Hello,
This v2 series fixes the use-after-free bug in mtk_jpeg_dec_device_run.
It inclues reverting the incomplete fix before and make the right fix.
Also,it fixes the error of timeout-worker-schedule in multiple-core
devices.
1. Remove cancel worker in mtk_jpeg_remove for the worker is only
registered in single-core device but we try to cacnel it in both
single-core and multiple-core devices.
2. Fix use-after-free bug by delay the schedule_delayed_work only if
mtk_jpeg_set_dec_dst runs successfully.
3. Delay the schedule_delayed_work in mtk_jpegdec_worker as it has same
code logic in mtk_jpeg_dec_device_run.
version 2 changes
-put the patches into on series suggested by Dmitry
Zheng Wang (3):
media: mtk-jpeg: Remove cancel worker in mtk_jpeg_remove to avoid the
crash of multi-core JPEG devices
media: mtk-jpeg: Fix use after free bug due to error path handling
in mtk_jpeg_dec_device_run
media: mtk-jpeg: Fix timeout schedule error in mtk_jpegdec_worker.
.../media/platform/mediatek/jpeg/mtk_jpeg_core.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
--
2.25.1
This patch reverts commit c677d7ae8314
("media: mtk-jpeg: Fix use after free bug due to uncanceled work").
The job_timeout_work is initialized only for
the single-core JPEG device so it will cause the crash for multi-core
JPEG devices.
Fix it by removing the cancel_delayed_work_sync function.
Fixes: c677d7ae8314 ("media: mtk-jpeg: Fix use after free bug due to uncanceled work")
Signed-off-by: Zheng Wang <[email protected]>
Signed-off-by: Dmitry Osipenko <[email protected]>
---
v2:
- put the patches into a single series suggested by Dmitry
---
drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 7194f88edc0f..60425c99a2b8 100644
--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
@@ -1403,7 +1403,6 @@ 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);
--
2.25.1
In mtk_jpeg_probe, &jpeg->job_timeout_work is bound with
mtk_jpeg_job_timeout_work.
In mtk_jpeg_dec_device_run, if error happens in
mtk_jpeg_set_dec_dst, it will finally start the worker while
mark the job as finished by invoking v4l2_m2m_job_finish.
There are two methods to trigger the bug. If we remove the
module, it which will call mtk_jpeg_remove to make cleanup.
The possible sequence is as follows, which will cause a
use-after-free bug.
CPU0 CPU1
mtk_jpeg_dec_... |
start worker |
|mtk_jpeg_job_timeout_work
mtk_jpeg_remove |
v4l2_m2m_release |
kfree(m2m_dev); |
|
| v4l2_m2m_get_curr_priv
| m2m_dev->curr_ctx //use
If we close the file descriptor, which will call mtk_jpeg_release,
it will have a similar sequence.
Fix this bug by starting timeout worker only if started jpegdec worker
successfully. Then v4l2_m2m_job_finish will only be called in
either mtk_jpeg_job_timeout_work or mtk_jpeg_dec_device_run.
Fixes: b2f0d2724ba4 ("[media] vcodec: mediatek: Add Mediatek JPEG Decoder Driver")
Signed-off-by: Zheng Wang <[email protected]>
Signed-off-by: Dmitry Osipenko <[email protected]>
Cc: [email protected]
---
v2:
- put the patches into a single series suggested by Dmitry
---
drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 60425c99a2b8..a39acde2724a 100644
--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
@@ -1021,13 +1021,13 @@ static void mtk_jpeg_dec_device_run(void *priv)
if (ret < 0)
goto dec_end;
- schedule_delayed_work(&jpeg->job_timeout_work,
- msecs_to_jiffies(MTK_JPEG_HW_TIMEOUT_MSEC));
-
mtk_jpeg_set_dec_src(ctx, &src_buf->vb2_buf, &bs);
if (mtk_jpeg_set_dec_dst(ctx, &jpeg_src_buf->dec_param, &dst_buf->vb2_buf, &fb))
goto dec_end;
+ schedule_delayed_work(&jpeg->job_timeout_work,
+ msecs_to_jiffies(MTK_JPEG_HW_TIMEOUT_MSEC));
+
spin_lock_irqsave(&jpeg->hw_lock, flags);
mtk_jpeg_dec_reset(jpeg->reg_base);
mtk_jpeg_dec_set_config(jpeg->reg_base,
--
2.25.1