Current implementation does not allow typedef func_proto.
But it is actually allowed.
-bash-4.4$ cat t.c
typedef int (f) (int);
f *g;
-bash-4.4$ clang -O2 -g -c -target bpf t.c -Xclang -target-feature -Xclang
+dwarfris
-bash-4.4$ pahole -JV t.o
File t.o:
[1] PTR (anon) type_id=2
[2] TYPEDEF f type_id=3
[3] FUNC_PROTO (anon) return=4 args=(4 (anon))
[4] INT int size=4 bit_offset=0 nr_bits=32 encoding=SIGNED
-bash-4.4$
This patch related btf verifier to allow such (typedef func_proto)
patterns.
Fixes: 2667a2626f4d ("bpf: btf: Add BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO")
Acked-by: Martin KaFai Lau <[email protected]>
Signed-off-by: Yonghong Song <[email protected]>
---
kernel/bpf/btf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index befe570be5ba..c57bd10340ed 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -1459,7 +1459,8 @@ static int btf_modifier_resolve(struct btf_verifier_env
*env,
/* "typedef void new_void", "const void"...etc */
if (!btf_type_is_void(next_type) &&
- !btf_type_is_fwd(next_type)) {
+ !btf_type_is_fwd(next_type) &&
+ !btf_type_is_func_proto(next_type)) {
btf_verifier_log_type(env, v->t, "Invalid type_id");
return -EINVAL;
}
--
2.17.1