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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.

43 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 Anonymous Coward · · Score: 1

      Just to note, commercially available computers are buggy, insecure POS's

      This has been noted before, particularly in reviews for acceptable levels of security that used to require a PC have no network, keyboard or monitor, and be in a locked room in order to be considered secure.

      Why this surprises anybody is beyond me, maybe the gov will slip up and let us all have the specs for whatever Multics led to

    2. 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.

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

      The flaws impact the CPU's in Apple products.

    4. 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.

    5. 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.

    6. Re: Perverse way to drive future CPU upgrades by Anonymous Coward · · Score: 1

      Only if you hold it The wrong way

    7. 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
    8. 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 Anonymous Coward · · Score: 1

      On on any machine that uses SMM, for the matter.

    4. Re:Speed Reduction by AmiMoJo · · Score: 1

      Yes. I took then to small claims court and won.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    5. Re:Speed Reduction by thegarbz · · Score: 1

      Car engine fails catastrophically after 50k km due to badly designed part? Under EU law you should not be out of pocket.

      The car engine didn't fail catastrophically. What did happen is you applied an optional fix to a problem that under a very small set of specific circumstances would cause the car door to unlock and then after you put your car with its optional fix on a dyno you discovered you actually had 10 horsepower less than you thought.

      You'll be hard pressed getting that through even an EU regulator.

    6. Re:Speed Reduction by ravenshrike · · Score: 1

      Yes and no. You could with new model cars that they knew they were going to be applying the fix to in the coming months but sold under the old numbers. Specifically that would be fraud, so anyone who bought Coffee Lake before the fixes were published is arguably entitled to a full refund.

    7. Re:Speed Reduction by thegarbz · · Score: 1

      so anyone who bought Coffee Lake before the fixes were published is arguably entitled to a full refund

      Not really because Intel don't publish performance figures, hence it isn't fraud. Not only that but the processor itself still does exactly what it said on the box. The fact that someone else can use those feature nefariously and that Intel gives you an option for added security at the cost of performance doesn't change what the processor is now and what it will be after the optional fix gets released.

      The key part here is that you still have every bit the same device that was advertised and sold to you doing exactly what it says on the box.

      It may not be moral, but you will almost certainly fail to prove a fraud case.

    8. 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.
    9. Re:Speed Reduction by macraig · · Score: 1

      And if we individually sued them for something that is a collective wrong, we'd tie up the judicial system for decades with a waiting list encircling the globe several times, wouldn't we? I'm glad "you got yours", but that's not a solution for the societal wrong, is it?

    10. Re:Speed Reduction by AmiMoJo · · Score: 1

      I'm such cases the judges usually start fast tracking decisions based on previous cases, and then to save paying court and legal fees the company just pays out without contest in future.

      It sucks but there is no other option.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
  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.

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

      Not everyone is a gamer, video editor, etc.

      But who doesn't re-edit their porn to match their own stroke rate?

      --
      Table-ized A.I.
    3. Re:Give Consumers The Option to Choose... by Bert64 · · Score: 1

      If one vendor cuts corners to improve performance the other vendors will look like their products are slower until such time as the corner cutting is identified and can be proven to be detrimental.

      --
      http://spamdecoy.net - free throwaway anonymous email - avoid spam!
    4. Re:Give Consumers The Option to Choose... by thegarbz · · Score: 1

      Not everyone is a gamer, video editor, etc.

      Pfft amateurs. What do they need a decent CPU for. Real men need Real CPUs for Real workloads like running McAfee.

    5. Re:Give Consumers The Option to Choose... by Killall+-9+Bash · · Score: 1

      The market as a whole chooses performance to play games and download porn 0.015% faster over security every single time. So that's what is broadly and cheaply available.

      The market was not given a choice. No one said "Intel chips are 50% faster, but possibly vulnerable to security exploits". NO ONE, if they were informed, would have made this choice.

      --
      "Prediction: within 10 years, Windows will be a Linux distribution." Me, 7-6-2016
    6. Re:Give Consumers The Option to Choose... by bluefoxlucid · · Score: 1

      This will never be in OpenBSD. Back in 2005, Theo de Raadt would not give any ground when I implored him to build with position independent executables. He maintained that PIE was "very expensive"--the overall impact on x86 is about 0.06% additional CPU usage, so about 2.16 seconds lost per hour pegged at 100% CPU usage, minus any time spent not at 100% CPU usage.

      8%? He'll never accept that. It's way too performance-expensive.

      --
      Support my political activism on Patreon.
    7. Re: Give Consumers The Option to Choose... by bn-7bc · · Score: 1

      You are right, but rgere are far more intel costumers thst care about performance than gamers and wideo editors, SaAS providers, metreologists, intel sells to other costumers than consumers. i would imagine rhat googlebwould not be thrilled if the 1000s of servers they run in a Dc dropped even 1% in performance, that would potenttionsly mean 100s of extra servers to do the same amount of work wit extra switchports power an cooling, not cheap

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

      Google and Microsoft are shielding Intels reputational damage, Intel should be making these announcements, and with detail.

