On Mon, 5 Sept 2022 at 16:34, Roberto Sassu <roberto.sassu@xxxxxxxxxxxxxxx> wrote: > > From: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > > One of the desirable features in security is the ability to restrict import > of data to a given system based on data authenticity. If data import can be > restricted, it would be possible to enforce a system-wide policy based on > the signing keys the system owner trusts. > > This feature is widely used in the kernel. For example, if the restriction > is enabled, kernel modules can be plugged in only if they are signed with a > key whose public part is in the primary or secondary keyring. > > For eBPF, it can be useful as well. For example, it might be useful to > authenticate data an eBPF program makes security decisions on. > > [...] CI is crashing with NULL deref for test_progs-no_alu32 with llvm-16, but I don't think the problem is in this series. This is most likely unrelated to BPF, as the crash happens inside kernel/time/tick-sched.c:tick_nohz_restart_sched_tick. This was the same case in https://lore.kernel.org/bpf/CAP01T74steDfP6O8QOshoto3e3RnHhKtAeTbnrPBZS3YJXjvbA@xxxxxxxxxxxxxx. So, https://github.com/kernel-patches/bpf/runs/8194263557?check_suite_focus=true and https://github.com/kernel-patches/bpf/runs/7982907380?check_suite_focus=true look similar to me, and may not be related to BPF. They only trigger during runs compiled using LLVM 16, so maybe some compiler transformation is surfacing the problem?