USB: hub: fix SS max number of ports
Add define for the maximum number of ports on a SuperSpeed hub as per
USB 3.1 spec Table 10-5, and use it when verifying the retrieved hub
descriptor.
This specifically avoids benign attempts to update the DeviceRemovable
mask for non-existing ports (should we get that far).
Fixes: dbe79bbe9dcb ("USB 3.0 Hub Changes")
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index f77a4eb..b8bb20d 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1336,7 +1336,13 @@
if (ret < 0) {
message = "can't read hub descriptor";
goto fail;
- } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
+ }
+
+ maxchild = USB_MAXCHILDREN;
+ if (hub_is_superspeed(hdev))
+ maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
+
+ if (hub->descriptor->bNbrPorts > maxchild) {
message = "hub has too many ports!";
ret = -ENODEV;
goto fail;
diff --git a/include/uapi/linux/usb/ch11.h b/include/uapi/linux/usb/ch11.h
index 361297e..576c704e 100644
--- a/include/uapi/linux/usb/ch11.h
+++ b/include/uapi/linux/usb/ch11.h
@@ -22,6 +22,9 @@
*/
#define USB_MAXCHILDREN 31
+/* See USB 3.1 spec Table 10-5 */
+#define USB_SS_MAXPORTS 15
+
/*
* Hub request types
*/