SELinux: use ARRAY_SIZE

ARRAY_SIZE is more concise to use when the size of an array is divided
by the size of its type or the size of its first element.

The Coccinelle semantic patch that makes this change is as follows:

// <smpl>
@@
type T;
T[] E;
@@

- (sizeof(E)/sizeof(E[...]))
+ ARRAY_SIZE(E)
// </smpl>
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>

security/selinux/ss/policydb.c

@@ -2608,7 +2608,7 @@ static int mls_write_range_helper(struct mls_range *r, void *fp)
 	if (!eq)
 		buf[2] = cpu_to_le32(r->level[1].sens);
 
-	BUG_ON(items > (sizeof(buf)/sizeof(buf[0])));
+	BUG_ON(items > ARRAY_SIZE(buf));
 
 	rc = put_entry(buf, sizeof(u32), items, fp);
 	if (rc)
@@ -2990,7 +2990,7 @@ static int role_write(void *vkey, void *datum, void *ptr)
 	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
 		buf[items++] = cpu_to_le32(role->bounds);
 
-	BUG_ON(items > (sizeof(buf)/sizeof(buf[0])));
+	BUG_ON(items > ARRAY_SIZE(buf));
 
 	rc = put_entry(buf, sizeof(u32), items, fp);
 	if (rc)
@@ -3040,7 +3040,7 @@ static int type_write(void *vkey, void *datum, void *ptr)
 	} else {
 		buf[items++] = cpu_to_le32(typdatum->primary);
 	}
-	BUG_ON(items > (sizeof(buf) / sizeof(buf[0])));
+	BUG_ON(items > ARRAY_SIZE(buf));
 	rc = put_entry(buf, sizeof(u32), items, fp);
 	if (rc)
 		return rc;
@@ -3069,7 +3069,7 @@ static int user_write(void *vkey, void *datum, void *ptr)
 	buf[items++] = cpu_to_le32(usrdatum->value);
 	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
 		buf[items++] = cpu_to_le32(usrdatum->bounds);
-	BUG_ON(items > (sizeof(buf) / sizeof(buf[0])));
+	BUG_ON(items > ARRAY_SIZE(buf));
 	rc = put_entry(buf, sizeof(u32), items, fp);
 	if (rc)
 		return rc;