queue: Push() panics in v3.0.0
Author: ppai-plivoCreated Jan 28, 2021Updated May 19, 2025
Labelsbug
What is the issue you are having?
panic: runtime error: slice bounds out of range [1:0]
goroutine 1 [running]:
github.com/allegro/bigcache/v3/queue.(*BytesQueue).copy(...)
/Users/prashanthpai/go/pkg/mod/github.com/allegro/bigcache/[email protected]/queue/bytes_queue.go:157
github.com/allegro/bigcache/v3/queue.(*BytesQueue).push(0xc00010ef08, 0xc00010eefd, 0xb, 0xb, 0xb)
/Users/prashanthpai/go/pkg/mod/github.com/allegro/bigcache/[email protected]/queue/bytes_queue.go:142 +0x1a8
github.com/allegro/bigcache/v3/queue.(*BytesQueue).Push(0xc00010ef08, 0xc00010eefd, 0xb, 0xb, 0xc000100050, 0xc00010ef18, 0x1040f4a)
/Users/prashanthpai/go/pkg/mod/github.com/allegro/bigcache/[email protected]/queue/bytes_queue.go:100 +0xb2
main.main()
/Users/prashanthpai/bigcache-bug/main.go:7 +0x11cWhat is BigCache doing that it shouldn't?
It's panicking. I haven't looked deeper but the the most likely cause is the integer underflow (uint64) here which is hit when capacity passed to NewBytesQueue is 0:
https://github.com/allegro/bigcache/blob/55d48f4e069fd81755c7be002903253d961abe44/queue/bytes_queue.go#L251
This is a regression from 2.2.5 caused by https://github.com/allegro/bigcache/pull/236
Minimal, Complete, and Verifiable Example
package main
import "github.com/allegro/bigcache/v3/queue"
func main() {
q := queue.NewBytesQueue(0, 1024, true)
q.Push([]byte("hello world"))
}Environment:
$ go version
go version go1.15.2 darwin/amd64Source: allegro/bigcache