Commit c24e4aac authored by Gerd Hoffmann's avatar Gerd Hoffmann
Browse files

usb-hub: limit chain length 



USB supports up to 5 hubs chained.
Catch attempts to chain more.

Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
parent 4b7b2afa

hw/usb.h

+1 −0
Original line number Diff line number Diff line
@@ -337,6 +337,7 @@ typedef struct USBPortOps { 
struct USBPort {

    USBDevice *dev;

    int speedmask;

    int hubcount;

    char path[16];

    USBPortOps *ops;

    void *opaque;

hw/usb/bus.c

+2 −0
Original line number Diff line number Diff line
@@ -341,8 +341,10 @@ void usb_port_location(USBPort *downstream, USBPort *upstream, int portnr) 
    if (upstream) {

        snprintf(downstream->path, sizeof(downstream->path), "%s.%d",

                 upstream->path, portnr);

        downstream->hubcount = upstream->hubcount + 1;

    } else {

        snprintf(downstream->path, sizeof(downstream->path), "%d", portnr);

        downstream->hubcount = 0;

    }

}

hw/usb/dev-hub.c

+6 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include "trace.h"

#include "hw/usb.h"

#include "hw/usb/desc.h"

#include "qemu/error-report.h"



#define NUM_PORTS 8
@@ -514,6 +515,11 @@ static int usb_hub_initfn(USBDevice *dev) 
    USBHubPort *port;

    int i;



    if (dev->port->hubcount == 5) {

        error_report("usb hub chain too deep");

        return -1;

    }



    usb_desc_create_serial(dev);

    usb_desc_init(dev);

    s->intr = usb_ep_get(dev, USB_TOKEN_IN, 1);