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Google and Microsoft Disclose New CPU Flaw, and the Fix Can Slow Machines Down (theverge.com)

Posted by BeauHD on from the screeching-halt dept.

An anonymous reader quotes a report from The Verge: Microsoft and Google are jointly disclosing a new CPU security vulnerability that's similar to the Meltdown and Spectre flaws that were revealed earlier this year. Labelled Speculative Store Bypass (variant 4), the latest vulnerability is a similar exploit to Spectre and exploits speculative execution that modern CPUs use. Browsers like Safari, Edge, and Chrome were all patched for Meltdown earlier this year, and Intel says "these mitigations are also applicable to variant 4 and available for consumers to use today." However, unlike Meltdown (and more similar to Spectre) this new vulnerability will also include firmware updates for CPUs that could affect performance. Intel has already delivered microcode updates for Speculative Store Bypass in beta form to OEMs, and the company expects them to be more broadly available in the coming weeks. The firmware updates will set the Speculative Store Bypass protection to off-by-default, ensuring that most people won't see negative performance impacts.

"If enabled, we've observed a performance impact of approximately 2-8 percent based on overall scores for benchmarks like SYSmark 2014 SE and SPEC integer rate on client 1 and server 2 test systems," explains Leslie Culbertson, Intel's security chief. As a result, end users (and particularly system administrators) will have to pick between security or optimal performance. The choice, like previous variants of Spectre, will come down to individual systems and servers, and the fact that this new variant appears to be less of a risk than the CPU flaws that were discovered earlier this year.

17 of 83 comments (clear)

  1. Perverse way to drive future CPU upgrades by JoeyRox · · Score: 5, Interesting

    Or perhaps that's just the skeptic in me talking.

    1. Re:Perverse way to drive future CPU upgrades by misnohmer · · Score: 2

      Close, it's a great way for Intel to marginalize used PC/server market as none of the old machines get the microcode/BIOS patches. All old servers are now for air-gapped applications only.

    2. Re: Perverse way to drive future CPU upgrades by viperidaenz · · Score: 3, Insightful

      The flaws impact the CPU's in Apple products.

    3. Re:Perverse way to drive future CPU upgrades by Anonymous Coward · · Score: 5, Informative

      Or perhaps that's just the skeptic in me talking.

      I'm replying AC because this affects my company but Intel basically says in the advisory that the one mitigation that DOES affect CPU performance is not really necessary if you have a modern OS and modern web browser. I'm not certain this is true, I am not affiliated with Microsoft, GPZ, or Intel, but I do know that this issue has been researched by Intel, Microsoft, and GPZ for many months. In fact, the initial indications suggested that it was worse than it actually is after applying January microcode updates and updating OS and browser.

      That update is going to be enabled/disabled by the user based on a BIOS or OS toggle and Intel recommends it be disasbled under most circumstances. I don't know when they recommend that you enable it, but I assume it is going to be important for cloud hosting providers.

    4. Re:Perverse way to drive future CPU upgrades by Anonymous Coward · · Score: 3, Interesting

      Close, it's a great way for Intel to marginalize used PC/server market as none of the old machines get the microcode/BIOS patches. All old servers are now for air-gapped applications only.

      Responding as AC but... they have provided beta microcode back to the first core processor. I've personally seen it. The people who are NOT providing microcode updates are the hardware vendors that ship your motherboard. However, there are other ways to update the microcode, such as through your operating system. From what I have seen in beta testing, the update does not seem to affect the stability of machines with old BIOS but obviously there is no way to be certain until it starts rolling out.

    5. Re:Perverse way to drive future CPU upgrades by AmiMoJo · · Score: 3, Informative

      It's hard to take anything that Intel says seriously. Last time they said the hit would be a few percent, and people were seeing 60%.

      Best to avoid them altogether. And sue in small claims court of you are already a victim.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    6. Re:Perverse way to drive future CPU upgrades by thegarbz · · Score: 3, Insightful

      To be honest I struggle to get upset about this speculative execution business, but then I don't fall into the categories of people who need to worry. For most of these cases the exploit requires a significant chunk of privileged code to already be running. On nearly everyone's PC you have already lost. Your system is at this point no longer yours.

