Re: [net 1/1] tipc: fix list sorting bug in function tipc_group_update_member()

[David Miller <davem@davemloft.net>]

From: Jon Maloy <jon.maloy@ericsson.com>
Date: Mon, 18 Dec 2017 20:03:05 +0100

> When, during a join operation, or during message transmission, a group
> member needs to be added to the group's 'congested' list, we sort it
> into the list in ascending order, according to its current advertised
> window size. However, we miss the case when the member is already on
> that list. This will have the result that the member, after the window
> size has been decremented, might be at the wrong position in that list.
> This again may have the effect that we during broadcast and multicast
> transmissions miss the fact that a destination is not yet ready for
> reception, and we end up sending anyway. From this point on, the
> behavior during the remaining session is unpredictable, e.g., with
> underflowing window sizes.
> 
> We now correct this bug by unconditionally removing the member from
> the list before (re-)sorting it in.
> 
> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>

Applied, thanks Jon.