[PATCH bpf-next 3/3] selftests/bpf: Add tests for writing to nf_conn:mark

From: Daniel Xu
Date: Mon Aug 15 2022 - 18:04:50 EST


Add a simple extension to the existing selftest to write to
nf_conn:mark. Also add a failure test for writing to unsupported field.

Signed-off-by: Daniel Xu <dxu@xxxxxxxxx>
---
tools/testing/selftests/bpf/prog_tests/bpf_nf.c | 1 +
tools/testing/selftests/bpf/progs/test_bpf_nf.c | 6 ++++--
.../testing/selftests/bpf/progs/test_bpf_nf_fail.c | 14 ++++++++++++++
3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
index 544bf90ac2a7..45389c39f211 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
@@ -17,6 +17,7 @@ struct {
{ "set_status_after_insert", "kernel function bpf_ct_set_status args#0 expected pointer to STRUCT nf_conn___init but" },
{ "change_timeout_after_alloc", "kernel function bpf_ct_change_timeout args#0 expected pointer to STRUCT nf_conn but" },
{ "change_status_after_alloc", "kernel function bpf_ct_change_status args#0 expected pointer to STRUCT nf_conn but" },
+ { "write_not_allowlisted_field", "no write support to nf_conn at off" },
};

enum {
diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
index 2722441850cc..638b6642d20f 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
@@ -175,8 +175,10 @@ nf_ct_test(struct nf_conn *(*lookup_fn)(void *, struct bpf_sock_tuple *, u32,
sizeof(opts_def));
if (ct) {
test_exist_lookup = 0;
- if (ct->mark == 42)
- test_exist_lookup_mark = 43;
+ if (ct->mark == 42) {
+ ct->mark++;
+ test_exist_lookup_mark = ct->mark;
+ }
bpf_ct_release(ct);
} else {
test_exist_lookup = opts_def.error;
diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf_fail.c b/tools/testing/selftests/bpf/progs/test_bpf_nf_fail.c
index bf79af15c808..0e4759ab38ff 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_nf_fail.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_nf_fail.c
@@ -69,6 +69,20 @@ int lookup_insert(struct __sk_buff *ctx)
return 0;
}

+SEC("?tc")
+int write_not_allowlisted_field(struct __sk_buff *ctx)
+{
+ struct bpf_ct_opts___local opts = {};
+ struct bpf_sock_tuple tup = {};
+ struct nf_conn *ct;
+
+ ct = bpf_skb_ct_lookup(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));
+ if (!ct)
+ return 0;
+ ct->status = 0xF00;
+ return 0;
+}
+
SEC("?tc")
int set_timeout_after_insert(struct __sk_buff *ctx)
{
--
2.37.1