diff --git a/app/src/net.c b/app/src/net.c
index b961c8eb..83aa7035 100644
--- a/app/src/net.c
+++ b/app/src/net.c
@@ -94,7 +94,7 @@ ssize_t net_send_all(socket_t socket, const void *buf, size_t len) {
             return -1;
         }
         len -= w;
-        buf += w;
+        buf = (char *) buf + w;
     }
     return w;
 }