[PATCH] nvmet-tcp: don't restore null sk_state_change

[Alistair Francis]

On Wed, Apr 23, 2025 at 4:21 PM Hannes Reinecke <hare at suse.de> wrote:
>
> On 4/23/25 08:06, Alistair Francis wrote:
> > queue->state_change is set as part of nvmet_tcp_set_queue_sock(), but if
> > the TCP connection isn't established when nvmet_tcp_set_queue_sock() is
> > called then queue->state_change isn't set and sock->sk->sk_state_change
> > isn't replaced.
> >
> > As such we don't need to restore sock->sk->sk_state_change if
> > queue->state_change is NULL.
> >
> Good catch!
>
> [ .. ]
>
> > Resolves: https://lore.kernel.org/linux-nvme/5hdonndzoqa265oq3bj6iarwtfk5dewxxjtbjvn5uqnwclpwt6@a2n6w3taxxex/
> > Signed-off-by: Alistair Francis <alistair.francis at wdc.com>
> > ---
> > We could also remove the `sock->sk->sk_state != TCP_ESTABLISHED` check
> > in nvmet_tcp_set_queue_sock() if that's prefered.
> >
> Please do.
> We cannot influence what the network stack did, so if there ever were a
> modification which caused the ->state_change callback _not_ to be set
> the whole issue pops up again.

If queue->state_change isn't set for any other reason this patch
should also work, but I'll remove the `sock->sk->sk_state !=
TCP_ESTABLISHED` check as well

Alistair

>
> Cheers,
>
> Hannes
> --
> Dr. Hannes Reinecke                  Kernel Storage Architect
> hare at suse.de                                +49 911 74053 688
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