This is not the Heartbleed bug. I am not certain this is actually an immediately exploitable vulnerability (aka a sexy bug). What this looks like is an instance where the code calls free() on a buffer, then assumes the buffer is still available (uses it in some way). The patch seems to make it only free the buffer after it is empty, preventing this behavior. I think this is related to OpenSSL's issue with malloc and the way it handles memory allocation.
No this was written about a couple days ago. It frees the memory and because Open uses a LIFO memory allocater it can "safely" assume that whatever was still in there is still in there. I belive that in order to exploit this you would need to exhaust its internal allocator (so that it requests more from the OS) and your payoff would be... having your connection dropped.
This was discovered in the course of someone's attempt to figure out why OpenSSL randomly drops connections when its using a sane/OS supplied allocator.
