Re: [RFC bpf-next 2/2] selftests/bpf: Add uprobe multi fail test

[Jiri Olsa <olsajiri@gmail.com>]

On Wed, Dec 13, 2023 at 06:08:54PM +0000, Alan Maguire wrote:
> On 13/12/2023 14:12, Jiri Olsa wrote:
> > We fail to create uprobe if we pass negative offset,
> > adding test for that.
> > 
> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> 
> Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
> 
> small suggestion below..
> 
> > ---
> >  .../bpf/prog_tests/uprobe_multi_test.c        | 27 +++++++++++++++++++
> >  1 file changed, 27 insertions(+)
> > 
> > diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
> > index ece260cf2c0b..aebfa7e6bfd6 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
> > +++ b/tools/testing/selftests/bpf/prog_tests/uprobe_multi_test.c
> > @@ -326,6 +326,31 @@ void test_link_api(void)
> >  	__test_link_api(child);
> >  }
> >  
> > +static void test_attach_api_fails(void)
> > +{
> > +	LIBBPF_OPTS(bpf_link_create_opts, opts);
> > +	const char *path = "/proc/self/exe";
> > +	struct uprobe_multi *skel = NULL;
> > +	int prog_fd, link_fd;
> > +	long offset = -1;
> > +
> > +	skel = uprobe_multi__open_and_load();
> > +	if (!ASSERT_OK_PTR(skel, "uprobe_multi__open_and_load"))
> > +		return;
> > +
> > +	/* fail_1 - attach on negative offset */
> > +	opts.uprobe_multi.path = path;
> > +	opts.uprobe_multi.offsets = (unsigned long *) &offset;
> > +	opts.uprobe_multi.cnt = 1;
> > +
> > +	prog_fd = bpf_program__fd(skel->progs.uprobe_extra);
> > +	link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_UPROBE_MULTI, &opts);
> > +	if (!ASSERT_EQ(link_fd, -EINVAL, "link_fd"))
> > +		close(link_fd);
> > +
> 
> would it be worth exercising a few additional error cases here? not
> specifying offsets/cnt triggers an EINVAL too.

yes, I think we can add more tests in here, will check

thanks,
jirka