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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDCA3C4332F for ; Wed, 19 Oct 2022 09:05:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232203AbiJSJFX (ORCPT ); Wed, 19 Oct 2022 05:05:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232450AbiJSJES (ORCPT ); Wed, 19 Oct 2022 05:04:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59EE4AE224; Wed, 19 Oct 2022 01:57:37 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0DE2D6181D; Wed, 19 Oct 2022 08:53:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FF81C433C1; Wed, 19 Oct 2022 08:53:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666169616; bh=DxdqHRq9n3CnM6oqOwqOVl6LE5qMcE9fhLL5nLUgjn8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IBRPN1AjWBEZ2IfWKKrF9BaRdlaobdrjDtkVork5TcsFGEgE33PT4YhOWZSN5T7hs VJZ9LsN0O/18jCuMoMzXDGIsr7pK19dims7egdAp3Z7y4sXlQzOO7vJ9JWKnZgjhfd zCVr0HLw13V5JiOM0dLqgEYa6Hsh+DpviVVAxRUg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Micay , Kees Cook , Borislav Petkov , Sasha Levin Subject: [PATCH 6.0 310/862] x86/microcode/AMD: Track patch allocation size explicitly Date: Wed, 19 Oct 2022 10:26:37 +0200 Message-Id: <20221019083303.715483748@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221019083249.951566199@linuxfoundation.org> References: <20221019083249.951566199@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kees Cook [ Upstream commit 712f210a457d9c32414df246a72781550bc23ef6 ] In preparation for reducing the use of ksize(), record the actual allocation size for later memcpy(). This avoids copying extra (uninitialized!) bytes into the patch buffer when the requested allocation size isn't exactly the size of a kmalloc bucket. Additionally, fix potential future issues where runtime bounds checking will notice that the buffer was allocated to a smaller value than returned by ksize(). Fixes: 757885e94a22 ("x86, microcode, amd: Early microcode patch loading support for AMD") Suggested-by: Daniel Micay Signed-off-by: Kees Cook Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/lkml/CA+DvKQ+bp7Y7gmaVhacjv9uF6Ar-o4tet872h4Q8RPYPJjcJQA@mail.gmail.com/ Signed-off-by: Sasha Levin --- arch/x86/include/asm/microcode.h | 1 + arch/x86/kernel/cpu/microcode/amd.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h index 0c3d3440fe27..aa675783412f 100644 --- a/arch/x86/include/asm/microcode.h +++ b/arch/x86/include/asm/microcode.h @@ -9,6 +9,7 @@ struct ucode_patch { struct list_head plist; void *data; /* Intel uses only this one */ + unsigned int size; u32 patch_id; u16 equiv_cpu; }; diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index 8b2fcdfa6d31..615bc6efa1dd 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -788,6 +788,7 @@ static int verify_and_add_patch(u8 family, u8 *fw, unsigned int leftover, kfree(patch); return -EINVAL; } + patch->size = *patch_size; mc_hdr = (struct microcode_header_amd *)(fw + SECTION_HDR_SIZE); proc_id = mc_hdr->processor_rev_id; @@ -869,7 +870,7 @@ load_microcode_amd(bool save, u8 family, const u8 *data, size_t size) return ret; memset(amd_ucode_patch, 0, PATCH_MAX_SIZE); - memcpy(amd_ucode_patch, p->data, min_t(u32, ksize(p->data), PATCH_MAX_SIZE)); + memcpy(amd_ucode_patch, p->data, min_t(u32, p->size, PATCH_MAX_SIZE)); return ret; } -- 2.35.1