Ceph » rbd

I'm running a simple test script to reproduce this:

import rados
import rbd
cluster = rados.Rados(conffile='/etc/ceph/ceph.conf')
cluster.connect()
ioctx = cluster.open_ioctx('images')
image = rbd.Image(ioctx, '41a6aadf-c655-49c8-b77d-eedd356f5349')
stat = image.stat()
print stat['size'] == image.size()
print stat['block_name_prefix']
print len(stat['block_name_prefix'])

and I am seeing varying results like

$ python test.py
Traceback (most recent call last):
  File "test.py", line 7, in <module>
    stat = image.stat()
  File "rbd.pyx", line 1124, in rbd.Image.stat (/build/ceph-XmVvyr/ceph-10.2.2/src/build/rbd.c:10803)
  File "rbd.pyx", line 433, in rbd.decode_cstr (/build/ceph-XmVvyr/ceph-10.2.2/src/build/rbd.c:2440)
  File "/usr/lib/python2.7/encodings/utf_8.py", line 16, in decode
    return codecs.utf_8_decode(input, errors, True)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xaf in position 24: invalid start byte
$ python test.py
True
rbd_data.3d98fcf378d97c0(
26
$ python test.py
True
rbd_data.3d98fcf378d97c0|
26

Looking at the code in src/pybind/rbd/rbd.pyx it seems like decode_cstr(info.block_name_prefix) is being called assuming that block_name_prefix is a null-terminated string, which it isn't.