media: Avoid parsing quantization and huffman tables

These are optional in struct v4l2_jpeg_header, so skip DHT/DQT segment
parsing if huffman_tables/quantization_tables were not requested by user,
to save time.
However, do count them (num_dht/num_dqt).

Signed-off-by: Mirela Rabulea <mirela.rabulea@nxp.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/v4l2-core/v4l2-jpeg.c b/drivers/media/v4l2-core/v4l2-jpeg.c
index c4c0d6dd4577986a58caa80480f2781baa63c5d3..c2513b775f6a7f14cea704f7a8b17d81208b6692 100644 (file)
--- a/drivers/media/v4l2-core/v4l2-jpeg.c
+++ b/drivers/media/v4l2-core/v4l2-jpeg.c
@@ -537,6 +537,10 @@ int v4l2_jpeg_parse_header(void *buf, size_t len, struct v4l2_jpeg_header *out)
                                        &out->dht[out->num_dht++ % 4]);
                        if (ret < 0)
                                return ret;
+                       if (!out->huffman_tables) {
+                               ret = jpeg_skip_segment(&stream);
+                               break;
+                       }
                        ret = jpeg_parse_huffman_tables(&stream,
                                                        out->huffman_tables);
                        break;
@@ -545,6 +549,10 @@ int v4l2_jpeg_parse_header(void *buf, size_t len, struct v4l2_jpeg_header *out)
                                        &out->dqt[out->num_dqt++ % 4]);
                        if (ret < 0)
                                return ret;
+                       if (!out->quantization_tables) {
+                               ret = jpeg_skip_segment(&stream);
+                               break;
+                       }
                        ret = jpeg_parse_quantization_tables(&stream,
                                        out->frame.precision,
                                        out->quantization_tables);