linux-kernel - [ 032/122] USB: Disable LPM while the device is unconfigured.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20120807221951.137841680@linuxfoundation.org>
Date:	Tue,  7 Aug 2012 15:25:20 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	Greg KH <gregkh@...uxfoundation.org>,
	torvalds@...ux-foundation.org, akpm@...ux-foundation.org,
	alan@...rguk.ukuu.org.uk,
	Sarah Sharp <sarah.a.sharp@...ux.intel.com>
Subject: [ 032/122] USB: Disable LPM while the device is unconfigured.

From: Greg KH <gregkh@...uxfoundation.org>

3.5-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Sarah Sharp <sarah.a.sharp@...ux.intel.com>

commit 9cf65991dd93ac3d5f97f536171c388918b7c1a9 upstream.

The USB 3.0 Set/Clear Feature U1/U2 Enable cannot be sent to a device in
the Default or Addressed state.  It can only be sent to a configured
device.  Change the USB core to initialize the LPM disable count to 1
(disabled), which reflects this limitation.

Change usb_set_configuration() to ensure that if the device is
unconfigured on entry, usb_lpm_disable() is not called.  This avoids
sending the Clear Feature U1/U2 when the device is in the Addressed
state.  When usb_set_configuration() exits with a successfully installed
configuration, usb_lpm_enable() will be called.

Once the new configuration is installed, make sure
usb_set_configuration() only calls usb_enable_lpm() if the device moved
to the Configured state.  If we have unconfigured the device by sending
it a Set Configuration for config 0, don't enable LPM.

This commit should be backported to kernels as old as 3.5, that contain
the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB
3.0 LPM in critical sections."

Signed-off-by: Sarah Sharp <sarah.a.sharp@...ux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/usb/core/message.c |    7 ++++---
 drivers/usb/core/usb.c     |    1 +
 2 files changed, 5 insertions(+), 3 deletions(-)

--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1791,14 +1791,15 @@ free_interfaces:
 	 * installed, so that the xHCI driver can recalculate the U1/U2
 	 * timeouts.
 	 */
-	if (usb_disable_lpm(dev)) {
+	if (dev->actconfig && usb_disable_lpm(dev)) {
 		dev_err(&dev->dev, "%s Failed to disable LPM\n.", __func__);
 		mutex_unlock(hcd->bandwidth_mutex);
 		return -ENOMEM;
 	}
 	ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL);
 	if (ret < 0) {
-		usb_enable_lpm(dev);
+		if (dev->actconfig)
+			usb_enable_lpm(dev);
 		mutex_unlock(hcd->bandwidth_mutex);
 		usb_autosuspend_device(dev);
 		goto free_interfaces;
@@ -1818,7 +1819,7 @@ free_interfaces:
 	if (!cp) {
 		usb_set_device_state(dev, USB_STATE_ADDRESS);
 		usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
-		usb_enable_lpm(dev);
+		/* Leave LPM disabled while the device is unconfigured. */
 		mutex_unlock(hcd->bandwidth_mutex);
 		usb_autosuspend_device(dev);
 		goto free_interfaces;
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -396,6 +396,7 @@ struct usb_device *usb_alloc_dev(struct
 	dev->dev.dma_mask = bus->controller->dma_mask;
 	set_dev_node(&dev->dev, dev_to_node(bus->controller));
 	dev->state = USB_STATE_ATTACHED;
+	dev->lpm_disable_count = 1;
 	atomic_set(&dev->urbnum, 0);
 
 	INIT_LIST_HEAD(&dev->ep0.urb_list);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/