> On Dec 19, 2022, at 10:25 AM, sdf@xxxxxxxxxx wrote:
>
> On 12/17, Aditi Ghag wrote:
>> The test cases for TCP and UDP mirror the
>> intended usages of the helper.
>
>> As the helper destroys sockets asynchronously,
>> the tests have sleep invocation before validating
>> if the sockets were destroyed by sending data.
>
>> Also, while all the protocol specific helpers
>> set `ECONNABORTED` error code on the destroyed sockets,
>> only the TCP test case has the validation check. UDP
>> sockets have an overriding error code from the disconnect
>> call during abort.
>
>> Signed-off-by: Aditi Ghag <aditi.ghag@xxxxxxxxxxxxx>
>> ---
>> .../selftests/bpf/prog_tests/sock_destroy.c | 131 ++++++++++++++++++
>> .../selftests/bpf/progs/sock_destroy_prog.c | 96 +++++++++++++
>> 2 files changed, 227 insertions(+)
>> create mode 100644 tools/testing/selftests/bpf/prog_tests/sock_destroy.c
>> create mode 100644 tools/testing/selftests/bpf/progs/sock_destroy_prog.c
>
>> diff --git a/tools/testing/selftests/bpf/prog_tests/sock_destroy.c b/tools/testing/selftests/bpf/prog_tests/sock_destroy.c
>> new file mode 100644
>> index 000000000000..b920f4501809
>> --- /dev/null
>> +++ b/tools/testing/selftests/bpf/prog_tests/sock_destroy.c
>> @@ -0,0 +1,131 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +#include <test_progs.h>
>> +
>> +#include "sock_destroy_prog.skel.h"
>> +#include "network_helpers.h"
>> +
>> +#define ECONNABORTED 103
>> +
>> +static int duration;
>> +
>> +static void start_iter_sockets(struct bpf_program *prog)
>> +{
>> + struct bpf_link *link;
>> + char buf[16] = {};
>> + int iter_fd, len;
>> +
>> + link = bpf_program__attach_iter(prog, NULL);
>> + if (!ASSERT_OK_PTR(link, "attach_iter"))
>> + return;
>> +
>> + iter_fd = bpf_iter_create(bpf_link__fd(link));
>> + if (!ASSERT_GE(iter_fd, 0, "create_iter"))
>> + goto free_link;
>> +
>> + while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
>> + ;
>> + CHECK(len < 0, "read", "read failed: %s\n", strerror(errno));
>
> CHECK(s) are not super appealing in the new code, can you replace them
> all with ASSERT(s) ? This should also let you drop 'duration' variable.
Sorry, I missed this comment. I can look into replacing CHECK(s) with ASSERT(s)
as a follow-up. Will wait for reviews on patch v2 for now.
>
>> +
>> + close(iter_fd);
>> +
>> +free_link:
>> + bpf_link__destroy(link);
>> +}
>> +
>> +void test_tcp(struct sock_destroy_prog *skel)
>> +{
>> + int serv = -1, clien = -1, n = 0;
>> +
>> + serv = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
>> + if (CHECK(serv < 0, "start_server", "failed to start server\n"))
>> + goto cleanup_serv;
>> +
>> + clien = connect_to_fd(serv, 0);
>> + if (CHECK(clien < 0, "connect_to_fd", "errno %d\n", errno))
>> + goto cleanup_serv;
>> +
>> + serv = accept(serv, NULL, NULL);
>> + if (CHECK(serv < 0, "accept", "errno %d\n", errno))
>> + goto cleanup;
>> +
>> + n = send(clien, "t", 1, 0);
>> + if (CHECK(n < 0, "client_send", "client failed to send on socket\n"))
>> + goto cleanup;
>> +
>> + start_iter_sockets(skel->progs.iter_tcp6);
>> +
>> + // Sockets are destroyed asynchronously.
>> + usleep(1000);
>> + n = send(clien, "t", 1, 0);
>
> That's racy. Do some kind of:
> while (retries--) {
> usleep(100);
> n = send (...)
> if (n < 0)
> break;
> }
> ASSERT_LT(n, 0);
> ASSERT_EQ(errno, ECONNABORTED);
This isn't applicable anymore as sockets are destroyed synchronously in the latest patches.
>
>> +
>> + if (CHECK(n > 0, "client_send", "succeeded on destroyed socket\n"))
>> + goto cleanup;
>> + CHECK(errno != ECONNABORTED, "client_send", "unexpected error code on destroyed socket\n");
>> +
>> +
>> +cleanup:
>> + close(clien);
>> +cleanup_serv:
>> + close(serv);
>> +}
>> +
>> +
>> +void test_udp(struct sock_destroy_prog *skel)
>> +{
>> + int serv = -1, clien = -1, n = 0;
>> +
>> + serv = start_server(AF_INET6, SOCK_DGRAM, NULL, 0, 0);
>> + if (CHECK(serv < 0, "start_server", "failed to start server\n"))
>> + goto cleanup_serv;
>> +
>> + clien = connect_to_fd(serv, 0);
>> + if (CHECK(clien < 0, "connect_to_fd", "errno %d\n", errno))
>> + goto cleanup_serv;
>> +
>> + n = send(clien, "t", 1, 0);
>> + if (CHECK(n < 0, "client_send", "client failed to send on socket\n"))
>> + goto cleanup;
>> +
>> + start_iter_sockets(skel->progs.iter_udp6);
>> +
>> + // Sockets are destroyed asynchronously.
