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 <yunfei.dong@xxxxxxxxxxxx>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx>
> ---
> .../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;
> }
