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https://issues.apache.org/jira/browse/GUACAMOLE-1717?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Mike Jumper reassigned GUACAMOLE-1717:
--------------------------------------
Assignee: (was: Mike Jumper)
> Cursor Improperly Initialized when Connecting to Gnome Remote Desktop via RDP
> -----------------------------------------------------------------------------
>
> Key: GUACAMOLE-1717
> URL: https://issues.apache.org/jira/browse/GUACAMOLE-1717
> Project: Guacamole
> Issue Type: Bug
> Components: RDP
> Affects Versions: 1.4.0
> Reporter: Mike Powers
> Priority: Minor
> Fix For: 1.6.0, 1.5.2
>
> Attachments: image-2022-11-20-20-14-11-333.png
>
>
> When connecting to a [Gnome Remote
> Desktop|https://gitlab.gnome.org/GNOME/gnome-remote-desktop] RDP instance the
> mouse cursor is created but the image data is never copied into the cursor's
> pixel buffer resulting in a garbled bitmap containing uninitialized data:
> !image-2022-11-20-20-14-11-333.png|width=656,height=355!
> This appears to happen because of this [guard
> condition|https://github.com/apache/guacamole-server/blob/3ca6bb0a61715d17dc263e565e6ce0de7354606c/src/protocols/rdp/pointer.c#L50]
> in src/protocols/rdp/pointer.c (line 49):
> {code:java}
> if (pointer->andMaskData && pointer->xorMaskData) {code}
>
> It appears when Gnome Remote Desktop [initializes
> cursors|https://gitlab.gnome.org/GNOME/gnome-remote-desktop/-/blob/master/src/grd-session-rdp.c#L591]
> when starting the session it sets `andMaskData` to NULL with a length of
> zero:
> {code:java}
> pointer_color->lengthAndMask = 0;
> pointer_color->lengthXorMask = xor_mask_length;
> pointer_color->andMaskData = NULL; {code}
> This causes the guard condition in the RDP plugin to fail to copy bitmap data
> from the server. It appears as if FreeRDP [correctly
> handles|https://github.com/FreeRDP/FreeRDP/blob/master/libfreerdp/codec/color.c#L430]
> the image data in {{freerdp_image_copy_from_pointer_data()}} if
> {{lengthAndMask}} == 0:
> {code:java}
> if (andMask)
> {
> if (andStep * nHeight > andMaskLength)
> return FALSE;
> }{code}
> I believe this guard condition is probably not necessary; removing it
> resolves the issue for me. I tested against both Gnome Remote Desktop and a
> Windows 11 Professional instance.
> Please let me know if you'd like any additional information or testing done.
> This was tested with Guacamole 1.4.0 from Docker Hub
> (guacamole/guacamole:1.4.0 and guacamole/guacd:1.4.0). Testing against a
> fresh install of Fedora 37/Gnome 43.
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