This is a security bug that has been reported to google.
It affected all platforms on chrome-os. Please apply this
patch to 5.10.
Due to the directory structure change, the file path to
be be patched is different from that in upstream.
[ Upstream commit c677d7ae83141d390d1253abebafa49c962afb52 ]
In mtk_jpeg_probe, &jpeg->job_timeout_work is bound with
mtk_jpeg_job_timeout_work. Then mtk_jpeg_dec_device_run
and mtk_jpeg_enc_device_run may be called to start the
work.
If we remove the module which will call mtk_jpeg_remove
to make cleanup, there may be a unfinished work. The
possible sequence is as follows, which will cause a
typical UAF bug.
Fix it by canceling the work before cleanup in the mtk_jpeg_remove
CPU0 CPU1
|mtk_jpeg_job_timeout_work
mtk_jpeg_remove |
v4l2_m2m_release |
kfree(m2m_dev); |
|
| v4l2_m2m_get_curr_priv
| m2m_dev->curr_ctx //use
Fixes: b2f0d2724ba4 ("[media] vcodec: mediatek: Add Mediatek JPEG Decoder Driver")
Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx>
Reviewed-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx>
Reviewed-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c b/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c
index ee802fc3bcdf..67c9ca4cfcd2 100644
--- a/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c
@@ -1189,6 +1189,7 @@ static int mtk_jpeg_remove(struct platform_device *pdev)
{
struct mtk_jpeg_dev *jpeg = platform_get_drvdata(pdev);
+ ancel_delayed_work_sync(&jpeg->job_timeout_work);
pm_runtime_disable(&pdev->dev);
video_unregister_device(jpeg->dec_vdev);
video_device_release(jpeg->dec_vdev);
--
2.25.1
