bpf: fix cgroup_skb prog test run direct packet access

This is needed in the context of Tetragon to test cgroup_skb programs
using BPF_PROG_TEST_RUN with direct packet access.

Commit b39b5f411dcf ("bpf: add cg_skb_is_valid_access for
BPF_PROG_TYPE_CGROUP_SKB") added direct packet access for cgroup_skb
programs and following commit 2cb494a36c98 ("bpf: add tests for direct
packet access from CGROUP_SKB") added tests to the verifier to ensure
that access to skb fields was possible and also fixed
bpf_prog_test_run_skb. However, is_direct_pkt_access was never set to
true for this program type, so data pointers were not computed when
using prog_test_run, making data_end always equal to zero (data_meta is
not accessible for cgroup_skb).

Signed-off-by: Mahe Tardy <mahe.tardy@gmail.com>
Link: https://lore.kernel.org/r/20241125152603.375898-1-mahe.tardy@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 501ec4249fedc3d34fe39aff50eea66f82b88a11..5586c13926074809de159b812f7f228d6da4535f 100644 (file)
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -1018,6 +1018,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
        case BPF_PROG_TYPE_LWT_IN:
        case BPF_PROG_TYPE_LWT_OUT:
        case BPF_PROG_TYPE_LWT_XMIT:
+       case BPF_PROG_TYPE_CGROUP_SKB:
                is_direct_pkt_access = true;
                break;
        default: