Exclusive page-frame ownership [LWN.net]

Exclusive page-frame ownership

Posted Sep 15, 2016 1:11 UTC (Thu) by spender (guest, #23067)
Parent article: Exclusive page-frame ownership

This patch is bogus -- it's a good example of a poor mitigation. If the root problem is W, and there are methods X, Y, and Z to exploit that problem, all equally feasible for an attacker, it's silly to promote patches like this as a solution to the problem when they can only deal with method X. It's faith-based security, but surely would be considered a KSPP success story if merged.

I should also mention that there are numerous glaring factual errors in the article (unsurprisingly due to repeating the same mistakes of the paper author and not adjusting some of the claims to kernels within the past 2 years or so) but I'm curious to see if anyone else can spot them without my help, or if everyone will just take the article at face value.

-Brad

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Posted Sep 15, 2016 6:35 UTC (Thu) by tao (subscriber, #17563) [Link] (9 responses)

While solution A to problem W that only solves X, not Y or Z is obviously less than ideal, it always trumps solution B which hasn't been submitted upstream (and thus, in practice, doesn't exist), no matter how superior it is.

Patch submissions, with follow-through, until the patch has been merged will always count for more than an out of tree patch that the author, and their fanclub, doesn't want to, or cannot be bothered to, go through the effort of getting merged.

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Posted Sep 15, 2016 8:56 UTC (Thu) by PaXTeam (guest, #24616) [Link] (3 responses)

> Patch submissions, with follow-through, until the patch has been merged will always count for more than an out of tree patch that the author,
> and their fanclub, doesn't want to, or cannot be bothered to, go through the effort of getting merged.

here's some reading material: https://lwn.net/Articles/700358/ tl;dr: you don't get to make demands on my free time and then blame me for not abiding by them.

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Posted Sep 15, 2016 17:55 UTC (Thu) by flussence (guest, #85566) [Link] (2 responses)

> you don't get to make demands on my free time and then blame me for not abiding by them.
That's exactly what you've been doing for years. You go a bit beyond lashing out at merely the upstream kernel hand that feeds you though; you also spew venom at reporters, developers and end users who don't shower you in praise and roses while also telling them you know what's best for them.

It's a shame you're *not* a paid slander-mercenary like rcweir, because at least then someone could pull the plug to spare us all from this whinging.

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Posted Sep 15, 2016 18:20 UTC (Thu) by PaXTeam (guest, #24616) [Link] (1 responses)

trolling works much better when you can actually present evidence but then again that's what trolls lack, don't they ;).

OK...

Posted Sep 15, 2016 18:22 UTC (Thu) by corbet (editor, #1) [Link]

I don't think this conversation is doing any good for anybody involved, bystanders included. Perhaps it's time for everybody to stop throwing mudballs and let it be, please?

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Posted Sep 15, 2016 11:08 UTC (Thu) by spender (guest, #23067) [Link] (4 responses)

What does my comment have anything to do with the tired ad hominem you've regurgitated here? We already reviewed this mitigation back when the paper was initially released, and there are good reasons why it's not present in grsecurity. I guess I'll avoid offering any free review or hints here in the future and leave it up to the upstream "experts".

-Brad

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Posted Sep 15, 2016 11:50 UTC (Thu) by pizza (subscriber, #46) [Link] (2 responses)

> I guess I'll avoid offering any free review or hints here in the future and leave it up to the upstream "experts".

In the immortal words of _The Critic_ -- "And nothing of value was lost."

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Posted Sep 15, 2016 12:08 UTC (Thu) by spender (guest, #23067) [Link] (1 responses)

You've summed up the entirety of your comments well. Have you ever contributed anything of technical value?

-Brad

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Posted Sep 15, 2016 13:40 UTC (Thu) by pizza (subscriber, #46) [Link]

> You've summed up the entirety of your comments well.

Perhaps, but I'm not claiming that my comments here are of any inherent value, nor am I threatening to deprive LWN readers the awesomeness of my "free review or hints".

> Have you ever contributed anything of technical value?

Why yes, I have:

Two chunks of Linux kernel code bear my name -- One wifi driver that I heavily cleaned up [ie rewrote large chunks of], mainlined and still maintain, and another that I originally wrote but someone else mainlined (after some rewriting).

(So yes, I have first-hand knowledge of just how much work mainlining something can be. Incidentally, the latter bears quite a few similarities to this situation -- Only I had the maturity to not complain about how those folks doing the work I was unwilling to do were somehow doing it all wrong. I even tossed some patches their way to help out)

I'm also a major contributor to Gutenprint, having written drivers for several dozen photo printers.

Beyond that, there's a long tail of mostly-minor contributions to various F/OSS projects. I try to give back whenever possible, and my track record shows that I play well with others.

Any more questions?

Exclusive page-frame ownership

Posted Sep 16, 2016 15:36 UTC (Fri) by jschrod (subscriber, #1646) [Link]

If you could stop mentioning all the time that you are not willing to offer something, that would be even better.

Thanks in advance.