What's this about?
GrapheneOS reports the Pixel 11 no longer supports hardware memory tagging (MTE), a feature Pixel devices had carried and that GrapheneOS used aggressively.
What is memory tagging?
A hardware feature that catches memory-safety bugs at runtime. Every allocation gets a small tag, and every pointer carries the tag of what it was supposed to point at; if they disagree, the hardware faults. That turns the most exploited bug class in existence — use-after-free and buffer overflows in C and C++ — from a silent exploitable condition into an immediate crash. It is one of the few mitigations that raises the cost of exploitation by a large multiple rather than a small one.
Why does this matter to you?
HN 312 points, 186 comments
- Losing MTE is a genuine regression in exploit mitigation on the device most associated with it, and it is not obviously replaceable in software.
- It matters most for the hardened-Android community, which had built its threat model around the feature being present.
- The broader lesson for anyone depending on hardware mitigations: they are a vendor's product decision, and they can be withdrawn.