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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 A1974C43460 for ; Mon, 12 Apr 2021 08:46:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8311A6124A for ; Mon, 12 Apr 2021 08:46:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237746AbhDLIqs (ORCPT ); Mon, 12 Apr 2021 04:46:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:38532 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237776AbhDLIqC (ORCPT ); Mon, 12 Apr 2021 04:46:02 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6E1B061279; Mon, 12 Apr 2021 08:45:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618217145; bh=1QToRp4t/eGel+tKZM+X5YTXzHGnEJFgybPBj1GYK+o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cCZuKhDuoKPd//lYEOCU8umeT3zwXXZZna49ZDeqTNA6VoURN92ZMfbVlyNS7RXmi gS3nnwbW1v8dxgBVURcSymn2lj4Hjk10XtkoxL1YVBu6xURqw/Ona6T4yacR+v/AEs WuKIPX4hetl8qh5PJ0Yz1TkOtgswQTeZ3N4RSVPw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Takashi Iwai , =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Rodrigo Vivi Subject: [PATCH 5.4 012/111] drm/i915: Fix invalid access to ACPI _DSM objects Date: Mon, 12 Apr 2021 10:39:50 +0200 Message-Id: <20210412084004.629496834@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412084004.200986670@linuxfoundation.org> References: <20210412084004.200986670@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: stable@vger.kernel.org From: Takashi Iwai commit b6a37a93c9ac3900987c79b726d0bb3699d8db4e upstream. intel_dsm_platform_mux_info() tries to parse the ACPI package data from _DSM for the debug information, but it assumes the fixed format without checking what values are stored in the elements actually. When an unexpected value is returned from BIOS, it may lead to GPF or NULL dereference, as reported recently. Add the checks of the contents in the returned values and skip the values for invalid cases. v1->v2: Check the info contents before dereferencing, too BugLink: http://bugzilla.opensuse.org/show_bug.cgi?id=1184074 Cc: Signed-off-by: Takashi Iwai Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20210402082317.871-1-tiwai@suse.de (cherry picked from commit 337d7a1621c7f02af867229990ac67c97da1b53a) Signed-off-by: Rodrigo Vivi Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/display/intel_acpi.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/display/intel_acpi.c +++ b/drivers/gpu/drm/i915/display/intel_acpi.c @@ -83,13 +83,31 @@ static void intel_dsm_platform_mux_info( return; } + if (!pkg->package.count) { + DRM_DEBUG_DRIVER("no connection in _DSM\n"); + return; + } + connector_count = &pkg->package.elements[0]; DRM_DEBUG_DRIVER("MUX info connectors: %lld\n", (unsigned long long)connector_count->integer.value); for (i = 1; i < pkg->package.count; i++) { union acpi_object *obj = &pkg->package.elements[i]; - union acpi_object *connector_id = &obj->package.elements[0]; - union acpi_object *info = &obj->package.elements[1]; + union acpi_object *connector_id; + union acpi_object *info; + + if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < 2) { + DRM_DEBUG_DRIVER("Invalid object for MUX #%d\n", i); + continue; + } + + connector_id = &obj->package.elements[0]; + info = &obj->package.elements[1]; + if (info->type != ACPI_TYPE_BUFFER || info->buffer.length < 4) { + DRM_DEBUG_DRIVER("Invalid info for MUX obj #%d\n", i); + continue; + } + DRM_DEBUG_DRIVER("Connector id: 0x%016llx\n", (unsigned long long)connector_id->integer.value); DRM_DEBUG_DRIVER(" port id: %s\n",