Re: [PATCH] NFSv4.1: Fix memory leakage

[Benjamin Coddington]

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@xxxxxxxxxx>
> ---
>  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