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 5F6C4C38161 for ; Tue, 5 Apr 2022 10:50:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241412AbiDEKsu (ORCPT ); Tue, 5 Apr 2022 06:48:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244532AbiDEJl1 (ORCPT ); Tue, 5 Apr 2022 05:41:27 -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 CF1CDBB932; Tue, 5 Apr 2022 02:26:36 -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 8E947B81C9D; Tue, 5 Apr 2022 09:26:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2008C385A3; Tue, 5 Apr 2022 09:26:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649150794; bh=5SKEbDrLT6+O1PlKgj+zrudt8PadU0+bYVvcmroswKE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gXRpsE1vZXnNj0WtHqoa9rXQxFEQHJHZ1I7RuPoChXoyH56tNKQx6HrRGl7EqBREx a4FeOtS3j3hzEMomPAj1a4XBaxbEaRInPJBjwXcf3HydRInrcnuNklSZ9W7DJpIR/a cYNRb5HsIZKeiNXhxB4HFLwbnIyXv4vrC/h3Gah0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Lucas De Marchi , Jani Nikula Subject: [PATCH 5.15 184/913] drm/i915/opregion: check port number bounds for SWSCI display power state Date: Tue, 5 Apr 2022 09:20:46 +0200 Message-Id: <20220405070345.370483428@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070339.801210740@linuxfoundation.org> References: <20220405070339.801210740@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: Jani Nikula commit 24a644ebbfd3b13cda702f98907f9dd123e34bf9 upstream. The mapping from enum port to whatever port numbering scheme is used by the SWSCI Display Power State Notification is odd, and the memory of it has faded. In any case, the parameter only has space for ports numbered [0..4], and UBSAN reports bit shift beyond it when the platform has port F or more. Since the SWSCI functionality is supposed to be obsolete for new platforms (i.e. ones that might have port F or more), just bail out early if the mapped and mangled port number is beyond what the Display Power State Notification can support. Fixes: 9c4b0a683193 ("drm/i915: add opregion function to notify bios of encoder enable/disable") Cc: # v3.13+ Cc: Ville Syrjälä Cc: Lucas De Marchi Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4800 Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/cc363f42d6b5a5932b6d218fefcc8bdfb15dbbe5.1644489329.git.jani.nikula@intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/display/intel_opregion.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) --- a/drivers/gpu/drm/i915/display/intel_opregion.c +++ b/drivers/gpu/drm/i915/display/intel_opregion.c @@ -376,6 +376,21 @@ int intel_opregion_notify_encoder(struct return -EINVAL; } + /* + * The port numbering and mapping here is bizarre. The now-obsolete + * swsci spec supports ports numbered [0..4]. Port E is handled as a + * special case, but port F and beyond are not. The functionality is + * supposed to be obsolete for new platforms. Just bail out if the port + * number is out of bounds after mapping. + */ + if (port > 4) { + drm_dbg_kms(&dev_priv->drm, + "[ENCODER:%d:%s] port %c (index %u) out of bounds for display power state notification\n", + intel_encoder->base.base.id, intel_encoder->base.name, + port_name(intel_encoder->port), port); + return -EINVAL; + } + if (!enable) parm |= 4 << 8;