[PATCH] media: verisilicon: fix use after free bug in hantro_remove due to race condition

From: Ma Ke
Date: Fri Sep 15 2023 - 03:06:45 EST


In hantro_probe, vpu->watchdog_work is bound with hantro_watchdog function. In
hantro_end_prepare_run, it will started by schedule_delayed_work. If there is an
unfinished work in hantro_remove, there may be a race condition and trigger UAF
bug.

Signed-off-by: Ma Ke <make_ruc2021@xxxxxxx>
---
drivers/media/platform/verisilicon/hantro_drv.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/media/platform/verisilicon/hantro_drv.c b/drivers/media/platform/verisilicon/hantro_drv.c
index 423fc85d79ee..1a5b3a85c520 100644
--- a/drivers/media/platform/verisilicon/hantro_drv.c
+++ b/drivers/media/platform/verisilicon/hantro_drv.c
@@ -1187,6 +1187,7 @@ static void hantro_remove(struct platform_device *pdev)

v4l2_info(&vpu->v4l2_dev, "Removing %s\n", pdev->name);

+ cancel_delayed_work_sync(&vpu->watchdog_work);
media_device_unregister(&vpu->mdev);
hantro_remove_dec_func(vpu);
hantro_remove_enc_func(vpu);
--
2.37.2