Re: [PATCH RFC v6 4/5] iio: osf: add authenticated stream parser

[Andy Shevchenko]

On Mon, Jun 29, 2026 at 04:13:36AM +0900, Jinseob Kim wrote:
> Add a UART byte-stream parser for Open Sensor Fusion frames.
> 
> The parser searches for the OSF0 wire magic, keeps partial frames
> buffered, checks header length and payload bounds, and passes complete
> candidate frames to the core decoder.
> 
> Rejected candidate frames drop only the current head byte before
> resynchronizing, so a corrupted unauthenticated payload length cannot
> make the parser skip later valid frames.

...

> +#define OSF_STREAM_MAGIC_LEN	4
> +#define OSF_STREAM_MAX_PAYLOAD_LEN				\
> +	(OSF_STREAM_MAX_FRAME_LEN - OSF_FRAME_HEADER_LEN - OSF_FRAME_CRC_LEN)
> +
> +static const u8 osf_stream_magic[OSF_STREAM_MAGIC_LEN] = {
> +	'O', 'S', 'F', '0',
> +};

You have already this in the header (as FourCC), use that.

...

> +static size_t osf_stream_discard_to_magic(struct osf_stream *stream)
> +{
> +	size_t old_len = stream->len;
> +	size_t match_len;

> +	size_t i;
> +
> +	for (i = 0; i < stream->len; i++) {

	for (size_t i = 0; i < stream->len; i++) {

> +		match_len = stream->len - i;
> +		if (match_len > OSF_STREAM_MAGIC_LEN)
> +			match_len = OSF_STREAM_MAGIC_LEN;
> +
> +		if (osf_stream_magic_match(stream->buf + i, match_len)) {
> +			if (i)
> +				osf_stream_discard(stream, i);
> +			return i;
> +		}
> +	}
> +
> +	stream->len = 0;
> +	return old_len;
> +}

...

I stop here, because it's obvious that you neglected and ignored my previous
reviews. No explanation given, nothing. This is not how you should interact
with the community.

Come again when each of the given comment will be either addressed or argued.

-- 
With Best Regards,
Andy Shevchenko