netdev - Re: [PATCH v4] ax25: Fix refcount imbalance on inbound connections

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Message-ID: <wq52rxvjp64uk65rhoh245d5immjll7lat6f6lmjbrc2cru6ej@wnronkmoqbyr>
Date: Fri, 24 May 2024 11:25:36 -0400
From: Lars Kellogg-Stedman <lars@...bit.com>
To: Dan Cross <crossd@...il.com>
Cc: Dan Carpenter <dan.carpenter@...aro.org>, 
	Duoming Zhou <duoming@....edu.cn>, linux-hams@...r.kernel.org, netdev@...r.kernel.org
Subject: Re: [PATCH v4] ax25: Fix refcount imbalance on inbound connections

On Thu, May 23, 2024 at 04:39:27PM GMT, Dan Cross wrote:
> On Thu, May 23, 2024 at 2:23 PM Dan Carpenter <dan.carpenter@...aro.org> wrote:
> > The problem is that accept() and ax25_release() are not mirrored pairs.

Right, but my in making this patch I wasn't thinking so much about
accept/ax25_release, which as you say are not necessarily a mirrored
pair...

> It seems clear that this will happen for sockets that have a ref on
> the device either via `bind` or via `accept`.

...but rather bind/accept, which *are*. The patch I've submitted gives
us equivalent behavior on the code paths for inbound and outbound
connections.

Without this change, the ax.25 subsystem is completely broken. Maybe we
can come up with a more correct fix down the road, or maybe we'll
refactor all the things, but I would prefer to return the subsystem to a
usable state while we figure that out.

-- 
Lars Kellogg-Stedman <lars@...bit.com> | larsks @ {irc,twitter,github}
http://blog.oddbit.com/                | N1LKS