From 8dbef2d424d124add3539fbb9ff90ab96eaa78b9 Mon Sep 17 00:00:00 2001
From: iceman1001 <iceman@iuse.se>
Date: Sun, 29 Mar 2026 10:21:15 +0700
Subject: [PATCH] null check and the prefered realloc pattern with a temporary
 variable

---
 client/src/util.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/client/src/util.c b/client/src/util.c
index e043a4120..8f887a6d4 100644
--- a/client/src/util.c
+++ b/client/src/util.c
@@ -1785,9 +1785,18 @@ int byte_strrstr(const uint8_t *src, size_t srclen, const uint8_t *pattern, size
 }
 
 void sb_append_char(smartbuf *sb, unsigned char c) {
+
     if (sb->idx >= sb->size) {
+
         sb->size *= 2;
-        sb->ptr = realloc(sb->ptr, sb->size);
+
+        void *tmp = realloc(sb->ptr, sb->size);
+        if (tmp == NULL) {
+            PrintAndLogEx(WARNING, "Failed to allocate memory");
+            return;
+        }
+
+        sb->ptr = tmp;
     }
     sb->ptr[sb->idx] = c;
     sb->idx++;