On Fri, 2025-08-01 at 18:19 +0200, Paul Chaignon wrote:
[...]
> > > @@ -21445,7 +21445,7 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
> > > &target_size);
> > > if (cnt == 0 || cnt >= INSN_BUF_SIZE ||
> > > (ctx_field_size && !target_size)) {
> > > - verifier_bug(env, "error during ctx access conversion");
> > > + verifier_bug(env, "error during ctx access conversion (%d)", cnt);
> >
> > Nit: maybe print the rest of the fields as well?
>
> I considered it but didn't want to unnecessarily bloat the message.
> Knowing cnt is enough to know which of the three conditions is true. If
> the last one is true, then knowing the values of ctx_field_size and
> target_size doesn't really help us because the issue is just that one is
> set (ctx_field_size in _is_valid_access) while the other wasn't
> (target_size in _convert_ctx_accesses). That indicates a mismatch
> between the two functions for that particular program type.
Ack, makes sense. Thank you for explaining.
