The attached file produces the following stacktrace when opened via `tarfile.open`, on Python 3.7.5rc1:

```
$ cat test.py 
import sys
import tarfile

tarfile.open(sys.argv[1])
$ python3 test.py ./crash-83a6e7d4b810c6a0bd4fd9dfd6a0b36550034ccf
Traceback (most recent call last):
  File "test.py", line 4, in <module>
    tarfile.open(sys.argv[1])
  File "/usr/lib/python3.7/tarfile.py", line 1573, in open
    return func(name, "r", fileobj, **kwargs)
  File "/usr/lib/python3.7/tarfile.py", line 1645, in gzopen
    t = cls.taropen(name, mode, fileobj, **kwargs)
  File "/usr/lib/python3.7/tarfile.py", line 1621, in taropen
    return cls(name, mode, fileobj, **kwargs)
  File "/usr/lib/python3.7/tarfile.py", line 1484, in __init__
    self.firstmember = self.next()
  File "/usr/lib/python3.7/tarfile.py", line 2289, in next
    tarinfo = self.tarinfo.fromtarfile(self)
  File "/usr/lib/python3.7/tarfile.py", line 1097, in fromtarfile
    return obj._proc_member(tarfile)
  File "/usr/lib/python3.7/tarfile.py", line 1119, in _proc_member
    return self._proc_pax(tarfile)
  File "/usr/lib/python3.7/tarfile.py", line 1230, in _proc_pax
    match = regex.match(buf, pos)
OverflowError: Python int too large to convert to C ssize
```

The file is not a valid tar file:

$ tar xf crash-83a6e7d4b810c6a0bd4fd9dfd6a0b36550034ccf

gzip: stdin: invalid compressed data--crc error

gzip: stdin: invalid compressed data--length error
tar: This does not look like a tar archive
tar: Skipping to next header
tar: Child returned status 1
tar: Error is not recoverable: exiting now