Re: [RFC PATCH bpf-next v2 3/9] bpf: Replace RET_XXX_OR_NULL with RET_XXX | PTR_MAYBE_NULL
From: Alexei Starovoitov <hidden>
Date: 2021-12-01 20:30:52
On Mon, Nov 29, 2021 at 05:29:42PM -0800, Hao Luo wrote:
quoted hunk ↗ jump to hunk
/* update return register (already marked as written above) */ - if (fn->ret_type == RET_INTEGER) { + ret_type = fn->ret_type; + if (ret_type == RET_INTEGER) { /* sets type to SCALAR_VALUE */ mark_reg_unknown(env, regs, BPF_REG_0); - } else if (fn->ret_type == RET_VOID) { + } else if (ret_type == RET_VOID) { regs[BPF_REG_0].type = NOT_INIT; - } else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL || - fn->ret_type == RET_PTR_TO_MAP_VALUE) { + } else if (BPF_BASE_TYPE(ret_type) == RET_PTR_TO_MAP_VALUE) { /* There is no offset yet applied, variable or fixed */ mark_reg_known_zero(env, regs, BPF_REG_0); /* remember map_ptr, so that check_map_access()@@ -6530,28 +6536,27 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn } regs[BPF_REG_0].map_ptr = meta.map_ptr; regs[BPF_REG_0].map_uid = meta.map_uid; - if (fn->ret_type == RET_PTR_TO_MAP_VALUE) { + if (ret_type_may_be_null(fn->ret_type)) {
it should have been ret_type here?
+ regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
+ } else {
regs[BPF_REG_0].type = PTR_TO_MAP_VALUE;