Re: [tipc-discussion] [net-next] tipc: add NULL pointer check

[Jon M. <jon...@er...>]

Acked-by: Jon Maloy <jon...@er...>

Although "somehow" is not the good term here,- the reason is obvious when looking into tipc_sk_proto_rcv().


> -----Original Message-----
> From: net...@vg... <net...@vg...>
> On Behalf Of Hoang Le
> Sent: 3-Apr-19 02:05
> To: Jon Maloy <jon...@er...>; ma...@do...;
> yin...@wi...; tip...@li...;
> ne...@vg...
> Subject: [net-next] tipc: add NULL pointer check
> 
> skb somehow dequeued out of inputq before processing, it causes to NULL
> pointer and kernel crashed.
> 
> Add checking skb valid before using.
> 
> Fixes: c55c8edafa9 ("tipc: smooth change between replicast and broadcast")
> Reported-by: Tuong Lien Tong <tuo...@de...>
> Acked-by: Ying Xue <yin...@wi...>
> Signed-off-by: Hoang Le <hoa...@de...>
> ---
>  net/tipc/bcast.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c index
> 76e14dc08bb9..6c997d4a6218 100644
> --- a/net/tipc/bcast.c
> +++ b/net/tipc/bcast.c
> @@ -769,6 +769,9 @@ void tipc_mcast_filter_msg(struct net *net, struct
> sk_buff_head *defq,
>  	u32 node, port;
> 
>  	skb = skb_peek(inputq);
> +	if (!skb)
> +		return;
> +
>  	hdr = buf_msg(skb);
> 
>  	if (likely(!msg_is_syn(hdr) && skb_queue_empty(defq)))
> --
> 2.17.1