From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752251AbdIIWmw (ORCPT ); Sat, 9 Sep 2017 18:42:52 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:41495 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751873AbdIIWYn (ORCPT ); Sat, 9 Sep 2017 18:24:43 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "=?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?=" , "Dan Carpenter" , "Paolo Bonzini" , "David Hildenbrand" Date: Sat, 09 Sep 2017 22:47:39 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 037/106] KVM: x86: zero base3 of unusable segments In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.93-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Radim Krčmář commit f0367ee1d64d27fa08be2407df5c125442e885e3 upstream. Static checker noticed that base3 could be used uninitialized if the segment was not present (useable). Random stack values probably would not pass VMCS entry checks. Reported-by: Dan Carpenter Fixes: 1aa366163b8b ("KVM: x86 emulator: consolidate segment accessors") Reviewed-by: Paolo Bonzini Reviewed-by: David Hildenbrand Signed-off-by: Radim Krčmář Signed-off-by: Ben Hutchings --- arch/x86/kvm/x86.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4613,6 +4613,8 @@ static bool emulator_get_segment(struct if (var.unusable) { memset(desc, 0, sizeof(*desc)); + if (base3) + *base3 = 0; return false; }