selftests/bpf: Add more bpf_wq tests

Add bpf_wq selftests to verify:
 * BPF program using non-constant offset of struct bpf_wq is rejected
 * BPF program using map with no BTF for storing struct bpf_wq is rejected

Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20251010164606.147298-2-mykyta.yatsenko5@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/wq.c b/tools/testing/selftests/bpf/prog_tests/wq.c
index 99e438fe12acd527e606b419eca71c66ede59d6f..15c67d23128b24b7eb387b360f766f4b4b88fcf2 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/wq.c
+++ b/tools/testing/selftests/bpf/prog_tests/wq.c
@@ -38,3 +38,59 @@ void serial_test_failures_wq(void)
 {
        RUN_TESTS(wq_failures);
 }
+
+static void test_failure_map_no_btf(void)
+{
+       struct wq *skel = NULL;
+       char log[8192];
+       const struct bpf_insn *insns;
+       size_t insn_cnt;
+       int ret, err, map_fd;
+       LIBBPF_OPTS(bpf_prog_load_opts, opts, .log_size = sizeof(log), .log_buf = log,
+                   .log_level = 2);
+
+       skel = wq__open();
+       if (!ASSERT_OK_PTR(skel, "skel_open"))
+               return;
+
+       err = bpf_object__prepare(skel->obj);
+       if (!ASSERT_OK(err, "skel__prepare"))
+               goto out;
+
+       map_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "map_no_btf", sizeof(__u32), sizeof(__u64), 100,
+                               NULL);
+       if (!ASSERT_GT(map_fd, -1, "map create"))
+               goto out;
+
+       err = bpf_map__reuse_fd(skel->maps.array, map_fd);
+       if (!ASSERT_OK(err, "map reuse fd")) {
+               close(map_fd);
+               goto out;
+       }
+
+       insns = bpf_program__insns(skel->progs.test_map_no_btf);
+       if (!ASSERT_OK_PTR(insns, "insns ptr"))
+               goto out;
+
+       insn_cnt = bpf_program__insn_cnt(skel->progs.test_map_no_btf);
+       if (!ASSERT_GT(insn_cnt, 0u, "insn cnt"))
+               goto out;
+
+       ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts);
+       if (!ASSERT_LT(ret, 0, "prog load failed")) {
+               if (ret > 0)
+                       close(ret);
+               goto out;
+       }
+
+       ASSERT_HAS_SUBSTR(log, "map 'map_no_btf' has to have BTF in order to use bpf_wq",
+                         "log complains no map BTF");
+out:
+       wq__destroy(skel);
+}
+
+void test_wq_custom(void)
+{
+       if (test__start_subtest("test_failure_map_no_btf"))
+               test_failure_map_no_btf();
+}

diff --git a/tools/testing/selftests/bpf/progs/wq.c b/tools/testing/selftests/bpf/progs/wq.c
index 2f1ba08c293e26c48e0866ea00ff73b8517faab3..25be2cd9d42c729cf93cb85a5a0675859570b771 100644 (file)
--- a/tools/testing/selftests/bpf/progs/wq.c
+++ b/tools/testing/selftests/bpf/progs/wq.c
@@ -187,3 +187,20 @@ long test_call_lru_sleepable(void *ctx)
 
        return test_elem_callback(&lru, &key, wq_callback);
 }
+
+SEC("tc")
+long test_map_no_btf(void *ctx)
+{
+       struct elem *val;
+       struct bpf_wq *wq;
+       int key = 42;
+
+       val = bpf_map_lookup_elem(&array, &key);
+       if (!val)
+               return -2;
+
+       wq = &val->w;
+       if (bpf_wq_init(wq, &array, 0) != 0)
+               return -3;
+       return 0;
+}

diff --git a/tools/testing/selftests/bpf/progs/wq_failures.c b/tools/testing/selftests/bpf/progs/wq_failures.c
index 4240211a19001fbbe0860da761121917a91049f5..d06f6d40594a6585f9813f9e54f54022959d391a 100644 (file)
--- a/tools/testing/selftests/bpf/progs/wq_failures.c
+++ b/tools/testing/selftests/bpf/progs/wq_failures.c
@@ -142,3 +142,26 @@ long test_wrong_wq_pointer_offset(void *ctx)
 
        return -22;
 }
+
+SEC("tc")
+__log_level(2)
+__failure
+__msg(": (85) call bpf_wq_init#")
+__msg("R1 doesn't have constant offset. bpf_wq has to be at the constant offset")
+long test_bad_wq_off(void *ctx)
+{
+       struct elem *val;
+       struct bpf_wq *wq;
+       int key = 42;
+       u64 unknown;
+
+       val = bpf_map_lookup_elem(&array, &key);
+       if (!val)
+               return -2;
+
+       unknown = bpf_get_prandom_u32();
+       wq = &val->w + unknown;
+       if (bpf_wq_init(wq, &array, 0) != 0)
+               return -3;
+       return 0;
+}