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 X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 283C4C43441 for ; Thu, 8 Nov 2018 22:19:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA81A20892 for ; Thu, 8 Nov 2018 22:19:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="0XNhIW60" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CA81A20892 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731155AbeKIH5I (ORCPT ); Fri, 9 Nov 2018 02:57:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:36360 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731902AbeKIHnw (ORCPT ); Fri, 9 Nov 2018 02:43:52 -0500 Received: from localhost (unknown [208.72.13.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B5C0B21479; Thu, 8 Nov 2018 22:06:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541714781; bh=+ld6kpdjAzEzw9IdBt4Zh1UHHCEDSgcHx+V3vvws71k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0XNhIW605St+VtNVEJp/d5nOZZSJ2oRFolXwxhZzPkGgZU+rYxtcsxhM7Tuu4bDKS gcMCcucbSjX+DhjGfxRrTg1rVmVRc4w5x+3AyJivh9l/FkRbwK7fidm1uVKaY3KC/3 dkeSkrr+wg4ngSQk26uY1q2I1WWls8ZkCEtRrtHY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jordan Glover , Mathias Nyman , Sasha Levin Subject: [PATCH 4.9 124/171] xhci: Fix USB3 NULL pointer dereference at logical disconnect. Date: Thu, 8 Nov 2018 13:51:34 -0800 Message-Id: <20181108215136.225961233@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181108215127.257643509@linuxfoundation.org> References: <20181108215127.257643509@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 2278446e2b7cd33ad894b32e7eb63afc7db6c86e ] Hub driver will try to disable a USB3 device twice at logical disconnect, racing with xhci_free_dev() callback from the first port disable. This can be triggered with "udisksctl power-off --block-device " or by writing "1" to the "remove" sysfs file for a USB3 device in 4.17-rc4. USB3 devices don't have a similar disabled link state as USB2 devices, and use a U3 suspended link state instead. In this state the port is still enabled and connected. hub_port_connect() first disconnects the device, then later it notices that device is still enabled (due to U3 states) it will try to disable the port again (set to U3). The xhci_free_dev() called during device disable is async, so checking for existing xhci->devs[i] when setting link state to U3 the second time was successful, even if device was being freed. The regression was caused by, and whole thing revealed by, Commit 44a182b9d177 ("xhci: Fix use-after-free in xhci_free_virt_device") which sets xhci->devs[i]->udev to NULL before xhci_virt_dev() returned. and causes a NULL pointer dereference the second time we try to set U3. Fix this by checking xhci->devs[i]->udev exists before setting link state. The original patch went to stable so this fix needs to be applied there as well. Fixes: 44a182b9d177 ("xhci: Fix use-after-free in xhci_free_virt_device") Cc: Reported-by: Jordan Glover Tested-by: Jordan Glover Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/host/xhci-hub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 45a03eff4db1..0f09ab5399f4 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -366,7 +366,7 @@ int xhci_find_slot_id_by_port(struct usb_hcd *hcd, struct xhci_hcd *xhci, slot_id = 0; for (i = 0; i < MAX_HC_SLOTS; i++) { - if (!xhci->devs[i]) + if (!xhci->devs[i] || !xhci->devs[i]->udev) continue; speed = xhci->devs[i]->udev->speed; if (((speed >= USB_SPEED_SUPER) == (hcd->speed >= HCD_USB3)) -- 2.17.1