The Secure-Linux patch adds a few security features to the kernel which, while not a complete method of protection, will stop most of the 'cookbook' buffer overflow exploits cold. It also adds the option of restricting the use of symlinks and named pipes in +t (temp) directories which fixes most tmp-race exploits as well. It can also add a little bit more privacy to the system by restricting access to parts of /proc to root so that users may not see who else is logged on or what they're doing. Also tightens down file descriptors 0, 1, and 2, implements process limits and shared memory destruction, and priveledged IP aliases for kernel 2.0.
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