Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

outflux.net

Post reply on HN
Print view View original

51–60 of 61 posts

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

#51

Post by transpute »

kramerger wrote: post #34
transpute wrote: post #13

Arm memory tagging whitepaper (2019), https://developer.arm.com/-/media/Arm%20Developer%20Communit... > MTE provides a mechanism to detect both [spatial, temporal] categories of memory safety violation. MTE assists the detection of potential vulnerabilities before deployment by increasing the effectiveness of testing and fuzzing. MTE also assists detection of vulnerabilities at scale after deployment ... Memory locat…

And Googles announcement from 2019... https://security.googleblog.com/2019/08/adopting-arm-memory-...

Project Zero today, https://googleprojectzero.blogspot.com/2023/11/first-handset...

> The ability of MTE to detect memory corruption exploitation at the first dangerous access is a significant improvement in diagnostic and potential security effectiveness. The availability of MTE on a production handset for the first time is a big step forward, and I think there's real potential to use this technology to make 0-day harder.

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

#52

Post by chenxiaolong »

Per [1], I've also enabled MTE for user applications via the `persist.arm64.memtag.app_default` property. So far, the only crashes I've seen have been in apps that use cgo (eg. syncthing and rclone).

With root access, things can be persistently whitelisted on a per-app basis [2]:

    su -c 'setprop persist.arm64.memtag.app. off'
or based on basename(argv[0]) [3]:

    su -c 'setprop persist.device_config.memory_safety_native.mode_override.process. off'
[1] https://googleprojectzero.blogspot.com/2023/11/first-handset...

[2] https://cs.android.com/android/platform/superproject/main/+/...

[3] https://cs.android.com/android/platform/superproject/main/+/...

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

#53

Post by ode »

piaste wrote: post #31
galangalalgol wrote: post #29

Earlier quoted context omitted.

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.

One of GrapheneOS's absolute best features is the sandboxed Google Play Services. Basically, where other privacy AOSP forks typically offer up to three choices... - no Google at all - root and install an extremely fragile FOSS alternative GPS implementation (MicroG) - root and install the full Google Play Services binary blobs ... GrapheneOS offers option #4: you can install Google Play Services in a sandbox so that…

Does Google Wallet / NFC payments work?

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

#54

Post by telotortium »

jchw wrote: post #28
akyuu wrote: 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]

Wow, strcat - now that's not a name I've heard in a long, long time. I remember he contributed a fair deal to Rust in the early days and then blew up in a very similar fashion.

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

#55

Post by benibela »

helloooooooo wrote: post #19
maxloh wrote: post #2

Why isn't it enabled by default?

Because it keeps catching poorly written code that hasn’t yet been fixed.

Or clever code that should not be fixed

I just added my own tagging to my pointers. I have 48-bit pointers and 16-bit of tagging data.

I replaced all my struct { word type; char* data }; with something like (type << 48) | data. This saves a memory allocation and pointer indirection. It is much faster

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

#56

Post by privacyking »

telotortium wrote: post #54
jchw wrote: post #28

Earlier quoted context omitted.

[flagged]

Wow, strcat - now that's not a name I've heard in a long, long time. I remember he contributed a fair deal to Rust in the early days and then blew up in a very similar fashion.

What happened in relation to rust?

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

#57

Post by pjmlp »

hmry wrote: post #47
pjmlp wrote: post #40

Earlier quoted context omitted.

They did, MPX, however the design was buggy and eventually removed. Currently x86 is the only mainstrem architecture without a plan for hardware memory tagging. Even RISC-V has an ongoing discussion for hardware memory tagging extensions.

If AMD and Intel drag their feet long enough, CHERI will be production ready before then.

True, however unless Windows developer community finally embraces ARM, that is something that will only worry them on the server with UNIX based workloads.

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

#58

Post by vonthecreat0r »

bubblethink wrote: post #27
tcbawo wrote: post #25

Earlier quoted context omitted.

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 to…

What about the propietary blobs?

I saw @jchw stating some good point but seems most in this thread here got their head in the sand.

too much trust in a product/service that may be secure on the surface, never means it's actually secure;

I ended up installing lineageOS rooted and firewalling everything and uninstalling useless services...that's better than having a system that is being advertised as state of the art security.

How dl you think google feels if their main OS market is being taken by a "secure" alternative like Graphene OS, unless they both struck a deal or are working together behind closed doors?

I got a suspicion that there's something the lead Dev of Graphene Os is unrevealing to us...hence they put him on desk job like a rookie cop who came across some sh*t that the public shouldn't know...

Meanwhile noone can fully confirm what's inside the OEM signed blobs that are on Graphene OS and other components. What more the heavy suggestion for never rooting; when over 200k apps on the playstore are riddled with malware/spyware?

Why would a billion dollar coorp let such clumsy mistake happen? I am starting to trust the fdroid store over Googleplay (despite being unable to have access to other apps) due to the fact:

Fdroid it's community baded/ the ppl make the app out of purely enjoyment versus montary need.

I have pxl4xl and ended up uninstalling Graphene OS something feels off about it.

No company CEO/Lead Dev just have a public dispute digitally and never explain why and the very next moment they are claimed to have had a mental breakdown.

and the fact that people are asking sincere questions and are being ridiculed for it, even raises more red-flags...

Think about it;

it's 2023, people gotta start thinking for themselves, nothing seems as it awlays is based on surface exposure.

I started only using software/tools by individuals or teams where the morale or principles is non-political and is in alignment with what makes sense no matter where you apply it.

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

#59

Post by unethical_ban »

vonthecreat0r wrote: post #58
bubblethink wrote: post #27

Earlier quoted context omitted.

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 to…

What about the propietary blobs? I saw @jchw stating some good point but seems most in this thread here got their head in the sand. too much trust in a product/service that may be secure on the surface, never means it's actually secure; I ended up installing lineageOS rooted and firewalling everything and uninstalling useless services...that's better than having a system that is being advertised as state of the art s…

It's a bunch of conspiratorial nonsense.

Reading your comment and the dead comment from the other guy, I can't actually tell what the grievance is. One of the lead devs stepped away from social media? Okay?

From what others have explained, graphene OS is fully open, has a number of provable security improvements over AOSP, and has notable improvements in controlling how apps access your device.

Some healthy skepticism in security software is fine. But I don't think there's anything to what you or the other person are saying. Is there a specific portion of the project, some specific lack of reproducibility in builds or some binary blob injection you're worried about? And if a minor personnel issue is enough to make you question an entire project, maybe you should buy a dumb phone with a Faraday cage, and run slackware on a Thinkpad.

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

#60

Post by vonthecreat0r »

unethical_ban wrote: post #59
vonthecreat0r wrote: post #58

Earlier quoted context omitted.

What about the propietary blobs? I saw @jchw stating some good point but seems most in this thread here got their head in the sand. too much trust in a product/service that may be secure on the surface, never means it's actually secure; I ended up installing lineageOS rooted and firewalling everything and uninstalling useless services...that's better than having a system that is being advertised as state of the art s…

It's a bunch of conspiratorial nonsense. Reading your comment and the dead comment from the other guy, I can't actually tell what the grievance is. One of the lead devs stepped away from social media? Okay? From what others have explained, graphene OS is fully open, has a number of provable security improvements over AOSP, and has notable improvements in controlling how apps access your device. Some healthy skepticis…

[flagged]
Post reply on HN