Nicolas Iooss 238b7bd91b usb: usbip: vudc: fix left shift overflow
In v_recv_cmd_submit(), urb_p->urb->pipe has the type unsigned int
(which is 32-bit long on x86_64) but 11<<30 results in a 34-bit integer.
Therefore the 2 leading bits are truncated and

    urb_p->urb->pipe &= ~(11 << 30);

has the same meaning as

    urb_p->urb->pipe &= ~(3 << 30);

This second statement seems to be how the code was intended to be
written, as PIPE_ constants have values between 0 and 3.

The overflow has been detected with a clang warning:

    drivers/usb/usbip/vudc_rx.c:145:27: warning: signed shift result
    (0x2C0000000) requires 35 bits to represent, but 'int' only has 32
    bits [-Wshift-overflow]
            urb_p->urb->pipe &= ~(11 << 30);
                                  ~~ ^  ~~

Fixes: 79c02cb1fd5c ("usbip: vudc: Add vudc_rx")
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-30 22:28:52 +02:00
..
2016-04-26 15:19:50 -07:00
2016-04-26 15:19:50 -07:00
2016-06-07 22:18:39 -07:00
2016-04-26 15:19:50 -07:00

TODO:
	- more discussion about the protocol
	- testing
	- review of the userspace interface
	- document the protocol

Please send patches for this code to Greg Kroah-Hartman <greg@kroah.com>