From patchwork Fri Aug 11 21:37:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: RD Babiera X-Patchwork-Id: 713171 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 73A13C001B0 for ; Fri, 11 Aug 2023 21:37:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236972AbjHKVhz (ORCPT ); Fri, 11 Aug 2023 17:37:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47808 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236965AbjHKVhw (ORCPT ); Fri, 11 Aug 2023 17:37:52 -0400 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7AF2F30C8 for ; Fri, 11 Aug 2023 14:37:40 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-584139b6b03so27963677b3.3 for ; Fri, 11 Aug 2023 14:37:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1691789859; x=1692394659; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=bMZsVZSnTwxLBUZ0gFEh6Z7YIIkBHuiAxRukuullP64=; b=72OZU8nCPwmXMWau/bDePSdndzSri29uvu09IJBTIwz9ICBVapeWg+SDFxS7gpRIBd +zoymg8oFyxYMMo4M9G0obTzeT639Wm5c+nZxA2PPVoPx6nSJ7X5SeuHxeU+U+RlN9U1 hjbl+ZBBf4O19aItCQ1LkQTdOQR8LZoFzMJwgXYMgGdLoymniI0bFQUGGlBoH+WYmuHb uP7n+nRe8wFb8HC7UzjnjPJiAaRlFzCvpVufqlCtPkzJvmGntJ6WVu3PaNLJIwAlmwyg HcwoXb2r6JaBHuENjKDKAu+9OBarskuwun5cAk4THv3SdbEQ6o/arCQw+XEJtDCebTqC LXRA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691789859; x=1692394659; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=bMZsVZSnTwxLBUZ0gFEh6Z7YIIkBHuiAxRukuullP64=; b=ATWu5dl5oCqGSwj86PYRTvh6aPDr8pvTR0fwl4AWKjo+zP/oxDRvmrY85EKtH/1I2r lC8Et3P0b3W6gtcDb6luv6RFVdyezvm7PIZ014ixNZ9YiOT9pf2+upwho+Fciky2qEAX 36ZF8P2pkGMOeyeXszDxQIAFNie+ULhMqoI3+JLZa8N8onXyM+Nla0YTFJSLqt7hJJQs fir2GetlN/IWvowErB9/jyLXefeWgHAUoQjN/BRkq9KNCw1RtT9PgPG2y/xmIrRGz7qC IVHKiO+RCnlM9sdqeNRS8Hf3K3zke+BoTLR/FyIP+a4GZ8F1hasemVEcvzL97aG1Mvq6 7AYw== X-Gm-Message-State: AOJu0Yy8+ri8BThtuokiC5gQ2YydsF9SB7PvcN/cNC/1IGRrdlMLC7HW BJ6LVw6Bf2NIRbjaUpAzDsqBdYrctLs4eM0= X-Google-Smtp-Source: AGHT+IFP1TLkOnN0mXKWfJp/bqh9cjlj0kJRsKyzdyvggLP4N2xzIVCKSkVK86ZkSomHRWVcdvm5Y14/oZ6JJ58= X-Received: from rdbabiera.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:18a8]) (user=rdbabiera job=sendgmr) by 2002:a81:ae12:0:b0:584:41b7:30e7 with SMTP id m18-20020a81ae12000000b0058441b730e7mr52742ywh.0.1691789859770; Fri, 11 Aug 2023 14:37:39 -0700 (PDT) Date: Fri, 11 Aug 2023 21:37:32 +0000 Mime-Version: 1.0 X-Mailer: git-send-email 2.41.0.640.ga95def55d0-goog Message-ID: <20230811213732.3325896-1-rdbabiera@google.com> Subject: [PATCH v3] usb: typec: bus: verify partner exists in typec_altmode_attention From: RD Babiera To: heikki.krogerus@linux.intel.com, gregkh@linuxfoundation.org, linux@roeck-us.net Cc: badhri@google.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, RD Babiera , stable@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org 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: Guenter Roeck --- Changes since v1: * Only assigns pdev if altmode partner exists in typec_altmode_attention * Removed error return in typec_altmode_attention if Alt Mode does not implement Attention messages. * Changed tcpm_log message to indicate that altmode partner does not exist, as it only logs in that case. --- Changes since v2: * Changed tcpm_log message to accurately reflect error * Revised commit message --- drivers/usb/typec/bus.c | 12 ++++++++++-- drivers/usb/typec/tcpm/tcpm.c | 5 ++++- include/linux/usb/typec_altmode.h | 2 +- 3 files changed, 15 insertions(+), 4 deletions(-) base-commit: f176638af476c6d46257cc3303f5c7cf47d5967d diff --git a/drivers/usb/typec/bus.c b/drivers/usb/typec/bus.c index fe5b9a2e61f5..e95ec7e382bb 100644 --- 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); diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 5a7d8cc04628..97b7b22e9cf1 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -1791,6 +1791,7 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port, u32 p[PD_MAX_PAYLOAD]; u32 response[8] = { }; int i, rlen = 0; + int ret; for (i = 0; i < cnt; i++) p[i] = le32_to_cpu(payload[i]); @@ -1877,7 +1878,9 @@ static void tcpm_handle_vdm_request(struct tcpm_port *port, } break; case ADEV_ATTENTION: - typec_altmode_attention(adev, p[1]); + ret = typec_altmode_attention(adev, p[1]); + if (ret) + tcpm_log(port, "typec_altmode_attention NULL port partner altmode"); break; } } diff --git a/include/linux/usb/typec_altmode.h b/include/linux/usb/typec_altmode.h index 350d49012659..28aeef8f9e7b 100644 --- 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,