[Django] #29800: Django hangs when Content-Length hangs

[Django]

#29800: Django hangs when Content-Length hangs
-----------------------------------------+------------------------
Reporter: monester | Owner: nobody
Type: Bug | Status: new
Component: Uncategorized | Version: 2.1
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 |
-----------------------------------------+------------------------
When sending incorrect content-length header to application, django hangs
on reading request.body.

Steps to reproduce:

curl -v -X POST -H "Accept: */*" -H "Content-Length: 22" -d "1"
http://127.0.0.1:8000

with following handler:
{{{#!python
def index(request):
return HttpResponse(content=request.body)
}}}

--
Ticket URL: <https://code.djangoproject.com/ticket/29800>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------+--------------------------------------

Reporter: monester | Owner: nobody
Type: Bug | Status: new
Component: Uncategorized | Version: 2.1

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

-------------------------------+--------------------------------------

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:1>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------+------------------------------------

Reporter: monester | Owner: nobody
Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------+------------------------------------
Changes (by Tim Graham):

* component: Uncategorized => HTTP handling
* stage: Unreviewed => Accepted

Comment:

I can reproduce this, although I had to add `@csrf_exempt` to the view to
bypass the CSRF error page.

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:2>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------+------------------------------------

Reporter: monester | Owner: nobody
Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------+------------------------------------
Changes (by Herbert Fortes):

* cc: Herbert Fortes (added)

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:3>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------
Reporter: Alexander Charykov | Owner:
| patriksletmo
Type: Bug | Status: assigned

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------------+-------------------------------------
Changes (by patriksletmo):

* owner: nobody => patriksletmo
* status: new => assigned

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:4>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------
Reporter: Alexander Charykov | Owner:
| patriksletmo
Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------------+-------------------------------------

Comment (by Tim Graham):

The security team discussed this issue to confirm that we shouldn't treat
it as a security issue.

From Markus Holtermann:

The issue can also be reproduced with:

$ gunicorn foo.wsgi --access-logfile - --worker-connections 5

From Simon Charette:

I cannot reproduce when Django is behind a reverse proxy such as NGINX
with proxy_request_buffering on which is the default.

Given the development server should never be used in production and
gunicorn documentation strongly recommends to use it behind a proxy server
this doesn't sound severe to me. We should add a timeout on body read to
the development server but it's unlikely to be an attack vector if you
already follow best practice.

I mean, both Django's development server and gunicorn have been known to
be vulnerable to slow loris attacks and friends for a while at this point
at it feels to me that serving Django apps behind a reverse proxy is the
norm nowadays.

From Collin Anderson:

I this has come up before (or maybe it's a related issue):
https://groups.google.com/d/topic/django-developers/bYzHczKNoqM/discussion

From Claude Paroz:

Might be worth reaching to Graham Dumpleton about this issue. The WSGI
specs talk about a CONTENT_LENGTH shorter than the payload, but I'm not
sure it addresses the reverse issue.

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:5>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------

Reporter: Alexander Charykov | Owner: Patrik
| Sletmo

Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------------+-------------------------------------

Comment (by Patrik Sletmo):

I skimmed through the WSGI specification and it contains a description on
how to handle Content-Length headers shorter than the payload, but as
Claude Paroz guessed it does not give any instructions for handling the
opposite case.

As the recommended way of running Django in production is behind a reverse
proxy I don't think that there should be any fix implemented that attempts
to mitigate the effect of a Slowloris attack. I do however think that from
a usability standpoint it could make sense not to hang the entire
application in case the request given above is received.

Would there be any practical implications that could motivate against
using a timeout period for receiving the data? If nginx is used as a
reverse proxy with the default option proxy_request_buffering set, the
timeout would limit the time required for transmitting the request from
the reverese proxy to Django, and this really shouldn't take any
substantial amount of time. I suppose that implementing a timeout option
in Django in some situations could create the need to configure a timeout
in both the reverse proxy and in Django, but I think that these cases are
rather slim.

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:6>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------
Reporter: Alexander Charykov | Owner: Patrik
| Sletmo
Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------------+-------------------------------------

Comment (by Patrik Sletmo):

I've been thinking some more on how to handle this issue and right now I'm
considering the possibility of not fixing it at all. The two alternatives
would in that case be the following:

1. Mark the issue as "wontfix".
or
2. Document the issue so that users are aware of its existence, and refer
to the use of a reverse proxy. My suggestion is that it could be added
here somehow https://docs.djangoproject.com/en/2.1/topics/security
/#additional-security-topics.

