Extend cgroup_mprog_opts selftests to verify that BPF_PROG_QUERY reports BPF_F_PREORDER in prog_attach_flags for both direct program and link attachments.
Verify that: - Programs attached with BPF_F_PREORDER report BPF_F_ALLOW_MULTI | BPF_F_PREORDER (0x42) in prog_attach_flags. - Programs attached without BPF_F_PREORDER report BPF_F_ALLOW_MULTI (0x2). - Transient flags such as BPF_F_AFTER or BPF_F_LINK are not present in prog_attach_flags. Signed-off-by: Hui Su <[email protected]> --- Notes (bpf-preorder-v3-20260922-check): Testing: - PASS: ./test_progs -t cgroup_preorder (x86_64 QEMU/KVM). - Result reused after a content-equivalent rebase; the patch diff is unchanged. .../bpf/prog_tests/cgroup_mprog_opts.c | 71 ++++++++++++++++++- 1 file changed, 69 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_mprog_opts.c b/tools/testing/selftests/bpf/prog_tests/cgroup_mprog_opts.c index bb60704a3ef9..9ec5e4f96312 100644 --- a/tools/testing/selftests/bpf/prog_tests/cgroup_mprog_opts.c +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_mprog_opts.c @@ -273,11 +273,64 @@ static void test_link_attach_detach(int atype) close(cg); } +static int find_prog_attach_flags(const struct bpf_prog_query_opts *opts, + __u32 prog_id, __u32 *flags) +{ + __u32 i; + + for (i = 0; i < opts->count; i++) { + if (opts->prog_ids[i] == prog_id) { + *flags = opts->prog_attach_flags[i]; + return 0; + } + } + return -ENOENT; +} + +static void assert_preorder_query_flags(int cg, int atype, + __u32 id1, __u32 id2, + __u32 id3, __u32 id4) +{ + LIBBPF_OPTS(bpf_prog_query_opts, optq); + __u32 prog_attach_flags[10] = {}; + __u32 prog_ids[10] = {}; + __u32 flags; + int err; + + optq.prog_ids = prog_ids; + optq.prog_attach_flags = prog_attach_flags; + optq.count = 10; + err = bpf_prog_query_opts(cg, atype, &optq); + if (!ASSERT_OK(err, "prog_query")) + return; + + ASSERT_EQ(optq.count, 4, "count"); + + /* Match by prog_id to avoid relying on query order. */ + err = find_prog_attach_flags(&optq, id1, &flags); + if (ASSERT_OK(err, "find id1")) + ASSERT_EQ(flags, BPF_F_ALLOW_MULTI, "flags id1"); + + err = find_prog_attach_flags(&optq, id2, &flags); + if (ASSERT_OK(err, "find id2")) + ASSERT_EQ(flags, BPF_F_ALLOW_MULTI | BPF_F_PREORDER, + "flags id2"); + + err = find_prog_attach_flags(&optq, id3, &flags); + if (ASSERT_OK(err, "find id3")) + ASSERT_EQ(flags, BPF_F_ALLOW_MULTI | BPF_F_PREORDER, + "flags id3"); + + err = find_prog_attach_flags(&optq, id4, &flags); + if (ASSERT_OK(err, "find id4")) + ASSERT_EQ(flags, BPF_F_ALLOW_MULTI, "flags id4"); +} + static void test_preorder_prog_attach_detach(int atype) { LIBBPF_OPTS(bpf_prog_attach_opts, opta); LIBBPF_OPTS(bpf_prog_detach_opts, optd); - __u32 fd1, fd2, fd3, fd4; + __u32 fd1, fd2, fd3, fd4, id1, id2, id3, id4; struct cgroup_mprog *skel; int cg, err; @@ -294,6 +347,11 @@ static void test_preorder_prog_attach_detach(int atype) fd3 = bpf_program__fd(skel->progs.getsockopt_3); fd4 = bpf_program__fd(skel->progs.getsockopt_4); + id1 = id_from_prog_fd(fd1); + id2 = id_from_prog_fd(fd2); + id3 = id_from_prog_fd(fd3); + id4 = id_from_prog_fd(fd4); + assert_mprog_count(cg, atype, 0); LIBBPF_OPTS_RESET(opta, @@ -357,6 +415,8 @@ static void test_preorder_prog_attach_detach(int atype) assert_mprog_count(cg, atype, 4); + assert_preorder_query_flags(cg, atype, id1, id2, id3, id4); + err = bpf_prog_detach_opts(fd4, cg, atype, &optd); ASSERT_OK(err, "prog_detach"); assert_mprog_count(cg, atype, 3); @@ -386,7 +446,7 @@ static void test_preorder_link_attach_detach(int atype) LIBBPF_OPTS(bpf_cgroup_opts, opta); struct bpf_link *link1, *link2, *link3, *link4; struct cgroup_mprog *skel; - __u32 fd2; + __u32 fd2, id1, id2, id3, id4; int cg; cg = test__join_cgroup("/preorder_link_attach_detach"); @@ -399,6 +459,11 @@ static void test_preorder_link_attach_detach(int atype) fd2 = bpf_program__fd(skel->progs.getsockopt_2); + id1 = id_from_prog_fd(bpf_program__fd(skel->progs.getsockopt_1)); + id2 = id_from_prog_fd(fd2); + id3 = id_from_prog_fd(bpf_program__fd(skel->progs.getsockopt_3)); + id4 = id_from_prog_fd(bpf_program__fd(skel->progs.getsockopt_4)); + assert_mprog_count(cg, atype, 0); LIBBPF_OPTS_RESET(opta, @@ -460,6 +525,8 @@ static void test_preorder_link_attach_detach(int atype) assert_mprog_count(cg, atype, 4); + assert_preorder_query_flags(cg, atype, id1, id2, id3, id4); + bpf_link__destroy(link4); assert_mprog_count(cg, atype, 3); -- 2.55.0

