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Traditional C "Hello World" working in NaCl

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Re: Traditional C "Hello World" working in NaCl

#4

I wonder how it handles a bogus printf format string.

The same way the underlying printf implementation does? This isn't wrapping printf(3), just the underlying write(2).

Are you trying to ask if it catches, e.g., format string vulnerabilities? I think the answer to that is: Native Client's aim is to be a safe x86 VM, so — hopefully. But to me personally, it seems unlikely that they've thought of everything.

Re: Traditional C "Hello World" working in NaCl

#7

As a side note, why is it that I have to sign in to Google in order to be able to see this? Is registration /really/ necessary for Google Groups?

You are right. It's very annoying. It's even worse than having links that are behind a paywall, because at least a paywall usually indicates that funds are flowing to the person (reporter, etc.) who created the content. The google groups situation is quite different, and quite annoying. I never login to google groups to see something listed on HN. I wonder whether HN could provide an option to let readers avoid such items, by removing them from the listing or flagging them?

Re: Traditional C "Hello World" working in NaCl

#8
post #4

I wonder how it handles a bogus printf format string.

The same way the underlying printf implementation does? This isn't wrapping printf(3), just the underlying write(2). Are you trying to ask if it catches, e.g., format string vulnerabilities? I think the answer to that is: Native Client's aim is to be a safe x86 VM, so — hopefully. But to me personally, it seems unlikely that they've thought of everything.

The important part of the design - the bit that makes it achievable - is that it's not a general x86 VM. It only accepts a limited subset of valid x86 object code, a subset chosen to make validation a tractable problem. This requires a modified compiler be used.

The unlikelihood that the original design was perfect is probably why they had the "Native Client Security Contest" a few years ago - and indeed independent researchers found several flaws. Personally, I'm a lot happier with it now that they've fixed everything that Mark Dowd could find wrong with it ;)

Re: Traditional C "Hello World" working in NaCl

#9

As a side note, why is it that I have to sign in to Google in order to be able to see this? Is registration /really/ necessary for Google Groups?

It works fine here (Chrome on Windows) even if I log out.

I think it's a bug. Are you on a mobile browser?

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