On Wed, Aug 4, 2021 at 5:45 AM Jussi Maki [off-list ref] wrote:

Add a test suite to test XDP bonding implementation
over a pair of veth devices.

Signed-off-by: Jussi Maki <redacted>
---
 .../selftests/bpf/prog_tests/xdp_bonding.c    | 533 ++++++++++++++++++
 1 file changed, 533 insertions(+)

[...]

+
+static int xdp_attach(struct skeletons *skeletons, struct bpf_program *prog, char *iface)
+{
+       struct bpf_link *link;
+       int ifindex;
+
+       ifindex = if_nametoindex(iface);
+       if (!ASSERT_GT(ifindex, 0, "get ifindex"))
+               return -1;
+
+       if (!ASSERT_LE(skeletons->nlinks, MAX_BPF_LINKS, "too many XDP programs attached"))

If it's already less or equal to MAX_BPF_LINKS, then you'll bump
nlinks below one more time and write beyond the array boundaries?

+               return -1;
+
+       link = bpf_program__attach_xdp(prog, ifindex);
+       if (!ASSERT_OK_PTR(link, "attach xdp program"))
+               return -1;
+
+       skeletons->links[skeletons->nlinks++] = link;
+       return 0;
+}
+

[...]

+
+static void bonding_cleanup(struct skeletons *skeletons)
+{
+       restore_root_netns();
+       while (skeletons->nlinks) {
+               skeletons->nlinks--;
+               bpf_link__detach(skeletons->links[skeletons->nlinks]);

You want bpf_link__destroy, not bpf_link__detach (detach will leave
underlying BPF link FD open and ensure that bpf_link__destory() won't
do anything with it, just frees memory).

+       }
+       ASSERT_OK(system("ip link delete bond1"), "delete bond1");
+       ASSERT_OK(system("ip link delete veth1_1"), "delete veth1_1");
+       ASSERT_OK(system("ip link delete veth1_2"), "delete veth1_2");
+       ASSERT_OK(system("ip netns delete ns_dst"), "delete ns_dst");
+}
+

+out:
+       bonding_cleanup(skeletons);
+}
+
+

nit: extra line

+/* Test the broadcast redirection using xdp_redirect_map_multi_prog and adding
+ * all the interfaces to it and checking that broadcasting won't send the packet
+ * to neither the ingress bond device (bond2) or its slave (veth2_1).
+ */
+void test_xdp_bonding_redirect_multi(struct skeletons *skeletons)
+{
+       static const char * const ifaces[] = {"bond2", "veth2_1", "veth2_2"};
+       int veth1_1_rx, veth1_2_rx;
+       int err;
+
+       if (!test__start_subtest("xdp_bonding_redirect_multi"))
+               return;
+
+       if (bonding_setup(skeletons, BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23,
+                         BOND_ONE_NO_ATTACH))
+               goto out;
+
+

nit: another extra empty line, please check if there are more

+       if (!ASSERT_OK(setns_by_name("ns_dst"), "could not set netns to ns_dst"))
+               goto out;
+

[...]

+       /* enslaving with a XDP program loaded fails */
+       link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth);
+       if (!ASSERT_OK_PTR(link, "attach program to veth"))
+               goto out;
+
+       err = system("ip link set veth master bond");
+       if (!ASSERT_NEQ(err, 0, "attaching slave with xdp program expected to fail"))
+               goto out;
+
+       bpf_link__detach(link);

