| Message ID | 20211027093529.30896-2-johan@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 907767da8f3a925b060c740e0b5c92ea7dbec440 |
| Headers | show |
| Series | comedi: misc fixes | expand |
On 27/10/2021 10:35, Johan Hovold wrote: > The driver uses endpoint-sized USB transfer buffers but had no sanity > checks on the sizes. This can lead to zero-size-pointer dereferences or > overflowed transfer buffers in ni6501_port_command() and > ni6501_counter_command() if a (malicious) device has smaller max-packet > sizes than expected (or when doing descriptor fuzz testing). > > Add the missing sanity checks to probe(). > > Fixes: a03bb00e50ab ("staging: comedi: add NI USB-6501 support") > Cc: stable@vger.kernel.org # 3.18 > Cc: Luca Ellero <luca.ellero@brickedbrain.com> > Signed-off-by: Johan Hovold <johan@kernel.org> > --- > drivers/comedi/drivers/ni_usb6501.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/comedi/drivers/ni_usb6501.c b/drivers/comedi/drivers/ni_usb6501.c > index 5b6d9d783b2f..c42987b74b1d 100644 > --- a/drivers/comedi/drivers/ni_usb6501.c > +++ b/drivers/comedi/drivers/ni_usb6501.c > @@ -144,6 +144,10 @@ static const u8 READ_COUNTER_RESPONSE[] = {0x00, 0x01, 0x00, 0x10, > 0x00, 0x00, 0x00, 0x02, > 0x00, 0x00, 0x00, 0x00}; > > +/* Largest supported packets */ > +static const size_t TX_MAX_SIZE = sizeof(SET_PORT_DIR_REQUEST); > +static const size_t RX_MAX_SIZE = sizeof(READ_PORT_RESPONSE); > + > enum commands { > READ_PORT, > WRITE_PORT, > @@ -501,6 +505,12 @@ static int ni6501_find_endpoints(struct comedi_device *dev) > if (!devpriv->ep_rx || !devpriv->ep_tx) > return -ENODEV; > > + if (usb_endpoint_maxp(devpriv->ep_rx) < RX_MAX_SIZE) > + return -ENODEV; > + > + if (usb_endpoint_maxp(devpriv->ep_tx) < TX_MAX_SIZE) > + return -ENODEV; > + > return 0; > } > > Looks good, thanks! Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
diff --git a/drivers/comedi/drivers/ni_usb6501.c b/drivers/comedi/drivers/ni_usb6501.c index 5b6d9d783b2f..c42987b74b1d 100644 --- a/drivers/comedi/drivers/ni_usb6501.c +++ b/drivers/comedi/drivers/ni_usb6501.c @@ -144,6 +144,10 @@ static const u8 READ_COUNTER_RESPONSE[] = {0x00, 0x01, 0x00, 0x10, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00}; +/* Largest supported packets */ +static const size_t TX_MAX_SIZE = sizeof(SET_PORT_DIR_REQUEST); +static const size_t RX_MAX_SIZE = sizeof(READ_PORT_RESPONSE); + enum commands { READ_PORT, WRITE_PORT, @@ -501,6 +505,12 @@ static int ni6501_find_endpoints(struct comedi_device *dev) if (!devpriv->ep_rx || !devpriv->ep_tx) return -ENODEV; + if (usb_endpoint_maxp(devpriv->ep_rx) < RX_MAX_SIZE) + return -ENODEV; + + if (usb_endpoint_maxp(devpriv->ep_tx) < TX_MAX_SIZE) + return -ENODEV; + return 0; }
The driver uses endpoint-sized USB transfer buffers but had no sanity checks on the sizes. This can lead to zero-size-pointer dereferences or overflowed transfer buffers in ni6501_port_command() and ni6501_counter_command() if a (malicious) device has smaller max-packet sizes than expected (or when doing descriptor fuzz testing). Add the missing sanity checks to probe(). Fixes: a03bb00e50ab ("staging: comedi: add NI USB-6501 support") Cc: stable@vger.kernel.org # 3.18 Cc: Luca Ellero <luca.ellero@brickedbrain.com> Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/comedi/drivers/ni_usb6501.c | 10 ++++++++++ 1 file changed, 10 insertions(+)