From bab2b4a5f24665e66dcf27ed7efede94cc94b803 Mon Sep 17 00:00:00 2001
From: Old-Ding <35417409+Old-Ding@users.noreply.github.com>
Date: Mon, 6 Jul 2026 09:11:16 +0800
Subject: [PATCH] libc/stream: Check lowout bounds before access

Check the provided length before reading the current lowoutstream byte. This avoids reading past zero-length or fully consumed buffers before the loop condition stops.

Generated-by: OpenAI Codex
Signed-off-by: Old-Ding <35417409+Old-Ding@users.noreply.github.com>
---
 libs/libc/stream/lib_lowoutstream.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libs/libc/stream/lib_lowoutstream.c b/libs/libc/stream/lib_lowoutstream.c
index 6fe9fbf7941..5a7b64b73c4 100644
--- a/libs/libc/stream/lib_lowoutstream.c
+++ b/libs/libc/stream/lib_lowoutstream.c
@@ -86,7 +86,7 @@ static ssize_t lowoutstream_puts(FAR struct lib_outstream_s *self,
   size_t idx          = 0;
   DEBUGASSERT(self);
 
-  while (str[idx] != 0 && idx < len)
+  while (idx < len && str[idx] != 0)
     {
       lowoutstream_putc(self, str[idx]);
       idx++;