On 10/21/20 9:11 AM, Joakim Zhang wrote:
> I wonder if it's appropriate to ask this question here, why this RAW_DLC
> issue might run into some buffer overflow issue? Will it cause frames dropped
> finally?

On the wire the dlc for CAN-2.0 frames ca go from 0...15. In the RX-path the DLC
for CAN-2.0 frames is capped to 8.

So userspace only ever sees a max dlc of 8. This way you can loop over the
struct can_frame::data. If we pass the dlc of the wire uncapped, you may loop
until 15 :)

In the TX-path we currently drop CAN-2.0 frames with dlc >8.

regards,
Marc

-- 
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