x/image/tiff: index out of range

[dvyukov]

The following program crashes:

panic: runtime error: index out of range
goroutine 1 [running]:
golang.org/x/image/tiff.(*decoder).ifdUint(0xc208072000, 0xc208074084, 0xc, 0x3c, 0x0, 0x0, 0x0, 0x0, 0x0)
    /ssd/src/gopath/src/golang.org/x/image/tiff/reader.go:75 +0x6eb
golang.org/x/image/tiff.(*decoder).parseIFD(0xc208072000, 0xc208074084, 0xc, 0x3c, 0x0, 0x0)
    /ssd/src/gopath/src/golang.org/x/image/tiff/reader.go:125 +0x122
golang.org/x/image/tiff.newDecoder(0x7f96aa807260, 0xc20800e440, 0x0, 0x0, 0x0)
    /ssd/src/gopath/src/golang.org/x/image/tiff/reader.go:415 +0x6d7
golang.org/x/image/tiff.Decode(0x7f96aa807260, 0xc20800e440, 0x0, 0x0, 0x0, 0x0)
    /ssd/src/gopath/src/golang.org/x/image/tiff/reader.go:517 +0x6b
main.main()
    /tmp/tiff.go:9 +0xa6

package main

import (
    "strings"
    "golang.org/x/image/tiff"
)

func main() {
    tiff.Decode(strings.NewReader(data))
}

var data = "II*\x002\x01\x00\x00000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "000000\x10\x00000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000" +
    "\x17\x01000000000000000000" +
    "00000000000000000000" +
    "00000000000000000000"

on commit b2f48f3f517c959ebf11245aa7bf39b127497e9c

[dvyukov]

/cc @bsiegert @chai2010 @osocurioso

[chai2010]

I sent a https://go-review.googlesource.com/#/c/9414/ for this issue.
But i think we need do more check for these similar issue.