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Buffer Overflow Protection

Posted: Tue Sep 16, 2008 2:58 pm
by Calstvns
Hi all,

I did a search and did not see this discussed elsewhere. When working with my files using Windows Explorer, I open up a very heavy working folder for an HD project. As the computer begins to "read" the contents of the folder I have opened, a few seconds later my McAfee protection program will put up a message "buffer overflow protection" and shut down the explorer program.

This does not affect my ability to work in Video Studio. The only time it happens is when I try to explore my file folders. I am careful to have other buffer drains disconnected, such as having my camera off.

I can change McAfee to no longer protect me in this way, and of course the protection software is giving me dire warnings about allowing my buffer to overflow. McAfee says that buffer overflow can corrupt other data or make applications fail. But turning off the warning is the only way I can access any folder that has a lot of my work in it.

I realize I can make smaller workfolders. But my question for the board is whether "buffer overflow" is an issue at all, or if it's a bit of exaggerated concern by McAfee. What say you? Would you counsel that I keep buffer overflow protection turned off so I can explore my file folders?

Data: Using Corel Video Studio 12 / Computer: Processor Intel core 2 Quad 2.4 GHz, 1066 MHz, 8MB cache, memory 4096 MB 667MHz dual channel DDR2 SDRAM (4-1024MB modules), 500GB HD w/ 16 MB cache. Operating System--Vista

Posted: Tue Sep 16, 2008 6:08 pm
by DVDDoug
I realize I can make smaller workfolders. But my question for the board is whether "buffer overflow" is an issue at all, or if it's a bit of exaggerated concern by McAfee. What say you? Would you counsel that I keep buffer overflow protection turned off so I can explore my file folders?

As I understand it...

Buffer overflow is one technique used by virus writers. But when overflow happens, it's usually not a virus. It's usually a bug that might cause a crash, or some unpredictable behavior.

I don't know if you really have an overflow, or if McAfee is confused...

A properly written application should check the size/amount of data before it overflows a buffer. If the application itself gives you a "buffer overflow" error, it probably means that you've attempted to over-fill the buffer, the program hasn't allowed it, but you may have lost some data.

The virus works like this...

- The good (non-virus) program (or driver) reserves some memory as a buffer (temporary storage) for user-data, such as text, image, audio/video, etc.

- Let's say memory addresses 0 - 1000 are reserved for the buffer, and let's say addresses above 1000 store the "EXE" code for your program (or for another program).

- A virus writer can supply a chunk of data that's too big for the buffer. This "data" goes beyond the reserved memory area and overwrites the program in memory with malicious code. Then, when you think you're running a good program, you're actually running the virus.

Posted: Tue Sep 16, 2008 9:44 pm
by Ken Berry
Just how big is the folder in question? I regularly access folders containing up to around 50 or 60 GB of captured video on my own Quad, and never have any buffer overflow problems. But then again, I don't use McAfee!! :wink: :lol:

Posted: Wed Sep 17, 2008 4:06 pm
by Calstvns
Not as big as that, maybe 15 GB. Vista seems to look at all the files when you open a folder--a green bar progressively moves across the top of the vista window while the computer examines the files in some way. During this time, if my folder view is icons, each icon changes to a thumbnail of the video. But it doesn't matter whether it's in icon view or in regular detail view, during this process McAfee stops the process and shuts down the window, putting up a notice that my buffer was overflowing and that this is bad.

I can turn off the protection in McAfee, but I'm not sure whether that's a good idea or not. Isn't there a way to increase my buffer in my computer?

Posted: Wed Sep 17, 2008 5:21 pm
by Black Lab
I can turn off the protection in McAfee, but I'm not sure whether that's a good idea or not.
And this is one of the reasons why it is recommended to turn off virus protection, disable Internet, etc. when video editing.

Please read Creating a Video Editing Profile

Posted: Wed Sep 17, 2008 10:54 pm
by Ken Berry
The problem is, though, Jeff, that you can't create a profile in Vista... :cry:

Calstvns -- I have had that happen once -- not with McAfee, but getting that green bar and it gets to a certain point almost at the very end, but stops dead. In that situation I dound that the usually pretty indestructible Windows Explorer in Vista would hang and re-start. I eventually put 2 + 2 together, and worked out that that folder contained a video that I had had difficulty getting to open in VS for whatever reason.

It has happened a couple of times with high definition .tp files captured on my DVico fusion HDTV card and converted, suprisingly enough, with Womble to HDV/mpeg-2... VS would eventually -- after at least 5 minutes -- 'see' the file when I tried to insert it. But after that, when I would try to edit it in any way, I would get the same delay. Anyway, eventually, I deleted that file from VS, using the Shift button at the same time to remove it from the computer altogether, and after that, I could once again open that folder in Windows Explorer with no problem...

Anyway, you might need to think whether there was anything peculiar about one or more of the videos in that folder... But I am afraid, after that, it's all a matter of trial and error... :cry:

Posted: Thu Sep 18, 2008 2:39 am
by Black Lab
Sorry, I thought Steve had a work-around.