From 69622ff37db03ed818aa9141cdbe874267a6d61d Mon Sep 17 00:00:00 2001
From: x2018 <xkernel.wang@foxmail.com>
Date: Wed, 5 Nov 2025 23:50:51 +0800
Subject: [PATCH] tool_help: add checks to avoid unsigned wrap around

Closes #19377
---
 src/tool_help.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/tool_help.c b/src/tool_help.c
index 7a3a4a3bf4..4509fa2b94 100644
--- a/src/tool_help.c
+++ b/src/tool_help.c
@@ -87,14 +87,18 @@ static void print_category(unsigned int category, unsigned int cols)
     if(len > longdesc)
       longdesc = len;
   }
-  if(longopt + longdesc > cols)
+
+  if(longdesc > cols)
+    longopt = 0; /* avoid wrap-around */
+  else if(longopt + longdesc > cols)
     longopt = cols - longdesc;
 
   for(i = 0; helptext[i].opt; ++i)
     if(helptext[i].categories & category) {
       size_t opt = longopt;
       size_t desclen = strlen(helptext[i].desc);
-      if(opt + desclen >= (cols - 2)) {
+      /* avoid wrap-around */
+      if(cols >= 2 && opt + desclen >= (cols - 2)) {
         if(desclen < (cols - 2))
           opt = (cols - 3) - desclen;
         else
-- 
2.47.3