Is there a better way to read unzipped data into a slice?

I'm reading gzip data from a http request like this:

gzr, err := gzip.NewReader(resp.Body)
handle(err)

And then conservatively allocating a slice for the unzipped data.

cl := resp.Header.Get("Content-Length")
icl, err := strconv.Atoi(cl)
handle(err)
ubs := make([]byte, icl*3)

And finally trimming the slice after reading

_, err = gzr.Read(ubs)
ubs = bytes.TrimRightFunc(ubs, sliceFunc)

Is there a better way to do this ?

For starters, .Read returns the numbers of bytes read, so you can do something like:

n, err = gzr.Read(ubs)
ubs = ubs[:n]

Also you can use a bytes.Buffer pool and do something like:

buf := getBufferFromPool()
io.Copy(buf, gzr)