linux-kernel - Re: [PATCH] NFSv4.1: Fix memory leakage

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 09 Dec 2022 07:29:02 -0500
From:   Benjamin Coddington <bcodding@...hat.com>
To:     Konstantin Meskhidze <konstantin.meskhidze@...wei.com>
Cc:     trond.myklebust@...merspace.com, anna@...nel.org,
        linux-kernel@...r.kernel.org, linux-nfs@...r.kernel.org,
        yusongping@...wei.com, hukeping@...wei.com, artem.kuzin@...wei.com
Subject: Re: [PATCH] NFSv4.1: Fix memory leakage

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@...wei.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(struct nfs_client *clp,
>  	task_setup_data.callback_data = calldata;
>
>  	ret = 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() can
return an error withouth also doing rpc_call_ops->rpc_release, which should
free the calldata.

Ben