[PATCH 3.18 132/145] USB: wusbcore: fix NULL-deref at probe

Greg Kroah-Hartman
2017-04-16T11:02:50Z

From: Johan Hovold <johan@kernel.org>

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/wusbcore/wa-hc.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/usb/wusbcore/wa-hc.c
+++ b/drivers/usb/wusbcore/wa-hc.c
@@ -39,6 +39,9 @@ int wa_create(struct wahc *wa, struct us
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;