USB: wusbcore: fix NULL-deref at probe

commit 03ace948a4eb89d1cf51c06afdfc41ebca5fdb27 upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.

This specifically fixes the NULL-pointer dereference when probing HWA HC
devices.

Fixes: df3654236e31 ("wusb: add the Wire Adapter (WA) core")
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Cc: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/drivers/usb/wusbcore/wa-hc.c b/drivers/usb/wusbcore/wa-hc.c
index a09b65ebd9bb712d02060e760ff2c349bcdc2e77..2bb0fd3f342365d7e75392abe3b9d2d41a34dfd0 100644 (file)
--- a/drivers/usb/wusbcore/wa-hc.c
+++ b/drivers/usb/wusbcore/wa-hc.c
@@ -38,6 +38,9 @@ int wa_create(struct wahc *wa, struct usb_interface *iface)
        int result;
        struct device *dev = &iface->dev;
 
+       if (iface->cur_altsetting->desc.bNumEndpoints < 3)
+               return -ENODEV;
+
        result = wa_rpipes_create(wa);
        if (result < 0)
                goto error_rpipes_create;