Fix bug in merkle/iavl_proof; TODO maybe read zero length slices as nil?

binary/binary.go

@@ -10,7 +10,8 @@ import (
 // TODO document and maybe make it configurable.
 const MaxBinaryReadSize = 21 * 1024 * 1024
 
-var ErrMaxBinaryReadSizeReached = errors.New("Error: max binary read size reached")
+var ErrBinaryReadSizeOverflow = errors.New("Error: binary read size overflow")
+var ErrBinaryReadSizeUnderflow = errors.New("Error: binary read size underflow")
 
 func ReadBinary(o interface{}, r io.Reader, n *int64, err *error) interface{} {
 	rv, rt := reflect.ValueOf(o), reflect.TypeOf(o)

binary/byteslice.go

@@ -2,6 +2,8 @@ package binary
 
 import (
 	"io"
+
+	. "github.com/tendermint/tendermint/common"
 )
 
 func WriteByteSlice(bz []byte, w io.Writer, n *int64, err *error) {
@@ -14,8 +16,12 @@ func ReadByteSlice(r io.Reader, n *int64, err *error) []byte {
 	if *err != nil {
 		return nil
 	}
-	if MaxBinaryReadSize < *n+int64(length) {
-		*err = ErrMaxBinaryReadSizeReached
+	if length < 0 {
+		*err = ErrBinaryReadSizeUnderflow
+		return nil
+	}
+	if MaxBinaryReadSize < MaxInt64(int64(length), *n+int64(length)) {
+		*err = ErrBinaryReadSizeOverflow
 		return nil
 	}
 
@@ -41,8 +47,12 @@ func ReadByteSlices(r io.Reader, n *int64, err *error) [][]byte {
 	if *err != nil {
 		return nil
 	}
-	if MaxBinaryReadSize < *n+int64(length) {
-		*err = ErrMaxBinaryReadSizeReached
+	if length < 0 {
+		*err = ErrBinaryReadSizeUnderflow
+		return nil
+	}
+	if MaxBinaryReadSize < MaxInt64(int64(length), *n+int64(length)) {
+		*err = ErrBinaryReadSizeOverflow
 		return nil
 	}
 

binary/reflect.go

@@ -274,7 +274,7 @@ func readReflectBinary(rv reflect.Value, rt reflect.Type, opts Options, r io.Rea
 						return
 					}
 					if MaxBinaryReadSize < *n {
-						*err = ErrMaxBinaryReadSizeReached
+						*err = ErrBinaryReadSizeOverflow
 						return
 					}
 				}

binary/reflect_test.go

@@ -456,7 +456,7 @@ func TestJSONFieldNames(t *testing.T) {
 func TestBadAlloc(t *testing.T) {
 	n, err := new(int64), new(error)
 	instance := new([]byte)
-	data := RandBytes(ByteSliceChunk * 100)
+	data := RandBytes(100 * 1024)
 	b := new(bytes.Buffer)
 	// this slice of data claims to be much bigger than it really is
 	WriteUvarint(uint(10000000000000000), b, n, err)

binary/string.go

@@ -1,6 +1,10 @@
 package binary
 
-import "io"
+import (
+	"io"
+
+	. "github.com/tendermint/tendermint/common"
+)
 
 // String
 
@@ -14,8 +18,12 @@ func ReadString(r io.Reader, n *int64, err *error) string {
 	if *err != nil {
 		return ""
 	}
-	if MaxBinaryReadSize < *n+int64(length) {
-		*err = ErrMaxBinaryReadSizeReached
+	if length < 0 {
+		*err = ErrBinaryReadSizeUnderflow
+		return ""
+	}
+	if MaxBinaryReadSize < MaxInt64(int64(length), *n+int64(length)) {
+		*err = ErrBinaryReadSizeOverflow
 		return ""
 	}