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From:   =?UTF-8?B?5Lq/5LiA?= <teroincn@gmail.com>
Date:   Wed, 22 Apr 2020 10:50:20 +0800
Message-ID: <CANTwqXDJi1LuT1Q382R6qFHm7qMqx6My6aCR0pejNR8BqzFLKg@mail.gmail.com>
Subject: [BUG] fs: nsf: does there exist a memleak in function nfs4_run_open_task?
To:     trond.myklebust@hammerspace.com, anna.schumaker@netapp.com
Cc:     linux-nfs@vger.kernel.org
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Sender: linux-nfs-owner@vger.kernel.org
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Hi, all:
When reviewing the code of  nfs4_run_open_task, if the rpc_task start
failed, the opendata reference held from kref_get would not be
released even return to upper callers.
I'm wonder that does  there leak the opendata?

static int nfs4_run_open_task(struct nfs4_opendata *data, int isrecover)
{
      ...
      struct rpc_task_setup task_setup_data = {
      ...
.     callback_ops = &nfs4_open_ops,
.     callback_data = data,
      ...
      };
      int status;

      nfs4_init_sequence(&o_arg->seq_args, &o_res->seq_res, 1);
      kref_get(&data->kref);
      ...

     task = rpc_run_task(&task_setup_data);
     if (IS_ERR(task))
            return PTR_ERR(task);
     status = rpc_wait_for_completion_task(task);
    if (status != 0) {
           data->cancelled = true;
           smp_wmb();
     } else
          status = data->rpc_status;
     rpc_put_task(task);

     return status;
}

Best regards,

Lin Yi