From patchwork Wed Mar 8 15:42:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 661587 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 341BAC64EC4 for ; Wed, 8 Mar 2023 15:45:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232198AbjCHPpm (ORCPT ); Wed, 8 Mar 2023 10:45:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232300AbjCHPpA (ORCPT ); Wed, 8 Mar 2023 10:45:00 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9EA225E05 for ; Wed, 8 Mar 2023 07:43:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1678290180; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TSWG9DFcmaHYhC7dIu4qV+c+MWuYP7IP2kkl0lMkChA=; b=PkfG9jeqJXvrDSEyPxRWLqhk/A1Ov/QT2HxA2UlTOD7OVyIzVhZcRWD8wcGTeb9E4A6Eo3 GQmPpCUNsH4Tif4FBoxZyijOb6R0y3g0xbDA4NuLoD99E/5UfDTlsoKvxNt6Kl32YglquL ulFZgrePoOWqBJLAl69t/tzEWz2GwpA= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-613-plEZV9wLP3iyWqQyYZpgdA-1; Wed, 08 Mar 2023 10:42:56 -0500 X-MC-Unique: plEZV9wLP3iyWqQyYZpgdA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A0305802D38; Wed, 8 Mar 2023 15:42:55 +0000 (UTC) Received: from localhost.localdomain (unknown [10.39.195.179]) by smtp.corp.redhat.com (Postfix) with ESMTP id C1324492B04; Wed, 8 Mar 2023 15:42:54 +0000 (UTC) From: Hans de Goede To: Greg Kroah-Hartman , Heikki Krogerus Cc: Hans de Goede , linux-usb@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v4 2/3] usb: ucsi: Fix ucsi->connector race Date: Wed, 8 Mar 2023 16:42:43 +0100 Message-Id: <20230308154244.722337-3-hdegoede@redhat.com> In-Reply-To: <20230308154244.722337-1-hdegoede@redhat.com> References: <20230308154244.722337-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org ucsi_init() which runs from a workqueue sets ucsi->connector and on an error will clear it again. ucsi->connector gets dereferenced by ucsi_resume(), this checks for ucsi->connector being NULL in case ucsi_init() has not finished yet; or in case ucsi_init() has failed. ucsi_init() setting ucsi->connector and then clearing it again on an error creates a race where the check in ucsi_resume() may pass, only to have ucsi->connector free-ed underneath it when ucsi_init() hits an error. Fix this race by making ucsi_init() store the connector array in a local variable and only assign it to ucsi->connector on success. Fixes: bdc62f2bae8f ("usb: typec: ucsi: Simplified registration and I/O API") Cc: stable@vger.kernel.org Reviewed-by: Heikki Krogerus Signed-off-by: Hans de Goede --- Changes in v4: - Rebase on top of v6.3-rc1 Changes in v3: - Assign connector[i].index before calling ucsi_register_port() instead of passing i to ucsi_register_port() --- drivers/usb/typec/ucsi/ucsi.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 0623861c597b..8d1baf28df55 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -1125,12 +1125,11 @@ static struct fwnode_handle *ucsi_find_fwnode(struct ucsi_connector *con) return NULL; } -static int ucsi_register_port(struct ucsi *ucsi, int index) +static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con) { struct usb_power_delivery_desc desc = { ucsi->cap.pd_version}; struct usb_power_delivery_capabilities_desc pd_caps; struct usb_power_delivery_capabilities *pd_cap; - struct ucsi_connector *con = &ucsi->connector[index]; struct typec_capability *cap = &con->typec_cap; enum typec_accessory *accessory = cap->accessory; enum usb_role u_role = USB_ROLE_NONE; @@ -1151,7 +1150,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) init_completion(&con->complete); mutex_init(&con->lock); INIT_LIST_HEAD(&con->partner_tasks); - con->num = index + 1; con->ucsi = ucsi; cap->fwnode = ucsi_find_fwnode(con); @@ -1328,7 +1326,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) */ static int ucsi_init(struct ucsi *ucsi) { - struct ucsi_connector *con; + struct ucsi_connector *con, *connector; u64 command, ntfy; int ret; int i; @@ -1359,16 +1357,16 @@ static int ucsi_init(struct ucsi *ucsi) } /* Allocate the connectors. Released in ucsi_unregister() */ - ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1, - sizeof(*ucsi->connector), GFP_KERNEL); - if (!ucsi->connector) { + connector = kcalloc(ucsi->cap.num_connectors + 1, sizeof(*connector), GFP_KERNEL); + if (!connector) { ret = -ENOMEM; goto err_reset; } /* Register all connectors */ for (i = 0; i < ucsi->cap.num_connectors; i++) { - ret = ucsi_register_port(ucsi, i); + connector[i].num = i + 1; + ret = ucsi_register_port(ucsi, &connector[i]); if (ret) goto err_unregister; } @@ -1380,11 +1378,12 @@ static int ucsi_init(struct ucsi *ucsi) if (ret < 0) goto err_unregister; + ucsi->connector = connector; ucsi->ntfy = ntfy; return 0; err_unregister: - for (con = ucsi->connector; con->port; con++) { + for (con = connector; con->port; con++) { ucsi_unregister_partner(con); ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON); ucsi_unregister_port_psy(con); @@ -1400,10 +1399,7 @@ static int ucsi_init(struct ucsi *ucsi) typec_unregister_port(con->port); con->port = NULL; } - - kfree(ucsi->connector); - ucsi->connector = NULL; - + kfree(connector); err_reset: memset(&ucsi->cap, 0, sizeof(ucsi->cap)); ucsi_reset_ppm(ucsi);