From c677d7ae83141d390d1253abebafa49c962afb52 Mon Sep 17 00:00:00 2001
From: Zheng Wang <zyytlz.wz@163.com>
Date: Fri, 7 Jul 2023 17:24:14 +0800
Subject: [PATCH] media: mtk-jpeg: Fix use after free bug due to uncanceled work
Git-commit: c677d7ae83141d390d1253abebafa49c962afb52
Patch-mainline: v6.6-rc1
References: git-fixes
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@163.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 40cb3cb87ba1..621038aab116 100644
--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
@@ -1403,6 +1403,7 @@ static void mtk_jpeg_remove(struct platform_device *pdev)
{
struct mtk_jpeg_dev *jpeg = platform_get_drvdata(pdev);
+ cancel_delayed_work_sync(&jpeg->job_timeout_work);
pm_runtime_disable(&pdev->dev);
video_unregister_device(jpeg->vdev);
v4l2_m2m_release(jpeg->m2m_dev);
--
2.35.3