A new field was added to the bpf_sk_lookup data that users can access. Add tests that validate that the new ifindex field contains the right data.

Signed-off-by: Mark Pashmfouroush markpash@cloudflare.com

diff --git a/tools/testing/selftests/bpf/prog_tests/sk_lookup.c b/tools/testing/selftests/bpf/prog_tests/sk_lookup.c index 6db07401bc49..57846cc7ce36 100644 --- a/tools/testing/selftests/bpf/prog_tests/sk_lookup.c +++ b/tools/testing/selftests/bpf/prog_tests/sk_lookup.c @@ -937,6 +937,37 @@ static void test_drop_on_lookup(struct test_sk_lookup *skel) .connect_to = { EXT_IP6, EXT_PORT }, .listen_at = { EXT_IP6, INT_PORT }, }, + /* The program will drop on success, meaning that the ifindex + * was 1. + */ + { + .desc = "TCP IPv4 drop on valid ifindex", + .lookup_prog = skel->progs.check_ifindex, + .sotype = SOCK_STREAM, + .connect_to = { EXT_IP4, EXT_PORT }, + .listen_at = { EXT_IP4, EXT_PORT }, + }, + { + .desc = "TCP IPv6 drop on valid ifindex", + .lookup_prog = skel->progs.check_ifindex, + .sotype = SOCK_STREAM, + .connect_to = { EXT_IP6, EXT_PORT }, + .listen_at = { EXT_IP6, EXT_PORT }, + }, + { + .desc = "UDP IPv4 drop on valid ifindex", + .lookup_prog = skel->progs.check_ifindex, + .sotype = SOCK_DGRAM, + .connect_to = { EXT_IP4, EXT_PORT }, + .listen_at = { EXT_IP4, EXT_PORT }, + }, + { + .desc = "UDP IPv6 drop on valid ifindex", + .lookup_prog = skel->progs.check_ifindex, + .sotype = SOCK_DGRAM, + .connect_to = { EXT_IP6, EXT_PORT }, + .listen_at = { EXT_IP6, EXT_PORT }, + }, }; const struct test *t;

diff --git a/tools/testing/selftests/bpf/progs/test_sk_lookup.c b/tools/testing/selftests/bpf/progs/test_sk_lookup.c index 19d2465d9442..0f3283bfe3b6 100644 --- a/tools/testing/selftests/bpf/progs/test_sk_lookup.c +++ b/tools/testing/selftests/bpf/progs/test_sk_lookup.c @@ -84,6 +84,14 @@ int lookup_drop(struct bpf_sk_lookup *ctx) return SK_DROP; }

+SEC("sk_lookup") +int check_ifindex(struct bpf_sk_lookup *ctx) +{ + if (ctx->ifindex == 1) + return SK_DROP; + return SK_PASS; +} + SEC("sk_reuseport") int reuseport_pass(struct sk_reuseport_md *ctx) { diff --git a/tools/testing/selftests/bpf/verifier/ctx_sk_lookup.c b/tools/testing/selftests/bpf/verifier/ctx_sk_lookup.c index d78627be060f..0b3088da1e89 100644 --- a/tools/testing/selftests/bpf/verifier/ctx_sk_lookup.c +++ b/tools/testing/selftests/bpf/verifier/ctx_sk_lookup.c @@ -229,6 +229,24 @@ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, offsetof(struct bpf_sk_lookup, local_port)),

+ /* 1-byte read from ifindex field */ + BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex)), + BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex) + 1), + BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex) + 2), + BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex) + 3), + /* 2-byte read from ifindex field */ + BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex)), + BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex) + 2), + /* 4-byte read from ifindex field */ + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex)), + /* 8-byte read from sk field */ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, offsetof(struct bpf_sk_lookup, sk)), @@ -351,6 +369,20 @@ .expected_attach_type = BPF_SK_LOOKUP, .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, }, +{ + "invalid 8-byte read from bpf_sk_lookup ifindex field", + .insns = { + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, + offsetof(struct bpf_sk_lookup, ifindex)), + BPF_MOV32_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .errstr = "invalid bpf_context access", + .result = REJECT, + .prog_type = BPF_PROG_TYPE_SK_LOOKUP, + .expected_attach_type = BPF_SK_LOOKUP, + .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, +}, /* invalid 1,2,4-byte reads from 8-byte fields in bpf_sk_lookup */ { "invalid 4-byte read from bpf_sk_lookup sk field",