Re: [PATCH 09/15] common: tlv: Add TLV-Signature support

[Jonas Rebmann <jre@pengutronix.de>]

Hi Ahmad,

Just answering to what I don't immediately apply for v2:

On 2025-10-22 12:00, Ahmad Fatoum wrote:
>> +/*
>> + * Retrieve length of header+TLVs (offset of spki hash part of signature if available)
>> + */
>> +
>> +static inline size_t tlv_spki_hash_offset(const struct tlv_header *header)
>> +{
>> +	size_t ret = size_add(sizeof(struct tlv_header), get_unaligned_be32(&header->length_tlv));
>>   
>>   	return ret; /* SIZE_MAX on overflow */
> 
> Shouldn't you then check for SIZE_MAX at callsites?

I chose not to implement this check in all places using those
size/offset helpers.

In "[PATCH 01/15] common: clean up TLV code", I check early in the TLV
handling, that tlv_total_len() doesn't overflow. Later on, it is
guaranteed that calls to tlv_total_len(), tlv_spki_hash_offset() and the
such cannot overflow.

If I where to check at callsites of tlv_spki_hash_offset() I'd need to
check at all callsites of all TLV size/offset helperss, which seemed
unnecessary.

What do you think?

Regards,
Jonas

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