diff --git a/tools/testing/selftests/bpf/progs/tailcall_callback.c b/tools/testing/selftests/bpf/progs/tailcall_callback.c index c41632cf423b..14fa7a87028e 100644 --- a/tools/testing/selftests/bpf/progs/tailcall_callback.c +++ b/tools/testing/selftests/bpf/progs/tailcall_callback.c @@ -44,6 +44,13 @@ int callback_loop(int index, void **cb_ctx) return ret ? 1 : 0; } +static __noinline +int callback_tail(int index, void **cb_ctx) +{ + bpf_tail_call_static(*cb_ctx, &jmp_table, 0); + return 0; +} + static __noinline int callback_empty(int index, void *data) { @@ -78,4 +85,13 @@ int tailcall_callback_2(struct __sk_buff *skb) return 0; } +/* callback with a direct tail call is rejected without a verifier bug */ +SEC("tc") +__failure __msg("cannot tail call within callback") +int tailcall_callback_3(struct __sk_buff *skb) +{ + bpf_loop(1, callback_tail, &skb, 0); + return 0; +} + char __license[] SEC("license") = "GPL";