OS_TaskExit() on VxWorks causes task table owner to be the deleted task

[johnphamngc]

Describe the bug
OS_TaskExit() calls OS_ObjectIdFinalizeDelete(). This function sets the task's record->active_id to 0, which is also being used as the task ID on VxWorks. ObjectIdFinalizeDelete() subsequently calls OS_Unlock_Global, which errors out and does not clear the owner, as the task ID is now zeroed out and does not match the owner of the table. This does not occur on Linux

To Reproduce
Steps to reproduce the behavior:
On VxWorks, call CFE_ES_ExitChildTask with OSAL_CONFIG_DEBUG_PRINTF enabled

Expected behavior
Error message should not be printed out

Code snips

osal/src/os/shared/src/osapi-idmap.c

Lines 745 to 777 in 1a82657

	/*----------------------------------------------------------------
	Function: OS_ObjectIdFinalizeDelete
	Purpose: Helper routine, not part of OSAL public API.
	See description in prototype
	------------------------------------------------------------------*/
	int32 OS_ObjectIdFinalizeDelete(int32 operation_status, OS_common_record_t *record)
	{
	uint32 idtype = OS_ObjectIdToType_Impl(record->active_id);
	osal_id_t callback_id;
	/* Clear the OSAL ID if successful - this returns the record to the pool */
	if (operation_status == OS_SUCCESS)
	{
	callback_id = record->active_id;
	record->active_id = OS_OBJECT_ID_UNDEFINED;
	}
	else
	{
	callback_id = OS_OBJECT_ID_UNDEFINED;
	}
	/* Either way we must unlock the object type */
	OS_Unlock_Global(idtype);
	/* Give event callback to the application */
	if (OS_ObjectIdDefined(callback_id))
	{
	OS_NotifyEvent(OS_EVENT_RESOURCE_DELETED, callback_id, NULL);
	}
	return operation_status;
	}

osal/src/os/shared/src/osapi-idmap.c

Lines 625 to 676 in 1a82657

	void OS_Unlock_Global(uint32 idtype)
	{
	int32 return_code;
	osal_id_t self_task_id;
	OS_objtype_state_t *objtype;
	if (idtype < OS_OBJECT_TYPE_USER)
	{
	objtype = &OS_objtype_state[idtype];
	self_task_id = OS_TaskGetId_Impl();
	/*
	* Un-track ownership of this table. It should only be owned by one
	* task at a time, and this aids in recovery if the owning task is
	* deleted or experiences an exception causing it to not be freed.
	*
	* This is done before unlocking, while this has exclusive access
	* to the state object.
	*/
	if (!OS_ObjectIdDefined(self_task_id))
	{
	/*
	* This just means the calling context is not an OSAL-created task.
	* This is not necessarily an error, but it should be tracked.
	* Also note that the root/initial task also does not have an ID.
	*/
	self_task_id = OS_OBJECT_ID_RESERVED; /* nonzero, but also won't alias a known task */
	}
	if (!OS_ObjectIdEqual(objtype->table_owner, self_task_id))
	{
	/* this is almost certainly a bug */
	OS_DEBUG("ERROR: global %u released by task 0x%lx when owned by task 0x%lx\n", (unsigned int)idtype,
	OS_ObjectIdToInteger(self_task_id), OS_ObjectIdToInteger(objtype->table_owner));
	}
	else
	{
	objtype->table_owner = OS_OBJECT_ID_UNDEFINED;
	}
	return_code = OS_Unlock_Global_Impl(idtype);
	}
	else
	{
	return_code = OS_ERR_INCORRECT_OBJ_TYPE;
	}
	if (return_code != OS_SUCCESS)
	{
	OS_DEBUG("ERROR: unable to unlock global %u, error=%d\n", (unsigned int)idtype, (int)return_code);
	}
	}

osal/src/os/vxworks/src/os-impl-tasks.c

Lines 385 to 413 in 1a82657

	/*----------------------------------------------------------------
	*
	* Function: OS_TaskGetId_Impl
	*
	* Purpose: Implemented per internal OSAL API
	* See prototype for argument/return detail
	*
	*-----------------------------------------------------------------*/
	osal_id_t OS_TaskGetId_Impl(void)
	{
	OS_impl_task_internal_record_t *lrec;
	size_t index;
	osal_id_t id;
	id = OS_OBJECT_ID_UNDEFINED;
	lrec = (OS_impl_task_internal_record_t *)taskTcb(taskIdSelf());
	if (lrec != NULL)
	{
	index = lrec - &OS_impl_task_table[0];
	if (index < OS_MAX_TASKS)
	{
	id = OS_global_task_table[index].active_id;
	}
	}
	return id;
	} /* end OS_TaskGetId_Impl */

osal/src/os/posix/src/os-impl-tasks.c

Lines 736 to 751 in 1a82657

	/*----------------------------------------------------------------
	*
	* Function: OS_TaskGetId_Impl
	*
	* Purpose: Implemented per internal OSAL API
	* See prototype for argument/return detail
	*
	*-----------------------------------------------------------------*/
	osal_id_t OS_TaskGetId_Impl(void)
	{
	OS_U32ValueWrapper_t self_record;
	self_record.opaque_arg = pthread_getspecific(POSIX_GlobalVars.ThreadKey);
	return (self_record.id);
	} /* end OS_TaskGetId_Impl */

System observed on:

• SP0
• OS: VxWorks 6.9
• Versions: CFE 6.8, OSAL 5.1.0-rc1+dev16,

Additional context
See attached screenshots for stack traces


Reporter Info
John N. Pham, Northrop Grumman

[jphickey]

Although the tickets don't seem related, what I'm working on for #642 will likely implement a process where the deleted task record is only "marked" as deleted but keeps its ID valid while it waits for the task to actually exit.

So - it should fix this too, because the ID in the global record will still be valid when the unlocking is done.