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From:   Benjamin Coddington <bcodding@redhat.com>
To:     Konstantin Meskhidze <konstantin.meskhidze@huawei.com>
Cc:     trond.myklebust@hammerspace.com, anna@kernel.org,
        linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org,
        yusongping@huawei.com, hukeping@huawei.com, artem.kuzin@huawei.com
Subject: Re: [PATCH] NFSv4.1: Fix memory leakage
Date:   Fri, 09 Dec 2022 07:29:02 -0500
Message-ID: <5EDDEEF3-59C6-4297-9E55-3528E6E015FE@redhat.com>
In-Reply-To: <20221209021823.1232874-1-konstantin.meskhidze@huawei.com>
References: <20221209021823.1232874-1-konstantin.meskhidze@huawei.com>
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On 8 Dec 2022, at 21:18, Konstantin Meskhidze wrote:

> This commit fixes potential memory leakage of 'calldata' memory chunk
> in _nfs41_proc_sequence() function.
>
> Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@huawei.com>
> ---
>  fs/nfs/nfs4proc.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index 86ed5c0142c3..b7aa66167341 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -9416,8 +9416,10 @@ static struct rpc_task *_nfs41_proc_sequence(str=
uct nfs_client *clp,
>  	task_setup_data.callback_data =3D calldata;
>
>  	ret =3D rpc_run_task(&task_setup_data);
> -	if (IS_ERR(ret))
> +	if (IS_ERR(ret)) {
> +		kfree(calldata);
>  		goto out_err;
> +	}
>  	return ret;
>  out_put_clp:
>  	nfs_put_client(clp);
> -- =

> 2.25.1

Did you observe this leak, or find it by code inspecton?

I don't think there's a leak here because there's no way rpc_run_task() c=
an
return an error withouth also doing rpc_call_ops->rpc_release, which shou=
ld
free the calldata.

Ben