Hi! What started with the simple observation that bpf_dispatcher_*_func() was broken for calling CFI functions with a __nocfi calling context for FineIBT ended up with a complete BPF wide CFI fixup. With these changes on the BPF selftest suite passes without crashing -- there's still a few failures, but Alexei has graciously offered to look into those. (Alexei, I have presumed your SoB on the very last patch, please update as you see fit) Changes since v2 are numerous but include: - cfi_get_offset() -- as a means to communicate the offset (ast) - 5 new patches fixing various BPF internals to be CFI clean Note: it *might* be possible to merge the bpf_bpf_tcp_ca.c:unsupported_ops[] thing into the CFI stubs, as is get_info will have a NULL stub, unlike the others. --- arch/riscv/include/asm/cfi.h | 3 +- arch/riscv/kernel/cfi.c | 2 +- arch/x86/include/asm/cfi.h | 126 +++++++++++++++++++++++++++++++++++++- arch/x86/kernel/alternative.c | 87 +++++++++++++++++++++++--- arch/x86/kernel/cfi.c | 4 +- arch/x86/net/bpf_jit_comp.c | 134 +++++++++++++++++++++++++++++++++++------ include/asm-generic/Kbuild | 1 + include/linux/bpf.h | 27 ++++++++- include/linux/cfi.h | 12 ++++ kernel/bpf/bpf_struct_ops.c | 16 ++--- kernel/bpf/core.c | 25 ++++++++ kernel/bpf/cpumask.c | 8 ++- kernel/bpf/helpers.c | 18 +++++- net/bpf/bpf_dummy_struct_ops.c | 31 +++++++++- net/bpf/test_run.c | 15 ++++- net/ipv4/bpf_tcp_ca.c | 69 +++++++++++++++++++++ 16 files changed, 528 insertions(+), 50 deletions(-)
