Editing Buffer overflow protection (section)

==Tagging==
Tagging<ref>{{cite web |url=http://www.feustel.us/Feustel%20&%20Associates/Advantages.pdf |title=Tuesday, April 05, 2005 |website=Feustel.us |access-date=2016-09-17 |archive-url=https://web.archive.org/web/20160623195112/http://www.feustel.us/Feustel%20%26%20Associates/Advantages.pdf |archive-date=June 23, 2016 |url-status=dead }}</ref> is a compiler-based or hardware-based (requiring a [[tagged architecture]]) technique for tagging the type of a piece of data in memory, used mainly for type checking. By marking certain areas of memory as non-executable, it effectively prevents memory allocated to store data from containing executable code. Also, certain areas of memory can be marked as non-allocated, preventing buffer overflows.

Historically, tagging has been used for implementing high-level programming languages;<ref>{{cite journal |title=Tags and type checking in LISP: hardware and software approaches |year=1987 |publisher=ACM|doi=10.1145/36204.36183 |last1=Steenkiste |first1=Peter |last2=Hennessy |first2=John |journal=ACM SIGOPS Operating Systems Review |volume=21 |issue=4 |pages=50–59 |doi-access=free }}</ref> with appropriate support from the [[operating system]], tagging can also be used to detect buffer overflows.<ref>{{cite web |url=http://public.support.unisys.com/aseries/docs/clearpath-mcp-11.0/pdf/38347639-000.pdf |title=ClearPath Enterprise Servers MCP Security Overview |publisher=Public.support.unisys.com |access-date=2014-04-27 |archive-url=https://web.archive.org/web/20130124070111/http://public.support.unisys.com/aseries/docs/clearpath-mcp-11.0/pdf/38347639-000.pdf |archive-date=2013-01-24 |url-status=dead }}</ref>  An example is the [[NX bit]] hardware feature, supported by [[Intel]], [[AMD]] and [[ARM architecture|ARM]] processors.