The reasoning behind not providing any fix beyond what has been suggested
above is simple. The types of HTTP requests triggering the hang are
typically only crafted by a malicious party with the intention to trigger
this sort of bug. I can not imagine any case in which the behaviour
documented in this issue would come as a surprise to anyone performing
this request on their development server. As this bug is nearly never
triggered unintentionally when developing, and also protected against when
deployed properly in production, I think that it seems strange to
introduce additional functionality that must be maintained. I would say
that an introduced timeout comes with more complications than it solves.

Do you have any opinion on the above mentioned proposals, Alexander
Charykov and Tim Graham?

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:7>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)
Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Changes (by Patrik Sletmo):

* owner: Patrik Sletmo => (none)
* status: assigned => new

Comment:

Since I lack the required insight in the Django project and thus cannot
decide on what solution would be the best one on my own, I've chosen to
deassign myself from this issue. I hope that my reasoning above may become
useful in the future.

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:8>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------

Comment (by Jannik Schürg):

I think this is what it boils down to:

{{{#!python
from wsgiref.simple_server import make_server

def app(environ, start_response):
# does not timeout for malformd 'Content-Length'
environ['wsgi.input'].read()

make_server('', 8000, app).serve_forever()
}}}

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:9>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------

Comment (by Zach Garwood):

Replying to [comment:7 Patrik Sletmo]:

> 2. Document the issue so that users are aware of its existence, and
refer to the use of a reverse proxy. My suggestion is that it could be
added here somehow https://docs.djangoproject.com/en/2.1/topics/security
/#additional-security-topics.

I think this is the best course of action.

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:10>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------

Old description:

> When sending incorrect content-length header to application, django hangs
> on reading request.body.
>
> Steps to reproduce:
>
> curl -v -X POST -H "Accept: */*" -H "Content-Length: 22" -d "1"
> http://127.0.0.1:8000
>
> with following handler:
> {{{#!python
> def index(request):
> return HttpResponse(content=request.body)
> }}}

New description:

When sending incorrect content-length header to application, django hangs
on reading request.body.

Steps to reproduce:

curl -v -X POST -H "Accept: */*" -H "Content-Length: 22" -d "1"
http://127.0.0.1:8000

with following handler:
{{{#!python
from django.http import HttpResponse
from django.views.decorators.csrf import csrf_exempt

@csrf_exempt
def index(request):
return HttpResponse(content=request.body)
}}}

--

Comment (by Manan):

Added a csrf_exempt to bypass the default 403 CSRF error page

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:11>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Changes (by Sam Kuffer):

* Attachment "doc_update.diff" added.

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Changes (by Sam Kuffer):

* cc: Sam Kuffer (added)

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:12>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------

Comment (by Adam Zapletal):

I confirmed that this is still an issue and would be happy to open a pull
request with the proposed docs patch above if there's interest in it.

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:13>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Changes (by Mariusz Felisiak):

* cc: Natalia Bidart (added)

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:14>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------

Comment (by thenomadlad):

Hi folks, I encountered a similar bug and since this thread was the only
place I could see information on this bug I thought I'll share what I
found after working around this issue

TL;DR I think this is because of the way gunicorn uses the content-length
header
[here](https://github.com/benoitc/gunicorn/blob/ab9c8301cb9ae573ba597154ddeea16f0326fc15/gunicorn/http/body.py#L128-L129)

My service is a flask+gunicorn service in a kubernetes cluster. we have
distributed tracing enabled at the flask layer and when I include a
content-length header, I saw traces start and end at the load-balancer
layer with a 400 status code after a 1s timeout, but no traces start for
the flask application. Between the load-balancer and my flask app, I had a
few places to look - the k8s-networking, docker-runtime, python 3.10 and
gunicorn. Naturally my biggest suspect was gunicorn

Gunicorn chooses different "readers" based on whether a `content-length`
header is set, the `transfer-encoding` header has value `chunked`, or
neither:
https://github.com/benoitc/gunicorn/blob/ab9c8301cb9ae573ba597154ddeea16f0326fc15/gunicorn/http/message.py#L125-L154

if content-length is set, it uses a `LengthReader` is used, which loops
infinitely until a certain length is reached:
https://github.com/benoitc/gunicorn/blob/ab9c8301cb9ae573ba597154ddeea16f0326fc15/gunicorn/http/body.py#L126-L130

This is a feature of gunicorn, I think it relies on timing out when the
reader doesn't have enough bytes

> I cannot reproduce when Django is behind a reverse proxy such as NGINX
with proxy_request_buffering on which is the default.

I believe this might be happening because proxy_request_buffering adds a
correct content-length header after buffering the request on the nginx
side? not sure I have the tools to verify this tbh so I would appreciate
it if someone can confirm this

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:15>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Comment (by mag123c):

Is this still open?
--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:16>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Comment (by Lakshya Prasad):

Hi, I’d like to work on this ticket. I’ll investigate the issue and submit
a patch if no one else is currently working on it.

