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 245EAEE3F09 for ; Mon, 11 Sep 2023 20:50:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233761AbjIKUuo (ORCPT ); Mon, 11 Sep 2023 16:50:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241023AbjIKPAC (ORCPT ); Mon, 11 Sep 2023 11:00:02 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E50F01B9 for ; Mon, 11 Sep 2023 07:59:57 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A1A6C433C7; Mon, 11 Sep 2023 14:59:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1694444397; bh=M0IzKqGfp+HghHYJQ997TxJCRNkiAi5a9urHKdJI6/c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bjoWrMQeHMjMS4Zp+rSxiCZprxna2B0BSTHFlJsn+BXirC3Aqi7Bbe+dkXos0Qm6E shqwE5ek8uebPyi/q6One0/gVHpl3/79L8ovxo4wfInvopT9T07ekvt2kkJmihluLw 3qGGfHxH9swyjxRAotJ9eR4ST8bc6nNONgtiD7gU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, RD Babiera , Heikki Krogerus , Guenter Roeck Subject: [PATCH 6.4 716/737] usb: typec: bus: verify partner exists in typec_altmode_attention Date: Mon, 11 Sep 2023 15:49:35 +0200 Message-ID: <20230911134710.517766909@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230911134650.286315610@linuxfoundation.org> References: <20230911134650.286315610@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: RD Babiera commit f23643306430f86e2f413ee2b986e0773e79da31 upstream. Some usb hubs will negotiate DisplayPort Alt mode with the device but will then negotiate a data role swap after entering the alt mode. The data role swap causes the device to unregister all alt modes, however the usb hub will still send Attention messages even after failing to reregister the Alt Mode. type_altmode_attention currently does not verify whether or not a device's altmode partner exists, which results in a NULL pointer error when dereferencing the typec_altmode and typec_altmode_ops belonging to the altmode partner. Verify the presence of a device's altmode partner before sending the Attention message to the Alt Mode driver. Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes") Cc: stable@vger.kernel.org Signed-off-by: RD Babiera Reviewed-by: Heikki Krogerus Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20230814180559.923475-1-rdbabiera@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/bus.c | 12 ++++++++++-- drivers/usb/typec/tcpm/tcpm.c | 3 ++- include/linux/usb/typec_altmode.h | 2 +- 3 files changed, 13 insertions(+), 4 deletions(-) --- a/drivers/usb/typec/bus.c +++ b/drivers/usb/typec/bus.c @@ -183,12 +183,20 @@ EXPORT_SYMBOL_GPL(typec_altmode_exit); * * Notifies the partner of @adev about Attention command. */ -void typec_altmode_attention(struct typec_altmode *adev, u32 vdo) +int typec_altmode_attention(struct typec_altmode *adev, u32 vdo) { - struct typec_altmode *pdev = &to_altmode(adev)->partner->adev; + struct altmode *partner = to_altmode(adev)->partner; + struct typec_altmode *pdev; + + if (!partner) + return -ENODEV; + + pdev = &partner->adev; if (pdev->ops && pdev->ops->attention) pdev->ops->attention(pdev, vdo); + + return 0; } EXPORT_SYMBOL_GPL(typec_altmode_attention); --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -1877,7 +1877,8 @@ static void tcpm_handle_vdm_request(stru } break; case ADEV_ATTENTION: - typec_altmode_attention(adev, p[1]); + if (typec_altmode_attention(adev, p[1])) + tcpm_log(port, "typec_altmode_attention no port partner altmode"); break; } } --- a/include/linux/usb/typec_altmode.h +++ b/include/linux/usb/typec_altmode.h @@ -67,7 +67,7 @@ struct typec_altmode_ops { int typec_altmode_enter(struct typec_altmode *altmode, u32 *vdo); int typec_altmode_exit(struct typec_altmode *altmode); -void typec_altmode_attention(struct typec_altmode *altmode, u32 vdo); +int typec_altmode_attention(struct typec_altmode *altmode, u32 vdo); int typec_altmode_vdm(struct typec_altmode *altmode, const u32 header, const u32 *vdo, int count); int typec_altmode_notify(struct typec_altmode *altmode, unsigned long conf,