From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BEEBAC0044C for ; Wed, 7 Nov 2018 17:03:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 933FA20892 for ; Wed, 7 Nov 2018 17:03:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 933FA20892 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alien8.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731548AbeKHCdx (ORCPT ); Wed, 7 Nov 2018 21:33:53 -0500 Received: from mail.skyhub.de ([5.9.137.197]:46544 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731484AbeKHCdx (ORCPT ); Wed, 7 Nov 2018 21:33:53 -0500 X-Virus-Scanned: Nedap ESD1 at mail.skyhub.de Received: from mail.skyhub.de ([127.0.0.1]) by localhost (blast.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id WFlPtErpJfNk; Wed, 7 Nov 2018 18:02:39 +0100 (CET) Received: from zn.tnic (p200300EC2BCBE000329C23FFFEA6A903.dip0.t-ipconnect.de [IPv6:2003:ec:2bcb:e000:329c:23ff:fea6:a903]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 907CF1EC0291; Wed, 7 Nov 2018 18:02:38 +0100 (CET) From: Borislav Petkov To: X86 ML Cc: "Maciej S . Szmigiero" , Tom Lendacky , LKML Subject: [PATCH 11/16] x86/microcode/AMD: Convert early parser to the new verification routines Date: Wed, 7 Nov 2018 18:02:13 +0100 Message-Id: <20181107170218.7596-12-bp@alien8.de> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181107170218.7596-1-bp@alien8.de> References: <20181107170218.7596-1-bp@alien8.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov Now that they have the required functionality, use them to verify the equivalence table and each patch, thus making parse_container() more readable. Based on a patch by "Maciej S. Szmigiero" . Signed-off-by: Borislav Petkov --- arch/x86/kernel/cpu/microcode/amd.c | 46 +++++++++++++++-------------- 1 file changed, 24 insertions(+), 22 deletions(-) diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index 79216cfb9f72..5775dc996df3 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -293,17 +293,18 @@ static ssize_t parse_container(u8 *ucode, ssize_t size, struct cont_desc *desc) u16 eq_id; u8 *buf; - /* Am I looking at an equivalence table header? */ - if (hdr[0] != UCODE_MAGIC || - hdr[1] != UCODE_EQUIV_CPU_TABLE_TYPE || - hdr[2] == 0) - return CONTAINER_HDR_SZ; + if (!verify_equivalence_table(ucode, size, true)) + return 0; buf = ucode; eq = (struct equiv_cpu_entry *)(buf + CONTAINER_HDR_SZ); - /* Find the equivalence ID of our CPU in this table: */ + /* + * Find the equivalence ID of our CPU in this table. Even if this table + * doesn't contain a patch for the CPU, scan through the whole container + * so that it can be skipped in case there are other containers appended. + */ eq_id = find_equiv_id(eq, desc->cpuid_1_eax); buf += hdr[2] + CONTAINER_HDR_SZ; @@ -316,29 +317,29 @@ static ssize_t parse_container(u8 *ucode, ssize_t size, struct cont_desc *desc) while (size > 0) { struct microcode_amd *mc; u32 patch_size; + int ret; - hdr = (u32 *)buf; - - if (hdr[0] != UCODE_UCODE_TYPE) - break; - - /* Sanity-check patch size. */ - patch_size = hdr[1]; - if (patch_size > PATCH_MAX_SIZE) - break; - - /* Skip patch section header: */ - buf += SECTION_HDR_SIZE; - size -= SECTION_HDR_SIZE; + ret = verify_patch(x86_family(desc->cpuid_1_eax), buf, size, &patch_size, true); + if (ret < 0) { + /* + * Patch verification failed, skip to the next + * container, if there's one: + */ + goto out; + } else if (ret > 0) { + goto skip; + } - mc = (struct microcode_amd *)buf; + mc = (struct microcode_amd *)(buf + SECTION_HDR_SIZE); if (eq_id == mc->hdr.processor_rev_id) { desc->psize = patch_size; desc->mc = mc; } - buf += patch_size; - size -= patch_size; +skip: + /* Skip patch section header too: */ + buf += patch_size + SECTION_HDR_SIZE; + size -= patch_size + SECTION_HDR_SIZE; } /* @@ -355,6 +356,7 @@ static ssize_t parse_container(u8 *ucode, ssize_t size, struct cont_desc *desc) return 0; } +out: return orig_size - size; } -- 2.19.1