wutdevoptab: Prevent file-offset overflow in seek implementation

libraries/wutdevoptab/devoptab_fs_seek.c

@@ -49,11 +49,14 @@ __wut_fs_seek(struct _reent *r,
       return -1;
    }
 
-   // TODO: A better check that prevents overflow.
    if(pos < 0 && offset < -pos) {
       // Don't allow seek to before the beginning of the file
       r->_errno = EINVAL;
       return -1;
+   } else if (offset + pos > UINT32_MAX) {
+      // Check for overflow
+      r->_errno = EINVAL;
+      return -1;
    }
 
    uint32_t old_offset = file->offset;