I'm confused by fact that this verb irregular and is spelled the same in 1-3 forms.
Exactly. Your readers will be confused too, if you write something like “examine the read data”.
Grammatically, the read data is fine. Practically, it is a confusing mess. Treat it as you would treat code that's technically correct but confusing: rewrite it.
For your amusement: Some other past participles that are exactly identical to the present tense are bet, burst, cut, hit, hurt, let, put, run, set, shut, and split. Some of these can be used before a noun (some burst pipes, the hurt children), but most aren’t normally used that way in practice (the hit batter charged the mound would be strange). Read is not alone, though it is especially bothersome for programmers.
Workarounds: An adjective or past participle with complements of its own can go after a noun: the people hurt in the blast, the amount bet on the first race, batters hit by wild pitches, the data read from the socket, the data read so far.
However, it is probably best to just drop the confusing word read and say the data from the socket or all the input so far or the data in 'x' where x is a variable name.