Raspbian stretch ships with an OpenHMD package, but vrzero's bindings buffer overflow

[vitorio]

Using a DK1 with an RPi3 with Raspbian Lite (no X11) stretch, I see there's a stock libopenhmd package available, libopenhmd0 (0.2.0-3), several versions newer than the one packaged here.

To try and get vrzero's hmd.py to use it, I have to change libopenhmd.so to libopenhmd.so.0 in hmd.py, however, this results in a buffer overflow.

$ python abbey.py 
shader(2) barrel, Compiled
shader(3) barrel, Compiled
('keyboards =', [(0, 0), (1, 1)])
('mice = ', [])
('joysticks =', [])
*** buffer overflow detected ***: python terminated
Aborted

Removing the stock libopenhmd and installing the vrzero-packaged one works.

[WayneKeenan]

I'm finding that on a RPi 3+ on 2018-03-13-raspbian-stretch which is still libopenhmd0 (0.2.0-3):

• this doesn't happen without a Rift attached.
• occurs with a DK 2 attached
• occurs using an alternative Python binding to the library (A Cython based module)

I've taken a fork of the other library and had to make a minor tweak to disable a BUTTON feature not present in the libopenhmd0 package in the Stretch repo (not that this should matter at all).
That fork is https://github.com/WayneKeenan/python-rift.git

All very interesting, will look at fixing it.

[WayneKeenan]

I've just built OpenHMD from source (0.3.0) and it doesn't crash.
Therefore I'm just going to provide the latest build as a .deb rather than spend time debugging why the Debian 0.2.0 package crashes.

If you'd like to raise the issue with upstream that would be good, thanks.

[WayneKeenan]

Whilst getting VR Zero to work with the Sony PSVR I've found the OpenHMD API 3.0 would work with the Rift but not the PSVR. HMD Device selection is more complicated with the PSVR (5 devices presented) than the Rift (1 device presented). So I made some changed to my Python hmd.py wrapper...

The updated hmd.py in the SonyPSVR branch is working with the PSVR (I need to retest Rift).

I reverted to the OpenHMD 2.0 debian package and although it no longer crashes with a buffer overflow, the sensor readings appear to be the 'dummy' default OpenHMD device.

So, progress of sorts and perhaps this can be fixed for the Debian version, I will investigate further.

[WayneKeenan]

I can confirm that this is fixed in the PSVR branch, the Rift sensor readings are being received using the stock Debian libopenhmd0 package,

However, it turns out there is no PSVR driver in OpenHMD 2.0 so the next release of VRZero will (optionally) need the OpenHMD 3.0 deb (I'm including in the repo(, if someone wants to use the PSVR, but obviously not if they have a Rift.

I'll leave this open until things have settled after the current PSVR experimental branch.

[WayneKeenan]

closing this as stale and plan to fix on latest Pi4 & Pi OS