local: fix incorrect conversion between integer types

backend/local/metadata.go

@@ -2,6 +2,7 @@ package local
 
 import (
 	"fmt"
+	"math"
 	"os"
 	"runtime"
 	"strconv"
@@ -128,11 +129,13 @@ func (o *Object) writeMetadataToFile(m fs.Metadata) (outErr error) {
 	}
 	mode, hasMode := o.parseMetadataInt(m, "mode", 8)
 	if hasMode {
+		if mode >= 0 && uint(mode) <= math.MaxUint32 {
 			err = os.Chmod(o.path, os.FileMode(mode))
 			if err != nil {
 				outErr = fmt.Errorf("failed to change permissions: %w", err)
 			}
 		}
+	}
 	// FIXME not parsing rdev yet
 	return outErr
 }