Prelink and address space randomization [LWN.net]

Prelink and address space randomization

Posted Jul 6, 2006 21:08 UTC (Thu) by oak (subscriber, #2786)
Parent article: Prelink and address space randomization

Prelink also saves memory because relocating symbols dirties the memory
pages on which the symbols are (makes that memory private for the
process). For servers running many instances of the same binaries this
could be significant. However, they could to prelink only most used
binaries...

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Prelink and address space randomization

Posted Jul 7, 2006 0:49 UTC (Fri) by nix (subscriber, #2304) [Link]

prelinking only the most used binaries won't necessarily help; that will necessarily prelink libc and ld.so as well, and while these will benefit from ASLR when a non-prelinked app is run, if the attacker can wander around the libc's ELF structures it can determine what its preferred load address is in any case, even though it wasn't actually loaded there.

Personally, I prelink non-network-exposed systems only (and make my network-exposed systems stripped-down UML instances).