X2Go Bug report logs - #900
Gedit, gnome-terminal and others crash in rootless mode

Package: libnx-x11; Maintainer for libnx-x11 is X2Go Developers <x2go-dev@lists.x2go.org>; Source for libnx-x11 is src:nx-libs.

Reported by: Camilo Alejandro Arboleda <camilo@ieee.org>

Date: Thu, 2 Jul 2015 06:25:02 UTC

Severity: normal

Tags: patch

Merged with 878, 956

Forwarded to https://github.com/ArcticaProject/nx-libs/issues/82

Full log

Message #13 received at 900@bugs.x2go.org (full text, mbox, reply):

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From: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>
To: Camilo Alejandro Arboleda <camilo@ieee.org>, 900@bugs.x2go.org
Subject: Re: [X2Go-Dev] Bug#900: Gedit, gnome-terminal and others crash in
 rootless mode
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Control: tags -1 patch
Control: forwarded -1 https://github.com/ArcticaProject/nx-libs/issues/82

Hi Camilo,

On  Do 02 Jul 2015 08:21:22 CEST, Camilo Alejandro Arboleda wrote:

Your bug report has just been moved [1] to the new upstream location  
of nx-libs on Github.

> Looking at the highlighted values, it seems that gedit is sending a
> malformed ChangeProperty request, and rootless is failing to process it.

Is it really a malformed request or a problem with broken BIG-REQUESTS  
support [2] in libXcomp3 (aka nxcomp)?

> Specifically the segment between lines 735-780, tries to set a property
> that is bigger than the maximum size required, but because it's a
> malformed request it ends up writing in memory outside the boundaries of
> the output buffer.
> Alternatives:
>  1. Ensure that nxagentExportProperty never writes beyond the boundaries
>     of the output buffer.
>  2. Resize the output buffer to match the required size
>     (ProcChangeProperty seems to do something similar).
>  3. Ignore big requests (see attached patch).

Is option 3. really the optimal approach? It feels like option 2.  
would be the way to go here...

Please continue, if possible for you, this discussion on Github.


[1] https://github.com/ArcticaProject/nx-libs/issues/82
[2] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=766299

mike gabriel, herweg 7, 24357 fleckeby
fon: +49 (1520) 1976 148

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mail: mike.gabriel@das-netzwerkteam.de, http://das-netzwerkteam.de

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