lkml.org 
[lkml]   [2020]   [Aug]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.7 138/393] Bluetooth: hci_qca: Bug fix during SSR timeout
    Date
    From: Venkata Lakshmi Narayana Gubba <gubbaven@codeaurora.org>

    [ Upstream commit f98aa80ff78c34fe328eb9cd3e2cc3058e42bcfd ]

    Due to race conditions between qca_hw_error and qca_controller_memdump
    during SSR timeout,the same pointer is freed twice. This results in a
    double free. Now a lock is acquired before checking the stauts of SSR
    state.

    Fixes: d841502c79e3 ("Bluetooth: hci_qca: Collect controller memory dump during SSR")
    Signed-off-by: Venkata Lakshmi Narayana Gubba <gubbaven@codeaurora.org>
    Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
    Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/bluetooth/hci_qca.c | 29 +++++++++++++++++------------
    1 file changed, 17 insertions(+), 12 deletions(-)

    diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
    index dc949592c4ed5..a6dd13a2975a8 100644
    --- a/drivers/bluetooth/hci_qca.c
    +++ b/drivers/bluetooth/hci_qca.c
    @@ -981,8 +981,11 @@ static void qca_controller_memdump(struct work_struct *work)
    while ((skb = skb_dequeue(&qca->rx_memdump_q))) {

    mutex_lock(&qca->hci_memdump_lock);
    - /* Skip processing the received packets if timeout detected. */
    - if (qca->memdump_state == QCA_MEMDUMP_TIMEOUT) {
    + /* Skip processing the received packets if timeout detected
    + * or memdump collection completed.
    + */
    + if (qca->memdump_state == QCA_MEMDUMP_TIMEOUT ||
    + qca->memdump_state == QCA_MEMDUMP_COLLECTED) {
    mutex_unlock(&qca->hci_memdump_lock);
    return;
    }
    @@ -1451,8 +1454,6 @@ static void qca_hw_error(struct hci_dev *hdev, u8 code)
    {
    struct hci_uart *hu = hci_get_drvdata(hdev);
    struct qca_data *qca = hu->priv;
    - struct qca_memdump_data *qca_memdump = qca->qca_memdump;
    - char *memdump_buf = NULL;

    set_bit(QCA_SSR_TRIGGERED, &qca->flags);
    set_bit(QCA_HW_ERROR_EVENT, &qca->flags);
    @@ -1476,19 +1477,23 @@ static void qca_hw_error(struct hci_dev *hdev, u8 code)
    qca_wait_for_dump_collection(hdev);
    }

    + mutex_lock(&qca->hci_memdump_lock);
    if (qca->memdump_state != QCA_MEMDUMP_COLLECTED) {
    bt_dev_err(hu->hdev, "clearing allocated memory due to memdump timeout");
    - mutex_lock(&qca->hci_memdump_lock);
    - if (qca_memdump)
    - memdump_buf = qca_memdump->memdump_buf_head;
    - vfree(memdump_buf);
    - kfree(qca_memdump);
    - qca->qca_memdump = NULL;
    + if (qca->qca_memdump) {
    + vfree(qca->qca_memdump->memdump_buf_head);
    + kfree(qca->qca_memdump);
    + qca->qca_memdump = NULL;
    + }
    qca->memdump_state = QCA_MEMDUMP_TIMEOUT;
    cancel_delayed_work(&qca->ctrl_memdump_timeout);
    - skb_queue_purge(&qca->rx_memdump_q);
    - mutex_unlock(&qca->hci_memdump_lock);
    + }
    + mutex_unlock(&qca->hci_memdump_lock);
    +
    + if (qca->memdump_state == QCA_MEMDUMP_TIMEOUT ||
    + qca->memdump_state == QCA_MEMDUMP_COLLECTED) {
    cancel_work_sync(&qca->ctrl_memdump_evt);
    + skb_queue_purge(&qca->rx_memdump_q);
    }

    clear_bit(QCA_HW_ERROR_EVENT, &qca->flags);
    --
    2.25.1


    \
     
     \ /
      Last update: 2020-08-17 21:03    [W:4.626 / U:1.036 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site