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> Prior to the Release of Android 10 we announced a new constrained sandbox for software codecs. We’re really pleased with the results. Thus far, Android 10 is

by mtgx 6y ago

> Prior to the Release of Android 10 we announced a new constrained sandbox for software codecs. We’re really pleased with the results. Thus far, Android 10 is the first Android release since the infamous stagefright vulnerabilities in Android 5.0 with zero critical-severity vulnerabilities in the media frameworks. It wasn't mediatized, but there must have been like a new stagefright-like media library bug every 2-3 months since stagefright was first publicized. Glad to see this news. Also, how are they enabling memory tagging if it's an Arm v8.5 feature and new Arm CPUs, except for Apple's own chips, don't seem to support newer than Arm v8.2? Is it just the software version of memory tagging (with some expected performance penalty)?

pjmlp 6y ago
Modern ARM chips are required for Android 11 versions. https://security.googleblog.com/2019/08/adopting-arm-memory-tagging-extension.html https://security.googleblog.com/2019/08/adopting-arm-memory-... https://source.android.com/devices/tech/debug/tagged-pointers https://source.android.com/devices/tech/debug/tagged-pointer...
- saagarjha 6y ago
  You've mentioned this before but as far as I am aware there are no chips shipping with MTE, and the links you provided don't support this point either. Even if MTE somehow starts shipping tomorrow I cannot see Google dropping support for every device that is older or cheaper than the one flagship that'll use it.
  - pjmlp 6y ago
    The official statement, is from Google and ARM, not from me. From my links above, the TL;DR; snippets are > Google is committed to supporting MTE throughout the Android software stack. We are working with select Arm System On Chip (SoC) partners to test MTE support and look forward to wider deployment of MTE in the Android software and hardware ecosystem. > Starting in Android R, for 64-bit processes, all heap allocations have an implementation defined tag set in the top byte of the pointer on devices with kernel support for ARM Top-byte Ignore (TBI). Any application that modifies this tag is terminated when the tag is checked during deallocation. This is necessary for future hardware with ARM Memory Tagging Extension (MTE) support. And from https://android-developers.googleblog.com/2020/02/Android-11-developer-preview.html https://android-developers.googleblog.com/2020/02/Android-11... > We’re also enabling heap pointer tagging for apps targeting Android 11 or higher, to help apps catch memory issues in production. These hardening improvements may surface more repeatable/reproducible app crashes in your code, so please test your apps. For the chips without MTE they plan to configure the kernel to randomly target processes for fuzzing. https://android-developers.googleblog.com/2020/04/android-11-developer-preview-3.html https://android-developers.googleblog.com/2020/04/android-11... https://developer.android.com/ndk/guides/gwp-asan https://developer.android.com/ndk/guides/gwp-asan > GWP-ASan heap analysis - Android 11 uses a variety of tools to harden security-critical components in the platform and apps. In DP3, we’re adding GWP-ASan as another way to help developers find and fix memory safety issues. GWP-ASan is a sampling allocation tool that detects heap memory errors with minimal overhead or impact on performance. We’ve enabled GWP-ASan to run by default in platform binaries and system apps, and now you can now enable it for your apps as well. If your app uses native code or libraries, we recommend enabling GWP-ASan and testing as soon as possible. > GWP-ASan is enabled on some randomly-selected system applications and platform executables upon process start-up (or when the zygote forks) And from ARM official communication, https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/enhancing-memory-safety https://community.arm.com/developer/ip-products/processors/b... > Only recently, Google announced that it is adopting Arm’s MTE in Android. This is exciting news, with Google showing its continued commitment to security in the Android ecosystem. It also shows the strength of our MTE offering, with the article stating that the technology makes “it very hard (if not impossible) to exploit memory bugs.” Alongside the security benefits, the disruption caused by not addressing memory safety bugs reduces user satisfaction and increases the cost of software development. With all these threats to the Android Ecosystem, you can understand why Google has made the commitment to MTE! So those are the words from Google's Android team and ARM, whatever ARM CPU are being shipped, or alternative CPUs that Android devices might still adopt or be using.
    - saagarjha 6y ago
      Right, all those seem to point to greater MTE support and hardware tagging when available. But I don’t think any claim that Android 11 requires a new chip to be supported?
      - pjmlp 6y ago
        Maybe it is my lack of native English understanding, but I read sentences like this one "Only recently, Google announced that it is adopting Arm’s MTE in Android." in another way as you do. It doesn't make sense adopting support for non-existing hardware.
        saagarjha 6y ago
        Ah, I see the confusion. I interpreted https://news.ycombinator.com/item?id=23695227 https://news.ycombinator.com/item?id=23695227 as “this is a requirement of Android 11 and as such you can’t run the OS at all if you don’t have the new hardware supporting it”.
        pjmlp 6y ago
        That as well, from Android documentation I understand this, > GWP-ASan is enabled on some randomly-selected system applications and platform executables upon process start-up (or when the zygote forks). Enable GWP-ASan in your own app to help you find memory-related bugs, and to prepare your app for ARM Memory Tagging Extension (MTE) support. The allocation sampling mechanisms also provide reliability against queries of death. As stop gap solution until MTE is widespread across all Android devices.

