From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:50746 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729053AbeIXRlw (ORCPT ); Mon, 24 Sep 2018 13:41:52 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Guenter Roeck , Mathias Nyman , Matthias Kaehlcke Subject: [PATCH 3.18 059/105] xhci: Fix use-after-free in xhci_free_virt_device Date: Mon, 24 Sep 2018 13:33:45 +0200 Message-Id: <20180924113119.491292892@linuxfoundation.org> In-Reply-To: <20180924113113.268650190@linuxfoundation.org> References: <20180924113113.268650190@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Nyman commit 44a182b9d17765514fa2b1cc911e4e65134eef93 upstream. KASAN found a use-after-free in xhci_free_virt_device+0x33b/0x38e where xhci_free_virt_device() sets slot id to 0 if udev exists: if (dev->udev && dev->udev->slot_id) dev->udev->slot_id = 0; dev->udev will be true even if udev is freed because dev->udev is not set to NULL. set dev->udev pointer to NULL in xhci_free_dev() The original patch went to stable so this fix needs to be applied there as well. Fixes: a400efe455f7 ("xhci: zero usb device slot_id member when disabling and freeing a xhci slot") Cc: Reported-by: Guenter Roeck Reviewed-by: Guenter Roeck Tested-by: Guenter Roeck Signed-off-by: Mathias Nyman Signed-off-by: Matthias Kaehlcke Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3630,6 +3630,9 @@ void xhci_free_dev(struct usb_hcd *hcd, } spin_lock_irqsave(&xhci->lock, flags); + + virt_dev->udev = NULL; + /* Don't disable the slot if the host controller is dead. */ state = readl(&xhci->op_regs->status); if (state == 0xffffffff || (xhci->xhc_state & XHCI_STATE_DYING) ||