Extra:Meltdown Spectre
From COMP15212 Wiki
Two security flaws in a number of different high-performance processors came to (prominent) public notice in January 2018; these were codenamed “Meltdown” and “Spectre”.
The issues involve the potential leaking of supposedly protected (secret) information via side-channels – i.e. secondary effects which a supposedly isolated system can observe.
Details are somewhat sketchy, at time of writing, and sufficiently complicated to be beyond the main intent of this module. More details can be found here.
However, there are some important points which these cases exemplify:
- Problems arise from an unpredicted combination of circumstances, here including processor architecture – speculative pipelining and cache behaviour – and virtualisation and protection in the operating system. Several ‘different’ areas overlap in an embarrassing way!
- Performance optimisations – in this case hardware but this is not always the case – can be the enemy of security.
- These are architectural issues (concepts) in processor hardware which affect different ISAs, as well as different implementations.
Articles on Security
Buffer Overflow • Containers • Context • Disk Partition • File Attributes • File Permissions • Journalling File System • Mutual exclusion • Processor Privilege • SETUID • Security
