disable userfaultfd for all unprivileged users #5167
Merged
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The
userfaultfd
system call (and subsequent API) can be misused making it easier to exploit existing use-after-free (and similar) bugs that might otherwise only make a short window or race condition available.Thus, we here disable it (on the host nodes) for unprivileged users through the global sysctl knob "vm.unprivileged_userfaultfd".
Fixes #5156
Signed-off-by: Leo Di Donato [email protected]