Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751119AbaKKL5P (ORCPT ); Tue, 11 Nov 2014 06:57:15 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:57348 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753803AbaKKLJu (ORCPT ); Tue, 11 Nov 2014 06:09:50 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Nadav Amit , Paolo Bonzini , Luis Henriques Subject: [PATCH 3.16.y-ckt 051/170] KVM: x86: Fix wrong masking on relative jump/call Date: Tue, 11 Nov 2014 11:06:50 +0000 Message-Id: <1415704129-12709-52-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1415704129-12709-1-git-send-email-luis.henriques@canonical.com> References: <1415704129-12709-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Nadav Amit commit 05c83ec9b73c8124555b706f6af777b10adf0862 upstream. Relative jumps and calls do the masking according to the operand size, and not according to the address size as the KVM emulator does today. This patch fixes KVM behavior. Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini Signed-off-by: Luis Henriques --- arch/x86/kvm/emulate.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 2d3b8d0efa0f..601188b8c915 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -499,11 +499,6 @@ static void rsp_increment(struct x86_emulate_ctxt *ctxt, int inc) masked_increment(reg_rmw(ctxt, VCPU_REGS_RSP), stack_mask(ctxt), inc); } -static inline void jmp_rel(struct x86_emulate_ctxt *ctxt, int rel) -{ - register_address_increment(ctxt, &ctxt->_eip, rel); -} - static u32 desc_limit_scaled(struct desc_struct *desc) { u32 limit = get_desc_limit(desc); @@ -577,6 +572,28 @@ static int emulate_nm(struct x86_emulate_ctxt *ctxt) return emulate_exception(ctxt, NM_VECTOR, 0, false); } +static inline void assign_eip_near(struct x86_emulate_ctxt *ctxt, ulong dst) +{ + switch (ctxt->op_bytes) { + case 2: + ctxt->_eip = (u16)dst; + break; + case 4: + ctxt->_eip = (u32)dst; + break; + case 8: + ctxt->_eip = dst; + break; + default: + WARN(1, "unsupported eip assignment size\n"); + } +} + +static inline void jmp_rel(struct x86_emulate_ctxt *ctxt, int rel) +{ + assign_eip_near(ctxt, ctxt->_eip + rel); +} + static u16 get_segment_selector(struct x86_emulate_ctxt *ctxt, unsigned seg) { u16 selector; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/