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=-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=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 5DD38C388F7 for ; Mon, 9 Nov 2020 13:32:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 14F6C2067B for ; Mon, 9 Nov 2020 13:32:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604928741; bh=AzkNGzZcPAS3X/Z8RvdqSqjKNkUC0T4JNxfRrlDIuhY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bvH1Olpw1dfMeZpUWdkyJt54UCaJhrApp9+UIrcbRS3awGyi+Qbx9tH0nBvNEkQrM 0XNwvdCYGyZ/kzloQWCUM1P3x4aDzc/6Odsdhi9/50LkCwCTGFm1irdpExScxjVVcu Oo2mrFHhqOCn1e/xcrIjiRZGQxRJAL0LQ+cErf0g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732718AbgKINcT (ORCPT ); Mon, 9 Nov 2020 08:32:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:60760 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731408AbgKINHu (ORCPT ); Mon, 9 Nov 2020 08:07:50 -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 B2FF520731; Mon, 9 Nov 2020 13:07:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604927270; bh=AzkNGzZcPAS3X/Z8RvdqSqjKNkUC0T4JNxfRrlDIuhY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=biyQDnn3uJAPLu3wRKffy/21d123DAqKE6qzp+jUeDXesM3eHLuR43r0CIyrPLmrZ hZd3FZMRb8r1qllAssjqmF4TjPLtdO0+VwVv9eRbAbyiuo7r10KAInHq75vXaUegMJ 0WCDY3lCcF0ScZGv8Pa8Vyfm7ZNyINiGG5t89sKw= 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 4.14 27/48] x86/kexec: Use up-to-dated screen_info copy to fill boot params Date: Mon, 9 Nov 2020 13:55:36 +0100 Message-Id: <20201109125018.096460512@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201109125016.734107741@linuxfoundation.org> References: <20201109125016.734107741@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 4d948d87f01cc..a65636d60296c 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -211,8 +211,7 @@ 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; -- 2.27.0