Re: [PATCH bpf-next v6 7/8] bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM

[KP Singh]

On 25-Mär 19:01, Andrii Nakryiko wrote:
> On Wed, Mar 25, 2020 at 8:27 AM KP Singh <kpsingh@xxxxxxxxxxxx> wrote:
> >
> > From: KP Singh <kpsingh@xxxxxxxxxx>
> >
> > * Load/attach a BPF program that hooks to file_mprotect (int)
> >   and bprm_committed_creds (void).
> > * Perform an action that triggers the hook.
> > * Verify if the audit event was received using the shared global
> >   variables for the process executed.
> > * Verify if the mprotect returns a -EPERM.
> >
> > Signed-off-by: KP Singh <kpsingh@xxxxxxxxxx>
> > Reviewed-by: Brendan Jackman <jackmanb@xxxxxxxxxx>
> > Reviewed-by: Florent Revest <revest@xxxxxxxxxx>
> > Reviewed-by: Thomas Garnier <thgarnie@xxxxxxxxxx>
> > ---
> >  tools/testing/selftests/bpf/config            |  2 +
> >  .../selftests/bpf/prog_tests/test_lsm.c       | 84 +++++++++++++++++++
> >  tools/testing/selftests/bpf/progs/lsm.c       | 48 +++++++++++
> >  3 files changed, 134 insertions(+)
> >  create mode 100644 tools/testing/selftests/bpf/prog_tests/test_lsm.c
> >  create mode 100644 tools/testing/selftests/bpf/progs/lsm.c
> >
> 
> [...]
> 
> > +
> > +int exec_cmd(int *monitored_pid)
> > +{
> > +       int child_pid;
> > +
> > +       child_pid = fork();
> > +       if (child_pid == 0) {
> > +               *monitored_pid = getpid();
> > +               execvp(CMD_ARGS[0], CMD_ARGS);
> > +               return -EINVAL;
> > +       } else if (child_pid > 0)
> 
> This test is part of test_progs, so let's be a good citizen and wait
> for your specific child. I'd rather not hunt for elusive bugs later,
> so please use waitpid() instead.

Good idea. Done.

- KP

> 
> Otherwise looks good and clean, thanks!
> 
> > +               return wait(NULL);
> > +
> > +       return -EINVAL;
> > +}
> > +
> 
> [...]