From a1c05c3b09e0a92b26b94650837bf06c664beb1b Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 14 Apr 2021 21:51:46 +0200 Subject: selftests/bpf: Test that module can't be unloaded with attached trampoline Adding test to verify that once we attach module's trampoline, the module can't be unloaded. Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210414195147.1624932-7-jolsa@kernel.org --- .../selftests/bpf/prog_tests/module_attach.c | 23 ++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/bpf/prog_tests/module_attach.c b/tools/testing/selftests/bpf/prog_tests/module_attach.c index 5bc53d53d86e..d85a69b7ce44 100644 --- a/tools/testing/selftests/bpf/prog_tests/module_attach.c +++ b/tools/testing/selftests/bpf/prog_tests/module_attach.c @@ -45,12 +45,18 @@ static int trigger_module_test_write(int write_sz) return 0; } +static int delete_module(const char *name, int flags) +{ + return syscall(__NR_delete_module, name, flags); +} + void test_module_attach(void) { const int READ_SZ = 456; const int WRITE_SZ = 457; struct test_module_attach* skel; struct test_module_attach__bss *bss; + struct bpf_link *link; int err; skel = test_module_attach__open(); @@ -84,6 +90,23 @@ void test_module_attach(void) ASSERT_EQ(bss->fexit_ret, -EIO, "fexit_tet"); ASSERT_EQ(bss->fmod_ret_read_sz, READ_SZ, "fmod_ret"); + test_module_attach__detach(skel); + + /* attach fentry/fexit and make sure it get's module reference */ + link = bpf_program__attach(skel->progs.handle_fentry); + if (!ASSERT_OK_PTR(link, "attach_fentry")) + goto cleanup; + + ASSERT_ERR(delete_module("bpf_testmod", 0), "delete_module"); + bpf_link__destroy(link); + + link = bpf_program__attach(skel->progs.handle_fexit); + if (!ASSERT_OK_PTR(link, "attach_fexit")) + goto cleanup; + + ASSERT_ERR(delete_module("bpf_testmod", 0), "delete_module"); + bpf_link__destroy(link); + cleanup: test_module_attach__destroy(skel); } -- cgit v1.2.3