[RFC bpf-next 2/7] bpf: resolve single typedef when walking structs

[Stanislav Fomichev <sdf@google.com>]

It is impossible to use skb_frag_t in the tracing program. So let's
resolve a single typedef when walking the struct.

Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
 kernel/bpf/btf.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index bd2cac057928..9bdaa1225e8a 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -6140,6 +6140,8 @@ static int btf_struct_walk(struct bpf_verifier_log *log, const struct btf *btf,
 	*flag = 0;
 again:
 	tname = __btf_name_by_offset(btf, t->name_off);
+	if (btf_type_is_typedef(t))
+		t = btf_type_by_id(btf, t->type);
 	if (!btf_type_is_struct(t)) {
 		bpf_log(log, "Type '%s' is not a struct\n", tname);
 		return -EINVAL;
-- 
2.41.0.162.gfafddb0af9-goog