cache: too much permissions

[jimen0]

1. Version of golangci-lint: golangci-lint --version: current HEAD: fd997edeeb4ac277823750d746394d80f03d7ec1
2. Config file: cat .golangci.yml: N/A
3. Go environment: go version && go env: N/A
4. Verbose output of running: golangci-lint run -v: N/A

While reading golangci-lint source code I found that the cache initialization method creates the directory using too many permissions:

golangci-lint/internal/cache/default.go

Lines 33 to 50 in 6a979fb

	// initDefaultCache does the work of finding the default cache
	// the first time Default is called.
	func initDefaultCache() {
	dir := DefaultDir()
	if err := os.MkdirAll(dir, 0777); err != nil {
	log.Fatalf("failed to initialize build cache at %s: %s\n", dir, err)
	}
	if _, err := os.Stat(filepath.Join(dir, "README")); err != nil {
	// Best effort.
	ioutil.WriteFile(filepath.Join(dir, "README"), []byte(cacheREADME), 0666)
	}
	c, err := Open(dir)
	if err != nil {
	log.Fatalf("failed to initialize build cache at %s: %s\n", dir, err)
	}
	defaultCache = c
	}

Are world executable and world-writable really needed? If not, I'd be open to creating a PR.

Thanks!

[jirfag]

Hi, good points, thank you