The following commit has been merged into the perf/urgent branch of tip:

Commit-ID: 38df15cb4ce149ce3648d2a9ccc0140afa71fc02 Gitweb: https://git.kernel.org/tip/38df15cb4ce149ce3648d2a9ccc0140afa71fc02 Author: Anant Thazhemadam anant.thazhemadam@gmail.com AuthorDate: Sat, 10 Oct 2020 13:59:32 +05:30 Committer: Greg Kroah-Hartman gregkh@linuxfoundation.org CommitterDate: Sat, 17 Oct 2020 08:31:21 +02:00

staging: comedi: check validity of wMaxPacketSize of usb endpoints found

commit e1f13c879a7c21bd207dc6242455e8e3a1e88b40 upstream.

While finding usb endpoints in vmk80xx_find_usb_endpoints(), check if wMaxPacketSize = 0 for the endpoints found.

Some devices have isochronous endpoints that have wMaxPacketSize = 0 (as required by the USB-2 spec). However, since this doesn't apply here, wMaxPacketSize = 0 can be considered to be invalid.

Reported-by: syzbot+009f546aa1370056b1c2@syzkaller.appspotmail.com Tested-by: syzbot+009f546aa1370056b1c2@syzkaller.appspotmail.com Signed-off-by: Anant Thazhemadam anant.thazhemadam@gmail.com Cc: stable stable@vger.kernel.org Link: https://lore.kernel.org/r/20201010082933.5417-1-anant.thazhemadam@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/staging/comedi/drivers/vmk80xx.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/drivers/staging/comedi/drivers/vmk80xx.c b/drivers/staging/comedi/drivers/vmk80xx.c index 65dc6c5..7956abc 100644 --- a/drivers/staging/comedi/drivers/vmk80xx.c +++ b/drivers/staging/comedi/drivers/vmk80xx.c @@ -667,6 +667,9 @@ static int vmk80xx_find_usb_endpoints(struct comedi_device *dev) if (!devpriv->ep_rx || !devpriv->ep_tx) return -ENODEV;

+ if (!usb_endpoint_maxp(devpriv->ep_rx) || !usb_endpoint_maxp(devpriv->ep_tx)) + return -EINVAL; + return 0; }