Skip to content
By using Twitter’s services you agree to our Cookies Use. We and our partners operate globally and use cookies, including for analytics, personalisation, and ads.

This is the legacy version of twitter.com. We will be shutting it down on June 1, 2020. Please switch to a supported browser, or disable the extension which masks your browser. You can see a list of supported browsers in our Help Center.

  • Home Home Home, current page.
  • About

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?

    New to Twitter?
    Sign up
taviso's profile
Tavis Ormandy
Tavis Ormandy
Tavis Ormandy
Verified account
@taviso

Tweets

Tavis OrmandyVerified account

@taviso

Vulnerability researcher at Google. This is a personal stream, opinions expressed are mine.

California
taviso.decsystem.org
Joined April 2008

Tweets

  • © 2020 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Imprint
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list


    Under 100 characters, optional

    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. Tavis Ormandy‏Verified account @taviso 3 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @dwizzzleMSFT @mamyun

      I don't see why it couldn't work, seccomp-bpf doesn't require you to be a libc developer. I think HV containers solve a different problem.

      2 replies 0 retweets 2 likes
    2. Mehmet Iyigun‏ @mamyun 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @dwizzzleMSFT

      NT/win32k syscalls are more or less abstracted from the public API. So, exposing syscall filtering at that level would be fragile as we update Windows and as apps evolve. It needs to be exposed at a higher level. We're investigating...

      2 replies 0 retweets 1 like
    3. Dave dwizzzle Weston‏ @dwizzzleMSFT 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @mamyun @taviso

      It’s worse than that. You have NtUserMessageCall and the like which have dozens or hundreds of sub functions based on message type. Many APIs generate implicit messages. Blocking at the entry point level is way to coarse to get comparable security value to seccomp

      1 reply 0 retweets 2 likes
    4. Tavis Ormandy‏Verified account @taviso 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @dwizzzleMSFT @mamyun

      That's just plain not true Dave, it sounds like you think seccomp-bpf is just filtering based on syscall number. The "bpf" part means that there is a little turing complete program that can examine parameters, such as class or message type, and decide an action.

      4 replies 1 retweet 8 likes
    5. Mary Branscombe‏ @marypcbuk 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @dwizzzleMSFT @mamyun

      so every app gets a bpf-filtered custom sandbox that would have to be recalculated for every Windows update that touches any syscall sub function?

      1 reply 0 retweets 0 likes
    6. Tavis Ormandy‏Verified account @taviso 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marypcbuk @dwizzzleMSFT @mamyun

      Things are recalculated all the time, just loading a DLL has to recalculate offsets and relocations. I think I don't understand the complaint, the developer writes a policy, everything else can be automated.

      1 reply 0 retweets 0 likes
    7. Mary Branscombe‏ @marypcbuk 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @dwizzzleMSFT @mamyun

      that sounds very dynamic for a sandbox; does it introduce overhead?

      2 replies 0 retweets 0 likes
    8. Tavis Ormandy‏Verified account @taviso 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marypcbuk @dwizzzleMSFT @mamyun

      Not significantly, miniscule load time overhead and then miniscule syscall overhead. The alternative being pitched here is spinning up a HV container.... now that's overhead 🤣

      1 reply 0 retweets 0 likes
    9. Mary Branscombe‏ @marypcbuk 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @taviso @dwizzzleMSFT @mamyun

      doesn't that depend on whether it's a full HV VM for the container or a minimal process with no HV services like LSASS or shared memory and scheduling like the new Sandbox (where the overhead is *installing the whole damn app* every time)

      1 reply 0 retweets 0 likes
    10. Mary Branscombe‏ @marypcbuk 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marypcbuk @taviso and

      I'd really like a version of the sandbox that completely isolated an app from Windows so it can't dig its tentacles in but also doesn't have to be installed from scratch every time

      1 reply 0 retweets 1 like
      Tavis Ormandy‏Verified account @taviso 4 Feb 2019
      • Report Tweet
      • Report NetzDG Violation
      Replying to @marypcbuk @dwizzzleMSFT @mamyun

      Either way, we're talking orders of magnitude more overhead. It's either just many orders of magnitude or many many many orders of magnitude.

      10:22 AM - 4 Feb 2019
      • 1 Like
      • Damien Miller
      1 reply 0 retweets 1 like
        1. Hassan Sultan‏ @hsultan75 4 Feb 2019
          • Report Tweet
          • Report NetzDG Violation
          Replying to @taviso @marypcbuk and

          I think the problem with the approach is : 1) lack of tooling to generate the metadata reliably 2) risk of things going haywire if done wrong with dependencies 3) with enough dependencies, the tree becomes so large that you lose the filtering, unless your metadata is per-fn

          0 replies 0 retweets 0 likes
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2020 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Imprint
        • Cookies
        • Ads info