media: vicodec: set state resolution from raw format

hverkuil · mchehab · commit daa3fc4454b2 · 2018-12-03T15:04:36.000-05:00
The state structure contains the resolution expected by the decoder
and encoder. For an encoder that resolution should be taken from the
OUTPUT format, and for a decoder from the CAPTURE format.

If the wrong format is picked, a buffer overrun can occur if there is
a mismatch between the CAPTURE and OUTPUT formats.

The real fix would be to correctly implement the stateful codec
specification, but that will take more time. For now just prevent the
buffer overrun.

Signed-off-by: Hans Verkuil &lt;hverkuil-cisco@xs4all.nl&gt;
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab+samsung@kernel.org&gt;
diff --git a/drivers/media/platform/vicodec/vicodec-core.c b/drivers/media/platform/vicodec/vicodec-core.c
@@ -997,11 +997,18 @@ static int vicodec_start_streaming(struct vb2_queue *q,
 
 	q_data->sequence = 0;
 
-	if (!V4L2_TYPE_IS_OUTPUT(q->type))
+	if (!V4L2_TYPE_IS_OUTPUT(q->type)) {
+		if (!ctx->is_enc) {
+			state->width = q_data->width;
+			state->height = q_data->height;
+		}
 		return 0;
+	}
 
-	state->width = q_data->width;
-	state->height = q_data->height;
+	if (ctx->is_enc) {
+		state->width = q_data->width;
+		state->height = q_data->height;
+	}
 	state->ref_frame.width = state->ref_frame.height = 0;
 	state->ref_frame.luma = kvmalloc(size + 2 * size / chroma_div,
 					 GFP_KERNEL);
