From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757429Ab1FPPcg (ORCPT ); Thu, 16 Jun 2011 11:32:36 -0400 Received: from s15228384.onlinehome-server.info ([87.106.30.177]:45693 "EHLO mail.x86-64.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756968Ab1FPPce (ORCPT ); Thu, 16 Jun 2011 11:32:34 -0400 From: Borislav Petkov To: Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner Cc: Ben Hutchings , LKML , Borislav Petkov Subject: [PATCH 2/2] x86, microcode, AMD: Fix section header size check Date: Thu, 16 Jun 2011 17:32:07 +0200 Message-Id: <1308238327-27965-3-git-send-email-bp@amd64.org> X-Mailer: git-send-email 1.7.4.rc2 In-Reply-To: <1308238327-27965-1-git-send-email-bp@amd64.org> References: <1308238327-27965-1-git-send-email-bp@amd64.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov The ucode size check has to take the section header size into account too when sanity checking the section length. Shorten and clarify define names, while at it. Caught-by: Ben Hutchings Link: http://lkml.kernel.org/r/1302752223.5282.674.camel@localhost Signed-off-by: Borislav Petkov --- arch/x86/kernel/microcode_amd.c | 15 ++++++++------- 1 files changed, 8 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c index d30d67c..591be0e 100644 --- a/arch/x86/kernel/microcode_amd.c +++ b/arch/x86/kernel/microcode_amd.c @@ -66,8 +66,8 @@ struct microcode_amd { unsigned int mpb[0]; }; -#define UCODE_CONTAINER_SECTION_HDR 8 -#define UCODE_CONTAINER_HEADER_SIZE 12 +#define SECTION_HDR_SIZE 8 +#define CONTAINER_HDR_SZ 12 static struct equiv_cpu_entry *equiv_cpu_table; @@ -177,7 +177,7 @@ static unsigned int verify_ucode_size(int cpu, const u8 *buf, unsigned int size) actual_size = *(u32 *)(buf + 4); - if (actual_size > size || actual_size > max_size) { + if (actual_size + SECTION_HDR_SIZE > size || actual_size > max_size) { pr_err("section size mismatch\n"); return 0; } @@ -204,8 +204,8 @@ get_next_ucode(int cpu, const u8 *buf, unsigned int size, unsigned int *mc_size) if (!mc) goto out; - get_ucode_data(mc, buf + UCODE_CONTAINER_SECTION_HDR, actual_size); - *mc_size = actual_size + UCODE_CONTAINER_SECTION_HDR; + get_ucode_data(mc, buf + SECTION_HDR_SIZE, actual_size); + *mc_size = actual_size + SECTION_HDR_SIZE; out: return mc; @@ -229,9 +229,10 @@ static int install_equiv_cpu_table(const u8 *buf) return -ENOMEM; } - get_ucode_data(equiv_cpu_table, buf + UCODE_CONTAINER_HEADER_SIZE, size); + get_ucode_data(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size); - return size + UCODE_CONTAINER_HEADER_SIZE; /* add header length */ + /* add header length */ + return size + CONTAINER_HDR_SZ; } static void free_equiv_cpu_table(void) -- 1.7.4.rc2