diff options
| author | Johan Hovold <johan@kernel.org> | 2021-10-25 13:45:31 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-10-26 19:10:18 +0200 |
| commit | 78cdfd62bd54af615fba9e3ca1ba35de39d3871d (patch) | |
| tree | 165b9a66a1797d25dc779a94ea295aae1df7c3fd /drivers/comedi | |
| parent | a23461c47482fc232ffc9b819539d1f837adf2b1 (diff) | |
comedi: vmk80xx: fix bulk-buffer overflow
The driver is using endpoint-sized buffers but must not assume that the
tx and rx buffers are of equal size or a malicious device could overflow
the slab-allocated receive buffer when doing bulk transfers.
Fixes: 985cafccbf9b ("Staging: Comedi: vmk80xx: Add k8061 support")
Cc: stable@vger.kernel.org # 2.6.31
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20211025114532.4599-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/comedi')
| -rw-r--r-- | drivers/comedi/drivers/vmk80xx.c | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/drivers/comedi/drivers/vmk80xx.c b/drivers/comedi/drivers/vmk80xx.c index f2c1572d0cd7..9c56918e3b76 100644 --- a/drivers/comedi/drivers/vmk80xx.c +++ b/drivers/comedi/drivers/vmk80xx.c @@ -159,22 +159,20 @@ static void vmk80xx_do_bulk_msg(struct comedi_device *dev) __u8 rx_addr; unsigned int tx_pipe; unsigned int rx_pipe; - size_t size; + size_t tx_size; + size_t rx_size; tx_addr = devpriv->ep_tx->bEndpointAddress; rx_addr = devpriv->ep_rx->bEndpointAddress; tx_pipe = usb_sndbulkpipe(usb, tx_addr); rx_pipe = usb_rcvbulkpipe(usb, rx_addr); - - /* - * The max packet size attributes of the K8061 - * input/output endpoints are identical - */ - size = usb_endpoint_maxp(devpriv->ep_tx); + tx_size = usb_endpoint_maxp(devpriv->ep_tx); + rx_size = usb_endpoint_maxp(devpriv->ep_rx); usb_bulk_msg(usb, tx_pipe, devpriv->usb_tx_buf, - size, NULL, devpriv->ep_tx->bInterval); - usb_bulk_msg(usb, rx_pipe, devpriv->usb_rx_buf, size, NULL, HZ * 10); + tx_size, NULL, devpriv->ep_tx->bInterval); + + usb_bulk_msg(usb, rx_pipe, devpriv->usb_rx_buf, rx_size, NULL, HZ * 10); } static int vmk80xx_read_packet(struct comedi_device *dev) |