return obj;
}
+void *bpf_rdonly_cast(void *obj__ign, u32 btf_id__k)
+{
+ return obj__ign;
+}
+
__diag_pop();
BTF_SET8_START(generic_btf_ids)
BTF_SET8_START(common_btf_ids)
BTF_ID_FLAGS(func, bpf_cast_to_kern_ctx)
+BTF_ID_FLAGS(func, bpf_rdonly_cast)
BTF_SET8_END(common_btf_ids)
static const struct btf_kfunc_id_set common_kfunc_set = {
KF_bpf_list_pop_front,
KF_bpf_list_pop_back,
KF_bpf_cast_to_kern_ctx,
+ KF_bpf_rdonly_cast,
};
BTF_SET_START(special_kfunc_set)
BTF_ID(func, bpf_list_pop_front)
BTF_ID(func, bpf_list_pop_back)
BTF_ID(func, bpf_cast_to_kern_ctx)
+BTF_ID(func, bpf_rdonly_cast)
BTF_SET_END(special_kfunc_set)
BTF_ID_LIST(special_kfunc_list)
BTF_ID(func, bpf_list_pop_front)
BTF_ID(func, bpf_list_pop_back)
BTF_ID(func, bpf_cast_to_kern_ctx)
+BTF_ID(func, bpf_rdonly_cast)
static enum kfunc_ptr_arg_type
get_kfunc_ptr_arg_type(struct bpf_verifier_env *env,
u32 i, nargs, func_id, ptr_type_id;
int err, insn_idx = *insn_idx_p;
const struct btf_param *args;
+ const struct btf_type *ret_t;
struct btf *desc_btf;
u32 *kfunc_flags;
if (meta.btf == btf_vmlinux && btf_id_set_contains(&special_kfunc_set, meta.func_id)) {
if (meta.func_id == special_kfunc_list[KF_bpf_obj_new_impl]) {
- const struct btf_type *ret_t;
struct btf *ret_btf;
u32 ret_btf_id;
regs[BPF_REG_0].type = PTR_TO_BTF_ID | PTR_TRUSTED;
regs[BPF_REG_0].btf = desc_btf;
regs[BPF_REG_0].btf_id = meta.ret_btf_id;
+ } else if (meta.func_id == special_kfunc_list[KF_bpf_rdonly_cast]) {
+ ret_t = btf_type_by_id(desc_btf, meta.arg_constant.value);
+ if (!ret_t || !btf_type_is_struct(ret_t)) {
+ verbose(env,
+ "kfunc bpf_rdonly_cast type ID argument must be of a struct\n");
+ return -EINVAL;
+ }
+
+ mark_reg_known_zero(env, regs, BPF_REG_0);
+ regs[BPF_REG_0].type = PTR_TO_BTF_ID | PTR_UNTRUSTED;
+ regs[BPF_REG_0].btf = desc_btf;
+ regs[BPF_REG_0].btf_id = meta.arg_constant.value;
} else {
verbose(env, "kernel function %s unhandled dynamic return type\n",
meta.func_name);
insn_buf[1] = addr[1];
insn_buf[2] = *insn;
*cnt = 3;
- } else if (desc->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx]) {
+ } else if (desc->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx] ||
+ desc->func_id == special_kfunc_list[KF_bpf_rdonly_cast]) {
insn_buf[0] = BPF_MOV64_REG(BPF_REG_0, BPF_REG_1);
*cnt = 1;
}