diff --git a/client.s b/client.s
index 38e08cb..d3a1e7a 100644
--- a/client.s
+++ b/client.s
@@ -31,7 +31,7 @@ client__pollin:
     mov rax, SYS_READ
     mov rsi, r13
     mov rdx, 255
-    sub rdx, [rsi + OFFSET_CLIENT_BUFFER_LEN]
+    sub dl, [rsi + OFFSET_CLIENT_BUFFER_LEN]
     syscall
 
     cmp rax, 0