This is a note to let you know that I've just added the patch titled staging: comedi: check validity of wMaxPacketSize of usb endpoints to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. >From e1f13c879a7c21bd207dc6242455e8e3a1e88b40 Mon Sep 17 00:00:00 2001 From: Anant Thazhemadam <anant.thazhemadam@xxxxxxxxx> Date: Sat, 10 Oct 2020 13:59:32 +0530 Subject: staging: comedi: check validity of wMaxPacketSize of usb endpoints found 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@xxxxxxxxxxxxxxxxxxxxxxxxx Tested-by: syzbot+009f546aa1370056b1c2@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Anant Thazhemadam <anant.thazhemadam@xxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20201010082933.5417-1-anant.thazhemadam@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 65dc6c51037e..7956abcbae22 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; } -- 2.28.0