From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754734AbdBEUXr (ORCPT + 2 others); Sun, 5 Feb 2017 15:23:47 -0500 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:27601 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753029AbdBETXR (ORCPT ); Sun, 5 Feb 2017 14:23:17 -0500 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Jim Lin , Mathias Nyman , Willy Tarreau Subject: [PATCH 3.10 109/319] usb: xhci: Fix panic if disconnect Date: Sun, 5 Feb 2017 20:18:51 +0100 Message-Id: <1486322541-8206-10-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1486322541-8206-1-git-send-email-w@1wt.eu> References: <1486322541-8206-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: From: Jim Lin commit 88716a93766b8f095cdef37a8e8f2c93aa233b21 upstream. After a device is disconnected, xhci_stop_device() will be invoked in xhci_bus_suspend(). Also the "disconnect" IRQ will have ISR to invoke xhci_free_virt_device() in this sequence. xhci_irq -> xhci_handle_event -> handle_cmd_completion -> xhci_handle_cmd_disable_slot -> xhci_free_virt_device If xhci->devs[slot_id] has been assigned to NULL in xhci_free_virt_device(), then virt_dev->eps[i].ring in xhci_stop_device() may point to an invlid address to cause kernel panic. virt_dev = xhci->devs[slot_id]; : if (virt_dev->eps[i].ring && virt_dev->eps[i].ring->dequeue) [] Unable to handle kernel paging request at virtual address 00001a68 [] pgd=ffffffc001430000 [] [00001a68] *pgd=000000013c807003, *pud=000000013c807003, *pmd=000000013c808003, *pte=0000000000000000 [] Internal error: Oops: 96000006 [#1] PREEMPT SMP [] CPU: 0 PID: 39 Comm: kworker/0:1 Tainted: G U [] Workqueue: pm pm_runtime_work [] task: ffffffc0bc0e0bc0 ti: ffffffc0bc0ec000 task.ti: ffffffc0bc0ec000 [] PC is at xhci_stop_device.constprop.11+0xb4/0x1a4 This issue is found when running with realtek ethernet device (0bda:8153). Signed-off-by: Jim Lin Signed-off-by: Mathias Nyman Signed-off-by: Willy Tarreau --- drivers/usb/host/xhci-hub.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 0f71c3a..0f6edce 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -275,6 +275,9 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend) ret = 0; virt_dev = xhci->devs[slot_id]; + if (!virt_dev) + return -ENODEV; + cmd = xhci_alloc_command(xhci, false, true, GFP_NOIO); if (!cmd) { xhci_dbg(xhci, "Couldn't allocate command structure.\n"); -- 2.8.0.rc2.1.gbe9624a