From patchwork Wed Jun 5 21:19:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugene Korenevsky X-Patchwork-Id: 10977925 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A892B92A for ; Wed, 5 Jun 2019 21:19:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 984C2289EB for ; Wed, 5 Jun 2019 21:19:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8C98628A71; Wed, 5 Jun 2019 21:19:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9B5B6289EB for ; Wed, 5 Jun 2019 21:19:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726738AbfFEVTW (ORCPT ); Wed, 5 Jun 2019 17:19:22 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:45126 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726510AbfFEVTW (ORCPT ); Wed, 5 Jun 2019 17:19:22 -0400 Received: by mail-lj1-f194.google.com with SMTP id m23so2680736lje.12 for ; Wed, 05 Jun 2019 14:19:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mail-followup-to:mime-version :content-disposition:user-agent; bh=Lmhd/YacZftPAqgJuqkCakUzgIJ7vNdS9G7SRVFZD28=; b=oxZJp6/6GGO1dG4JcXNE/vJjECtNblCrHQDM8IHKwbIuRtpcOYUtgYvNjUTKAMigcu /oty3n9LwyDVFCaP7gHZPSWOc3AUHf6czO36TPano/Ub2U8HHJjq3iUl5/r1esnTRX4L Ojv2Nl6pFYsCM/+4KcFtNqP2m0zup5qTaTnumEM0RlZnwkAT4r9Hzp6udK4rSWEeBd3u n3MwyoWSbPG9dIwYvStBytJORd+7Gt6ZoGFDZpIsEGCMSzLR2sqX2bZDfNDBg2ZmY+fR lu7+LS1PUXQCEXQ5iPLRrhWf2kzAo4AN76h0eeflK9Au5MNNvHgTTeJFDgtfCEWbcDCv xYLg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id :mail-followup-to:mime-version:content-disposition:user-agent; bh=Lmhd/YacZftPAqgJuqkCakUzgIJ7vNdS9G7SRVFZD28=; b=DEp3qlxChyA/xnkrsMgOP2iVl4W0T7XOhOs0Uc4cKf0iI8nWGKGpMZedsY3BI/K9tZ FaT0XJx+NiCqqDz3AeNE+18W0xRqaDSC4f54yDnoSlRN7u2JfxZOAZhk5vlTjj7rvU6M M5ukpvsSR4mVunYYYfHeQWJM9B+l1J8cLCbYODEq6s0LBgnn53sw63/eAv/BCui8gZE+ b+cvRn+xq89IofvVwdb6XzFaw/p2zLOfpVp5V6jor3ODmT7uJLB/qe+mhv7J9Xju0a6d FlfxpiiX3atbdETdPsXPmsTITEH/CgeMvEjENJURULEnVb3nKhuUxUmBJrrjTPYnXxAd OyWA== X-Gm-Message-State: APjAAAWjHiQQZrV3BgLDbO4ZwHUeUUozZDGtLfXOVIjuOGIzZ0wKcZKs tFxd+hpL18SJ8ET8DPSrZzj98fiy X-Google-Smtp-Source: APXvYqzWAVZlmyuWqHxZyXj8YEifCWswtLzQBYC2E3LFgzoYRPc1C+Cy1ycngdbYx41mxfr3lCVpGg== X-Received: by 2002:a2e:9ac4:: with SMTP id p4mr6487280ljj.185.1559769559414; Wed, 05 Jun 2019 14:19:19 -0700 (PDT) Received: from dnote ([5.35.65.245]) by smtp.gmail.com with ESMTPSA id h14sm4413ljj.11.2019.06.05.14.19.18 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 05 Jun 2019 14:19:18 -0700 (PDT) Date: Thu, 6 Jun 2019 00:19:16 +0300 From: Eugene Korenevsky To: kvm@vger.kernel.org Cc: Paolo Bonzini , Sean Christopherson Subject: [PATCH v4 2/2] kvm: vmx: segment limit check: use access length Message-ID: <20190605211916.GA21812@dnote> Mail-Followup-To: Eugene Korenevsky , kvm@vger.kernel.org, Paolo Bonzini , Sean Christopherson MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.12.0 (2019-05-25) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP There is an imperfection in get_vmx_mem_address(): access length is ignored when checking the limit. To fix this, pass access length as a function argument. The access length is obvious since it is used by callers after get_vmx_mem_address() call. Signed-off-by: Eugene Korenevsky --- Changes in v2 since v1: fixed logical bug (`len` argument was not used inside get_vmx_mem_address() function); fixed the subject Changes in v3 since v2: replace is_64_bit_mode() with is_long_mode() in handle_vmwrite() Changes in v4 since v3: revert previous change arch/x86/kvm/vmx/nested.c | 28 ++++++++++++++++------------ arch/x86/kvm/vmx/nested.h | 2 +- arch/x86/kvm/vmx/vmx.c | 3 ++- 3 files changed, 19 insertions(+), 14 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 1a51bff129a8..5a364a60facf 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4008,7 +4008,7 @@ void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason, * #UD or #GP. */ int get_vmx_mem_address(struct kvm_vcpu *vcpu, unsigned long exit_qualification, - u32 vmx_instruction_info, bool wr, gva_t *ret) + u32 vmx_instruction_info, bool wr, int len, gva_t *ret) { gva_t off; bool exn; @@ -4115,7 +4115,7 @@ int get_vmx_mem_address(struct kvm_vcpu *vcpu, unsigned long exit_qualification, */ if (!(s.base == 0 && s.limit == 0xffffffff && ((s.type & 8) || !