From 28457946df048e9e21c53c47dd3d31fad8494b37 Mon Sep 17 00:00:00 2001
From: Andrii Bilynskyi <andrii.bilynskyi@telink-semi.com>
Date: Mon, 10 Apr 2023 15:08:18 +0300
Subject: [PATCH] [Telink] Fix NotifyAdvertisingStopped with Null node

Since in file src/platform/Zephyr/BLEAdvertisingArbiter.cpp
function InsertRequest obtains previous node using iteration
via slist - condition (prev == nullptr) is only true if slist is
empty. In that case NotifyAdvertisingStopped is always called
with Null and no Null checker inside the function.
As result crash.
---
 src/platform/Zephyr/BLEAdvertisingArbiter.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/platform/Zephyr/BLEAdvertisingArbiter.cpp b/src/platform/Zephyr/BLEAdvertisingArbiter.cpp
index 29f55168f1c627..1e8ff7bb2e7501 100644
--- a/src/platform/Zephyr/BLEAdvertisingArbiter.cpp
+++ b/src/platform/Zephyr/BLEAdvertisingArbiter.cpp
@@ -90,7 +90,6 @@ CHIP_ERROR InsertRequest(Request & request)
 
     if (prev == nullptr)
     {
-        NotifyAdvertisingStopped(sys_slist_peek_head(&sRequests));
         sys_slist_prepend(&sRequests, &request);
     }
     else
@@ -110,6 +109,13 @@ CHIP_ERROR InsertRequest(Request & request)
 void CancelRequest(Request & request)
 {
     const bool isTopPriority = (sys_slist_peek_head(&sRequests) == &request);
+
+    // If cancelled request was top-priority, stop the advertising.
+    if (isTopPriority)
+    {
+        NotifyAdvertisingStopped(sys_slist_peek_head(&sRequests));
+    }
+
     VerifyOrReturn(sys_slist_find_and_remove(&sRequests, &request));
 
     // If cancelled request was top-priority, restart the advertising.