[PATCH v2] security/loadpin: Replace "kernel_read_file_str[j]" with function "kernel_read_file_id_str(j)".

[PATCH v2] security/loadpin: Replace "kernel_read_file_str[j]" with function "kernel_read_file_id_str(j)".

[Jiele zhao]

Actually Linux kernel already provide function "kernel_read_file_id_str()"
for secure access in "kernel_read_file.h".
And, in "parse_exclude()" function, it's better to use

	BUILD_BUG_ON(ARRAY_SIZE(kernel_read_file_str) - 1 ==
		ARRAY_SIZE(ignore_read_file_id));

to make sure the arrays stay within expected sizes.

Signed-off-by: Jiele zhao <unclexiaole@gmail.com>
---
 security/loadpin/loadpin.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
index b12f7d986b1e..3d59ff363087 100644
--- a/security/loadpin/loadpin.c
+++ b/security/loadpin/loadpin.c
@@ -210,9 +210,10 @@ static void __init parse_exclude(void)
 	 */
 	BUILD_BUG_ON(ARRAY_SIZE(exclude_read_files) !=
 		     ARRAY_SIZE(ignore_read_file_id));
-	BUILD_BUG_ON(ARRAY_SIZE(kernel_read_file_str) <
+	BUILD_BUG_ON(ARRAY_SIZE(kernel_read_file_str) - 1 ==
 		     ARRAY_SIZE(ignore_read_file_id));
 
+
 	for (i = 0; i < ARRAY_SIZE(exclude_read_files); i++) {
 		cur = exclude_read_files[i];
 		if (!cur)
@@ -221,9 +222,9 @@ static void __init parse_exclude(void)
 			continue;
 
 		for (j = 0; j < ARRAY_SIZE(ignore_read_file_id); j++) {
-			if (strcmp(cur, kernel_read_file_str[j]) == 0) {
+			if (strcmp(cur, kernel_read_file_id_str(j)) == 0) {
 				pr_info("excluding: %s\n",
-					kernel_read_file_str[j]);
+					kernel_read_file_id_str(j));
 				ignore_read_file_id[j] = 1;
 				/*
 				 * Can not break, because one read_file_str
-- 
2.25.1