Support SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV

[AkihiroSuda]

SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV was added in the Spec v1.1.0-rc.1:

• seccomp: Add flag SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV runtime-spec#1161

[kolyshkin]

The commit seccomp/libseccomp#391 is not in the released version yet, and thus there's no support in libseccomp-golang either.

[Zheaoli]

I think maybe we have two issues to solve before supporting SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV

1. libsescomp need a stable release
2. How to test the SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV?

[Zheaoli]

About the test, I may have some ideas.

1. we may need a new binary for SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV in contrib/cmd/, like old seccompagent
2. we can listen to UDS to reach the listener fd. And we should add a new signal handler for SIGUSR1
3. In the bash test, we can run the runc binary with SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV like other secomp tests.
4. We send a SIGUSR1 for the runc process. We can check if this process is in the D state.
5. We send a SIGUSR1 to the new sescomp agent, the agent will make a response for SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV. And the runc process would exits.
6. We can check if the process exits correctly.

cc @utam0k

[AkihiroSuda]

I guess we can have a CI job to run the test with the main branch of libseccomp.
Ideally we should wait for libseccomp v2.6 GA, but it doesn't seem planned soon.

[Zheaoli]

Ideally we should wait for libseccomp v2.6 GA, but it doesn't seem planned soon.

Yeah.... I will submit a issue to ask for the release plan