:36:48 +0200 [thread overview]
Message-ID: <1358775409-27555-9-git-send-email-gleb@redhat.com> (raw)
In-Reply-To: <1358775409-27555-1-git-send-email-gleb@redhat.com>
If VMX reports segment as unusable, zero descriptor passed by the emulator
before returning. Such descriptor will be considered not present by the
emulator.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
arch/x86/kvm/x86.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5483228..d8a0e94 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4489,8 +4489,10 @@ static bool emulator_get_segment(struct x86_emulate_ctxt *ctxt, u16 *selector,
kvm_get_segment(emul_to_vcpu(ctxt), &var, seg);
*selector = var.selector;
- if (var.unusable)
+ if (var.unusable) {
+ memset(desc, 0, sizeof(*desc));
return false;
+ }
if (var.g)
var.limit >>= 12;
--
1.7.10.4
next prev parent reply other threads:[~2013-01-21 13:36 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-21 13:36 [PATCH 0/9] some more vmx real mode emulation fixes and cleanups Gleb Natapov
2013-01-21 13:36 ` [PATCH 1/9] KVM: VMX: remove special CPL cache access during transition to real mode Gleb Natapov
2013-01-21 13:36 ` [PATCH 2/9] KVM: VMX: reset CPL only on CS register write Gleb Natapov
2013-01-21 13:36 ` [PATCH 3/9] KVM: VMX: if unrestricted guest is enabled vcpu state is always valid Gleb Natapov
2013-01-21 13:36 ` [PATCH 4/9] KVM: VMX: remove hack that disables emulation on vcpu reset/init Gleb Natapov
2013-01-21 13:36 ` [PATCH 5/9] KVM: VMX: skip vmx->rmode.vm86_active check on cr0 write if unrestricted guest is enabled Gleb Natapov
2013-01-21 13:36 ` [PATCH 6/9] KVM: VMX: don't clobber segment AR of unusable segments Gleb Natapov
2013-01-21 13:36 ` [PATCH 7/9] KVM: VMX: rename fix_pmode_dataseg to fix_pmode_seg Gleb Natapov
2013-01-21 13:36 ` Gleb Natapov [this message]
2013-01-21 13:36 ` [PATCH 9/9] KVM: VMX: set vmx->emulation_required only when needed Gleb Natapov
2013-01-24 0:39 ` [PATCH 0/9] some more vmx real mode emulation fixes and cleanups Marcelo Tosatti
2013-01-24 23:45 ` Marcelo Tosatti
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