| Message ID | 1591718228-18819-1-git-send-email-gubbaven@codeaurora.org (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Marcel Holtmann |
| Headers | show |
| Series | [v2] Bluetooth: hci_qca: Bug fix during SSR timeout | expand |
Looks good to me. Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org> On Tue, Jun 9, 2020 at 8:57 AM Venkata Lakshmi Narayana Gubba <gubbaven@codeaurora.org> wrote: > > 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> > --- > 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 28c34a1..f3fde99 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; > } > @@ -1483,8 +1486,6 @@ 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_HW_ERROR_EVENT, &qca->flags); > bt_dev_info(hdev, "mem_dump_status: %d", qca->memdump_state); > @@ -1507,19 +1508,23 @@ 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); > -- > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member > of Code Aurora Forum, hosted by The Linux Foundation >
Hi Venkata, > 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> > --- > drivers/bluetooth/hci_qca.c | 29 +++++++++++++++++------------ > 1 file changed, 17 insertions(+), 12 deletions(-) patch has been applied to bluetooth-next tree. Regards Marcel
diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index 28c34a1..f3fde99 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; } @@ -1483,8 +1486,6 @@ 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_HW_ERROR_EVENT, &qca->flags); bt_dev_info(hdev, "mem_dump_status: %d", qca->memdump_state); @@ -1507,19 +1508,23 @@ 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);
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> --- drivers/bluetooth/hci_qca.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-)