2024-02-22 09:26:47

by Yunfei Dong

[permalink] [raw]
Subject: [PATCH v3,2/2] media: mediatek: vcodec: adding lock to protect encoder context list

The ctx_list will be deleted when scp getting unexpected behavior, then the
ctx_list->next will be NULL, the kernel driver maybe access NULL pointer in
function vpu_enc_ipi_handler when going through each context, then reboot.

Need to add lock to protect the ctx_list to make sure the ctx_list->next isn't
NULL pointer.

Fixes: 1972e32431ed ("media: mediatek: vcodec: Fix possible invalid memory access for encoder")
Signed-off-by: Yunfei Dong <[email protected]>
---
.../platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c | 4 ++--
.../platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c | 5 +++++
.../platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h | 2 ++
drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c | 2 ++
4 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c b/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
index 9a11a2c248045..8d578b6902148 100644
--- a/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
+++ b/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
@@ -73,12 +73,12 @@ static void mtk_vcodec_vpu_reset_enc_handler(void *priv)

dev_err(&dev->plat_dev->dev, "Watchdog timeout!!");

- mutex_lock(&dev->dev_mutex);
+ mutex_lock(&dev->dev_ctx_lock);
list_for_each_entry(ctx, &dev->ctx_list, list) {
ctx->state = MTK_STATE_ABORT;
mtk_v4l2_vdec_dbg(0, ctx, "[%d] Change to state MTK_STATE_ABORT", ctx->id);
}
- mutex_unlock(&dev->dev_mutex);
+ mutex_unlock(&dev->dev_ctx_lock);
}

static const struct mtk_vcodec_fw_ops mtk_vcodec_vpu_msg = {
diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
index 5db2bf3db4c54..29524cd59ce8b 100644
--- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
+++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
@@ -177,7 +177,9 @@ static int fops_vcodec_open(struct file *file)
mtk_v4l2_venc_dbg(2, ctx, "Create instance [%d]@%p m2m_ctx=%p ",
ctx->id, ctx, ctx->m2m_ctx);

+ mutex_lock(&dev->dev_ctx_lock);
list_add(&ctx->list, &dev->ctx_list);
+ mutex_unlock(&dev->dev_ctx_lock);

mutex_unlock(&dev->dev_mutex);
mtk_v4l2_venc_dbg(0, ctx, "%s encoder [%d]", dev_name(&dev->plat_dev->dev),
@@ -212,7 +214,9 @@ static int fops_vcodec_release(struct file *file)
v4l2_fh_exit(&ctx->fh);
v4l2_ctrl_handler_free(&ctx->ctrl_hdl);

+ mutex_lock(&dev->dev_ctx_lock);
list_del_init(&ctx->list);
+ mutex_unlock(&dev->dev_ctx_lock);
kfree(ctx);
mutex_unlock(&dev->dev_mutex);
return 0;
@@ -294,6 +298,7 @@ static int mtk_vcodec_probe(struct platform_device *pdev)

mutex_init(&dev->enc_mutex);
mutex_init(&dev->dev_mutex);
+ mutex_init(&dev->dev_ctx_lock);
spin_lock_init(&dev->irqlock);

snprintf(dev->v4l2_dev.name, sizeof(dev->v4l2_dev.name), "%s",
diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
index a042f607ed8d1..0bd85d0fb379a 100644
--- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
+++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
@@ -178,6 +178,7 @@ struct mtk_vcodec_enc_ctx {
*
* @enc_mutex: encoder hardware lock.
* @dev_mutex: video_device lock
+ * @dev_ctx_lock: the lock of context list
* @encode_workqueue: encode work queue
*
* @enc_irq: h264 encoder irq resource
@@ -205,6 +206,7 @@ struct mtk_vcodec_enc_dev {
/* encoder hardware mutex lock */
struct mutex enc_mutex;
struct mutex dev_mutex;
+ struct mutex dev_ctx_lock;
struct workqueue_struct *encode_workqueue;

int enc_irq;
diff --git a/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c b/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
index 84ad1cc6ad171..51bb7ee141b9e 100644
--- a/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
+++ b/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
@@ -47,12 +47,14 @@ static bool vpu_enc_check_ap_inst(struct mtk_vcodec_enc_dev *enc_dev, struct ven
struct mtk_vcodec_enc_ctx *ctx;
int ret = false;