(s.type & 4)))) - exn = exn || ((u64)off + sizeof(u64) - 1 > s.limit); + exn = exn || ((u64)off + len - 1 > s.limit); } if (exn) { kvm_queue_exception_e(vcpu, @@ -4134,7 +4134,8 @@ static int nested_vmx_get_vmptr(struct kvm_vcpu *vcpu, gpa_t *vmpointer) struct x86_exception e; if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION), - vmcs_read32(VMX_INSTRUCTION_INFO), false, &gva)) + vmcs_read32(VMX_INSTRUCTION_INFO), false, + sizeof(*vmpointer), &gva)) return 1; if (kvm_read_guest_virt(vcpu, gva, vmpointer, sizeof(*vmpointer), &e)) { @@ -4386,6 +4387,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu) u64 field_value; unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION); u32 vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO); + int len; gva_t gva = 0; struct vmcs12 *vmcs12; @@ -4423,12 +4425,12 @@ static int handle_vmread(struct kvm_vcpu *vcpu) kvm_register_writel(vcpu, (((vmx_instruction_info) >> 3) & 0xf), field_value); } else { + len = is_long_mode(vcpu) ? 8 : 4; if (get_vmx_mem_address(vcpu, exit_qualification, - vmx_instruction_info, true, &gva)) + vmx_instruction_info, true, len, &gva)) return 1; /* _system ok, nested_vmx_check_permission has verified cpl=0 */ - kvm_write_guest_virt_system(vcpu, gva, &field_value, - (is_long_mode(vcpu) ? 8 : 4), NULL); + kvm_write_guest_virt_system(vcpu, gva, &field_value, len, NULL); } return nested_vmx_succeed(vcpu); @@ -4438,6 +4440,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu) static int handle_vmwrite(struct kvm_vcpu *vcpu) { unsigned long field; + int len; gva_t gva; struct vcpu_vmx *vmx = to_vmx(vcpu); unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION); @@ -4463,11 +4466,11 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) field_value = kvm_register_readl(vcpu, (((vmx_instruction_info) >> 3) & 0xf)); else { + len = is_64_bit_mode(vcpu) ? 8 : 4; if (get_vmx_mem_address(vcpu, exit_qualification, - vmx_instruction_info, false, &gva)) + vmx_instruction_info, false, len, &gva)) return 1; - if (kvm_read_guest_virt(vcpu, gva, &field_value, - (is_64_bit_mode(vcpu) ? 8 : 4), &e)) { + if (kvm_read_guest_virt(vcpu, gva, &field_value, len, &e)) { kvm_inject_page_fault(vcpu, &e); return 1; } @@ -4615,7 +4618,8 @@ static int handle_vmptrst(struct kvm_vcpu *vcpu) if (unlikely(to_vmx(vcpu)->nested.hv_evmcs)) return 1; - if (get_vmx_mem_address(vcpu, exit_qual, instr_info, true, &gva)) + if (get_vmx_mem_address(vcpu, exit_qual, instr_info, + true, sizeof(gpa_t), &gva)) return 1; /* *_system ok, nested_vmx_check_permission has verified cpl=0 */ if (kvm_write_guest_virt_system(vcpu, gva, (void *)¤t_vmptr, @@ -4661,7 +4665,7 @@ static int handle_invept(struct kvm_vcpu *vcpu) * operand is read even if it isn't needed (e.g., for type==global) */ if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION), - vmx_instruction_info, false, &gva)) + vmx_instruction_info, false, sizeof(operand), &gva)) return 1; if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) { kvm_inject_page_fault(vcpu, &e); @@ -4723,7 +4727,7 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) * operand is read even if it isn't needed (e.g., for type==global) */ if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION), - vmx_instruction_info, false, &gva)) + vmx_instruction_info, false, sizeof(operand), &gva)) return 1; if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) { kvm_inject_page_fault(vcpu, &e); diff --git a/arch/x86/kvm/vmx/nested.h b/arch/x86/kvm/vmx/nested.h index e847ff1019a2..29d205bb4e4f 100644 --- a/arch/x86/kvm/vmx/nested.h +++ b/arch/x86/kvm/vmx/nested.h @@ -21,7 +21,7 @@ void nested_sync_from_vmcs12(struct kvm_vcpu *vcpu); int vmx_set_vmx_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data); int vmx_get_vmx_msr(struct nested_vmx_msrs *msrs, u32 msr_index, u64 *pdata); int get_vmx_mem_address(struct kvm_vcpu *vcpu, unsigned long exit_qualification, - u32 vmx_instruction_info, bool wr, gva_t *ret); + u32 vmx_instruction_info, bool wr, int len, gva_t *ret); static inline struct vmcs12 *get_vmcs12(struct kvm_vcpu *vcpu) { diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 1ac167614032..6ecf9e4de2f9 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5342,7 +5342,8 @@ static int handle_invpcid(struct kvm_vcpu *vcpu) * is read even if it isn't needed (e.g., for type==all) */ if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION), - vmx_instruction_info, false, &gva)) + vmx_instruction_info, false, + sizeof(operand), &gva)) return 1; if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) {