diff mbox series

[bpf-next,1/2] bpf: btf: Check array t->size

Message ID 20180602160651.3960897-1-kafai@fb.com
State Accepted, archived
Delegated to: BPF Maintainers
Headers show
Series [bpf-next,1/2] bpf: btf: Check array t->size | expand

Commit Message

Martin KaFai Lau June 2, 2018, 4:06 p.m. UTC 
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>
---
 kernel/bpf/btf.c                       |  5 +++++
 tools/testing/selftests/bpf/test_btf.c | 23 +++++++++++++++++++++++
 2 files changed, 28 insertions(+)

Comments

Alexei Starovoitov June 2, 2018, 6:31 p.m. UTC | #1 
On Sat, Jun 02, 2018 at 09:06:50AM -0700, Martin KaFai Lau wrote:
> 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>

Both applied.
Please provide cover letter with short description next time
when sending series.
Thanks
diff mbox series

Patch

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 3d20aa1f4b54..84ad532f2854 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -1342,6 +1342,11 @@  static s32 btf_array_check_meta(struct btf_verifier_env *env,
 		return -EINVAL;
 	}
 
+	if (t->size) {
+		btf_verifier_log_type(env, t, "size != 0");
+		return -EINVAL;
+	}
+
 	/* Array elem type and index type cannot be in type void,
 	 * so !array->type and !array->index_type are not allowed.
 	 */
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),