Strict memcpy() bounds checking for the kernel

The C programming language is famously prone to memory-safety problems that lead to buffer overflows and a seemingly endless stream of security vulnerabilities. But, even in C, it is possible to improve the situation in many cases. One of those is the memcpy() family of functions, which are used to efficiently copy or overwrite blocks of memory; with a bit of help from the compiler, those functions can be prevented from writing past the end of the destination object they are passed. Enforcing that condition in the kernel is harder than one might expect, though, as this massive patch set from Kees Cook shows.

Full Story (comments: 16)