diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 64739308902f7..86883b3c97d20 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -6762,7 +6762,7 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type,
 	/* skip modifiers */
 	while (btf_type_is_modifier(t))
 		t = btf_type_by_id(btf, t->type);
-	if (btf_type_is_small_int(t) || btf_is_any_enum(t) || __btf_type_is_struct(t))
+	if (btf_type_is_small_int(t) || btf_is_any_enum(t) || btf_type_is_struct(t))
 		/* accessing a scalar */
 		return true;
 	if (!btf_type_is_ptr(t)) {
@@ -7334,7 +7334,7 @@ static int __get_type_size(struct btf *btf, u32 btf_id,
 	if (btf_type_is_ptr(t))
 		/* kernel size of pointer. Not BPF's size of pointer*/
 		return sizeof(void *);
-	if (btf_type_is_int(t) || btf_is_any_enum(t) || __btf_type_is_struct(t))
+	if (btf_type_is_int(t) || btf_is_any_enum(t) || btf_type_is_struct(t))
 		return t->size;
 	return -EINVAL;
 }
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 4a862d6053861..c65d468fd6012 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -574,6 +574,16 @@ noinline int bpf_fentry_test10(const void *a)
 	return (long)a;
 }
 
+typedef union {
+	void *arg0;
+	int *arg1;
+} union_test_t;
+
+noinline int bpf_fentry_test11(union_test_t t)
+{
+	return (int)(long)t.arg0;
+}
+
 noinline void bpf_fentry_test_sinfo(struct skb_shared_info *sinfo)
 {
 }
@@ -688,6 +698,7 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
 	struct bpf_fentry_test_t arg = {};
 	u16 side_effect = 0, ret = 0;
 	int b = 2, err = -EFAULT;
+	union_test_t utt = {};
 	u32 retval = 0;
 
 	if (kattr->test.flags || kattr->test.cpu || kattr->test.batch_size)
@@ -705,7 +716,8 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
 		    bpf_fentry_test7((struct bpf_fentry_test_t *)0) != 0 ||
 		    bpf_fentry_test8(&arg) != 0 ||
 		    bpf_fentry_test9(&retval) != 0 ||
-		    bpf_fentry_test10((void *)0) != 0)
+		    bpf_fentry_test10((void *)0) != 0 ||
+		    bpf_fentry_test11(utt) != 0)
 			goto out;
 		break;
 	case BPF_MODIFY_RETURN:
diff --git a/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c b/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c
index 03942cec07e56..ff379836b5f00 100644
--- a/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c
+++ b/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c
@@ -77,4 +77,16 @@ __naked void ctx_access_const_void_pointer_accept(void)
 "	::: __clobber_all);
 }
 
+SEC("fentry/bpf_fentry_test11")
+__description("btf_ctx_access union arg accept")
+__success __retval(0)
+__naked void ctx_access_union_arg_accept(void)
+{
+	asm volatile ("					\
+	r2 = *(u64 *)(r1 + 0);		/* load 1st argument value (union) */\
+	r0 = 0;						\
+	exit;						\
+"	::: __clobber_all);
+}
+
 char _license[] SEC("license") = "GPL";