Slashdot Mirror
Nvidia Blames Apple For Bug That Exposes Browsing In Chrome's Incognito (venturebeat.com)
An anonymous reader points out this story at VentureBeat about a bug in Chrome's incognito mode that might be a cause for concern for some Apple users. From the story: "If you use Google Chrome's incognito mode to hide what you browse (ahem, porn), this might pique your interest. University of Toronto engineering student Evan Andersen discovered a bug that affects Nvidia graphics cards, exposing content that you thought would be for your eyes only. And because this only happens on Macs, Nvidia is pointing the finger at Apple."
Chrome advertises its Incognito mode as leaving no traces behind. Therefore, it should be responsible for wiping its framebuffer, just as it clears caches, cookies and history. It's like writing a file shredder that doesn't actually overwrite files, then blaming the OS and hard drive manufacturer for the oversight.
It might be nice if framebuffers and such were zeroed on release, but like overwriting files, it's a time/energy/security tradeoff. Besides, the screen isn't really protected anyway; IIRC applications on most OSes can capture the screen without even admin privileges. After apps are sandboxed into seeing only their own windows we can talk about securing the framebuffer.
How can I believe you when you tell me what I don't want to hear?
It's not a 5% hit. You only have to clear the buffer once on exit. And, Nvidia is right:This is something the OS should do (just like it closes filehandles, and frees other resources on exit). Why not leave it up to the app? Because, apps don't always exit cleanly.
IOS saves screenshots of the applications for the task selector thingy and also for "fast" application switching where the screenshot is used for the zooming effect and as placeholder while the real application is still being (re)loaded. There is a separate screenshot for each orientation. It is possible that you launch or switch to the the browser or some other application and IOS will display a possibly very old screenshot of your private porn browsing session or some other private stuff that you had closed and purged from the logs ages ago. During the application switch effect the old screenshot is visible only momentarily but the same images can also be viewed from the task selector.
1. Device at orientation A: open browser, enter private mode and browse for some pron.
2. Switch to the home screen (screenshot it saved) and change to orientation B
3. Go back to browser and close all pron tabs
4. Switch to the home screen (screenshot is saved but this one is for orientation B)
5. Change back to orientation A and enter the task selector or go back to the application. The old private browsing screenshot should be visible.
There isn't a single OS that doesn't do this. You wrote a bunch of crap that has nothing to do with what the GP wrote.
The question is where the image is leaking from. It's either from the copy owned Chrome itself, or from the copy owned by the window server. Apple's window server keeps a copy of the frame buffer to allow the system to kill the underlying application (if it advertises support for sudden termination) and have it resurrect in the same state without the user being aware. This is part of the mechanism on Darwin for handling low-memory situations: an application that has no unsaved state is killed and is then restarted when the user attempts to interact with it. This copy of the window contents may last for longer than the attached application (I don't know what the policy is for garbage collecting them).
I am TheRaven on Soylent News