media: mediatek: vcodec: adding lock to protect encoder context list

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.

Fixes: 1972e32431ed ("media: mediatek: vcodec: Fix possible invalid memory access for encoder")
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Sebastian Fricke <sebastian.fricke@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

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 62cafe25fed94421a15c27655b19d065a18a85b3..d7027d600208fc2f7233c5ca01ab7d590ef33042 100644 (file)
--- a/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
+++ b/drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c
@@ -65,12 +65,12 @@ 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 6319f24bc714b5eb3a7018f1e612afcf2dadf25e..3cb8a16222220e2d5480b48b48879112a68fc11f 100644 (file)
--- 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 a042f607ed8d1645a9dc3cf199b89e4280bc8337..0bd85d0fb379acbba3ac07c01e780cf57bef0305 100644 (file)
--- 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 84ad1cc6ad171ef2ea2767653d60e6d779e5604e..51bb7ee141b9e58ac98f940f5e419d9ef4df37ca 100644 (file)
--- 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;
 }