Subject: Re: [PATCH net v2] netrom: fix sleep in atomic context bugs in timer handlers

From: Jakub Kicinski <[email-masked]>
Date: Wed, 27 Jul 2022 18:36:47 -0700

On Tue, 26 Jul 2022 11:24:20 +0800 Duoming Zhou wrote:
> nr_heartbeat_expiry
>   nr_write_internal
>     nr_transmit_buffer

void nr_transmit_buffer(struct sock *sk, struct sk_buff *skb)
{
[...]
	if (!nr_route_frame(skb, NULL)) {

>       nr_route_frame

int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
{
[...]
	if (ax25 != NULL) {
		ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,

ax25 must be NULL on this path AFAICT.

>         nr_add_node
>           kmemdup(..,GFP_KERNEL) //may sleep