>> + usleep(1000);
>
> Same here.
>
>> +
>> + n = send(clien, "t", 1, 0);
>> + if (CHECK(n > 0, "client_send", "succeeded on destroyed socket\n"))
>> + goto cleanup;
>> + // UDP sockets have an overriding error code after they are disconnected.
>> +
>> +
>> +cleanup:
>> + close(clien);
>> +cleanup_serv:
>> + close(serv);
>> +}
>> +
>> +void test_sock_destroy(void)
>> +{
>> + int cgroup_fd = 0;
>> + struct sock_destroy_prog *skel;
>> +
>> + skel = sock_destroy_prog__open_and_load();
>> + if (!ASSERT_OK_PTR(skel, "skel_open"))
>> + return;
>> +
>> + cgroup_fd = test__join_cgroup("/sock_destroy");
>> + if (CHECK(cgroup_fd < 0, "join_cgroup", "cgroup creation failed\n"))
>> + goto close_cgroup_fd;
>> +
>> + skel->links.sock_connect = bpf_program__attach_cgroup(
>> + skel->progs.sock_connect, cgroup_fd);
>> + if (!ASSERT_OK_PTR(skel->links.sock_connect, "prog_attach"))
>> + goto close_cgroup_fd;
>> +
>> + test_tcp(skel);
>> + test_udp(skel);
>> +
>> +
>> +close_cgroup_fd:
>> + close(cgroup_fd);
>> + sock_destroy_prog__destroy(skel);
>> +}
>> diff --git a/tools/testing/selftests/bpf/progs/sock_destroy_prog.c b/tools/testing/selftests/bpf/progs/sock_destroy_prog.c
>> new file mode 100644
>> index 000000000000..ec566033f41f
>> --- /dev/null
>> +++ b/tools/testing/selftests/bpf/progs/sock_destroy_prog.c
>> @@ -0,0 +1,96 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +
>> +#include "vmlinux.h"
>> +
>> +#include <bpf/bpf_helpers.h>
>> +
>> +#define AF_INET6 10
>> +
>> +struct {
>> + __uint(type, BPF_MAP_TYPE_ARRAY);
>> + __uint(max_entries, 1);
>> + __type(key, __u32);
>> + __type(value, __u64);
>> +} tcp_conn_sockets SEC(".maps");
>> +
>> +struct {
>> + __uint(type, BPF_MAP_TYPE_ARRAY);
>> + __uint(max_entries, 1);
>> + __type(key, __u32);
>> + __type(value, __u64);
>> +} udp_conn_sockets SEC(".maps");
>> +
>> +SEC("cgroup/connect6")
>> +int sock_connect(struct bpf_sock_addr *ctx)
>> +{
>> + int key = 0;
>> + __u64 sock_cookie = 0;
>> + __u32 keyc = 0;
>> +
>> + if (ctx->family != AF_INET6 || ctx->user_family != AF_INET6)
>> + return 1;
>> +
>> + sock_cookie = bpf_get_socket_cookie(ctx);
>> + if (ctx->protocol == IPPROTO_TCP)
>> + bpf_map_update_elem(&tcp_conn_sockets, &key, &sock_cookie, 0);
>> + else if (ctx->protocol == IPPROTO_UDP)
>> + bpf_map_update_elem(&udp_conn_sockets, &keyc, &sock_cookie, 0);
>> + else
>> + return 1;
>> +
>> + return 1;
>> +}
>> +
>> +SEC("iter/tcp")
>> +int iter_tcp6(struct bpf_iter__tcp *ctx)
>> +{
>> + struct sock_common *sk_common = ctx->sk_common;
>> + struct seq_file *seq = ctx->meta->seq;
>> + __u64 sock_cookie = 0;
>> + __u64 *val;
>> + int key = 0;
>> +
>> + if (!sk_common)
>> + return 0;
>> +
>> + if (sk_common->skc_family != AF_INET6)
>> + return 0;
>> +
>> + sock_cookie = bpf_get_socket_cookie(sk_common);
>> + val = bpf_map_lookup_elem(&tcp_conn_sockets, &key);
>> +
>> + if (!val)
>> + return 0;
>> +
>> + if (sock_cookie == *val)
>> + bpf_sock_destroy(sk_common);
>> +
>> + return 0;
>> +}
>> +
>> +SEC("iter/udp")
>> +int iter_udp6(struct bpf_iter__udp *ctx)
>> +{
>> + struct seq_file *seq = ctx->meta->seq;
>> + struct udp_sock *udp_sk = ctx->udp_sk;
>> + struct sock *sk = (struct sock *) udp_sk;
>> + __u64 sock_cookie = 0;
>> + int key = 0;
>> + __u64 *val;
>> +
>> + if (!sk)
>> + return 0;
>> +
>> + sock_cookie = bpf_get_socket_cookie(sk);
>> + val = bpf_map_lookup_elem(&udp_conn_sockets, &key);
>> +
>> + if (!val)
>> + return 0;
>> +
>> + if (sock_cookie == *val)
>> + bpf_sock_destroy(sk);
>> +
>> + return 0;
>> +}
>> +
>> +char _license[] SEC("license") = "GPL";
>> --
>> 2.34.1
