whitelist crypto/rand Read from error checks (#1446)

rules/errors.go

@@ -89,6 +89,7 @@ func NewNoErrorCheck(id string, conf gosec.Config) (gosec.Rule, []ast.Node) {
 	whitelist.Add("io.PipeWriter", "CloseWithError")
 	whitelist.Add("hash.Hash", "Write")
 	whitelist.Add("os", "Unsetenv")
+	whitelist.Add("rand", "Read")
 
 	if configured, ok := conf[id]; ok {
 		if whitelisted, ok := configured.(map[string]interface{}); ok {

testutils/g104_samples.go

@@ -142,6 +142,17 @@ func main() {
 	b := createBuffer()
 	b.WriteString("*bytes.Buffer")
 }
+`}, 0, gosec.NewConfig()},
+		{[]string{`
+package main
+
+import "crypto/rand"
+
+func main() {
+	b := make([]byte, 8)
+	rand.Read(b)
+	_ = b
+}
 `}, 0, gosec.NewConfig()},
 	} // it shouldn't return any errors because all method calls are whitelisted by default