[Django] #37081: loaddata fails when a directory in the fixture path contains a dot

[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------
Reporter: Alisson Silveira | Type: Bug
Status: new | Component: Core
| (Management commands)
Version: 6.0 | Severity: Normal
Keywords: | Triage Stage:
| Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
How to reproduce:

Create a fixture in a directory containing a dot, for example:
{{{
fixtures/fix.v1/data.json
}}}

Run (without specifying the file extension):
{{{
python manage.py loaddata fixtures/fix.v1/data
}}}

This raises:
{{{
CommandError: Problem installing fixture 'fixtures/fix': v1/data is not a
known serialization format.
}}}

This occurs when a directory in the fixture path contains a dot, as the
full path is incorrectly split on "." instead of operating on the file
name.

Expected behavior: Django should correctly determine the fixture format
based on the file name and load the fixture successfully, ignoring dots in
directory names.

A fix has been identified and will be submitted in a pull request.
--
Ticket URL: <https://code.djangoproject.com/ticket/37081>
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[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------

Reporter: Alisson Silveira | Owner: Alisson
| Silveira
Type: Bug | Status: assigned
Component: Core (Management | Version: 6.0
commands) |
Severity: Normal | Resolution:

Keywords: | Triage Stage:
| Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by Alisson Silveira):

* owner: (none) => Alisson Silveira
* status: new => assigned

--
Ticket URL: <https://code.djangoproject.com/ticket/37081#comment:1>

[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------
Reporter: Alisson Silveira | Owner: Alisson
| Silveira
Type: Bug | Status: assigned
Component: Core (Management | Version: 6.0
commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage:
| Unreviewed

Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Changes (by Alisson Silveira):

* has_patch: 0 => 1

Comment:

Pull request: https://github.com/django/django/pull/21213
--
Ticket URL: <https://code.djangoproject.com/ticket/37081#comment:2>

[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------
Reporter: Alisson Silveira | Owner: Alisson
| Silveira
Type: Bug | Status: assigned
Component: Core (Management | Version: 6.0
commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage:
| Unreviewed
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Gert Burger):

Tested this on stable/6.0.x and 5.2.11, as reported, if the fixture
extension is not specified then any other dot in the path will incorrectly
be considered the separator for the extension.
--
Ticket URL: <https://code.djangoproject.com/ticket/37081#comment:3>

[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------
Reporter: Alisson Silveira | Owner: Alisson
| Silveira
Type: Bug | Status: assigned
Component: Core (Management | Version: 6.0
commands) |
Severity: Normal | Resolution:

Keywords: | Triage Stage: Accepted

Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by Sarah Boyce):

* stage: Unreviewed => Accepted

Comment:

Thank you! I think this is a bug worth addressing.
My only concern was whether this could create any path traversal issues
allowing something like `fixtures/../secret.json` but I think this would
be out of the scope of security issues anyway. See
https://docs.djangoproject.com/en/6.0/internals/security/#how-does-django-
evaluate-a-report
--
Ticket URL: <https://code.djangoproject.com/ticket/37081#comment:4>

[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------
Reporter: Alisson Silveira | Owner: Alisson
| Silveira
Type: Bug | Status: assigned

Component: Core (Management | Version: dev

commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Changes (by Sarah Boyce):

* version: 6.0 => dev

--
Ticket URL: <https://code.djangoproject.com/ticket/37081#comment:5>

[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------
Reporter: Alisson Silveira | Owner: Alisson
| Silveira
Type: Bug | Status: assigned
Component: Core (Management | Version: dev
commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Alisson Silveira):

Replying to [comment:4 Sarah Boyce]:

> Thank you! I think this is a bug worth addressing.
> My only concern was whether this could create any path traversal issues
allowing something like `fixtures/../secret.json` but I think this would
be out of the scope of security issues anyway. See
https://docs.djangoproject.com/en/6.0/internals/security/#how-does-django-
evaluate-a-report

Thanks for your feedback, Sarah! I can provide a bit more context for the
record.

I decided to use a PurePath object to prevent any filesystem access, since
this method only needs to parse the filename. The filename is the only
piece of information being extracted and modified from the filepath. In
contrast, the current approach relies on rsplit() directly on the file
path string, which could potentially introduce security issues if the path
is manipulated. Using PurePath makes the intent clearer and provides safer
path handling.

Since this was a bug I encountered in a production system, my fix is
specifically focused on addressing that issue. However, I’d be more than
happy to address any additional fixes or improvements related to this area
if needed. Please let me know if you’d like me to explore any further
improvements here.
--
Ticket URL: <https://code.djangoproject.com/ticket/37081#comment:6>

[Django]

#37081: loaddata fails when a directory in the fixture path contains a dot
-------------------------------------+-------------------------------------
Reporter: Alisson Silveira | Owner: Alisson
| Silveira
Type: Bug | Status: assigned
Component: Core (Management | Version: dev
commands) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Raffaella):

Replying to [comment:4 Sarah Boyce]:
> Thank you! I think this is a bug worth addressing.
> My only concern was whether this could create any path traversal issues
allowing something like `fixtures/../secret.json` but I think this would
be out of the scope of security issues anyway. See
https://docs.djangoproject.com/en/6.0/internals/security/#how-does-django-
evaluate-a-report

Thank you Sarah for addressing this. I was following your suggestion and I
wrote this test:

{{{#!python
from django.core.management.commands.loaddata import Command
from django.core import serializers
from django.test import SimpleTestCase

class ParseNameTests(SimpleTestCase):
def setUp(self):
self.command = Command()
self.command.serialization_formats =
serializers.get_public_serializer_formats()

def test_parent_traversal_no_longer_raises(self):
name, ser_fmt, cmp_fmt = self.command.parse_name("../secret")
self.assertEqual(name, "../secret")
self.assertIsNone(ser_fmt)
self.assertIsNone(cmp_fmt)

}}}

This test passes with the `PurePath` fix. Without it,
`parse_name("../secret")` used to raise `CommandError` but only by
accident: the dots in `".."` get treated as format delimiters, triggering
the same "unknown serialization format" error this ticket is about but for
a different reason.
Note that a fixture name with an explicit extension, e.g.
`"../secret.json"`, is already parsed correctly even without this fix.
Even though this isn't a blocker, I think it's worth highlighting.
--
Ticket URL: <https://code.djangoproject.com/ticket/37081#comment:7>