resolved merge conflict

tsk/img/img_io.c

@@ -211,13 +211,18 @@ tsk_img_read(TSK_IMG_INFO * a_img_info, TSK_OFF_T a_off,
             // Determine the offset relative to the start of the cached data.
             rel_off = a_off - a_img_info->cache_off[cache_next];
 
+            // Make sure we were able to read sufficient data into the cache.
+            if (rel_off > (TSK_OFF_T) read_count) {
+                len2 = 0;
+            }
             // Make sure not to copy more than is available in the cache.
-            if ((rel_off + (TSK_OFF_T) len2) > (TSK_OFF_T) read_count) {
+            else if ((rel_off + (TSK_OFF_T) len2) > (TSK_OFF_T) read_count) {
                 len2 = (size_t) (read_count - rel_off);
             }
-
-            memcpy(a_buf, &(a_img_info->cache[cache_next][rel_off]), len2);
-
+            // Only copy data when we have something to copy.
+            if (len2 > 0) {
+                memcpy(a_buf, &(a_img_info->cache[cache_next][rel_off]), len2);
+            }
             read_count = (ssize_t) len2;
         }
         else {