Messages in this thread Patch in this message | | | From | Zheng Wang <> | Subject | [PATCH v2] media: venus: fix use after free bug in venus_remove due to race condition | Date | Thu, 13 Apr 2023 16:06:53 +0800 |
| |
in venus_probe, core->work is bound with venus_sys_error_handler, which is used to handle error. The code use core->sys_err_done to make sync work. The core->work is started in venus_event_notify.
If we call venus_remove, there might be an unfished work. The possible sequence is as follows:
CPU0 CPU1
|venus_sys_error_handler venus_remove | hfi_destroy | venus_hfi_destroy | kfree(hdev); | |hfi_reinit |venus_hfi_queues_reinit |//use hdev
Fix it by canceling the work in venus_remove.
Fixes: af2c3834c8ca ("[media] media: venus: adding core part and helper functions") Signed-off-by: Zheng Wang <zyytlz.wz@163.com> --- v2: - add more details to clarify the bug --- drivers/media/platform/qcom/venus/core.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c index 990a1519f968..54ace8bf45e7 100644 --- a/drivers/media/platform/qcom/venus/core.c +++ b/drivers/media/platform/qcom/venus/core.c @@ -423,6 +423,7 @@ static int venus_remove(struct platform_device *pdev) struct device *dev = core->dev; int ret; + cancel_delayed_work(&core->work); ret = pm_runtime_get_sync(dev); WARN_ON(ret < 0); -- 2.25.1
| |