On 8/6/24 12:55 AM, Alexis Lothoré (eBPF Foundation) wrote:
diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_ancestor.c
b/tools/testing/selftests/bpf/prog_tests/cgroup_ancestor.c
new file mode 100644
index 000000000000..4e41463533c0
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/cgroup_ancestor.c
@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "test_progs.h"
+#include "network_helpers.h"
+#include "cgroup_helpers.h"
+#include "cgroup_ancestor.skel.h"
+
+#define VETH_PREFIX "test_cgid_"
+#define VETH_1 VETH_PREFIX "1"
+#define VETH_2 VETH_PREFIX "2"
+#define CGROUP_PATH "/skb_cgroup_test"
+#define NUM_CGROUP_LEVELS 4
+#define WAIT_AUTO_IP_MAX_ATTEMPT 10
+#define DST_ADDR "ff02::1"
+#define DST_PORT 1234
+#define MAX_ASSERT_NAME 32
+
+struct test_data {
+ struct cgroup_ancestor *skel;
+ struct bpf_tc_hook qdisc;
+ struct bpf_tc_opts tc_attach;
+};
+
+static int send_datagram(void)
+{
+ unsigned char buf[] = "some random test data";
+ struct sockaddr_in6 addr = { .sin6_family = AF_INET6,
+ .sin6_port = htons(DST_PORT),
+ .sin6_scope_id = if_nametoindex(VETH_1) };
+ int sock, n;
+
+ if (!ASSERT_EQ(inet_pton(AF_INET6, DST_ADDR, &addr.sin6_addr), 1,
+ "inet_pton"))
+ return -1;
+
+ sock = socket(AF_INET6, SOCK_DGRAM, 0);
sock is leaked.
+ if (!ASSERT_OK_FD(sock, "create socket"))
+ return sock;
+
+ n = sendto(sock, buf, sizeof(buf), 0, (const struct sockaddr *)&addr,
+ sizeof(addr));
+ if (!ASSERT_EQ(n, sizeof(buf), "send data"))
+ return n;
+
+ return 0;
+}
+
+static int wait_local_ip(void)
+{
+ char *ping_cmd = ping_command(AF_INET6);
+ int i, err;
+
+ for (i = 0; i < WAIT_AUTO_IP_MAX_ATTEMPT; i++) {
+ err = SYS_NOFAIL("%s -c 1 -W 1 %s%%%s", ping_cmd, DST_ADDR,
+ VETH_1);
+ if (!err)
+ break;
+ }
+
+ return err;
+}
+
+static int setup_network(struct test_data *t)
+{
+ int ret;
+
+ SYS(fail, "ip link add dev %s type veth peer name %s", VETH_1, VETH_2);
+ SYS(fail, "ip link set %s up", VETH_1);
+ SYS(fail, "ip link set %s up", VETH_2);
Same. Do it under a new netns.
+
+ ret = wait_local_ip();
+ if (!ASSERT_EQ(ret, 0, "wait local ip"))
+ goto fail;
+
+ memset(&t->qdisc, 0, sizeof(t->qdisc));
+ t->qdisc.sz = sizeof(t->qdisc);
+ t->qdisc.attach_point = BPF_TC_EGRESS;
+ t->qdisc.ifindex = if_nametoindex(VETH_1);
+ if (!ASSERT_NEQ(t->qdisc.ifindex, 0, "if_nametoindex"))
+ goto cleanup_interfaces;
+ if (!ASSERT_OK(bpf_tc_hook_create(&t->qdisc), "qdisc add"))
+ goto cleanup_interfaces;
+
+ memset(&t->tc_attach, 0, sizeof(t->tc_attach));
+ t->tc_attach.sz = sizeof(t->tc_attach);
+ t->tc_attach.prog_fd = bpf_program__fd(t->skel->progs.log_cgroup_id);
+ if (!ASSERT_OK(bpf_tc_attach(&t->qdisc, &t->tc_attach), "filter add"))
+ goto cleanup_qdisc;
+
+ return 0;
+
+cleanup_qdisc:
+ bpf_tc_hook_destroy(&t->qdisc);
+cleanup_interfaces:
+ SYS_NOFAIL("ip link del %s", VETH_1);
+fail:
+ return 1;
+}
+
+static void cleanup_network(struct test_data *t)
+{
+ bpf_tc_detach(&t->qdisc, &t->tc_attach);
+ bpf_tc_hook_destroy(&t->qdisc);
+ /* Deleting first interface will also delete peer interface */
+ SYS_NOFAIL("ip link del %s", VETH_1);
+}
+
+static void check_ancestors_ids(struct test_data *t)
+{
+ __u64 expected_ids[NUM_CGROUP_LEVELS];
+ char assert_name[MAX_ASSERT_NAME];
+ __u32 level;
+
+ expected_ids[0] = get_cgroup_id("/.."); /* root cgroup */
+ expected_ids[1] = get_cgroup_id("");
+ expected_ids[2] = get_cgroup_id(CGROUP_PATH);
+ expected_ids[3] = 0; /* non-existent cgroup */
+
+ for (level = 0; level < NUM_CGROUP_LEVELS; level++) {
+ snprintf(assert_name, MAX_ASSERT_NAME,
+ "ancestor id at level %d", level);
+ ASSERT_EQ(t->skel->bss->cgroup_ids[level], expected_ids[level],
+ assert_name);
+ }
+}
+
+void test_cgroup_ancestor(void)
+{
+ struct test_data t;
+ int cgroup_fd;
+
+ t.skel = cgroup_ancestor__open_and_load();
+ if (!ASSERT_OK_PTR(t.skel, "open and load"))
+ return;
+
+ if (setup_network(&t))
+ goto cleanup_progs;
+
+ cgroup_fd = cgroup_setup_and_join(CGROUP_PATH);
cgroup_fd is leaked.
Thanks for working on this.
+ if (cgroup_fd < 0)
+ goto cleanup_network;
+
+ if (send_datagram())
+ goto cleanup_cgroups;
+
+ check_ancestors_ids(&t);
+
+cleanup_cgroups:
+ cleanup_cgroup_environment();
+cleanup_network:
+ cleanup_network(&t);
+cleanup_progs:
+ cgroup_ancestor__destroy(t.skel);
+}
