[issue35974] os.DirEntry.inode() returns invalid value within Docker container

[Marat Sharafutdinov]

New submission from Marat Sharafutdinov <decaz89 at gmail.com>:

I'm trying to build Python 3.7.2 within official CentOS 7.6.1810 image (https://hub.docker.com/_/centos) and getting the following error during testing:

======================================================================
FAIL: test_attributes (test.test_os.TestScandir)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/src/python/Lib/test/test_os.py", line 3367, in test_attributes
    self.check_entry(entry, 'dir', True, False, False)
  File "/usr/src/python/Lib/test/test_os.py", line 3319, in check_entry
    os.stat(entry.path, follow_symlinks=False).st_ino)
AssertionError: 28093768 != 85098458

I guess this bug applies to Docker containers in general. For instance it's reproduced with the official Python 3.7.2-stretch image based on the Debian Stretch (https://hub.docker.com/_/python):

$ docker run --rm -it python:3.7.2-stretch
Python 3.7.2 (default, Feb  6 2019, 12:04:03) 
[GCC 6.3.0 20170516] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.mkdir('/test_dir')
>>> for entry in os.scandir('/'):
...   if entry.name == 'test_dir':
...     break
... 
>>> print(entry, entry.inode(), os.stat(entry.path, follow_symlinks=False).st_ino)
<DirEntry 'test_dir'> 23898155 85118011
>>> assert entry.inode() == os.stat(entry.path, follow_symlinks=False).st_ino
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AssertionError
>>> 

In case of using host volume when running container it works ok, - the problem occurs when using default Docker volume:

$ docker run --rm -it -v /home/decaz/workspace:/host_dir python:3.7.2-stretch
Python 3.7.2 (default, Feb  6 2019, 12:04:03) 
[GCC 6.3.0 20170516] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.mkdir('/host_dir/test_dir')
>>> for entry in os.scandir('/host_dir'):
...   if entry.name == 'test_dir':
...     break
... 
>>> print(entry, entry.inode(), os.stat(entry.path, follow_symlinks=False).st_ino)
<DirEntry 'test_dir'> 12873222 12873222
>>> assert entry.inode() == os.stat(entry.path, follow_symlinks=False).st_ino
>>> 

Similar issue - https://bugs.python.org/issue32811.

----------
components: Build
messages: 335275
nosy: decaz
priority: normal
severity: normal
status: open
title: os.DirEntry.inode() returns invalid value within Docker container
type: behavior
versions: Python 3.7

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue35974>
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