4.16-stable review patch. If anyone has any objections, please let me know.
------------------ From: Mathias Nyman <[email protected]> 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: <[email protected]> Reported-by: Guenter Roeck <[email protected]> Reviewed-by: Guenter Roeck <[email protected]> Tested-by: Guenter Roeck <[email protected]> Signed-off-by: Mathias Nyman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/usb/host/xhci.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3548,6 +3548,7 @@ static void xhci_free_dev(struct usb_hcd del_timer_sync(&virt_dev->eps[i].stop_cmd_timer); } xhci_debugfs_remove_slot(xhci, udev->slot_id); + virt_dev->udev = NULL; ret = xhci_disable_slot(xhci, udev->slot_id); if (ret) xhci_free_virt_device(xhci, udev->slot_id);
