diff options
Diffstat (limited to 'vendor/golang.org/x/image/tiff/reader.go')
| -rw-r--r-- | vendor/golang.org/x/image/tiff/reader.go | 33 |
1 files changed, 28 insertions, 5 deletions
diff --git a/vendor/golang.org/x/image/tiff/reader.go b/vendor/golang.org/x/image/tiff/reader.go index 45cc056f4..f31569b6d 100644 --- a/vendor/golang.org/x/image/tiff/reader.go +++ b/vendor/golang.org/x/image/tiff/reader.go @@ -8,13 +8,13 @@ package tiff // import "golang.org/x/image/tiff" import ( + "bytes" "compress/zlib" "encoding/binary" "fmt" "image" "image/color" "io" - "io/ioutil" "math" "golang.org/x/image/ccitt" @@ -579,6 +579,11 @@ func newDecoder(r io.Reader) (*decoder, error) { default: return nil, UnsupportedError("color model") } + if d.firstVal(tPhotometricInterpretation) != pRGB { + if len(d.features[tBitsPerSample]) != 1 { + return nil, UnsupportedError("extra samples") + } + } return d, nil } @@ -629,6 +634,13 @@ func Decode(r io.Reader) (img image.Image, err error) { blockWidth = int(d.firstVal(tTileWidth)) blockHeight = int(d.firstVal(tTileLength)) + // The specification says that tile widths and lengths must be a multiple of 16. + // We currently permit invalid sizes, but reject anything too small to limit the + // amount of work a malicious input can force us to perform. + if blockWidth < 8 || blockHeight < 8 { + return nil, FormatError("tile size is too small") + } + if blockWidth != 0 { blocksAcross = (d.config.Width + blockWidth - 1) / blockWidth } @@ -681,6 +693,11 @@ func Decode(r io.Reader) (img image.Image, err error) { } } + if blocksAcross == 0 || blocksDown == 0 { + return + } + // Maximum data per pixel is 8 bytes (RGBA64). + blockMaxDataSize := int64(blockWidth) * int64(blockHeight) * 8 for i := 0; i < blocksAcross; i++ { blkW := blockWidth if !blockPadding && i == blocksAcross-1 && d.config.Width%blockWidth != 0 { @@ -708,15 +725,15 @@ func Decode(r io.Reader) (img image.Image, err error) { inv := d.firstVal(tPhotometricInterpretation) == pWhiteIsZero order := ccittFillOrder(d.firstVal(tFillOrder)) r := ccitt.NewReader(io.NewSectionReader(d.r, offset, n), order, ccitt.Group3, blkW, blkH, &ccitt.Options{Invert: inv, Align: false}) - d.buf, err = ioutil.ReadAll(r) + d.buf, err = readBuf(r, d.buf, blockMaxDataSize) case cG4: inv := d.firstVal(tPhotometricInterpretation) == pWhiteIsZero order := ccittFillOrder(d.firstVal(tFillOrder)) r := ccitt.NewReader(io.NewSectionReader(d.r, offset, n), order, ccitt.Group4, blkW, blkH, &ccitt.Options{Invert: inv, Align: false}) - d.buf, err = ioutil.ReadAll(r) + d.buf, err = readBuf(r, d.buf, blockMaxDataSize) case cLZW: r := lzw.NewReader(io.NewSectionReader(d.r, offset, n), lzw.MSB, 8) - d.buf, err = ioutil.ReadAll(r) + d.buf, err = readBuf(r, d.buf, blockMaxDataSize) r.Close() case cDeflate, cDeflateOld: var r io.ReadCloser @@ -724,7 +741,7 @@ func Decode(r io.Reader) (img image.Image, err error) { if err != nil { return nil, err } - d.buf, err = ioutil.ReadAll(r) + d.buf, err = readBuf(r, d.buf, blockMaxDataSize) r.Close() case cPackBits: d.buf, err = unpackBits(io.NewSectionReader(d.r, offset, n)) @@ -748,6 +765,12 @@ func Decode(r io.Reader) (img image.Image, err error) { return } +func readBuf(r io.Reader, buf []byte, lim int64) ([]byte, error) { + b := bytes.NewBuffer(buf[:0]) + _, err := b.ReadFrom(io.LimitReader(r, lim)) + return b.Bytes(), err +} + func init() { image.RegisterFormat("tiff", leHeader, Decode, DecodeConfig) image.RegisterFormat("tiff", beHeader, Decode, DecodeConfig) |