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Message-ID: <ad7673eb-ff0d-ce39-e05d-6af3be5ac68c@kernel.org>
Date:   Fri, 24 Jun 2022 09:12:52 -0600
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Subject: Re: [PATCH] ipv6/sit: fix ipip6_tunnel_get_prl when memory allocation
 fails
Content-Language: en-US
To:     zys.zljxml@gmail.com, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, yoshfuji@linux-ipv6.org
Cc:     kuba@kernel.org, davem@davemloft.net, edumazet@google.com,
        eric.dumazet@gmail.com, pabeni@redhat.com,
        katrinzhou <katrinzhou@tencent.com>
References: <20220624081254.1251316-1-zys.zljxml@gmail.com>
From:   David Ahern <dsahern@kernel.org>
In-Reply-To: <20220624081254.1251316-1-zys.zljxml@gmail.com>
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On 6/24/22 2:12 AM, zys.zljxml@gmail.com wrote:
> diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
> index c0b138c20992..4fb84c0b30be 100644
> --- a/net/ipv6/sit.c
> +++ b/net/ipv6/sit.c
> @@ -323,8 +323,6 @@ static int ipip6_tunnel_get_prl(struct net_device *dev, struct ip_tunnel_prl __u
>  		kcalloc(cmax, sizeof(*kp), GFP_KERNEL_ACCOUNT | __GFP_NOWARN) :
>  		NULL;
>  
> -	rcu_read_lock();
> -
>  	ca = min(t->prl_count, cmax);
>  
>  	if (!kp) {
> @@ -337,11 +335,12 @@ static int ipip6_tunnel_get_prl(struct net_device *dev, struct ip_tunnel_prl __u
>  					      __GFP_NOWARN);
>  		if (!kp) {
>  			ret = -ENOMEM;
> -			goto out;
> +			goto err;
>  		}
>  	}
>  
>  	c = 0;
> +	rcu_read_lock();
>  	for_each_prl_rcu(t->prl) {
>  		if (c >= cmax)
>  			break;
> @@ -362,7 +361,7 @@ static int ipip6_tunnel_get_prl(struct net_device *dev, struct ip_tunnel_prl __u
>  		ret = -EFAULT;
>  
>  	kfree(kp);
> -
> +err:
>  	return ret;
>  }
>  

'out' label is no longer used and should be removed.