Incorrect check of status from CFE_SB_ReceiveBuffer()

[jphickey]

Checking of the status return from this CFE API call is not correct/sufficient:

CF/fsw/src/cf_cfdp.c

Lines 1365 to 1369 in 7b99b91

	status = CFE_SB_ReceiveBuffer(&CF_AppData.engine.in.msg, c->pipe, CFE_SB_POLL);
	if (status == CFE_SB_NO_MESSAGE)
	{
	break; /* no more messages */
	}

This function may fail for a number of reasons, not limited to CFE_SB_NO_MESSAGE.

The preferred check should be:

if (status != CFE_SUCCESS)

[jphickey]

Note that if this fails for one of the other reasons, the output pointer is not set to a valid buffer. But CF code will proceed to access the (uninitialized) buffer, so this is a risk of undefined behavior/segfault/etc.