#include <linux/export.h>
#include "wusbhc.h"
-static void wusbhc_set_gtk_callback(struct urb *urb);
-static void wusbhc_gtk_rekey_done_work(struct work_struct *work);
+static void wusbhc_gtk_rekey_work(struct work_struct *work);
int wusbhc_sec_create(struct wusbhc *wusbhc)
{
wusbhc->gtk.descr.bLength = sizeof(wusbhc->gtk.descr) + sizeof(wusbhc->gtk.data);
wusbhc->gtk.descr.bDescriptorType = USB_DT_KEY;
wusbhc->gtk.descr.bReserved = 0;
+ wusbhc->gtk_index = 0;
- wusbhc->gtk_index = wusb_key_index(0, WUSB_KEY_INDEX_TYPE_GTK,
- WUSB_KEY_INDEX_ORIGINATOR_HOST);
-
- INIT_WORK(&wusbhc->gtk_rekey_done_work, wusbhc_gtk_rekey_done_work);
+ INIT_WORK(&wusbhc->gtk_rekey_work, wusbhc_gtk_rekey_work);
return 0;
}
wusbhc_generate_gtk(wusbhc);
result = wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
- &wusbhc->gtk.descr.bKeyData, key_size);
+ &wusbhc->gtk.descr.bKeyData, key_size);
if (result < 0)
dev_err(wusbhc->dev, "cannot set GTK for the host: %d\n",
result);
*/
void wusbhc_sec_stop(struct wusbhc *wusbhc)
{
- cancel_work_sync(&wusbhc->gtk_rekey_done_work);
+ cancel_work_sync(&wusbhc->gtk_rekey_work);
}
static int wusb_dev_set_gtk(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
{
struct usb_device *usb_dev = wusb_dev->usb_dev;
+ u8 key_index = wusb_key_index(wusbhc->gtk_index,
+ WUSB_KEY_INDEX_TYPE_GTK, WUSB_KEY_INDEX_ORIGINATOR_HOST);
return usb_control_msg(
usb_dev, usb_sndctrlpipe(usb_dev, 0),
USB_REQ_SET_DESCRIPTOR,
USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
- USB_DT_KEY << 8 | wusbhc->gtk_index, 0,
+ USB_DT_KEY << 8 | key_index, 0,
&wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
1000);
}
* Once all connected and authenticated devices have received the new
* GTK, switch the host to using it.
*/
-static void wusbhc_gtk_rekey_done_work(struct work_struct *work)
+static void wusbhc_gtk_rekey_work(struct work_struct *work)
{
- struct wusbhc *wusbhc = container_of(work, struct wusbhc, gtk_rekey_done_work);
+ struct wusbhc *wusbhc = container_of(work,
+ struct wusbhc, gtk_rekey_work);
size_t key_size = sizeof(wusbhc->gtk.data);
+ int port_idx;
+ struct wusb_dev *wusb_dev, *wusb_dev_next;
+ LIST_HEAD(rekey_list);
mutex_lock(&wusbhc->mutex);
+ /* generate the new key */
+ wusbhc_generate_gtk(wusbhc);
+ /* roll the gtk index. */
+ wusbhc->gtk_index = (wusbhc->gtk_index + 1) % (WUSB_KEY_INDEX_MAX + 1);
+ /*
+ * Save all connected devices on a list while holding wusbhc->mutex and
+ * take a reference to each one. Then submit the set key request to
+ * them after releasing the lock in order to avoid a deadlock.
+ */
+ for (port_idx = 0; port_idx < wusbhc->ports_max; port_idx++) {
+ wusb_dev = wusbhc->port[port_idx].wusb_dev;
+ if (!wusb_dev || !wusb_dev->usb_dev
+ || !wusb_dev->usb_dev->authenticated)
+ continue;
- if (--wusbhc->pending_set_gtks == 0)
- wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
-
+ wusb_dev_get(wusb_dev);
+ list_add_tail(&wusb_dev->rekey_node, &rekey_list);
+ }
mutex_unlock(&wusbhc->mutex);
-}
-static void wusbhc_set_gtk_callback(struct urb *urb)
-{
- struct wusbhc *wusbhc = urb->context;
+ /* Submit the rekey requests without holding wusbhc->mutex. */
+ list_for_each_entry_safe(wusb_dev, wusb_dev_next, &rekey_list,
+ rekey_node) {
+ list_del_init(&wusb_dev->rekey_node);
+ dev_dbg(&wusb_dev->usb_dev->dev, "%s: rekey device at port %d\n",
+ __func__, wusb_dev->port_idx);
+
+ if (wusb_dev_set_gtk(wusbhc, wusb_dev) < 0) {
+ dev_err(&wusb_dev->usb_dev->dev, "%s: rekey device at port %d failed\n",
+ __func__, wusb_dev->port_idx);
+ }
+ wusb_dev_put(wusb_dev);
+ }
- queue_work(wusbd, &wusbhc->gtk_rekey_done_work);
+ /* Switch the host controller to use the new GTK. */
+ mutex_lock(&wusbhc->mutex);
+ wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
+ &wusbhc->gtk.descr.bKeyData, key_size);
+ mutex_unlock(&wusbhc->mutex);
}
/**
*/
void wusbhc_gtk_rekey(struct wusbhc *wusbhc)
{
- static const size_t key_size = sizeof(wusbhc->gtk.data);
- int p;
-
- wusbhc_generate_gtk(wusbhc);
-
- for (p = 0; p < wusbhc->ports_max; p++) {
- struct wusb_dev *wusb_dev;
-
- wusb_dev = wusbhc->port[p].wusb_dev;
- if (!wusb_dev || !wusb_dev->usb_dev || !wusb_dev->usb_dev->authenticated)
- continue;
-
- usb_fill_control_urb(wusb_dev->set_gtk_urb, wusb_dev->usb_dev,
- usb_sndctrlpipe(wusb_dev->usb_dev, 0),
- (void *)wusb_dev->set_gtk_req,
- &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
- wusbhc_set_gtk_callback, wusbhc);
- if (usb_submit_urb(wusb_dev->set_gtk_urb, GFP_KERNEL) == 0)
- wusbhc->pending_set_gtks++;
- }
- if (wusbhc->pending_set_gtks == 0)
- wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
+ /*
+ * We need to submit a URB to the downstream WUSB devices in order to
+ * change the group key. This can't be done while holding the
+ * wusbhc->mutex since that is also taken in the urb_enqueue routine
+ * and will cause a deadlock. Instead, queue a work item to do
+ * it when the lock is not held
+ */
+ queue_work(wusbd, &wusbhc->gtk_rekey_work);
}
projects / linux-drm-fsl-dcu.git / blobdiff