+ mutex_lock(&enc_dev->dev_ctx_lock);
list_for_each_entry(ctx, &enc_dev->ctx_list, list) {
if (!IS_ERR_OR_NULL(ctx) && ctx->vpu_inst == vpu) {
ret = true;
break;
}
}
+ mutex_unlock(&enc_dev->dev_ctx_lock);

return ret;
}
--
2.18.0



Subject: Re: [PATCH v3,2/2] media: mediatek: vcodec: adding lock to protect encoder context list

Il 22/02/24 10:26, Yunfei Dong ha scritto:
> The ctx_list will be deleted when scp getting unexpected behavior, then the
> ctx_list->next will be NULL, the kernel driver maybe access NULL pointer in
> function vpu_enc_ipi_handler when going through each context, then reboot.
>
> Need to add lock to protect the ctx_list to make sure the ctx_list->next isn't
> NULL pointer.
>
> Fixes: 1972e32431ed ("media: mediatek: vcodec: Fix possible invalid memory access for encoder")
> Signed-off-by: Yunfei Dong <[email protected]>

Reviewed-by: AngeloGioacchino Del Regno <[email protected]>


2024-02-23 18:12:07

by Nicolas Dufresne

[permalink] [raw]
Subject: Re: [PATCH v3,2/2] media: mediatek: vcodec: adding lock to protect encoder context list

Le jeudi 22 février 2024 à 17:26 +0800, Yunfei Dong a écrit :
> The ctx_list will be deleted when scp getting unexpected behavior, then the
> ctx_list->next will be NULL, the kernel driver maybe access NULL pointer in
> function vpu_enc_ipi_handler when going through each context, then reboot.
>
> Need to add lock to protect the ctx_list to make sure the ctx_list->next isn't
> NULL pointer.
>
> Fixes: 1972e32431ed ("media: mediatek: vcodec: Fix possible invalid memory access for encoder")
> Signed-off-by: Yunfei Dong <[email protected]>

