MIME-Version: 1.0
References: <d72505be-f19c-47dd-bd3f-b7a55f421ba6@cmatte.me>
In-Reply-To: <d72505be-f19c-47dd-bd3f-b7a55f421ba6@cmatte.me>
From: Magnus Hagander <magnus@hagander.net>
Date: Fri, 12 Jun 2026 12:25:19 +0200
Message-ID: 
 <CABUevEw5vaGmCz-O5dFqmfszXO_aQPC=ggWSVh9WUqdgc6NepQ@mail.gmail.com>
Subject: Re: [PATCH] pgarchives: Fix crash when receiving a request with an
 incorrect If-Modified-Since header
To: =?UTF-8?Q?C=C3=A9lestin_Matte?= <celestin.matte@cmatte.me>
Cc: PostgreSQL WWW <pgsql-www@lists.postgresql.org>
Content-Type: multipart/alternative; boundary="00000000000075aa7a06540be596"
Archived-At: 
 <https://www.postgresql.org/message-id/CABUevEw5vaGmCz-O5dFqmfszXO_aQPC%3DggWSVh9WUqdgc6NepQ%40mail.gmail.com>
Precedence: bulk

--00000000000075aa7a06540be596
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Fri, 12 Jun 2026 at 10:52, C=C3=A9lestin Matte <celestin.matte@cmatte.me=
>
wrote:

> Django crashes when receiving a request containing a If-Modified-Since
> header with an incorrect date:
>
>
> Traceback (most recent call last):
>     File
> "/path/lib/python3.13/site-packages/django/core/handlers/exception.py",
> line 55, in inner
>       response =3D get_response(request)
>                  ^^^^^^^^^^^^^^^^^^^^^
>     File
> "/path/lib/python3.13/site-packages/django/core/handlers/base.py", line
> 197, in _get_response
>       response =3D wrapped_callback(request, *callback_args,
> **callback_kwargs)
>
>  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>     File "/path/archives/mailarchives/views.py", line 112, in __cache
>       resp =3D fn(request, *_args, **_kwargs)
>              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>     File "/path/archives/mailarchives/views.py", line 500, in message
>       if ims >=3D newest:
>          ^^^^^^^^^^^^^
>
> Exception Type: TypeError at /message-id/<redacted>
> Exception Value: '>=3D' not supported between instances of 'NoneType' and
> 'int'
>
>
> This patch adds a condition to avoid this.
>

Good catch. Applied. Thanks!


>
> (For some reason, archives on postgresql.org do NOT crash on this. Are
> headers filtered before reaching pgarchives there? When deploying upstrea=
m
> version of pgarchives locally, I do have this crash)
>

IMS in particular is handled by the cache. So the brwoser does IMS <-> the
cache, and then varnish does it independently <-> backend. And Varnish will
always create the correct headers. And since headers from the client are
never passed through to the backend, it doesn't show up there.


--=20
 Magnus Hagander
 Me: https://www.hagander.net/ <http://www.hagander.net/>
 Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/>

--00000000000075aa7a06540be596
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div dir=3D"ltr"><br></div><br><div class=3D"gmail_quote g=
mail_quote_container"><div dir=3D"ltr" class=3D"gmail_attr">On Fri, 12 Jun =
2026 at 10:52, C=C3=A9lestin Matte &lt;<a href=3D"mailto:celestin.matte@cma=
tte.me">celestin.matte@cmatte.me</a>&gt; wrote:<br></div><blockquote class=
=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rg=
b(204,204,204);padding-left:1ex">Django crashes when receiving a request co=
ntaining a If-Modified-Since header with an incorrect date:<br>
<br>
<br>
Traceback (most recent call last):<br>
=C2=A0 =C2=A0 File &quot;/path/lib/python3.13/site-packages/django/core/han=
dlers/exception.py&quot;, line 55, in inner<br>
=C2=A0 =C2=A0 =C2=A0 response =3D get_response(request)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0^^^^^^^^^^^^^=
^^^^^^^^<br>
=C2=A0 =C2=A0 File &quot;/path/lib/python3.13/site-packages/django/core/han=
dlers/base.py&quot;, line 197, in _get_response<br>
=C2=A0 =C2=A0 =C2=A0 response =3D wrapped_callback(request, *callback_args,=
 **callback_kwargs)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0^^^^^^^^^^^^^=
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^<br>
=C2=A0 =C2=A0 File &quot;/path/archives/mailarchives/views.py&quot;, line 1=
12, in __cache<br>
=C2=A0 =C2=A0 =C2=A0 resp =3D fn(request, *_args, **_kwargs)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0^^^^^^^^^^^^^^^^^^^^^^^^^^^=
^^^<br>
=C2=A0 =C2=A0 File &quot;/path/archives/mailarchives/views.py&quot;, line 5=
00, in message<br>
=C2=A0 =C2=A0 =C2=A0 if ims &gt;=3D newest:<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0^^^^^^^^^^^^^<br>
<br>
Exception Type: TypeError at /message-id/&lt;redacted&gt;<br>
Exception Value: &#39;&gt;=3D&#39; not supported between instances of &#39;=
NoneType&#39; and &#39;int&#39;<br>
<br>
<br>
This patch adds a condition to avoid this.<br></blockquote><div><br></div><=
div>Good catch. Applied. Thanks!</div><div>=C2=A0</div><blockquote class=3D=
"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(2=
04,204,204);padding-left:1ex">
<br>
(For some reason, archives on <a href=3D"http://postgresql.org" rel=3D"nore=
ferrer" target=3D"_blank">postgresql.org</a> do NOT crash on this. Are head=
ers filtered before reaching pgarchives there? When deploying upstream vers=
ion of pgarchives locally, I do have this crash)<br></blockquote><div><br><=
/div><div>IMS in particular is handled by the cache. So the brwoser does IM=
S &lt;-&gt; the cache, and then varnish does it independently &lt;-&gt; bac=
kend. And Varnish will always create the correct headers. And since headers=
 from the client are never passed through to the backend, it doesn&#39;t sh=
ow up there.</div><div><br></div><div>=C2=A0</div></div><span class=3D"gmai=
l_signature_prefix">-- </span><br><div dir=3D"ltr" class=3D"gmail_signature=
"><div dir=3D"ltr"><div>=C2=A0Magnus Hagander<br>=C2=A0Me: <a href=3D"http:=
//www.hagander.net/" target=3D"_blank">https://www.hagander.net/</a><br>=C2=
=A0Work: <a href=3D"http://www.redpill-linpro.com/" target=3D"_blank">https=
://www.redpill-linpro.com/</a></div></div></div></div>

--00000000000075aa7a06540be596--