same here and in few more places, you need destroy

+       link = NULL;
+
+       err = system("ip link set veth master bond");
+       if (!ASSERT_OK(err, "set veth master"))
+               goto out;
+
+       /* attaching to slave when master has no program is allowed */
+       link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth);
+       if (!ASSERT_OK_PTR(link, "attach program to slave when enslaved"))
+               goto out;
+
+       /* attaching to master not allowed when slave has program loaded */
+       link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
+       if (!ASSERT_ERR_PTR(link2, "attach program to master when slave has program"))
+               goto out;
+
+       bpf_link__detach(link);
+       link = NULL;
+
+       /* attaching XDP program to master allowed when slave has no program */
+       link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
+       if (!ASSERT_OK_PTR(link, "attach program to master"))
+               goto out;
+
+       /* attaching to slave not allowed when master has program loaded */
+       link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
+       ASSERT_ERR_PTR(link2, "attach program to slave when master has program");
+
+out:
+       if (link)
+               bpf_link__detach(link);
+       if (link2)
+               bpf_link__detach(link2);

bpf_link__destroy() handles NULLs just fine, you don't have to do extra checks

+
+       system("ip link del veth");
+       system("ip link del bond");
+}
+
+static int libbpf_debug_print(enum libbpf_print_level level,
+                             const char *format, va_list args)
+{
+       if (level != LIBBPF_WARN)
+               vprintf(format, args);
+       return 0;
+}
+
+struct bond_test_case {
+       char *name;
+       int mode;
+       int xmit_policy;
+};
+
+static struct bond_test_case bond_test_cases[] = {
+       { "xdp_bonding_roundrobin", BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23, },
+       { "xdp_bonding_activebackup", BOND_MODE_ACTIVEBACKUP, BOND_XMIT_POLICY_LAYER23 },
+
+       { "xdp_bonding_xor_layer2", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER2, },
+       { "xdp_bonding_xor_layer23", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER23, },
+       { "xdp_bonding_xor_layer34", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER34, },
+};
+
+void test_xdp_bonding(void)

this should be the only non-static function in this file, please fix
all the functions above

+{
+       libbpf_print_fn_t old_print_fn;
+       struct skeletons skeletons = {};
+       int i;
+
+       old_print_fn = libbpf_set_print(libbpf_debug_print);
+
+       root_netns_fd = open("/proc/self/ns/net", O_RDONLY);
+       if (!ASSERT_GE(root_netns_fd, 0, "open /proc/self/ns/net"))
+               goto out;
+
+       skeletons.xdp_dummy = xdp_dummy__open_and_load();
+       if (!ASSERT_OK_PTR(skeletons.xdp_dummy, "xdp_dummy__open_and_load"))
+               goto out;
+
+       skeletons.xdp_tx = xdp_tx__open_and_load();
+       if (!ASSERT_OK_PTR(skeletons.xdp_tx, "xdp_tx__open_and_load"))
+               goto out;
+
+       skeletons.xdp_redirect_multi_kern = xdp_redirect_multi_kern__open_and_load();
+       if (!ASSERT_OK_PTR(skeletons.xdp_redirect_multi_kern,
+                          "xdp_redirect_multi_kern__open_and_load"))
+               goto out;
+
+       test_xdp_bonding_attach(&skeletons);

check for errors

+
+       for (i = 0; i < ARRAY_SIZE(bond_test_cases); i++) {
+               struct bond_test_case *test_case = &bond_test_cases[i];
+
+               test_xdp_bonding_with_mode(
+                       &skeletons,
+                       test_case->name,
+                       test_case->mode,
+                       test_case->xmit_policy);
+       }
+
+       test_xdp_bonding_redirect_multi(&skeletons);
+
+out:
+       if (skeletons.xdp_dummy)
+               xdp_dummy__destroy(skeletons.xdp_dummy);
+       if (skeletons.xdp_tx)
+               xdp_tx__destroy(skeletons.xdp_tx);
+       if (skeletons.xdp_redirect_multi_kern)
+               xdp_redirect_multi_kern__destroy(skeletons.xdp_redirect_multi_kern);

similarly, all libbpf destructors handle NULL and error pointers
cleanly, no need for extra ifs

+
+       libbpf_set_print(old_print_fn);
+       if (root_netns_fd)
+               close(root_netns_fd);
+}
--
2.17.1