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 F2963ECAAD8 for ; Fri, 23 Sep 2022 12:31:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232031AbiIWMbV (ORCPT ); Fri, 23 Sep 2022 08:31:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231670AbiIWMaw (ORCPT ); Fri, 23 Sep 2022 08:30:52 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7EC47139F47 for ; Fri, 23 Sep 2022 05:28:42 -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 ams.source.kernel.org (Postfix) with ESMTPS id E0661B82DF4 for ; Fri, 23 Sep 2022 12:28:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C4DEC433D7; Fri, 23 Sep 2022 12:28:39 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="libcu3Rl" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1663936117; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=zSq4SOzJNqbi4MDYH6SNjZYv9uMDpNSoVaymUl1nOfg=; b=libcu3RldYb5QBIWZCuGukOV+DW3+7tu9JU7z9Sklrm/FPk+55Hd/kFXNQEK38Eokk6IC3 1pRcnV8WnflcMh8B8QYTdqXP8JZTdkBO9tYMF2RVfRpYzz/JMdWuhFG++biFc2GBHr85ja U/mBkmUDO9lN08s2QADGF8NYn2AsmHQ= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 28a4fe44 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Fri, 23 Sep 2022 12:28:37 +0000 (UTC) From: "Jason A. Donenfeld" To: Geert Uytterhoeven , linux-m68k@lists.linux-m68k.org, linux-kernel@vger.kernel.org Cc: "Jason A. Donenfeld" Subject: [PATCH v2 1/2] m68k: process bootinfo records before saving them Date: Fri, 23 Sep 2022 14:28:29 +0200 Message-Id: <20220923122830.3941367-1-Jason@zx2c4.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The RNG seed boot record is memzeroed after processing, in order to preserve forward secrecy. By saving the bootinfo for procfs prior to that, forward secrecy is violated, since it becomes possible to recover past states. So, save the bootinfo block only after first processing them. Fixes: a1ee38ab1a75 ("m68k: virt: Use RNG seed from bootinfo block") Signed-off-by: Jason A. Donenfeld --- arch/m68k/kernel/setup_mm.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/m68k/kernel/setup_mm.c b/arch/m68k/kernel/setup_mm.c index e62fa8f2149b..7e7ef67cff8b 100644 --- a/arch/m68k/kernel/setup_mm.c +++ b/arch/m68k/kernel/setup_mm.c @@ -109,10 +109,9 @@ extern void paging_init(void); static void __init m68k_parse_bootinfo(const struct bi_record *record) { + const struct bi_record *first_record = record; uint16_t tag; - save_bootinfo(record); - while ((tag = be16_to_cpu(record->tag)) != BI_LAST) { int unknown = 0; const void *data = record->data; @@ -182,6 +181,8 @@ static void __init m68k_parse_bootinfo(const struct bi_record *record) record = (struct bi_record *)((unsigned long)record + size); } + save_bootinfo(first_record); + m68k_realnum_memory = m68k_num_memory; #ifdef CONFIG_SINGLE_MEMORY_CHUNK if (m68k_num_memory > 1) { -- 2.37.3