Decode Array - Panic: Allocation size out of range Error

[brianshih1]

Hello! I've been using Golang's fuzzer to test how ParseBytes deal with data that doesn't match the schema. I've reproduced an edge case where ParseBytes panics with panic: runtime: allocation size out of range. Here is the code:

package main

import "github.com/hamba/avro/v2"

func main() {
	rawSchema := []byte("{\"items\":{\"type\":\"boolean\"},\"type\":\"array\"}")

	schema, _ := avro.ParseBytes(rawSchema)

	data := []byte("\x02\x00\xe9\xe9\xe9\xe9\xe9\xe9\xe9\xe9\x00")
	var container any
	avro.Unmarshal(schema, data, &container)
}

This is the line of code that leads to the error. The size is 29787588086545014 while the maxAlloc size is const maxAlloc untyped int = (1 << heapAddrBits) - (1-_64bit)*1 // 281474976710656. Perhaps we should do a check here and return an error if it exceeds the maxAlloc size?

In my opinion ParseBytes should never panic and should instead return an error when dealing with invalid data.

[brianshih1]

PR to fix it: #374