From patchwork Mon Nov 9 12:55:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 322756 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 681D3C4741F for ; Mon, 9 Nov 2020 13:13:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1AE2820867 for ; Mon, 9 Nov 2020 13:13:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604927605; bh=3IT1W8GWAaPGvllvqJgTf/2L6BSmURozVhV6akR//ds=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DipU7yDr33BO42W+E/63m2CZoi3EgI/xIvmEd6nLJmZLxLKdQvKUWE9LeUTFy9znE Z3Ljql+tWPwZttYrJ9n2MaQnAeSnHYnClJdLSkvxsKUqvECGG+1sNO61t2izh8F4ti itjo7Iek5k574bkWe1TfrvOfmimD3ATxrLeVHBIs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731783AbgKINNX (ORCPT ); Mon, 9 Nov 2020 08:13:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:39180 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732944AbgKINNV (ORCPT ); Mon, 9 Nov 2020 08:13:21 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2DFC32076E; Mon, 9 Nov 2020 13:13:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604927600; bh=3IT1W8GWAaPGvllvqJgTf/2L6BSmURozVhV6akR//ds=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MZGnih6UFToHd21jfdWgCkzVL1JiJ8WGqfdayLDH2eO4Mr0fICrte20VSeHS760R+ ARado3P1l5Y+OvvbZUGDQIgAuzuELO0y+rzS9jkgJj2riUIeZLL1qc0Co02sLqiAJf 2aHcMsNgWKEZZElOo0LSHH4zRNdIlpSIy70kJey8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kairui Song , Ingo Molnar , Sasha Levin Subject: [PATCH 5.4 44/85] x86/kexec: Use up-to-dated screen_info copy to fill boot params Date: Mon, 9 Nov 2020 13:55:41 +0100 Message-Id: <20201109125024.709088959@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201109125022.614792961@linuxfoundation.org> References: <20201109125022.614792961@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kairui Song [ Upstream commit afc18069a2cb7ead5f86623a5f3d4ad6e21f940d ] kexec_file_load() currently reuses the old boot_params.screen_info, but if drivers have change the hardware state, boot_param.screen_info could contain invalid info. For example, the video type might be no longer VGA, or the frame buffer address might be changed. If the kexec kernel keeps using the old screen_info, kexec'ed kernel may attempt to write to an invalid framebuffer memory region. There are two screen_info instances globally available, boot_params.screen_info and screen_info. Later one is a copy, and is updated by drivers. So let kexec_file_load use the updated copy. [ mingo: Tidied up the changelog. ] Signed-off-by: Kairui Song Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20201014092429.1415040-2-kasong@redhat.com Signed-off-by: Sasha Levin --- arch/x86/kernel/kexec-bzimage64.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index d2f4e706a428c..b8b3b84308edc 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -210,8 +210,7 @@ setup_boot_parameters(struct kimage *image, struct boot_params *params, params->hdr.hardware_subarch = boot_params.hdr.hardware_subarch; /* Copying screen_info will do? */ - memcpy(¶ms->screen_info, &boot_params.screen_info, - sizeof(struct screen_info)); + memcpy(¶ms->screen_info, &screen_info, sizeof(struct screen_info)); /* Fill in memsize later */ params->screen_info.ext_mem_k = 0;