[PATCH 3/3] media: mediatek: vcodec: fix h264 stateless decoder smatch warning

From: Yunfei Dong
Date: Thu Feb 29 2024 - 04:56:37 EST


Fix smatch static checker warning for vdec_h264_req_if.c. Leading
to kernel crash when fb is NULL.

Fixes: 06fa5f757dc5 ("media: mtk-vcodec: vdec: support stateless H.264 decoding")
Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx>
---
.../mediatek/vcodec/decoder/vdec/vdec_h264_req_if.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_h264_req_if.c b/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_h264_req_if.c
index 5600f1df653d..f1c164b644f8 100644
--- a/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_h264_req_if.c
+++ b/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_h264_req_if.c
@@ -347,11 +347,16 @@ static int vdec_h264_slice_decode(void *h_vdec, struct mtk_vcodec_mem *bs,
return vpu_dec_reset(vpu);

fb = inst->ctx->dev->vdec_pdata->get_cap_buffer(inst->ctx);
+ if (!fb) {
+ mtk_vdec_err(inst->ctx, "fb buffer is NULL");
+ return -EBUSY;
+ }
+
src_buf_info = container_of(bs, struct mtk_video_dec_buf, bs_buffer);
dst_buf_info = container_of(fb, struct mtk_video_dec_buf, frame_buffer);

- y_fb_dma = fb ? (u64)fb->base_y.dma_addr : 0;
- c_fb_dma = fb ? (u64)fb->base_c.dma_addr : 0;
+ y_fb_dma = (u64)fb->base_y.dma_addr;
+ c_fb_dma = (u64)fb->base_c.dma_addr;

mtk_vdec_debug(inst->ctx, "+ [%d] FB y_dma=%llx c_dma=%llx va=%p",
inst->num_nalu, y_fb_dma, c_fb_dma, fb);
--
2.25.1