Re: [PATCH v4] ping: Check return value of function 'ping_queue_rcv_skb'

[David Miller]

From: Zheng Yongjun <zhengyongjun3@xxxxxxxxxx>
Date: Tue, 8 Jun 2021 14:42:46 +0800

> --- a/net/ipv4/ping.c
> +++ b/net/ipv4/ping.c
> @@ -954,6 +954,7 @@ bool ping_rcv(struct sk_buff *skb)
>  	struct sock *sk;
>  	struct net *net = dev_net(skb->dev);
>  	struct icmphdr *icmph = icmp_hdr(skb);
> +	bool rc = false;
>  
>  	/* We assume the packet has already been checked by icmp_rcv */
>  
> @@ -968,14 +969,13 @@ bool ping_rcv(struct sk_buff *skb)
>  		struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
>  
>  		pr_debug("rcv on socket %p\n", sk);
> -		if (skb2)
> -			ping_queue_rcv_skb(sk, skb2);
> +		if (skb2 && !ping_queue_rcv_skb(sk, skb2))
> +			rc = true;
>  		sock_put(sk);
> -		return true;
>  	}
>  	pr_debug("no socket, dropping\n");
>  
> -	return false;
> +	return rc;

YOu have chsanged the control flowe in a way that this pr_debug() can be inaccurate.
It can print when we did find a socket.

Please fix this.

Thank you.