From 083a5a7b78209aabf6365003e4cfd463b6b00c0f Mon Sep 17 00:00:00 2001
From: Amine Alami <43780877+Alami-Amine@users.noreply.github.com>
Date: Mon, 23 Sep 2024 19:09:55 +0200
Subject: [PATCH] Bugfix: packet buffer counter going negative and triggering
 UBSan Issue (#35708)

* Fix for issue where the packet buffer counter (sResourcesInUse[kSystemLayer_NumPacketBufs]) in SystemStats is going negative and underflowing, triggering a UBSan issue during fuzzing

* Integrating comments
---
 src/system/SystemPacketBuffer.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/system/SystemPacketBuffer.cpp b/src/system/SystemPacketBuffer.cpp
index 20bd93540afe62..79e1bd25a67d8a 100644
--- a/src/system/SystemPacketBuffer.cpp
+++ b/src/system/SystemPacketBuffer.cpp
@@ -151,6 +151,8 @@ void PacketBufferHandle::InternalRightSize()
         return;
     }
 
+    SYSTEM_STATS_INCREMENT(chip::System::Stats::kSystemLayer_NumPacketBufs);
+
     uint8_t * const newStart = newBuffer->ReserveStart();
     newBuffer->next          = nullptr;
     newBuffer->payload       = newStart + (payload - start);