      Where this would be scarier is on virtual machines where one OS can break the isolation that the hypervisor provides. A computer where it's function is to give strangers access to running code on your machine.

      Frankly I think Intel is right about most of this and so is Microsoft and the Linux kernel devs when they made the various fixes for the various speculative execution bugs optional.

  2. Speed Reduction by mentil · · Score: 5, Interesting

    After all the speculative execution flaws are found and fixed (in hardware or software) the question won't be how much of a slowdown those fixes cause, but how much of a speedup from speculative execution remains.

    --
    Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
    1. Re:Speed Reduction by AmiMoJo · · Score: 4, Insightful

      The problem for Intel is that they sold these processors with certain features and performance, and now have found design defects in them.

      That's a classic consumer protection scenario. Car engine fails catastrophically after 50k km due to badly designed part? Under EU law you should not be out of pocket.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    2. Re:Speed Reduction by macraig · · Score: 4, Insightful

      Intel has been getting a free pass from such consumer protections for decades now. Are we finally so enlightened that we can take away their hoard of Get Out Of Jail Free cards and make them pay for their failures rather than profit from them?

    3. Re:Speed Reduction by jwhyche · · Score: 2

      I see where you are going with this. Basically, we have been sold a flawed product that isn't performing as advertised.

      --
      I read at +2. If your post doesn't reach that level I will not see or respond to it.
  3. Give Consumers The Option to Choose... by ad454 · · Score: 3, Interesting

    ... Security or Performance.

    Not everyone is a gamer, video editor, etc.

    Many people would gladly sacrifice 50% CPU performance, in exchange for more secure and stable processors.

    But Intel and its OEMs are reluctant to even give us consumers the choice to obtain decent microcode security fixes that slow down our computers too much.

    Intel already provides the NSA with the ME backdoor, so why won't they at least try harder to close the other security holes?

    1. Re:Give Consumers The Option to Choose... by jittles · · Score: 2

      ... Security or Performance.

      Not everyone is a gamer, video editor, etc.

      Many people would gladly sacrifice 50% CPU performance, in exchange for more secure and stable processors.

      But Intel and its OEMs are reluctant to even give us consumers the choice to obtain decent microcode security fixes that slow down our computers too much.

      Intel already provides the NSA with the ME backdoor, so why won't they at least try harder to close the other security holes?

      Read the advisory. They DID give you the option to choose and recommend that vendors ship with it disabled as it's only needed in specific circumstances.

  4. We need new benchmarks by goombah99 · · Score: 2

    The benchmark sites need to start using or disclosing speeds with the "feature" turned on.

    --
    Some drink at the fountain of knowledge. Others just gargle.
  5. cpuid by l3v1 · · Score: 2

    So, in the future CPU makers don't need to invent new names. We'll just identify CPUs with the name of the newest vulnerabilities they have :) it'll be much easier :)

    --
    I am putting myself to the fullest possible use, which is all I can think that any conscious entity can ever hope to do.
    1. Re:cpuid by Wolfrider · · Score: 3, Informative

      > So, in the future CPU makers don't need to invent new names. We'll just identify CPUs with the name of the newest vulnerabilities they have :)

      --You joke, but the Linux kernel already does this when you do ' cat /proc/cpuinfo ':

      model name : Intel(R) Core(TM) i5-x400 CPU @ 2.70GHz
      bugs : cpu_meltdown spectre_v1 spectre_v2

      --
      .
      == WolfriderV6 == I'm willing to admit that *I just might* be wrong... Are you??
  6. Re:Too names for these chips since Pentium era. by nctritech · · Score: 2

    You just listed off a couple of decades worth of Intel CPUs asking "why so many names so fast?" and none of those have the flaws being discussed nor are in common use today. What are you even talking about? I don't think you have a clue what you're saying. Every different chip has a different model number and that's a problem? What?

    ARE YOU A ROBOT