Re: [PATCH v3 4/4] samples: Add example of using pidfd getfd in conjunction with user trap

From: Christian Brauner
Date: Mon Dec 16 2019 - 21:07:28 EST


On Tue, Dec 17, 2019 at 01:00:27AM +0000, Sargun Dhillon wrote:
> This sample adds the usage of SECCOMP_RET_USER_NOTIF together with pidfd
> GETFD ioctl. It shows trapping a syscall, and handling it by extracting
> the FD into the parent process without stopping the child process.
> Although, in this example, there's no explicit policy separation in
> the two processes, it can be generalized into the example of a transparent
> proxy.
>
> Signed-off-by: Sargun Dhillon <sargun@xxxxxxxxx>
> ---
> samples/seccomp/.gitignore | 1 +
> samples/seccomp/Makefile | 9 +-
> samples/seccomp/user-trap-pidfd.c | 190 ++++++++++++++++++++++++++++++

This is a great sample.
Could you please also add tests without seccomp to the pidfd-testsuite
itself under tools/testing/selftests/pidfd. I want to have all pidfd
features tested in one place so that people don't need to run
seccomp-bpf, or compile the optional samples but can just run the pidfd
test-suite and it'll bang on all features.

Christian