[$] Killing processes that don’t want to die

Post Syndicated from jake original https://lwn.net/Articles/754980/rss

Suppose you have a program on your system that you don’t quite
. Maybe it’s a program submitted by a student to an automated
grading system. Or maybe it’s a QEMU device model running in a Xen
control domain ("domain 0" or “dom0”), and you want to make sure
that even
if an attacker from a rogue virtual machine manages to take over the QEMU
process,
they can’t do any further harm. There are many you want to do as far
as restricting its ability
to do mischief. But one thing in particular you probably want to do
is to be able to reliably kill the process once you think it should be
done. This turns out to be quite a bit more tricky than you’d think.