From f9d6242af292efbd0074d2ab97d9caa37ea351a9 Mon Sep 17 00:00:00 2001
From: Yosuke Shimizu <yosuke@wolfssl.com>
Date: Fri, 5 Jun 2026 16:25:02 +0900
Subject: [PATCH] examples/client: guard rxBuf indexing against negative
 stream_read error

---
 examples/client/client.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/examples/client/client.c b/examples/client/client.c
index a6f3a7bef..6429d28b9 100644
--- a/examples/client/client.c
+++ b/examples/client/client.c
@@ -1170,8 +1170,10 @@ THREAD_RETURN WOLFSSH_THREAD client_test(void* args)
             }
         } while (ret == WS_WANT_READ || ret == WS_WANT_WRITE);
 
-        rxBuf[ret] = '\0';
-        printf("Server said: %s\n", rxBuf);
+        if (ret > 0 && ret < (int)sizeof(rxBuf)) {
+            rxBuf[ret] = '\0';
+            printf("Server said: %s\n", rxBuf);
+        }
 
 #if defined(WOLFSSL_PTHREADS) && defined(WOLFSSL_TEST_GLOBAL_REQ)
         sleep(10);