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:16>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Comment (by Lakshya Prasad):

After investigating, it seems the hang occurs because Django relies on the
WSGI input stream (e.g., wsgiref or gunicorn), which blocks until the
declared Content-Length is fully read.

Since the WSGI spec does not define behavior for Content-Length larger
than actual payload, and production setups typically rely on reverse
proxies (e.g., nginx) to validate requests, this might not be appropriate
to fix at Django level.

I’d like to propose adding documentation explaining this behavior and
recommending use of a reverse proxy or proper request validation.
--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:17>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------

Reporter: Alexander Charykov | Owner: Lakshya
| Prasad
Type: Bug | Status: assigned

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------------+-------------------------------------
Changes (by Lakshya Prasad):

* owner: (none) => Lakshya Prasad

* status: new => assigned

Comment:

Assigning this ticket to myself. I’ve started investigating the issue and
will propose a solution shortly.
--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:18>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------
Reporter: Alexander Charykov | Owner: Lakshya
| Prasad
Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

-------------------------------------+-------------------------------------
Comment (by Lakshya Prasad):

After investigating further, I was able to reproduce the issue where
Django appears to hang when a request is sent with a Content-Length header
larger than the actual payload.

Tracing the code path shows that `request.body` ultimately calls
`environ['wsgi.input'].read()`, which blocks until the number of bytes
specified by Content-Length is fully read. Since fewer bytes are actually
sent, the read operation does not complete, causing the request to hang.

This behavior seems to originate from the WSGI layer (e.g., `wsgiref` or
`gunicorn`) rather than Django itself. Additionally, the WSGI
specification does not define how to handle cases where Content-Length
exceeds the actual payload.

Given that Django is typically deployed behind a reverse proxy (such as
nginx), which buffers and validates request bodies, this issue is unlikely
to impact production environments.

Based on this, I’d like to propose documenting this behavior rather than
attempting to modify Django’s request handling. I can work on a
documentation patch if this approach is acceptable.
--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:19>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------
Reporter: Alexander Charykov | Owner: Lakshya
| Prasad
Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
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 Lakshya Prasad):

* has_patch: 0 => 1

Comment:

https://github.com/django/django/pull/20967
--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:20>

[Django]

#29800: Django hangs when Content-Length has incorrect value
-------------------------------------+-------------------------------------
Reporter: Alexander Charykov | Owner: Lakshya
| Prasad
Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
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 Lakshya Prasad):

Updated PR with a clean branch containing only the documentation changes.

PR: https://github.com/django/django/pull/20972
--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:21>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: (none)

Type: Bug | Status: new

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Changes (by Jacob Walls):

* has_patch: 1 => 0
* owner: Lakshya Prasad => (none)

* status: assigned => new

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:22>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------

Reporter: Alexander Charykov | Owner: Prithvi
Type: Bug | Status: assigned

Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted

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

------------------------------------+------------------------------------
Changes (by Prithvi):

* owner: (none) => Prithvi

* status: new => assigned

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:23>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: Prithvi
Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
------------------------------------+------------------------------------

Description changed by Prithvi:

Old description:

> When sending incorrect content-length header to application, django hangs
> on reading request.body.
>
> Steps to reproduce:
>
> curl -v -X POST -H "Accept: */*" -H "Content-Length: 22" -d "1"
> http://127.0.0.1:8000
>
> with following handler:
> {{{#!python

> from django.http import HttpResponse
> from django.views.decorators.csrf import csrf_exempt
>
> @csrf_exempt
> def index(request):
> return HttpResponse(content=request.body)
> }}}

New description:

When sending incorrect content-length header to application, django hangs
on reading request.body.

Steps to reproduce:

{{{#!bash

curl -v -X POST -H "Accept: */*" -H "Content-Length: 22" -d "1"
http://127.0.0.1:8000
}}}

with following handler:
{{{#!python
from django.http import HttpResponse
from django.views.decorators.csrf import csrf_exempt

@csrf_exempt
def index(request):
return HttpResponse(content=request.body)
}}}

--

--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:24>

[Django]

#29800: Django hangs when Content-Length has incorrect value
------------------------------------+------------------------------------
Reporter: Alexander Charykov | Owner: Prithvi
Type: Bug | Status: assigned
Component: HTTP handling | Version: 2.1
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
------------------------------------+------------------------------------

Comment (by Prithvi):

Hello,

I was able to reproduce with the development server. I understand that
this won't be an issue in production environments where the application
resides behind a real proxy and server however the dev server does not
send back any response to the caller.

What should be the expected behavior in the development server as no
response returned does not seem like a good behaviour for the dev server?

Prithvi
--
Ticket URL: <https://code.djangoproject.com/ticket/29800#comment:25>