peku33 wrote on Wednesday, August 10, 2016:
Hi.
I’m using FreeRTOS 9.0 / Labs TCP project. I discovered a possibility of race condition in process of binding / releasing socket.
The main issue is, that under higher system loads, the DHCP tasks likes to call
configASSERT( xReturn == 0 );
just after
xReturn = vSocketBind( xDHCPData.xDHCPSocket, &xAddress, sizeof( xAddress ), pdFALSE );
After investigation i found this is because of Address in use
problem.
This is (most likely) caused by delay between FreeRTOS_closesocket( xDHCPData.xDHCPSocket );
and actual freeing of bind in vSocketClose
(which is delayed to task).
Before the port is released, the DHCP socket is recreated and bind fails causing assertion to kill the system.
While I’m able to understand why releasing buffers is delayed, I’m not able to get why removing of bind isn’t done immediately.
Possible solution (but I’m not sure if there aren’t any other constraints) is to move uxListRemove( &( pxSocket->xBoundSocketListItem ) );
to FreeRTOS_closesocket
instead of vSocketClose
.
Best regards, Paweł Kubrak