4 ms·
Many of the items on this list seem to be some variation of "random place in memory so attackers can't guess" It sounds nice, but can someone explain if there
by jimmy1 8y ago
Many of the items on this list seem to be some variation of "random place in memory so attackers can't guess"
It sounds nice, but can someone explain if there are any downsides?
- snazz 8y agoSlightly slower? Mechanical hard drive boot times aren’t the best, but they’re quite acceptable with an SSD. For my desktop use, OpenBSD seems plenty fast.
- futureastronaut 8y agoI think you're confusing topics, randomized address space != random disk reads. Edit: To answer GP's question, you're probably already incurring a cache miss if you're pointer chasing so in most cases there should be no effect on performance.
- oherrala 8y agoNo, OpenBSD randomizes symbols on kernel and some libraries (for example libc). This randomization is done on boot. From https://www.openbsd.org/innovations.html https://www.openbsd.org/innovations.html: > Library order randomization: In rc(8), re-link libc.so, libcrypto, and ld.so on startup, placing the objects in a random order. Theo de Raadt and Robert Peichaer, May 2016, enabled by default since OpenBSD 6.0 and 6.2. and > Kernel relinking at boot: the .o files of the kernel are relinked in random order from a link-kit, before every reboot. This provides substantial interior randomization in the kernel's text and data segments for layout and relative branches/calls. Basically a unique address space for each kernel boot, similar to the userland fork+exec model described above but for the kernel. Theo de Raadt, June 2017.
- cat199 8y agosoftware written in other environments may fail due to assumptions of non randomness, and so need patching to work on openbsd. on the upside, these changes often improve overall security of the code and are merged upstream so those using other OS's benefit.