Reviewed-by: Nicolas Dufresne <[email protected]>

> ---
> .../platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c | 4 ++--
> .../platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c | 5 +++++
> .../platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h | 2 ++
> drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c | 2 ++
> 4 files changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c b/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
> index 9a11a2c248045..8d578b6902148 100644
> --- a/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
> +++ b/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
> @@ -73,12 +73,12 @@ static void mtk_vcodec_vpu_reset_enc_handler(void *priv)
>
> dev_err(&dev->plat_dev->dev, "Watchdog timeout!!");
>
> - mutex_lock(&dev->dev_mutex);
> + mutex_lock(&dev->dev_ctx_lock);
> list_for_each_entry(ctx, &dev->ctx_list, list) {
> ctx->state = MTK_STATE_ABORT;
> mtk_v4l2_vdec_dbg(0, ctx, "[%d] Change to state MTK_STATE_ABORT", ctx->id);
> }
> - mutex_unlock(&dev->dev_mutex);
> + mutex_unlock(&dev->dev_ctx_lock);
> }
>
> static const struct mtk_vcodec_fw_ops mtk_vcodec_vpu_msg = {
> diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drvc
> index 5db2bf3db4c54..29524cd59ce8b 100644
> --- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
> +++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
> @@ -177,7 +177,9 @@ static int fops_vcodec_open(struct file *file)
> mtk_v4l2_venc_dbg(2, ctx, "Create instance [%d]@%p m2m_ctx=%p ",
> ctx->id, ctx, ctx->m2m_ctx);
>
> + mutex_lock(&dev->dev_ctx_lock);
> list_add(&ctx->list, &dev->ctx_list);
> + mutex_unlock(&dev->dev_ctx_lock);
>
> mutex_unlock(&dev->dev_mutex);
> mtk_v4l2_venc_dbg(0, ctx, "%s encoder [%d]", dev_name(&dev->plat_dev->dev),
> @@ -212,7 +214,9 @@ static int fops_vcodec_release(struct file *file)
> v4l2_fh_exit(&ctx->fh);
> v4l2_ctrl_handler_free(&ctx->ctrl_hdl);
>
> + mutex_lock(&dev->dev_ctx_lock);
> list_del_init(&ctx->list);
> + mutex_unlock(&dev->dev_ctx_lock);
> kfree(ctx);
> mutex_unlock(&dev->dev_mutex);
> return 0;
> @@ -294,6 +298,7 @@ static int mtk_vcodec_probe(struct platform_device *pdev)
>
> mutex_init(&dev->enc_mutex);
> mutex_init(&dev->dev_mutex);
> + mutex_init(&dev->dev_ctx_lock);
> spin_lock_init(&dev->irqlock);
>
> snprintf(dev->v4l2_dev.name, sizeof(dev->v4l2_dev.name), "%s",
> diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drvh
> index a042f607ed8d1..0bd85d0fb379a 100644
> --- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
> +++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
> @@ -178,6 +178,7 @@ struct mtk_vcodec_enc_ctx {
> *
> * @enc_mutex: encoder hardware lock.
> * @dev_mutex: video_device lock
> + * @dev_ctx_lock: the lock of context list
> * @encode_workqueue: encode work queue
> *
> * @enc_irq: h264 encoder irq resource
> @@ -205,6 +206,7 @@ struct mtk_vcodec_enc_dev {
> /* encoder hardware mutex lock */
> struct mutex enc_mutex;
> struct mutex dev_mutex;
> + struct mutex dev_ctx_lock;
> struct workqueue_struct *encode_workqueue;
>
> int enc_irq;
> diff --git a/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c b/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
> index 84ad1cc6ad171..51bb7ee141b9e 100644
> --- a/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
> +++ b/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
> @@ -47,12 +47,14 @@ static bool vpu_enc_check_ap_inst(struct mtk_vcodec_enc_dev *enc_dev, struct ven
> struct mtk_vcodec_enc_ctx *ctx;
> int ret = false;
>
> + mutex_lock(&enc_dev->dev_ctx_lock);
> list_for_each_entry(ctx, &enc_dev->ctx_list, list) {
> if (!IS_ERR_OR_NULL(ctx) && ctx->vpu_inst == vpu) {
> ret = true;
> break;
> }
> }
> + mutex_unlock(&enc_dev->dev_ctx_lock);
>
> return ret;
> }


2024-03-13 13:45:13

by Sebastian Fricke

[permalink] [raw]
Subject: Re: [PATCH v3,2/2] media: mediatek: vcodec: adding lock to protect encoder context list

Hey Yunfei,

On 22.02.2024 17:26, Yunfei Dong wrote:
>The ctx_list will be deleted when scp getting unexpected behavior, then the
>ctx_list->next will be NULL, the kernel driver maybe access NULL pointer in
>function vpu_enc_ipi_handler when going through each context, then reboot.
>
>Need to add lock to protect the ctx_list to make sure the ctx_list->next isn't
>NULL pointer.

Can we reword this slightly to make it grammatically correct?

My suggestion:
```
Add a lock for the ctx_list, to avoid accessing a NULL pointer within
the `vpu_enc_ipi_handler` function, when the ctx_list has been deleted
due to an unexpected behavior on the SCP IP block.
```

