2020-11-26 16:48:27

by Florent Revest

[permalink] [raw]
Subject: [PATCH bpf-next v3 6/6] bpf: Test bpf_sk_storage_get in tcp iterators

This extends the existing bpf_sk_storage_get test where a socket is
created and tagged with its creator's pid by a task_file iterator.

A TCP iterator is now also used at the end of the test to negate the
values already stored in the local storage. The test therefore expects
-getpid() to be stored in the local storage.

Signed-off-by: Florent Revest <[email protected]>
---
.../selftests/bpf/prog_tests/bpf_iter.c | 13 +++++++++++++
.../progs/bpf_iter_bpf_sk_storage_helpers.c | 18 ++++++++++++++++++
2 files changed, 31 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
index 9336d0f18331..b8362147c9e3 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
@@ -978,6 +978,8 @@ static void test_bpf_sk_storage_delete(void)
/* This creates a socket and its local storage. It then runs a task_iter BPF
* program that replaces the existing socket local storage with the tgid of the
* only task owning a file descriptor to this socket, this process, prog_tests.
+ * It then runs a tcp socket iterator that negates the value in the existing
+ * socket local storage, the test verifies that the resulting value is -pid.
*/
static void test_bpf_sk_storage_get(void)
{
@@ -994,6 +996,10 @@ static void test_bpf_sk_storage_get(void)
if (CHECK(sock_fd < 0, "socket", "errno: %d\n", errno))
goto out;

+ err = listen(sock_fd, 1);
+ if (CHECK(err != 0, "listen", "errno: %d\n", errno))
+ goto out;
+
map_fd = bpf_map__fd(skel->maps.sk_stg_map);

err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST);
@@ -1007,6 +1013,13 @@ static void test_bpf_sk_storage_get(void)
"map value wasn't set correctly (expected %d, got %d, err=%d)\n",
getpid(), val, err);

+ do_dummy_read(skel->progs.negate_socket_local_storage);
+
+ err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
+ CHECK(err || val != -getpid(), "bpf_map_lookup_elem",
+ "map value wasn't set correctly (expected %d, got %d, err=%d)\n",
+ -getpid(), val, err);
+
close_socket:
close(sock_fd);
out:
diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c
index d7a7a802d172..b3f0cb139c55 100644
--- a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c
@@ -46,3 +46,21 @@ int fill_socket_owner(struct bpf_iter__task_file *ctx)
return 0;
}

+SEC("iter/tcp")
+int negate_socket_local_storage(struct bpf_iter__tcp *ctx)
+{
+ struct sock_common *sk_common = ctx->sk_common;
+ int *sock_tgid;
+
+ if (!sk_common)
+ return 0;
+
+ sock_tgid = bpf_sk_storage_get(&sk_stg_map, sk_common, 0, 0);
+ if (!sock_tgid)
+ return 0;
+
+ *sock_tgid = -*sock_tgid;
+
+ return 0;
+}
+
--
2.29.2.454.gaff20da3a2-goog


2020-11-27 08:52:21

by Yonghong Song

[permalink] [raw]
Subject: Re: [PATCH bpf-next v3 6/6] bpf: Test bpf_sk_storage_get in tcp iterators



On 11/26/20 8:44 AM, Florent Revest wrote:
> This extends the existing bpf_sk_storage_get test where a socket is
> created and tagged with its creator's pid by a task_file iterator.
>
> A TCP iterator is now also used at the end of the test to negate the
> values already stored in the local storage. The test therefore expects
> -getpid() to be stored in the local storage.
>
> Signed-off-by: Florent Revest <[email protected]>

Ack with a minor comment below.

Acked-by: Yonghong Song <[email protected]>

> ---
> .../selftests/bpf/prog_tests/bpf_iter.c | 13 +++++++++++++
> .../progs/bpf_iter_bpf_sk_storage_helpers.c | 18 ++++++++++++++++++
> 2 files changed, 31 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
> index 9336d0f18331..b8362147c9e3 100644
> --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
> +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
> @@ -978,6 +978,8 @@ static void test_bpf_sk_storage_delete(void)
> /* This creates a socket and its local storage. It then runs a task_iter BPF
> * program that replaces the existing socket local storage with the tgid of the
> * only task owning a file descriptor to this socket, this process, prog_tests.
> + * It then runs a tcp socket iterator that negates the value in the existing
> + * socket local storage, the test verifies that the resulting value is -pid.
> */
> static void test_bpf_sk_storage_get(void)
> {
> @@ -994,6 +996,10 @@ static void test_bpf_sk_storage_get(void)
> if (CHECK(sock_fd < 0, "socket", "errno: %d\n", errno))
> goto out;
>
> + err = listen(sock_fd, 1);
> + if (CHECK(err != 0, "listen", "errno: %d\n", errno))
> + goto out;
> +
> map_fd = bpf_map__fd(skel->maps.sk_stg_map);
>
> err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST);
> @@ -1007,6 +1013,13 @@ static void test_bpf_sk_storage_get(void)
> "map value wasn't set correctly (expected %d, got %d, err=%d)\n",
> getpid(), val, err);
>
> + do_dummy_read(skel->progs.negate_socket_local_storage);
> +
> + err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
> + CHECK(err || val != -getpid(), "bpf_map_lookup_elem",
> + "map value wasn't set correctly (expected %d, got %d, err=%d)\n",
> + -getpid(), val, err);
> +
> close_socket:
> close(sock_fd);
> out:
> diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c
> index d7a7a802d172..b3f0cb139c55 100644
> --- a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c
> +++ b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_helpers.c
> @@ -46,3 +46,21 @@ int fill_socket_owner(struct bpf_iter__task_file *ctx)
> return 0;
> }
>
> +SEC("iter/tcp")
> +int negate_socket_local_storage(struct bpf_iter__tcp *ctx)
> +{
> + struct sock_common *sk_common = ctx->sk_common;
> + int *sock_tgid;
> +
> + if (!sk_common)
> + return 0;
> +
> + sock_tgid = bpf_sk_storage_get(&sk_stg_map, sk_common, 0, 0);
> + if (!sock_tgid)
> + return 0;
> +
> + *sock_tgid = -*sock_tgid;
> +
> + return 0;
> +}
> +

extra empty line here.

>