Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

nfc: port100: reject frames whose declared length exceeds the received data

port100_recv_response() passes the URB transfer buffer to port100_rx_frame_is_valid(), which checksums le16_to_cpu(frame->datalen) bytes of frame->data. datalen is a 16-bit field supplied by the device and is never checked against the number of bytes actually received (urb->actual_length), so a device reporting a datalen larger than the received frame makes port100_data_checksum() read out of bounds past the transfer buffer.

Reject a response whose declared frame size does not fit the received length before validating it.

Found by 0sec (https://0sec.ai) using automated source analysis; the missing bound is evident from source. Compile-tested.