diff options
Diffstat (limited to 'src/encoding')
-rw-r--r-- | src/encoding/binary/varint.go | 5 | ||||
-rw-r--r-- | src/encoding/binary/varint_test.go | 18 |
2 files changed, 15 insertions, 8 deletions
diff --git a/src/encoding/binary/varint.go b/src/encoding/binary/varint.go index bcb8ac9a45..38af61075c 100644 --- a/src/encoding/binary/varint.go +++ b/src/encoding/binary/varint.go @@ -106,13 +106,13 @@ var overflow = errors.New("binary: varint overflows a 64-bit integer") func ReadUvarint(r io.ByteReader) (uint64, error) { var x uint64 var s uint - for i := 0; ; i++ { + for i := 0; i < MaxVarintLen64; i++ { b, err := r.ReadByte() if err != nil { return x, err } if b < 0x80 { - if i > 9 || i == 9 && b > 1 { + if i == 9 && b > 1 { return x, overflow } return x | uint64(b)<<s, nil @@ -120,6 +120,7 @@ func ReadUvarint(r io.ByteReader) (uint64, error) { x |= uint64(b&0x7f) << s s += 7 } + return x, overflow } // ReadVarint reads an encoded signed integer from r and returns it as an int64. diff --git a/src/encoding/binary/varint_test.go b/src/encoding/binary/varint_test.go index ca411ecbd6..6ef4c99505 100644 --- a/src/encoding/binary/varint_test.go +++ b/src/encoding/binary/varint_test.go @@ -121,21 +121,27 @@ func TestBufferTooSmall(t *testing.T) { } } -func testOverflow(t *testing.T, buf []byte, n0 int, err0 error) { +func testOverflow(t *testing.T, buf []byte, x0 uint64, n0 int, err0 error) { x, n := Uvarint(buf) if x != 0 || n != n0 { t.Errorf("Uvarint(%v): got x = %d, n = %d; want 0, %d", buf, x, n, n0) } - x, err := ReadUvarint(bytes.NewReader(buf)) - if x != 0 || err != err0 { - t.Errorf("ReadUvarint(%v): got x = %d, err = %s; want 0, %s", buf, x, err, err0) + r := bytes.NewReader(buf) + len := r.Len() + x, err := ReadUvarint(r) + if x != x0 || err != err0 { + t.Errorf("ReadUvarint(%v): got x = %d, err = %s; want %d, %s", buf, x, err, x0, err0) + } + if read := len - r.Len(); read > MaxVarintLen64 { + t.Errorf("ReadUvarint(%v): read more than MaxVarintLen64 bytes, got %d", buf, read) } } func TestOverflow(t *testing.T) { - testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x2}, -10, overflow) - testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x1, 0, 0}, -13, overflow) + testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x2}, 0, -10, overflow) + testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x1, 0, 0}, 0, -13, overflow) + testOverflow(t, []byte{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}, 1<<64-1, 0, overflow) // 11 bytes, should overflow } func TestNonCanonicalZero(t *testing.T) { |