From patchwork Mon Nov 9 12:55:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 322573 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 EC227C2D0A3 for ; Mon, 9 Nov 2020 13:44:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B91DC206B2 for ; Mon, 9 Nov 2020 13:44:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604929475; bh=ZGX1wJ93pGvHummN/+NwNi/8hSAy4jg10Vu8dky7Fes=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2F7ZGlJ6BHuwqHE+0uLj0vDhrcepeYxWH9L+FVWdlLTiIkK3rglvQe4mI5hy74bmz M6R5CP285SvA8QR0vELk7BME5ovHc6AirYo0EICNUGyc9dlcku12e6yK9gYIm+0OrA /mFbGIYKCwOrOb+jyzUrajT8ODaMwA/kE8EhCdDg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730698AbgKINof (ORCPT ); Mon, 9 Nov 2020 08:44:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:53228 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730259AbgKIM7B (ORCPT ); Mon, 9 Nov 2020 07:59:01 -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 63C1A2083B; Mon, 9 Nov 2020 12:58:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604926740; bh=ZGX1wJ93pGvHummN/+NwNi/8hSAy4jg10Vu8dky7Fes=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wnGzmAyaEwfW5Xkc+d29F2cyURZnHlcL9rboIgMtvbU/qrUiCKuf84jvvUWV5bGJy MeKoKeX+uq/xpxFma+MIPxSV+V8BbSU6G7QziVhLBJsaB457SbcLHPcxMFCwaHngVr Wt1YuPf27ws9nx/Cfugs4/JHXgchB1B/pLxG8h0E= 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 4.4 73/86] x86/kexec: Use up-to-dated screen_info copy to fill boot params Date: Mon, 9 Nov 2020 13:55:20 +0100 Message-Id: <20201109125024.292921822@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201109125020.852643676@linuxfoundation.org> References: <20201109125020.852643676@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 0bf17576dd2af..299e7fb55f16e 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -212,8 +212,7 @@ 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;