11–20 of 61 posts
Earlier quoted context omitted.
Memory Tagging Extension, an arm v9 hardware feature for mitigating some memory safety bugs.
Is this the outcome of the Morello project? Honestly sounds nice.
Earlier quoted context omitted.
Memory Tagging Extension, an arm v9 hardware feature for mitigating some memory safety bugs.
Is this the outcome of the Morello project? Honestly sounds nice.
This page explains it pretty well: https://msrc.microsoft.com/blog/2022/01/an_armful_of_cheris/
> 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 locations are tagged by adding four bits of metadata to each 16 bytes of physical memory. This is the Tag Granule. Tagging memory implements the lock. Pointers, and therefore virtual addresses, are modified to contain the key.
Earlier quoted context omitted.
Is this the outcome of the Morello project? Honestly sounds nice.
CHERI vs MTE is a bit of a nuanced topic. At least one part of the limiting factor for MTE is that you get a finite number of tag “color codes” which opens the opportunity for some form of probabilistic attacks. Of course this helps with defense in depth as it’s yet another layer of security, but it isn’t as strong of a prevention as a CHERI capability for example. This page explains it pretty well: https://msrc.micr…
Does x86 have something comparable?
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…
Why isn't it enabled by default?
There's probably a very good reason for it. I would definitely advice anyone against enabling "Developer options" on your phone without having a good understanding what those options do. They are hidden and hard to access for a reason.
Such as animation speed. I hate _so much_ all the wobblyness of the GUI! Everything bouncing, sliding, and hovering around. Thankfully one can enable Developer options and set all that stuff to 0x, which effectively disables everything and now the system becomes crisp and instant, as it should be.
Another essential setting for saving much precious battery, is to not have the cellular data active at all times even when WiFi is active. If I come home and enable wifi, I do not want the cellular data to stay active too in the background. It's much better waiting the couple seconds it might take to switch networks, in exchange for some extra juice.
Why isn't it enabled by default?
Earlier quoted context omitted.
There's probably a very good reason for it. I would definitely advice anyone against enabling "Developer options" on your phone without having a good understanding what those options do. They are hidden and hard to access for a reason.
Sadly they contain some options which ought to be part of the normal system settings, but they aren't. Such as animation speed. I hate _so much_ all the wobblyness of the GUI! Everything bouncing, sliding, and hovering around. Thankfully one can enable Developer options and set all that stuff to 0x, which effectively disables everything and now the system becomes crisp and instant, as it should be. Another essential…