Compiled bpfilter doesn't load: No such file or directory

[Haxverse]

Hello @qdeslandes,

I have just compiled the bpfilter module on both the linux-6.1.14 branch and the bpf-next branch, both times I get the following output in dmesg:

[    4.619942] bpfilter: Loaded bpfilter_umh pid 971
[    4.622811] bpfilter: generate forward packet assessment
[    4.622823] bpfilter: generate forward packet assessment
[    4.625250] bpfilter: failed to create TC hook: No such file or directory
[    4.625348] bpfilter: failed to load chain INPUT in table filter: processed 73 insns (limit 1000000) max_states_per_insn 0 total_states 4 peak_states 4 mark_read 3
[    4.625455] bpfilter: failed to install new table 'filter': No such file or directory
[    4.625578] bpfilter: failed to created filter table: No such file or directory
[    4.625807] bpfilter: read fail 0

Would you happen to know if I did something wrong?

Thanks a lot,
Mr. Hax

[qdeslandes]

Hi!

I tried bpfilter on latest bpf-next changes, and everything is fine on my side:

[  935.679528] bpfilter: Loaded bpfilter_umh pid 10526
[  935.680291] bpfilter: log file opened and ready to use
[  935.680393] bpfilter: generate forward packet assessment
[  935.680422] bpfilter: fixup counter for rule 0
[  935.680451] bpfilter: generate forward packet assessment
[  935.680473] bpfilter: fixup counter for rule 1
[  935.680502] bpfilter: fixup counter for rule 2
[  935.680921] bpfilter: opened BPF map with FD 3
[  935.682306] libbpf: Kernel error message: Exclusivity flag on, cannot modify
[  935.683390] libbpf: Kernel error message: Exclusivity flag on, cannot modify
[  935.684148] libbpf: Kernel error message: Exclusivity flag on, cannot modify
[  935.684190] bpfilter: installed filter table

My guess is that this error is commit from a missing configuration. Could you share your .config file?

Also, I've pushed a few new commits to fix a couple of issues I found out, although I don't expect those to solve your problem.

[Haxverse]

Hello,

That's weird, alright. I personally think the ifindex is part of the problem, anyway, here's my current .config file: https://pastebin.com/raw/RKN6RgPJ

Thanks a lot,
Mr. Hax

[qdeslandes]

I personally think the ifindex is part of the problem

Seems like it. I added a comment to README.md to explain how to modify the interface index. Feel free to try it! :)

[qdeslandes]

@Haxverse did changing the ifindex solved it?

[qdeslandes]

Closing this issue as it is most likely fixed now.