1 files changed, 85 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/local_kptr_stash_fail.c b/tools/testing/selftests/bpf/progs/local_kptr_stash_fail.c
new file mode 100644
index 000000000000..fcf7a7567da2
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/local_kptr_stash_fail.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
+
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
+#include "../bpf_experimental.h"
+#include "bpf_misc.h"
+
+struct node_data {
+	long key;
+	long data;
+	struct bpf_rb_node node;
+};
+
+struct map_value {
+	struct node_data __kptr *node;
+};
+
+struct node_data2 {
+	long key[4];
+};
+
+/* This is necessary so that LLVM generates BTF for node_data struct
+ * If it's not included, a fwd reference for node_data will be generated but
+ * no struct. Example BTF of "node" field in map_value when not included:
+ *
+ * [10] PTR '(anon)' type_id=35
+ * [34] FWD 'node_data' fwd_kind=struct
+ * [35] TYPE_TAG 'kptr_ref' type_id=34
+ */
+struct node_data *just_here_because_btf_bug;
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__type(key, int);
+	__type(value, struct map_value);
+	__uint(max_entries, 2);
+} some_nodes SEC(".maps");
+
+SEC("tc")
+__failure __msg("invalid kptr access, R2 type=ptr_node_data2 expected=ptr_node_data")
+long stash_rb_nodes(void *ctx)
+{
+	struct map_value *mapval;
+	struct node_data2 *res;
+	int idx = 0;
+
+	mapval = bpf_map_lookup_elem(&some_nodes, &idx);
+	if (!mapval)
+		return 1;
+
+	res = bpf_obj_new(typeof(*res));
+	if (!res)
+		return 1;
+	res->key[0] = 40;
+
+	res = bpf_kptr_xchg(&mapval->node, res);
+	if (res)
+		bpf_obj_drop(res);
+	return 0;
+}
+
+SEC("tc")
+__failure __msg("R1 must have zero offset when passed to release func")
+long drop_rb_node_off(void *ctx)
+{
+	struct map_value *mapval;
+	struct node_data *res;
+	int idx = 0;
+
+	mapval = bpf_map_lookup_elem(&some_nodes, &idx);
+	if (!mapval)
+		return 1;
+
+	res = bpf_obj_new(typeof(*res));
+	if (!res)
+		return 1;
+	/* Try releasing with graph node offset */
+	bpf_obj_drop(&res->node);
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";