core/vm: no more recursive errors

core/vm/eof.go

@@ -89,7 +89,7 @@ type Container struct {
 	ContainerSections []*Container
 	ContainerCode     [][]byte
 	Data              []byte
-	DataSize          int // might be less than len(Data)
+	DataSize          int // might be more than len(Data)
 }
 
 // FunctionMetadata is an EOF function signature.
@@ -292,7 +292,10 @@ func (c *Container) unmarshalSubContainer(b []byte, isInitcode bool, topLevel bo
 			c := new(Container)
 			end := min(idx+size, len(b))
 			if err := c.unmarshalSubContainer(b[idx:end], isInitcode, false); err != nil {
-				return fmt.Errorf("%w for section %d", err, i)
+				if topLevel {
+					return fmt.Errorf("%w in sub container %d", err, i)
+				}
+				return err
 			}
 			container = append(container, c)
 			containerCode = append(containerCode, b[idx:end])

core/vm/validate.go

@@ -120,9 +120,15 @@ func validateCode(code []byte, section int, container *Container, jt *JumpTable,
 			if arg >= len(container.Types) {
 				return nil, fmt.Errorf("%w: arg %d, last %d, pos %d", ErrInvalidSectionArgument, arg, len(container.Types), i)
 			}
+			// TODO check if that is actually a problem
+			// JUMPF operand must point to a code section with equal or fewer number of outputs as the section in which it resides, or to a section with 0x80 as outputs (non-returning)
+			if container.Types[arg].Output > container.Types[section].Output {
+				return nil, fmt.Errorf("%w: arg %d, last %d, pos %d", ErrInvalidSectionArgument, arg, len(container.Types), i)
+			}
 			visitedCode[arg] = struct{}{}
 		case op == DATALOADN:
 			arg, _ := parseUint16(code[i+1:])
+			// TODO why are we checking this? We should just pad
 			if arg+32 > len(container.Data) {
 				return nil, fmt.Errorf("%w: arg %d, last %d, pos %d", ErrInvalidDataloadNArgument, arg, len(container.Data), i)
 			}