USB: CDC ACM: Fix NULL pointer dereference

If a device specifies zero endpoints in its interface descriptor,
the kernel oopses in acm_probe(). Even though that's clearly an
invalid descriptor, we should test wether we have all endpoints.
This is especially bad as this oops can be triggered by just
plugging a USB device in.

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sven Schnelle 2012-08-17 21:43:43 +02:00 committed by Greg Kroah-Hartman
parent 83957df21d
commit 99f347caa4

View file

@ -1104,7 +1104,8 @@ skip_normal_probe:
}
if (data_interface->cur_altsetting->desc.bNumEndpoints < 2)
if (data_interface->cur_altsetting->desc.bNumEndpoints < 2 ||
control_interface->cur_altsetting->desc.bNumEndpoints == 0)
return -EINVAL;
epctrl = &control_interface->cur_altsetting->endpoint[0].desc;