Add a test which copies a socket from a sockmap into another sockmap or sockhash. This excercises bpf_map_update_elem support from BPF context. Compare the socket cookies from source and destination to ensure that the copy succeeded.
Also check that the verifier rejects map_update from unsafe contexts.
Signed-off-by: Lorenz Bauer lmb@cloudflare.com --- .../selftests/bpf/prog_tests/sockmap_basic.c | 78 +++++++++++++++++++ .../bpf/progs/test_sockmap_invalid_update.c | 23 ++++++ .../selftests/bpf/progs/test_sockmap_update.c | 48 ++++++++++++ 3 files changed, 149 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/test_sockmap_invalid_update.c create mode 100644 tools/testing/selftests/bpf/progs/test_sockmap_update.c
diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c index 96e7b7f84c65..65ce7c289534 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c @@ -4,6 +4,8 @@
#include "test_progs.h" #include "test_skmsg_load_helpers.skel.h" +#include "test_sockmap_update.skel.h" +#include "test_sockmap_invalid_update.skel.h"
#define TCP_REPAIR 19 /* TCP sock is under repair right now */
@@ -101,6 +103,76 @@ static void test_skmsg_helpers(enum bpf_map_type map_type) test_skmsg_load_helpers__destroy(skel); }
+static void test_sockmap_update(enum bpf_map_type map_type) +{ + struct bpf_prog_test_run_attr tattr; + int err, prog, src, dst, duration = 0; + struct test_sockmap_update *skel; + __u64 src_cookie, dst_cookie; + const __u32 zero = 0; + char dummy[14] = {0}; + __s64 sk; + + sk = connected_socket_v4(); + if (CHECK(sk == -1, "connected_socket_v4", "cannot connect\n")) + return; + + skel = test_sockmap_update__open_and_load(); + if (CHECK(!skel, "open_and_load", "cannot load skeleton\n")) { + close(sk); + return; + } + + prog = bpf_program__fd(skel->progs.copy_sock_map); + src = bpf_map__fd(skel->maps.src); + if (map_type == BPF_MAP_TYPE_SOCKMAP) + dst = bpf_map__fd(skel->maps.dst_sock_map); + else + dst = bpf_map__fd(skel->maps.dst_sock_hash); + + err = bpf_map_update_elem(src, &zero, &sk, BPF_NOEXIST); + if (CHECK(err, "update_elem(src)", "errno=%u\n", errno)) + goto out; + + err = bpf_map_lookup_elem(src, &zero, &src_cookie); + if (CHECK(err, "lookup_elem(src, cookie)", "errno=%u\n", errno)) + goto out; + + tattr = (struct bpf_prog_test_run_attr){ + .prog_fd = prog, + .repeat = 1, + .data_in = dummy, + .data_size_in = sizeof(dummy), + }; + + err = bpf_prog_test_run_xattr(&tattr); + if (CHECK_ATTR(err || !tattr.retval, "bpf_prog_test_run", + "errno=%u retval=%u\n", errno, tattr.retval)) + goto out; + + err = bpf_map_lookup_elem(dst, &zero, &dst_cookie); + if (CHECK(err, "lookup_elem(dst, cookie)", "errno=%u\n", errno)) + goto out; + + CHECK(dst_cookie != src_cookie, "cookie mismatch", "%llu != %llu\n", + dst_cookie, src_cookie); + +out: + close(sk); + test_sockmap_update__destroy(skel); +} + +static void test_sockmap_invalid_update(void) +{ + struct test_sockmap_invalid_update *skel; + int duration = 0; + + skel = test_sockmap_invalid_update__open_and_load(); + CHECK(skel, "open_and_load", "verifier accepted map_update\n"); + if (skel) + test_sockmap_invalid_update__destroy(skel); +} + void test_sockmap_basic(void) { if (test__start_subtest("sockmap create_update_free")) @@ -111,4 +183,10 @@ void test_sockmap_basic(void) test_skmsg_helpers(BPF_MAP_TYPE_SOCKMAP); if (test__start_subtest("sockhash sk_msg load helpers")) test_skmsg_helpers(BPF_MAP_TYPE_SOCKHASH); + if (test__start_subtest("sockmap update")) + test_sockmap_update(BPF_MAP_TYPE_SOCKMAP); + if (test__start_subtest("sockhash update")) + test_sockmap_update(BPF_MAP_TYPE_SOCKHASH); + if (test__start_subtest("sockmap update in unsafe context")) + test_sockmap_invalid_update(); } diff --git a/tools/testing/selftests/bpf/progs/test_sockmap_invalid_update.c b/tools/testing/selftests/bpf/progs/test_sockmap_invalid_update.c new file mode 100644 index 000000000000..02a59e220cbc --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_sockmap_invalid_update.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2020 Cloudflare +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +struct { + __uint(type, BPF_MAP_TYPE_SOCKMAP); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} map SEC(".maps"); + +SEC("sockops") +int bpf_sockmap(struct bpf_sock_ops *skops) +{ + __u32 key = 0; + + if (skops->sk) + bpf_map_update_elem(&map, &key, skops->sk, 0); + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/test_sockmap_update.c b/tools/testing/selftests/bpf/progs/test_sockmap_update.c new file mode 100644 index 000000000000..9d0c9f28cab2 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_sockmap_update.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2020 Cloudflare +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +struct { + __uint(type, BPF_MAP_TYPE_SOCKMAP); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} src SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_SOCKMAP); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} dst_sock_map SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_SOCKHASH); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} dst_sock_hash SEC(".maps"); + +SEC("classifier/copy_sock_map") +int copy_sock_map(void *ctx) +{ + struct bpf_sock *sk; + bool failed = false; + __u32 key = 0; + + sk = bpf_map_lookup_elem(&src, &key); + if (!sk) + return SK_DROP; + + if (bpf_map_update_elem(&dst_sock_map, &key, sk, 0)) + failed = true; + + if (bpf_map_update_elem(&dst_sock_hash, &key, sk, 0)) + failed = true; + + bpf_sk_release(sk); + return failed ? SK_DROP : SK_PASS; +} + +char _license[] SEC("license") = "GPL";