Webcams

[#1]

Hello, Im a software developer and we just got back bug reports from users telling us that there seems to be a problem with the QuickCam software. I downloaded the latest version of the installation:
(information tab in program properties for the installation file qc1150.exe)

Logitech QuickCam 11.5.0 Software (SVE)
Version 11.5.0.1169

Right after the installation of the QuickCam software, my program crashed.
Starting our program in winDbg gave me:

ModLoad: 010f0000 0110b000 C:\Program Files\Common Files\Logishrd\LVMVFM\LVPrcInj.dll
(17ac.1678): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=00000000 ebx=fffffffc ecx=00000000 edx=00000004 esi=00b53f80 edi=00b53f84
eip=77dbb15f esp=0024fbdc ebp=0024fc2c iopl=0 nv up ei pl nz ac po cy
cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010213
ntdll!RtlPcToFileHeader+0x2e6:

Problem confirmed on Windows XP SP2, and Windows Vista.

- What actions can I take to prevent LVPrcInj.dll to be injected?
- Is there anything I could add to handle the dll injection? (Like skype seems to do)
- Are there any known problems that could cause the dll injection to crash another program? What I understand from reading other posts on this subject, is that there are other programs like BitComet, POVRay etc. crashes to.

[#2]

Welcome to the Logitech Community Webcam Forum magu!

---

magu asks -

What actions can I take to prevent LVPrcInj.dll to be injected?

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The simplest way is to uninstall the Logitech supplied QuickCam software.



Thanks.


Edit - Fix typo.

Message Edited by KachiWachi on 03-08-2009 02:18 PM

[#3]

We are aiming on making the usage of our program as effortless as possible, and would like to resolve this issue instead. Can you provide me with any documents showing how logitech would like the attached dll to be handled?
If no such document exists, would it be possible to get in contact with one of the developers?

regards
Martin

[#4]

What you are asking is way out of scope for this forum.

If this is for a business related project, please contact Logitech as a Partner.

Thanks.

[#5]

While searching for a solution to a similar problem i came across this thread.

Currently a network i'm responsible for managing has about a dozen logitech webcams attached to various workstations (this client wanted a cheap video conferencing solution).

Unfortunately the latest roll out of Symantec EndPoint Protection FAILED on those machines because of the Logitech software sticking data into the Windows registry key "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\PendingFileRenameOperations"

Luckily deleting the registry value & data solved the problem. but this problem should have NEVER existed to begin with...

Logitech, Please re-think this implementation of your software.

[#6]

Welcome to the Logitech Community Webcam Forum drivetheory!


For the latest information concerning this issue, please see FAQ #8355.


Thanks.

[#7]

Hi,

I wanted to follow up on this, because there's another problem with LVPrcInj.dll -- it overrides the default C++ terminate and unexpected handlers.

That is, at some point LVPrcInj.dll calls std::set_terminate_handler(), which is called by the C++ runtime at points of unexpected execution.

This in and of itself is no big deal, but LVPrcInj.dll is loaded into every process started, and if one of those processes attempt to set their own terminate handler, it will be overridden by LVPrcInj, causing the program to behave differently from the way it was originally written. Logitech's degenerate implementation replaces whatever was specified beforehand.

I found this when I was debugging why std::terminate was called in my app, and I couldn't get my own handler to execute. It took me a couple of days to start suspecting LVPrcInj.dll, and sure enough, after uninstalling, everything worked as expected.

The FAQ entry makes it look like there are improvements to be made to the injected DLL, so here's to hoping you don't mess around with process-global state from your rogue module anymore.

- Kim

[#8]

Welcome to the Logitech Community Webcam Forum kimgr!


1) What is the 8xxxxx (or 860-xxxxxx) series number from the camera tag (FAQ #3427), or preferably... the USB\VID ID?

2) Which version of the Logitech supplied QuickCam software application/drivers is installed (FAQ #5105)?

3) What Operating System (OS) is installed?



Thanks.

[#9]

Hi KachiWachi,

Thanks.

I only temporarily had the LogiTech device attached to my machine for a remote presentation, so I don't know the answer to the first two questions.

I'm running Windows XP SP2.

- Kim

[#10]

That said, I'm not really looking for help, I'm just glad I got your software uninstalled, and I wanted to let you know the problems it caused me so you can look into improving future versions.

- Kim