From f0f85635be419356cf786a5accffec20eb8140a1 Mon Sep 17 00:00:00 2001
From: Old-Ding <35417409+Old-Ding@users.noreply.github.com>
Date: Mon, 6 Jul 2026 04:23:04 +0800
Subject: [PATCH] examples: Fix network echo receive terminators

The netloop and poll TCP echo examples receive up to IOBUFFER_SIZE bytes and then append a NUL terminator before logging the data. A full-size receive can therefore write one byte past the input buffer.

Reserve one extra byte in the buffers that are terminated after recv(). Keep the receive limit and echo length capped at IOBUFFER_SIZE so the data path is unchanged.

Signed-off-by: Old-Ding <35417409+Old-Ding@users.noreply.github.com>
---
 examples/netloop/lo_listener.c | 2 +-
 examples/netloop/lo_main.c     | 2 +-
 examples/poll/host.c           | 2 +-
 examples/poll/net_listener.c   | 2 +-
 examples/poll/net_reader.c     | 2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/examples/netloop/lo_listener.c b/examples/netloop/lo_listener.c
index 20f72ad9c56..57362cec82a 100644
--- a/examples/netloop/lo_listener.c
+++ b/examples/netloop/lo_listener.c
@@ -64,7 +64,7 @@ struct net_listener_s
   struct sockaddr_in addr;
   fd_set          master;
   fd_set          working;
-  char            buffer[IOBUFFER_SIZE];
+  char            buffer[IOBUFFER_SIZE + 1];
   int             listensd;
   int             mxsd;
 };
diff --git a/examples/netloop/lo_main.c b/examples/netloop/lo_main.c
index 513278b0893..3c6a0c72f0a 100644
--- a/examples/netloop/lo_main.c
+++ b/examples/netloop/lo_main.c
@@ -63,7 +63,7 @@ static int lo_client(void)
 {
   struct sockaddr_in myaddr;
   char outbuf[IOBUFFER_SIZE];
-  char inbuf[IOBUFFER_SIZE];
+  char inbuf[IOBUFFER_SIZE + 1];
   int sockfd;
   int len;
   int nbytessent;
diff --git a/examples/poll/host.c b/examples/poll/host.c
index 740bccb2200..8d42dd99792 100644
--- a/examples/poll/host.c
+++ b/examples/poll/host.c
@@ -64,7 +64,7 @@ int main(int argc, char **argv, char **envp)
 {
   struct sockaddr_in myaddr;
   char outbuf[IOBUFFER_SIZE];
-  char inbuf[IOBUFFER_SIZE];
+  char inbuf[IOBUFFER_SIZE + 1];
   int sockfd;
   int len;
   int nbytessent;
diff --git a/examples/poll/net_listener.c b/examples/poll/net_listener.c
index e20306d6c2c..3c72e16e383 100644
--- a/examples/poll/net_listener.c
+++ b/examples/poll/net_listener.c
@@ -64,7 +64,7 @@ struct net_listener_s
   struct sockaddr_in addr;
   fd_set          master;
   fd_set          working;
-  char            buffer[IOBUFFER_SIZE];
+  char            buffer[IOBUFFER_SIZE + 1];
   int             listensd;
   int             mxsd;
 };
diff --git a/examples/poll/net_reader.c b/examples/poll/net_reader.c
index 28817976366..191f398753e 100644
--- a/examples/poll/net_reader.c
+++ b/examples/poll/net_reader.c
@@ -121,7 +121,7 @@ static void net_configure(void)
 static void net_receive(int sd)
 {
   struct timeval timeout;
-  char buffer[IOBUFFER_SIZE];
+  char buffer[IOBUFFER_SIZE + 1];
   char *ptr;
   fd_set readset;
   int nbytes;