bpf: btf: Check array t->size

This patch ensures array's t->size is 0.

The array size is decided by its individual elem's size and the
number of elements.  Hence, t->size is not used and
it must be 0.

A test case is added to test_btf.c

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c
index 35064df688c1..fd8246e84149 100644
--- a/tools/testing/selftests/bpf/test_btf.c
+++ b/tools/testing/selftests/bpf/test_btf.c
@@ -1179,6 +1179,29 @@ static struct btf_raw_test raw_tests[] = {
 },
 
 {
+        .descr = "array test. t->size != 0\"",
+        .raw_types = {
+                /* int */                               /* [1] */
+                BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
+                /* int[16] */                           /* [2] */
+                BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_ARRAY, 0, 0), 1),
+                BTF_ARRAY_ENC(1, 1, 16),
+                BTF_END_RAW,
+        },
+        .str_sec = "",
+        .str_sec_size = sizeof(""),
+        .map_type = BPF_MAP_TYPE_ARRAY,
+        .map_name = "array_test_map",
+        .key_size = sizeof(int),
+        .value_size = sizeof(int),
+        .key_type_id = 1,
+        .value_type_id = 1,
+        .max_entries = 4,
+        .btf_load_err = true,
+        .err_str = "size != 0",
+},
+
+{
         .descr = "int test. invalid int_data",
         .raw_types = {
                 BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), 4),