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Date:   Fri, 7 Jul 2023 12:09:28 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Daniel Xu <dxu@dxuuu.xyz>
Cc:     pabeni@redhat.com, edumazet@google.com, kuba@kernel.org,
        fw@strlen.de, davem@davemloft.net, pablo@netfilter.org,
        kadlec@netfilter.org, dsahern@kernel.org, daniel@iogearbox.net,
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Subject: Re: [PATCH bpf-next v2 3/6] netfilter: bpf: Prevent defrag module
 unload while link active
Message-ID: <20230707100928.GA11622@breakpoint.cc>
References: <cover.1688685338.git.dxu@dxuuu.xyz>
 <81ede90e3f1468763ea5b0b6ec2971b7b1b870c1.1688685338.git.dxu@dxuuu.xyz>
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Daniel Xu <dxu@dxuuu.xyz> wrote:
> +		/* Prevent defrag module from going away while in use */
> +		if (!try_module_get(v4_hook->owner)) {
> +			err = -ENOENT;
> +			goto out_v4;
> +		}
> +
>  		err = v4_hook->enable(link->net);
>  out_v4:
>  		rcu_read_unlock();
> @@ -79,6 +86,12 @@ static int bpf_nf_enable_defrag(struct bpf_nf_link *link)
>  			}
>  		}
>  
> +		/* Prevent defrag module from going away while in use */
> +		if (!try_module_get(v6_hook->owner)) {
> +			err = -ENOENT;
> +			goto out_v6;
> +		}
> +
>  		err = v6_hook->enable(link->net);
>  out_v6:
>  		rcu_read_unlock();

This needs module_put() calls in case ->enable() returns an error, no?

Other than this this series LGTM, thanks!