On Fri, 2024-05-10 at 05:28 -0700, Vadim Fedorenko wrote: > Some arguments to kfuncs might be NULL in some cases. But currently it's > not possible to pass NULL to any BTF structures because the check for > the suffix is located after all type checks. Move it to earlier place > to allow nullable args. > > Signed-off-by: Vadim Fedorenko <vadfed@xxxxxxxx> > --- Acked-by: Eduard Zingerman <eddyz87@xxxxxxxxx> > kernel/bpf/verifier.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c > index 9e3aba08984e..ed67aed3c284 100644 > --- a/kernel/bpf/verifier.c > +++ b/kernel/bpf/verifier.c > @@ -11179,6 +11179,9 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, > if (btf_is_prog_ctx_type(&env->log, meta->btf, t, resolve_prog_type(env->prog), argno)) > return KF_ARG_PTR_TO_CTX; > > + if (is_kfunc_arg_nullable(meta->btf, &args[argno]) && register_is_null(reg)) > + return KF_ARG_PTR_TO_NULL; > + Nit: maybe move this above the KF_ARG_PTR_TO_CTX check as well?
