USB: hub: fix non-SS hub-descriptor handling (bec444cd) · Commits · 戴 / test

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. Fixes: ("Linux-2.6.12-rc2") Cc: stable <stable@vger.kernel.org> # 2.6.12 Signed-off-by:

Johan Hovold <johan@kernel.org> Acked-by:

Alan Stern <stern@rowland.harvard.edu> Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hub.c

+9 −4

Original line number	Diff line number	Diff line
		@@ -362,7 +362,8 @@ static void usb_set_lpm_parameters(struct usb_device *udev)
		}

		/* 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;
		@@ -378,12 +379,16 @@ static int get_hub_descriptor(struct usb_device hdev, void data)
		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;
		}
		}
		@@ -1317,7 +1322,7 @@ static int hub_configure(struct usb_hub *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;

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