      Intel has no right to announce this. Microsoft and Google both found the issue. They reported it to Intel. Intel did make a disclosure, albeit not a very detailed one. Microsoft and Google receive the accolades for telling the world about this problem. This is how it always works in the world of security research. The researcher agrees to postpone publishing while the issue is mitigated and the company they reported to agrees to keep the research in the strictest confidentiality until they publish. It’s only fair.

      Intel dont appear keen to supply owners of defective cpus with the tools to choose, but trickle bios settings to verndor who may or maynot retrofit to 10 year old product. My generic chromebook/laptop whose brand went belly up going to be fixed?

      Your manufacturer will likely not update the BIOS for any system more than 2-3 years old unless a longer support contract was previously established. However, the fix can be delivered through your OS. Intel has plans to release microcode back to the second gen core processors (sandy bridge). That’s 8-10 years of mitigation.

      I want to know what other CPU's were affected.

      Intel and ARM. Likely AMD also but no one has said either way to my knowledge. Any other processor? YOu might want to perform the research yourself as less common platforms like PPC and MIPS are not likely to receive much attention from researchers.

      I suggest the performance decrease is measured AFTER MS and Goolge recompiled speculative bits out of their base code, so the slowdown figures are less than a like for like.

      So update your microcode and OS and enable and disable the change and test for yourself. Everyone’s usage scenarios will be different. It’ll depend entirely on how you use your computer. Whether you need the mitigation enabled or disabled depends entirely on how you use your computer, too.

      Intel may actually profit from defective design. Who knows when Intel knew this, and if they did, why did the propogate that design to others,

      This type of attack has been known of in theory since the first Pentium (the first processor with this type of speculative execution). But nobody thought it was actually possible until someone proved it was possible. Just like scientists knew about nuclear fission in theory but didn’t know if a nuclear bomb was possible until the first one was built.

      Just wait untl Google takes apart the now vulnerable ME engine with disclosures. If they dont, others will.

      Now if the ME engine does not have speculative execution and other known CVE's then the why questions become interesting.

      There have been PLENTY of advisories related to Intel ME, AMD PSP, and most likely ARM TrustZone. I have seen advisories for the first two. So people are already attacking the ME engine. The same mitigations that are used for side-channel analysis can also be used to mitigate the secure processor on all of those platforms. However, I am positive that more vulnerabilities still exist

  4. And he laughed... by DivineKnight · · Score: 1

    And my professor laughed when I held the single-cycle CPU design to be the holy grail of the industry...

  5. 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.
  6. Great! by Anonymous Coward · · Score: 1

    When this is all done and dusted I will be left with a z80

    1. Re: Great! by Bing+Tsher+E · · Score: 1

      I have several tubes of Z80s and two working systems that use that processor.

  7. Newspeak by Anonymous Coward · · Score: 1

    > The firmware updates will set the Speculative Store Bypass protection to off-by-default, ensuring that most people won't see negative performance impacts.

    Devices will remain insecure by default to protect our brand image and shareholders. How the f* do you think it is a good idea to set a security patch as off-by-default?

  8. 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??
  9. Again differences... by DrYak · · Score: 1

    This time it depends on both the CPU and the OS.

    This is basically a "read-after-write" situation, where the CPU tries to speculate before the write is actually known.

    Depending on your CPU + OS combo, this will be limited to data you already have full read/write access to anyway.
    (AMD doesn't speculated pass memory protection, Intel does(*).
    Linux use a copy-on-write memory allocation scheme, that grantees that all memory page seen by an application are magically pre-filled with zero, meaning that an application can never(*) see some other application's remaining data. But other OSes may differ - I have no idea and don't bother enough to check).

    So on AMD arch + Linux OS, all you're ever going to see it is the apps own (non overwritten) data.
    (Well unless there's a new "kernel stack information leak" that gets discovered - basically the kernel leaving dangerous stuff lingereing on the stack)

    So it mostly affect situation like browsers where 3rd party provided code (eg.: internet downloaded javascript) could run in the same process context as some critical bits of information (say a password management plugin).

    It should not effect kernel or hypervisor.

    ---

    (*) + (*) I'm almost ready to bet that somebody will find discover an intel-specific exploit to speculatively execute around page faults.

    --
    "Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
    1. Re:Again differences... by jittles · · Score: 1

      It should not effect kernel or hypervisor.

      I know for a fact that Intel notified VMWare of these vulnerabilities and told them they needed to patch ESXi. These can be exploited through a hypervisor.

  10. 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

  11. Where is Firefox? by short · · Score: 1

    "Safari, Edge, and Chrome" - but where is Firefox? Then also Chromium but that is assumed to be patched along with Chrome. Nobody cares about Free software anymore?

  12. Re:mo3 down by Killall+-9+Bash · · Score: 1

    WARNING: this link goes to domain squatting malware shitware, not a graphic pic of a horse-fucker stretching out his anus. You may be disappointed.

    --
    "Prediction: within 10 years, Windows will be a Linux distribution." Me, 7-6-2016
  13. Re: Buy AMD by Killall+-9+Bash · · Score: 1

    I ignore Ryzenfall because I don't expect the processor to protect me if hackers already have admin on my box.

    --
    "Prediction: within 10 years, Windows will be a Linux distribution." Me, 7-6-2016
  14. Fixes should be called Melter and SpecDown by technosaurus · · Score: 1

    Planned obsolescence at its best.