From c7907994920aa8cea9e2d80fa6d4dd36ff6fe99b Mon Sep 17 00:00:00 2001
From: Shuai Wang <wang.lin.shuai@qq.com>
Date: Fri, 26 Jun 2026 09:56:12 +0800
Subject: [PATCH] fix(nimble): initialize return value in LED characteristic
 access callback

When the NimBLE stack called this callback for a GATT Write Request, the
uninitialized stack value was interpreted as a non-zero GATT error code,
causing the stack to send BLE_ATT_ERR_UNLIKELY (0x0E) back to the client.
---
 .../ble_get_started/nimble/NimBLE_GATT_Server/README.md      | 5 +----
 .../nimble/NimBLE_GATT_Server/main/src/gatt_svc.c            | 5 +----
 .../nimble/NimBLE_Security/main/src/gatt_svc.c               | 5 +----
 3 files changed, 3 insertions(+), 12 deletions(-)

diff --git a/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/README.md b/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/README.md
index 9be317a527c..37442fa97f0 100644
--- a/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/README.md
+++ b/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/README.md
@@ -169,9 +169,6 @@ The characteristic is binded with `led_chr_access` callback function, in which t
 ``` C
 static int led_chr_access(uint16_t conn_handle, uint16_t attr_handle,
                           struct ble_gatt_access_ctxt *ctxt, void *arg) {
-    /* Local variables */
-    int rc;
-
     /* Handle access events */
     /* Note: LED characteristic is write only */
     switch (ctxt->op) {
@@ -203,7 +200,7 @@ static int led_chr_access(uint16_t conn_handle, uint16_t attr_handle,
             } else {
                 goto error;
             }
-            return rc;
+            return 0;
         }
         goto error;
 
diff --git a/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/main/src/gatt_svc.c b/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/main/src/gatt_svc.c
index 4e521e348b5..bf03d4023f4 100644
--- a/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/main/src/gatt_svc.c
+++ b/examples/bluetooth/ble_get_started/nimble/NimBLE_GATT_Server/main/src/gatt_svc.c
@@ -114,9 +114,6 @@ error:
 
 static int led_chr_access(uint16_t conn_handle, uint16_t attr_handle,
                           struct ble_gatt_access_ctxt *ctxt, void *arg) {
-    /* Local variables */
-    int rc = 0;
-
     /* Handle access events */
     /* Note: LED characteristic is write only */
     switch (ctxt->op) {
@@ -148,7 +145,7 @@ static int led_chr_access(uint16_t conn_handle, uint16_t attr_handle,
             } else {
                 goto error;
             }
-            return rc;
+            return 0;
         }
         goto error;
 
diff --git a/examples/bluetooth/ble_get_started/nimble/NimBLE_Security/main/src/gatt_svc.c b/examples/bluetooth/ble_get_started/nimble/NimBLE_Security/main/src/gatt_svc.c
index d819be8e5be..726a4f2bb60 100644
--- a/examples/bluetooth/ble_get_started/nimble/NimBLE_Security/main/src/gatt_svc.c
+++ b/examples/bluetooth/ble_get_started/nimble/NimBLE_Security/main/src/gatt_svc.c
@@ -117,9 +117,6 @@ error:
 
 static int led_chr_access(uint16_t conn_handle, uint16_t attr_handle,
                           struct ble_gatt_access_ctxt *ctxt, void *arg) {
-    /* Local variables */
-    int rc = 0;
-
     /* Handle access events */
     /* Note: LED characteristic is write only */
     switch (ctxt->op) {
@@ -151,7 +148,7 @@ static int led_chr_access(uint16_t conn_handle, uint16_t attr_handle,
             } else {
                 goto error;
             }
-            return rc;
+            return 0;
         }
         goto error;