diff --git a/easyflash/src/ef_log.c b/easyflash/src/ef_log.c
index 7e4da13..72709e1 100644
--- a/easyflash/src/ef_log.c
+++ b/easyflash/src/ef_log.c
@@ -506,11 +506,11 @@ EfErrCode ef_log_read(size_t index, uint32_t *log, size_t size) {
         return result;
     }
 
-    if (size % 4 == 0) {
+    if (size % 4 != 0) {
         EF_DEBUG("Error: size must be word aligned.");
         return EF_READ_ERR;
     }
-    if (index < cur_using_size) {
+    if (index >= cur_using_size) {
         EF_DEBUG("Error: index out of ranges, current using size is %d", cur_using_size);
         return EF_READ_ERR;
     }