Received-SPF: pass (google.com: domain of linux-bluetooth-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230109012651.3127529-1-shaozhengchao@huawei.com>
In-Reply-To: <20230109012651.3127529-1-shaozhengchao@huawei.com>
From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date:   Mon, 9 Jan 2023 13:11:45 -0800
Message-ID: <CABBYNZK=GXHO3QrEF2ZXWohnYkyPsfo0K9ZPxe0aMK_wuK1myQ@mail.gmail.com>
Subject: Re: [PATCH] Bluetooth: hci_sync: fix memory leak in hci_update_adv_data()
To:     Zhengchao Shao <shaozhengchao@huawei.com>
Cc:     linux-bluetooth@vger.kernel.org, netdev@vger.kernel.org,
        marcel@holtmann.org, johan.hedberg@gmail.com, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        brian.gix@intel.com, weiyongjun1@huawei.com, yuehaibing@huawei.com
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hi Zhengchao,

On Sun, Jan 8, 2023 at 5:17 PM Zhengchao Shao <shaozhengchao@huawei.com> wrote:
>
> When hci_cmd_sync_queue() failed in hci_update_adv_data(), inst_ptr is
> not freed, which will cause memory leak. Add release process to error
> path.
>
> Fixes: 651cd3d65b0f ("Bluetooth: convert hci_update_adv_data to hci_sync")
> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
> ---
>  net/bluetooth/hci_sync.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 9e2d7e4b850c..1485501bd72f 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -6197,10 +6197,15 @@ static int _update_adv_data_sync(struct hci_dev *hdev, void *data)
>  int hci_update_adv_data(struct hci_dev *hdev, u8 instance)
>  {
>         u8 *inst_ptr = kmalloc(1, GFP_KERNEL);
> +       int ret;
>
>         if (!inst_ptr)
>                 return -ENOMEM;
>
>         *inst_ptr = instance;
> -       return hci_cmd_sync_queue(hdev, _update_adv_data_sync, inst_ptr, NULL);
> +       ret = hci_cmd_sync_queue(hdev, _update_adv_data_sync, inst_ptr, NULL);
> +       if (ret)
> +               kfree(inst_ptr);
> +
> +       return ret;
>  }

While this is correct I do wonder why we haven't used ERR_PTR/PTR_ERR
like we did with the likes of abort_conn_sync, that way we don't have
to allocate anything which makes things a lot simpler.

> --
> 2.34.1
>


-- 
Luiz Augusto von Dentz