Patch "USB: hub: fix non-SS hub-descriptor handling" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

USB: hub: fix non-SS hub-descriptor handling

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
usb-hub-fix-non-ss-hub-descriptor-handling.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Johan Hovold <[email protected]>
Date: Wed, 10 May 2017 18:18:28 +0200
Subject: USB: hub: fix non-SS hub-descriptor handling

From: Johan Hovold <[email protected]>

commit bec444cd1c94c48df409a35ad4e5b143c245c3f7 upstream.

Add missing sanity check on the non-SuperSpeed hub-descriptor length in order to avoid parsing and leaking two bytes of uninitialised slab data through sysfs removable-attributes (or a compound-device debug statement).

Note that we only make sure that the DeviceRemovable field is always present (and specifically ignore the unused PortPwrCtrlMask field) in order to continue support any hubs with non-compliant descriptors. As a further safeguard, the descriptor buffer is also cleared.

---
 drivers/usb/core/hub.c |   13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

@@ -358,7 +358,8 @@ static void usb_set_lpm_parameters(struc
 }
 
 /* USB 2.0 spec Section 11.24.4.5 */
-static int get_hub_descriptor(struct usb_device *hdev, void *data)
+static int get_hub_descriptor(struct usb_device *hdev,
+		struct usb_hub_descriptor *desc)
 {
 	int i, ret, size;
 	unsigned dtype;

@@ -374,12 +375,16 @@ static int get_hub_descriptor(struct usb
 	for (i = 0; i < 3; i++) {
 		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
-			dtype << 8, 0, data, size,
+			dtype << 8, 0, desc, size,
 			USB_CTRL_GET_TIMEOUT);
 		if (hub_is_superspeed(hdev)) {
 			if (ret == size)
 				return ret;
-		} else if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2)) {
+		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
+			/* Make sure we have the DeviceRemovable field. */
+			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
+			if (ret < size)
+				return -EMSGSIZE;
 			return ret;
 		}
 	}

@@ -1299,7 +1304,7 @@ static int hub_configure(struct usb_hub
 	}
 	mutex_init(&hub->status_mutex);
 
-	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
+	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 	if (!hub->descriptor) {
 		ret = -ENOMEM;
 		goto fail;

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/usb-serial-io_ti-fix-div-by-zero-in-set_termios.patch queue-4.4/usb-hub-fix-non-ss-hub-descriptor-handling.patch queue-4.4/usb-serial-ftdi_sio-add-olimex-arm-usb-tiny-h-pids.patch queue-4.4/usb-serial-ftdi_sio-fix-setting-latency-for-unprivileged-users.patch queue-4.4/usb-iowarrior-fix-info-ioctl-on-big-endian-hosts.patch queue-4.4/watchdog-pcwd_usb-fix-null-deref-at-probe.patch queue-4.4/usb-serial-qcserial-add-more-lenovo-em74xx-device-ids.patch queue-4.4/usb-serial-option-add-telit-me910-support.patch queue-4.4/net-irda-irda-usb-fix-firmware-name-on-big-endian-hosts.patch queue-4.4/usbvision-fix-null-deref-at-probe.patch queue-4.4/usb-serial-mct_u232-fix-big-endian-baud-rate-handling.patch queue-4.4/usb-ehci-platform-fix-companion-device-leak.patch queue-4.4/mceusb-fix-null-deref-at-probe.patch queue-4.4/usb-hub-fix-ss-hub-descriptor-handling.patch queue-4.4/ath9k_htc-fix-null-deref-at-probe.patch