by mtgx 6y ago

pjmlp 6y ago

Modern ARM chips are required for Android 11 versions. https://security.googleblog.com/2019/08/adopting-arm-memory-tagging-extension.html https://security.googleblog.com/2019/08/adopting-arm-memory-... https://source.android.com/devices/tech/debug/tagged-pointers https://source.android.com/devices/tech/debug/tagged-pointer...

saagarjha 6y ago
You've mentioned this before but as far as I am aware there are no chips shipping with MTE, and the links you provided don't support this point either. Even if MTE somehow starts shipping tomorrow I cannot see Google dropping support for every device that is older or cheaper than the one flagship that'll use it.
- pjmlp 6y ago
  The official statement, is from Google and ARM, not from me. From my links above, the TL;DR; snippets are > Google is committed to supporting MTE throughout the Android software stack. We are working with select Arm System On Chip (SoC) partners to test MTE support and look forward to wider deployment of MTE in the Android software and hardware ecosystem. > Starting in Android R, for 64-bit processes, all heap allocations have an implementation defined tag set in the top byte of the pointer on devices with kernel support for ARM Top-byte Ignore (TBI). Any application that modifies this tag is terminated when the tag is checked during deallocation. This is necessary for future hardware with ARM Memory Tagging Extension (MTE) support. And from https://android-developers.googleblog.com/2020/02/Android-11-developer-preview.html https://android-developers.googleblog.com/2020/02/Android-11... > We’re also enabling heap pointer tagging for apps targeting Android 11 or higher, to help apps catch memory issues in production. These hardening improvements may surface more repeatable/reproducible app crashes in your code, so please test your apps. For the chips without MTE they plan to configure the kernel to randomly target processes for fuzzing. https://android-developers.googleblog.com/2020/04/android-11-developer-preview-3.html https://android-developers.googleblog.com/2020/04/android-11... https://developer.android.com/ndk/guides/gwp-asan https://developer.android.com/ndk/guides/gwp-asan > GWP-ASan heap analysis - Android 11 uses a variety of tools to harden security-critical components in the platform and apps. In DP3, we’re adding GWP-ASan as another way to help developers find and fix memory safety issues. GWP-ASan is a sampling allocation tool that detects heap memory errors with minimal overhead or impact on performance. We’ve enabled GWP-ASan to run by default in platform binaries and system apps, and now you can now enable it for your apps as well. If your app uses native code or libraries, we recommend enabling GWP-ASan and testing as soon as possible. > GWP-ASan is enabled on some randomly-selected system applications and platform executables upon process start-up (or when the zygote forks) And from ARM official communication, https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/enhancing-memory-safety https://community.arm.com/developer/ip-products/processors/b... > Only recently, Google announced that it is adopting Arm’s MTE in Android. This is exciting news, with Google showing its continued commitment to security in the Android ecosystem. It also shows the strength of our MTE offering, with the article stating that the technology makes “it very hard (if not impossible) to exploit memory bugs.” Alongside the security benefits, the disruption caused by not addressing memory safety bugs reduces user satisfaction and increases the cost of software development. With all these threats to the Android Ecosystem, you can understand why Google has made the commitment to MTE! So those are the words from Google's Android team and ARM, whatever ARM CPU are being shipped, or alternative CPUs that Android devices might still adopt or be using.
  - saagarjha 6y ago
    Right, all those seem to point to greater MTE support and hardware tagging when available. But I don’t think any claim that Android 11 requires a new chip to be supported?
    - pjmlp 6y ago
      Maybe it is my lack of native English understanding, but I read sentences like this one "Only recently, Google announced that it is adopting Arm’s MTE in Android." in another way as you do. It doesn't make sense adopting support for non-existing hardware.
      - saagarjha 6y ago
        Ah, I see the confusion. I interpreted https://news.ycombinator.com/item?id=23695227 https://news.ycombinator.com/item?id=23695227 as “this is a requirement of Android 11 and as such you can’t run the OS at all if you don’t have the new hardware supporting it”.
        pjmlp 6y ago
        That as well, from Android documentation I understand this, > GWP-ASan is enabled on some randomly-selected system applications and platform executables upon process start-up (or when the zygote forks). Enable GWP-ASan in your own app to help you find memory-related bugs, and to prepare your app for ARM Memory Tagging Extension (MTE) support. The allocation sampling mechanisms also provide reliability against queries of death. As stop gap solution until MTE is widespread across all Android devices.