From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Guenter Roeck , Mathias Nyman , Sudip Mukherjee Subject: [PATCH 4.14 157/157] xhci: Fix use-after-free in xhci_free_virt_device Date: Sun, 1 Jul 2018 18:23:49 +0200 Message-Id: <20180701160901.122853343@linuxfoundation.org> In-Reply-To: <20180701160852.287307684@linuxfoundation.org> References: <20180701160852.287307684@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.14-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: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3551,6 +3551,7 @@ static void xhci_free_dev(struct usb_hcd del_timer_sync(&virt_dev->eps[i].stop_cmd_timer); } + virt_dev->udev = NULL; xhci_disable_slot(xhci, udev->slot_id); /* * Event command completion handler will free any data structures