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Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

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Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#22
post #10

Consider using GrapheneOS instead of stock Android for an improved version of MTE (and extra security and privacy as a bonus): https://discuss.grapheneos.org/d/8439-mte-support-status-for... > Stock Pixel OS has it as a developer option which isn't usable in practice since it breaks far too much. The implementation is also much less powerful than hardened_malloc. > We integrated it into hardened_malloc where it's abl…

Writing this from a Pixel running GrapheneOS. I've been away from Graphene (using Lineage) since the CopperheadOS days. Coming back I can safely say I will be buying Pixels as long as GrapheneOS is around. The robustness a finish is just amazing.

To anyone using a Pixel: install and donate (if you can)!

The web installer[1] is basically a few clicks on a web page. So damned impressed.

[1] https://grapheneos.org/install/web

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#23

Sounds very useful. Even just for testing. Does x86 have something comparable?

Yes. Kind of.

AMD processors have Upper Address Ignore (UAI) with 7 bits of ancillary data, for Intel there is Linear Address Masking (LAM) with 6 or 15 bits [1]. The latter has made it into Linux after some initial resistance [2].

[1]: https://lwn.net/Articles/888914

[2]: https://www.phoronix.com/news/Intel-LAM-Merged-Linux-6.4

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#24

Sounds very useful. Even just for testing. Does x86 have something comparable?

Yes. Kind of. AMD processors have Upper Address Ignore (UAI) with 7 bits of ancillary data, for Intel there is Linear Address Masking (LAM) with 6 or 15 bits [1]. The latter has made it into Linux after some initial resistance [2]. [1]: https://lwn.net/Articles/888914 [2]: https://www.phoronix.com/news/Intel-LAM-Merged-Linux-6.4

Those sound analogous to the TBI feature in Arm, rather than MTE itself (which uses TBI).

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#25
post #10

Consider using GrapheneOS instead of stock Android for an improved version of MTE (and extra security and privacy as a bonus): https://discuss.grapheneos.org/d/8439-mte-support-status-for... > Stock Pixel OS has it as a developer option which isn't usable in practice since it breaks far too much. The implementation is also much less powerful than hardened_malloc. > We integrated it into hardened_malloc where it's abl…

Coming from an absolute outsider (recent ambivalent iPhone switch, previously Android), how can I know that GrapheneOS is secure and the provenance of my build is legitimate, so that I can trust it with my banking, email, photos, identity, etc.?

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#26
post #25
post #10

Consider using GrapheneOS instead of stock Android for an improved version of MTE (and extra security and privacy as a bonus): https://discuss.grapheneos.org/d/8439-mte-support-status-for... > Stock Pixel OS has it as a developer option which isn't usable in practice since it breaks far too much. The implementation is also much less powerful than hardened_malloc. > We integrated it into hardened_malloc where it's abl…

Coming from an absolute outsider (recent ambivalent iPhone switch, previously Android), how can I know that GrapheneOS is secure and the provenance of my build is legitimate, so that I can trust it with my banking, email, photos, identity, etc.?

Builds are reproducible [1], so you can compile them yourself and check they match the official ones. Additionally, official releases are signed and the update client verifies them and prevents downgrade attacks [2]. You can also install updates offline from a computer if you prefer [3].

[1] https://grapheneos.org/build#reproducible-builds

[2] https://grapheneos.org/releases#about-the-releases

[3] https://grapheneos.org/usage#updates-sideloading

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#27
post #25
post #10

Consider using GrapheneOS instead of stock Android for an improved version of MTE (and extra security and privacy as a bonus): https://discuss.grapheneos.org/d/8439-mte-support-status-for... > Stock Pixel OS has it as a developer option which isn't usable in practice since it breaks far too much. The implementation is also much less powerful than hardened_malloc. > We integrated it into hardened_malloc where it's abl…

Coming from an absolute outsider (recent ambivalent iPhone switch, previously Android), how can I know that GrapheneOS is secure and the provenance of my build is legitimate, so that I can trust it with my banking, email, photos, identity, etc.?

Provenance -> They have a bunch of tooling including attestation that you can use to verify your OS. GrapheneOS also operates like the stock OS with a locked bootloader, just signed with their keys, and the integrity of the boot chain up to and including the OS is what the attenstation app can verify after an initial pairing.

Secure -> It's code. There are no absolute guarantees. They have security enhancements on top of AOSP. So that's a rough proxy for what you should expect.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#28
post #10

Consider using GrapheneOS instead of stock Android for an improved version of MTE (and extra security and privacy as a bonus): https://discuss.grapheneos.org/d/8439-mte-support-status-for... > Stock Pixel OS has it as a developer option which isn't usable in practice since it breaks far too much. The implementation is also much less powerful than hardened_malloc. > We integrated it into hardened_malloc where it's abl…

[flagged]

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#29
post #22
post #10

Consider using GrapheneOS instead of stock Android for an improved version of MTE (and extra security and privacy as a bonus): https://discuss.grapheneos.org/d/8439-mte-support-status-for... > Stock Pixel OS has it as a developer option which isn't usable in practice since it breaks far too much. The implementation is also much less powerful than hardened_malloc. > We integrated it into hardened_malloc where it's abl…

Writing this from a Pixel running GrapheneOS. I've been away from Graphene (using Lineage) since the CopperheadOS days. Coming back I can safely say I will be buying Pixels as long as GrapheneOS is around. The robustness a finish is just amazing. To anyone using a Pixel: install and donate (if you can)! The web installer[1] is basically a few clicks on a web page. So damned impressed. [1] https://grapheneos.org/insta…

Do you lose the whole play store? Does it even make sense if I use gmail? I like the idea at least. And my 4a isn't getting updates now(on graphene either apparently) which is a shame because I still like it. I used to ise lineage on Samsung devices.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#30
post #28
post #10

Consider using GrapheneOS instead of stock Android for an improved version of MTE (and extra security and privacy as a bonus): https://discuss.grapheneos.org/d/8439-mte-support-status-for... > Stock Pixel OS has it as a developer option which isn't usable in practice since it breaks far too much. The implementation is also much less powerful than hardened_malloc. > We integrated it into hardened_malloc where it's abl…

[flagged]

> What I'd hope to hear is that Daniel Micay is in better mental health, but they made the almost-certainly wise choice to stop engaging with social media, and I can't find much information about what actually went down, so I guess it's a question mark.

I mean, it sounds like you have pretty much all the relevant information already?

strcat's technical chops were AFAIK never in question, but he had a tendency to pick up loud internet fights - to be fair, sometimes the other party were also being hostile jerks, but sometimes they weren't and he'd just swing at shadows.

After he pissed off Rossmann, he either realized or someone close to him made him realize (doesn't really matter which) that he should step away from the public square, and he did. Now he's just an ordinary, and I presume highly valued, contributor to GrapheneOS and to upstream AOSP.

Whether he still lurks the GrapheneOS discussion threads or not, or whether he is currently undergoing therapy or just chilling with a good book isn't really anyone else's business.

What else do you need to know?

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