From patchwork Fri Aug 11 18:47:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: RD Babiera X-Patchwork-Id: 713286 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 5959EC001DE for ; Fri, 11 Aug 2023 18:48:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235503AbjHKSsK (ORCPT ); Fri, 11 Aug 2023 14:48:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48126 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229577AbjHKSsJ (ORCPT ); Fri, 11 Aug 2023 14:48:09 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB24E30EA for ; Fri, 11 Aug 2023 11:48:08 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-d66af3c8ac7so1099172276.1 for ; Fri, 11 Aug 2023 11:48:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1691779688; x=1692384488; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=ZJJ8UdAIxIsw1LkzQ8Bf6m1ij6K720NrGCKMd7eniDM=; b=oZKX9eh/oR9Kkzl97al4UScWBn7jnrWuhJe5205va1AhljySM2gHSaH1yj7tV/v3T9 aS1NbtndUEeMUBFsb8BNrkCG3ADshR1Qr/8RHv8SiMeasr711vA+HCF655Bfs+fKp4Ae wKCf4xI9ILtCQqA/nd3FZXXl8+KxttPoD8W9TFJM9CQXz6niVgstQCNTBANbR2MPKK7N gba7m0SMNqO8IeUG+y7voRqfyMF9IMss5oeEk7ziuFi6rM99EvX/tz4EOaCjJdKMqxof 3ZmDfA0WaWkSxuU7cGN9n8rPaq3NrupxQwx8VG3MNnq3PBzvFyvI3FlR+75ocnGUDTP+ QCyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691779688; x=1692384488; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=ZJJ8UdAIxIsw1LkzQ8Bf6m1ij6K720NrGCKMd7eniDM=; b=K00O4Imk23ygDjoB4JhhmOtWTejdLHyAnZNugnBvVqY2/LL3/d7jh9qG934LGJE7Pc JxiSWd0u7k6eoDQSdwunNPFVyvy4vd6NDGpqEho7zym1Ye/SwY/Bgx5aisERACEILv30 GsCHW/7BM4iNWLGL7oDSNr7l5X750xi7I2MS6rX4QevCKbpimsnkPISXdkaMAdgOprvd s3zxeb8PVq6YJsmXigDpU+4t8/pJwJFTBEMHKUIvcDZvx3RfVao9PHhMvP9Pvrscb8ia v38e2VaeAq2JG6hgNVQ/p2XkiyF5lH13AgPogJWQnEJvgGk8GXLxmBGMTKRJ43KgwUu7 ourA== X-Gm-Message-State: AOJu0Yw3I7AUkNWbbPV87S8UVvargHj7YZXVS0YkvCB5+WXqtVjQIef4 4D1s3m/alnOZVjY2R7w4V8FNuCmleLWg7Vk= X-Google-Smtp-Source: AGHT+IEnRj3XgadHnPY0JsCnuxHjF2khkZv3Wyf3q91Z5QvsEE5u2YoEPQOSwguVfdhtyYW/HmP8lMT6za6KB+g= X-Received: from rdbabiera.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:18a8]) (user=rdbabiera job=sendgmr) by 2002:a25:d153:0:b0:d3f:3186:2296 with SMTP id i80-20020a25d153000000b00d3f31862296mr49820ybg.3.1691779687961; Fri, 11 Aug 2023 11:48:07 -0700 (PDT) Date: Fri, 11 Aug 2023 18:47:54 +0000 Mime-Version: 1.0 X-Mailer: git-send-email 2.41.0.640.ga95def55d0-goog Message-ID: <20230811184754.1886458-1-rdbabiera@google.com> Subject: [PATCH v2] 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. This patch verifies 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 --- 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. --- 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..b0328e922989 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 invalid port partner"); 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,