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 );
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
Best regards, Paweł Kubrak
Thank you for your feedback - this will be investigated and reported back.
As the DHCP code always runs from within the IP-task, I think it is safe to call the internal close function
Public API Internal call
FreeRTOS_DHCP.c, could you replace all occurrences of
vSocketClose() and see if that helps?
I just tried that myself and it works fine for me.