summaryrefslogtreecommitdiff
path: root/tools
diff options
context:
space:
mode:
authorJakub Sitnicki <jakub@cloudflare.com>2025-11-05 23:19:50 +0300
committerMartin KaFai Lau <martin.lau@kernel.org>2025-11-10 21:52:32 +0300
commit354d020c29f72513dce4f3902890158d99b67b67 (patch)
treeb444ca32c590af6fca926bb615c3a4a3d92b7945 /tools
parent1e1357fde808a35c6069759298660134e5dab053 (diff)
downloadlinux-354d020c29f72513dce4f3902890158d99b67b67.tar.xz
selftests/bpf: Cover skb metadata access after vlan push/pop helper
Add a test to verify that skb metadata remains accessible after calling bpf_skb_vlan_push() and bpf_skb_vlan_pop(), which modify the packet headroom. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20251105-skb-meta-rx-path-v4-13-5ceb08a9b37b@cloudflare.com
Diffstat (limited to 'tools')
-rw-r--r--tools/testing/selftests/bpf/prog_tests/xdp_context_test_run.c6
-rw-r--r--tools/testing/selftests/bpf/progs/test_xdp_meta.c43
2 files changed, 49 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_context_test_run.c b/tools/testing/selftests/bpf/prog_tests/xdp_context_test_run.c
index a129c3057202..97c8f876f673 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_context_test_run.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_context_test_run.c
@@ -478,6 +478,12 @@ void test_xdp_context_tuntap(void)
test_tuntap_mirred(skel->progs.ing_xdp,
skel->progs.clone_meta_dynptr_rw_before_meta_dynptr_write,
&skel->bss->test_pass);
+ /* Tests for BPF helpers which touch headroom */
+ if (test__start_subtest("helper_skb_vlan_push_pop"))
+ test_tuntap(skel->progs.ing_xdp,
+ skel->progs.helper_skb_vlan_push_pop,
+ NULL, /* tc prio 2 */
+ &skel->bss->test_pass);
test_xdp_meta__destroy(skel);
}
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_meta.c b/tools/testing/selftests/bpf/progs/test_xdp_meta.c
index a70de55c6997..04c7487bb350 100644
--- a/tools/testing/selftests/bpf/progs/test_xdp_meta.c
+++ b/tools/testing/selftests/bpf/progs/test_xdp_meta.c
@@ -44,6 +44,16 @@ static bool check_metadata(const char *file, int line, __u8 *meta_have)
#define check_metadata(meta_have) check_metadata(__FILE__, __LINE__, meta_have)
+static bool check_skb_metadata(const char *file, int line, struct __sk_buff *skb)
+{
+ __u8 *data_meta = ctx_ptr(skb, data_meta);
+ __u8 *data = ctx_ptr(skb, data);
+
+ return data_meta + META_SIZE <= data && (check_metadata)(file, line, data_meta);
+}
+
+#define check_skb_metadata(skb) check_skb_metadata(__FILE__, __LINE__, skb)
+
SEC("tc")
int ing_cls(struct __sk_buff *ctx)
{
@@ -525,4 +535,37 @@ out:
return TC_ACT_SHOT;
}
+SEC("tc")
+int helper_skb_vlan_push_pop(struct __sk_buff *ctx)
+{
+ int err;
+
+ /* bpf_skb_vlan_push assumes HW offload for primary VLAN tag. Only
+ * secondary tag push triggers an actual MAC header modification.
+ */
+ err = bpf_skb_vlan_push(ctx, 0, 42);
+ if (err)
+ goto out;
+ err = bpf_skb_vlan_push(ctx, 0, 207);
+ if (err)
+ goto out;
+
+ if (!check_skb_metadata(ctx))
+ goto out;
+
+ err = bpf_skb_vlan_pop(ctx);
+ if (err)
+ goto out;
+ err = bpf_skb_vlan_pop(ctx);
+ if (err)
+ goto out;
+
+ if (!check_skb_metadata(ctx))
+ goto out;
+
+ test_pass = true;
+out:
+ return TC_ACT_SHOT;
+}
+
char _license[] SEC("license") = "GPL";