Merge branch 'bugfix/xStreamBufferReset_crashing_v4.3' into 'release/v4.3'

FreeRTOS: Fix xStreamBufferReset function always crashing (backport v4.3)

See merge request espressif/esp-idf!16171

components/freertos/stream_buffer.c

@@ -153,7 +153,10 @@ typedef struct StreamBufferDef_t /*lint !e9058 Style convention uses tag. */
 		UBaseType_t uxStreamBufferNumber;		/* Used for tracing purposes. */
 	#endif
 
-	portMUX_TYPE xStreamBufferMux;	//Mutex required due to SMP
+	#ifdef ESP_PLATFORM
+		/* Mutex required due to SMP. This field shall be the last one of the structure. */
+		portMUX_TYPE xStreamBufferMux;
+	#endif // ESP_PLATFORM
 } StreamBuffer_t;
 
 /*
@@ -214,6 +217,17 @@ static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
 										  size_t xTriggerLevelBytes,
 										  uint8_t ucFlags ) PRIVILEGED_FUNCTION;
 
+#ifdef ESP_PLATFORM
+/**
+ * Called by xStreamBufferReset() to reset the members of the StreamBuffer, excluding
+ * its spinlock.
+ */
+static void prvResetStreamBufferFields( StreamBuffer_t * const pxStreamBuffer,
+										uint8_t * const pucBuffer,
+										size_t xBufferSizeBytes,
+										size_t xTriggerLevelBytes,
+										uint8_t ucFlags ) PRIVILEGED_FUNCTION;
+#endif
 /*-----------------------------------------------------------*/
 
 #if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
@@ -423,11 +437,23 @@ BaseType_t xReturn = pdFAIL;
 		{
 			if( pxStreamBuffer->xTaskWaitingToSend == NULL )
 			{
+				#ifdef ESP_PLATFORM
+					/* As we just entered a critical section, we must NOT reset the spinlock field.
+					 * Thus, call `prvResetStreamBufferFields` instead of `prvInitialiseNewStreamBuffer`
+					 */
+					prvResetStreamBufferFields( pxStreamBuffer,
+												pxStreamBuffer->pucBuffer,
+												pxStreamBuffer->xLength,
+												pxStreamBuffer->xTriggerLevelBytes,
+												pxStreamBuffer->ucFlags );
+
+				#else  // ESP_PLATFORM
 					prvInitialiseNewStreamBuffer( pxStreamBuffer,
 												  pxStreamBuffer->pucBuffer,
 												  pxStreamBuffer->xLength,
 												  pxStreamBuffer->xTriggerLevelBytes,
 												  pxStreamBuffer->ucFlags );
+				#endif // ESP_PLATFORM
 				xReturn = pdPASS;
 
 				#if( configUSE_TRACE_FACILITY == 1 )
@@ -1241,6 +1267,43 @@ static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
 	vPortCPUInitializeMutex( &pxStreamBuffer->xStreamBufferMux );
 }
 
+
+#ifdef ESP_PLATFORM
+
+	/** The goal of this function is to (re)set all the fields of the given StreamBuffer, except
+	 * its lock.
+	 */
+	static void prvResetStreamBufferFields( StreamBuffer_t * const pxStreamBuffer,
+											uint8_t * const pucBuffer,
+											size_t xBufferSizeBytes,
+											size_t xTriggerLevelBytes,
+											uint8_t ucFlags )
+	{
+		#if ( configASSERT_DEFINED == 1 )
+			{
+				/* The value written just has to be identifiable when looking at the
+				* memory.  Don't use 0xA5 as that is the stack fill value and could
+				* result in confusion as to what is actually being observed. */
+				const BaseType_t xWriteValue = 0x55;
+				configASSERT( memset( pucBuffer, ( int ) xWriteValue, xBufferSizeBytes ) == pucBuffer );
+			} /*lint !e529 !e438 xWriteValue is only used if configASSERT() is defined. */
+		#endif
+
+		/* Do not include the spinlock in the part to reset!
+		 * Thus, make sure the spinlock is the last field of the structure. */
+		_Static_assert( offsetof(StreamBuffer_t, xStreamBufferMux) == sizeof( StreamBuffer_t ) - sizeof(portMUX_TYPE),
+						"xStreamBufferMux must be the last field of structure StreamBuffer_t" );
+		const size_t erasable = sizeof( StreamBuffer_t ) - sizeof(portMUX_TYPE);
+		( void ) memset( ( void * ) pxStreamBuffer, 0x00, erasable ); /*lint !e9087 memset() requires void *. */
+		pxStreamBuffer->pucBuffer = pucBuffer;
+		pxStreamBuffer->xLength = xBufferSizeBytes;
+		pxStreamBuffer->xTriggerLevelBytes = xTriggerLevelBytes;
+		pxStreamBuffer->ucFlags = ucFlags;
+	}
+
+#endif // ESP_PLATFORM
+
+
 #if ( configUSE_TRACE_FACILITY == 1 )
 
 	UBaseType_t uxStreamBufferGetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer )