Re: [RFCv2 07/16] bpf: enable non-core use of the verfier
From: Jakub Kicinski <hidden>
Date: 2016-08-30 20:22:51
On Tue, 30 Aug 2016 21:07:50 +0200, Daniel Borkmann wrote:
quoted
Having two modes seems more straight forward and I think we would only need to pay attention in the LD_IMM64 case, I don't think I've seen LLVM generating XORs, it's just the cBPF -> eBPF conversion.Okay, though, I think that the cBPF to eBPF migration wouldn't even pass through the bpf_parse() handling, since verifier is not aware on some of their aspects such as emitting calls directly (w/o *proto) or arg mappings. Probably make sense to reject these (bpf_prog_was_classic()) if they cannot be handled anyway?
TBH again I only use cBPF for testing. It's a convenient way of generating certain instruction sequences. I can probably just drop it completely but the XOR patch is just 3 lines of code so not a huge cost either... I'll keep patch 6 in my tree for now. Alternatively - is there any eBPF assembler out there? Something converting verifier output back into ELF would be quite cool.