Greetings,
Sebastian

>
>Fixes: 1972e32431ed ("media: mediatek: vcodec: Fix possible invalid memory access for encoder")
>Signed-off-by: Yunfei Dong <[email protected]>
>---
> .../platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c | 4 ++--
> .../platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c | 5 +++++
> .../platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h | 2 ++
> drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c | 2 ++
> 4 files changed, 11 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c b/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
>index 9a11a2c248045..8d578b6902148 100644
>--- a/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
>+++ b/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
>@@ -73,12 +73,12 @@ static void mtk_vcodec_vpu_reset_enc_handler(void *priv)
>
> dev_err(&dev->plat_dev->dev, "Watchdog timeout!!");
>
>- mutex_lock(&dev->dev_mutex);
>+ mutex_lock(&dev->dev_ctx_lock);
> list_for_each_entry(ctx, &dev->ctx_list, list) {
> ctx->state = MTK_STATE_ABORT;
> mtk_v4l2_vdec_dbg(0, ctx, "[%d] Change to state MTK_STATE_ABORT", ctx->id);
> }
>- mutex_unlock(&dev->dev_mutex);
>+ mutex_unlock(&dev->dev_ctx_lock);
> }
>
> static const struct mtk_vcodec_fw_ops mtk_vcodec_vpu_msg = {
>diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
>index 5db2bf3db4c54..29524cd59ce8b 100644
>--- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
>+++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
>@@ -177,7 +177,9 @@ static int fops_vcodec_open(struct file *file)
> mtk_v4l2_venc_dbg(2, ctx, "Create instance [%d]@%p m2m_ctx=%p ",
> ctx->id, ctx, ctx->m2m_ctx);
>
>+ mutex_lock(&dev->dev_ctx_lock);
> list_add(&ctx->list, &dev->ctx_list);
>+ mutex_unlock(&dev->dev_ctx_lock);
>
> mutex_unlock(&dev->dev_mutex);
> mtk_v4l2_venc_dbg(0, ctx, "%s encoder [%d]", dev_name(&dev->plat_dev->dev),
>@@ -212,7 +214,9 @@ static int fops_vcodec_release(struct file *file)
> v4l2_fh_exit(&ctx->fh);
> v4l2_ctrl_handler_free(&ctx->ctrl_hdl);
>
>+ mutex_lock(&dev->dev_ctx_lock);
> list_del_init(&ctx->list);
>+ mutex_unlock(&dev->dev_ctx_lock);
> kfree(ctx);
> mutex_unlock(&dev->dev_mutex);
> return 0;
>@@ -294,6 +298,7 @@ static int mtk_vcodec_probe(struct platform_device *pdev)
>
> mutex_init(&dev->enc_mutex);
> mutex_init(&dev->dev_mutex);
>+ mutex_init(&dev->dev_ctx_lock);
> spin_lock_init(&dev->irqlock);
>
> snprintf(dev->v4l2_dev.name, sizeof(dev->v4l2_dev.name), "%s",
>diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
>index a042f607ed8d1..0bd85d0fb379a 100644
>--- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
>+++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.h
>@@ -178,6 +178,7 @@ struct mtk_vcodec_enc_ctx {
> *
> * @enc_mutex: encoder hardware lock.
> * @dev_mutex: video_device lock
>+ * @dev_ctx_lock: the lock of context list
> * @encode_workqueue: encode work queue
> *
> * @enc_irq: h264 encoder irq resource
>@@ -205,6 +206,7 @@ struct mtk_vcodec_enc_dev {
> /* encoder hardware mutex lock */
> struct mutex enc_mutex;
> struct mutex dev_mutex;
>+ struct mutex dev_ctx_lock;
> struct workqueue_struct *encode_workqueue;
>
> int enc_irq;
>diff --git a/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c b/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
>index 84ad1cc6ad171..51bb7ee141b9e 100644
>--- a/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
>+++ b/drivers/media/platform/mediatek/vcodec/encoder/venc_vpu_if.c
>@@ -47,12 +47,14 @@ static bool vpu_enc_check_ap_inst(struct mtk_vcodec_enc_dev *enc_dev, struct ven
> struct mtk_vcodec_enc_ctx *ctx;
> int ret = false;
>
>+ mutex_lock(&enc_dev->dev_ctx_lock);
> list_for_each_entry(ctx, &enc_dev->ctx_list, list) {
> if (!IS_ERR_OR_NULL(ctx) && ctx->vpu_inst == vpu) {
> ret = true;
> break;
> }
> }
>+ mutex_unlock(&enc_dev->dev_ctx_lock);
>
> return ret;
> }
>--
>2.18.0
>
>