From patchwork Mon Dec 6 14:55:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 521538 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 0FA17C433EF for ; Mon, 6 Dec 2021 15:08:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349121AbhLFPL4 (ORCPT ); Mon, 6 Dec 2021 10:11:56 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:58752 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346203AbhLFPJV (ORCPT ); Mon, 6 Dec 2021 10:09:21 -0500 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 dfw.source.kernel.org (Postfix) with ESMTPS id C3D2C61326; Mon, 6 Dec 2021 15:05:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A85FDC341C2; Mon, 6 Dec 2021 15:05:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638803152; bh=BU1QrZcFfIDx8fq7u9yoof7T7KA5DSdjqKiRzULuERU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V9VBuX/zD2t6sG+45vHlHA3kfRCCGGfvGLT+eNMkEE+bMV97Hqa5o75sk/txziGTu PVx77UoOb51xg4Bs500ODwopiZWqudVIRjSq+AYlQbTnu5cxcN7SnWjypprPN3WEXd 8z3GQSWsnzSwxxd0O8LJrNFmgwPxq8jzUdS+uaCI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marek Szyprowski , Hans de Goede , Mathias Nyman Subject: [PATCH 4.14 004/106] usb: hub: Fix locking issues with address0_mutex Date: Mon, 6 Dec 2021 15:55:12 +0100 Message-Id: <20211206145555.545111529@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211206145555.386095297@linuxfoundation.org> References: <20211206145555.386095297@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mathias Nyman commit 6cca13de26eea6d32a98d96d916a048d16a12822 upstream. Fix the circular lock dependency and unbalanced unlock of addess0_mutex introduced when fixing an address0_mutex enumeration retry race in commit ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0 race") Make sure locking order between port_dev->status_lock and address0_mutex is correct, and that address0_mutex is not unlocked in hub_port_connect "done:" codepath which may be reached without locking address0_mutex Fixes: 6ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0 race") Cc: Reported-by: Marek Szyprowski Tested-by: Hans de Goede Tested-by: Marek Szyprowski Acked-by: Hans de Goede Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20211123101656.1113518-1-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -4859,6 +4859,7 @@ static void hub_port_connect(struct usb_ struct usb_port *port_dev = hub->ports[port1 - 1]; struct usb_device *udev = port_dev->child; static int unreliable_port = -1; + bool retry_locked; /* Disconnect any existing devices under this port */ if (udev) { @@ -4915,9 +4916,10 @@ static void hub_port_connect(struct usb_ status = 0; - mutex_lock(hcd->address0_mutex); - for (i = 0; i < SET_CONFIG_TRIES; i++) { + usb_lock_port(port_dev); + mutex_lock(hcd->address0_mutex); + retry_locked = true; /* reallocate for each attempt, since references * to the previous one can escape in various ways @@ -4926,6 +4928,8 @@ static void hub_port_connect(struct usb_ if (!udev) { dev_err(&port_dev->dev, "couldn't allocate usb_device\n"); + mutex_unlock(hcd->address0_mutex); + usb_unlock_port(port_dev); goto done; } @@ -4947,13 +4951,13 @@ static void hub_port_connect(struct usb_ } /* reset (non-USB 3.0 devices) and get descriptor */ - usb_lock_port(port_dev); status = hub_port_init(hub, udev, port1, i); - usb_unlock_port(port_dev); if (status < 0) goto loop; mutex_unlock(hcd->address0_mutex); + usb_unlock_port(port_dev); + retry_locked = false; if (udev->quirks & USB_QUIRK_DELAY_INIT) msleep(2000); @@ -5043,11 +5047,14 @@ static void hub_port_connect(struct usb_ loop_disable: hub_port_disable(hub, port1, 1); - mutex_lock(hcd->address0_mutex); loop: usb_ep0_reinit(udev); release_devnum(udev); hub_free_dev(udev); + if (retry_locked) { + mutex_unlock(hcd->address0_mutex); + usb_unlock_port(port_dev); + } usb_put_dev(udev); if ((status == -ENOTCONN) || (status == -ENOTSUPP)) break; @@ -5070,8 +5077,6 @@ loop: } done: - mutex_unlock(hcd->address0_mutex); - hub_port_disable(hub, port1, 1); if (hcd->driver->relinquish_port && !hub->hdev->parent) { if (status != -ENOTCONN && status != -ENODEV)