[media] coda: drop JPEG buffers not framed by SOI and EOI markers
authorPhilipp Zabel <p.zabel@pengutronix.de>
Wed, 8 Oct 2014 16:09:27 +0000 (13:09 -0300)
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>
Tue, 28 Oct 2014 17:41:07 +0000 (15:41 -0200)
This patch adds a quick check for valid JPEG frames before feeding them into
the bitstream buffer: Frames that do not begin with the JPEG start of image
marker and end with the end of image marker are dropped.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
drivers/media/platform/coda/coda-bit.c
drivers/media/platform/coda/coda-jpeg.c
drivers/media/platform/coda/coda.h

index 0c67cfd..b4029ae 100644 (file)
@@ -231,6 +231,16 @@ void coda_fill_bitstream(struct coda_ctx *ctx)
 
                src_buf = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
 
+               /* Drop frames that do not start/end with a SOI/EOI markers */
+               if (ctx->codec->src_fourcc == V4L2_PIX_FMT_JPEG &&
+                   !coda_jpeg_check_buffer(ctx, src_buf)) {
+                       v4l2_err(&ctx->dev->v4l2_dev,
+                                "dropping invalid JPEG frame\n");
+                       src_buf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
+                       v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_ERROR);
+                       continue;
+               }
+
                /* Buffer start position */
                start = ctx->bitstream_fifo.kfifo.in &
                        ctx->bitstream_fifo.kfifo.mask;
index 967b015..8fa3e35 100644 (file)
@@ -14,6 +14,9 @@
 
 #include "coda.h"
 
+#define SOI_MARKER     0xffd8
+#define EOI_MARKER     0xffd9
+
 /*
  * Typical Huffman tables for 8-bit precision luminance and
  * chrominance from JPEG ITU-T.81 (ISO/IEC 10918-1) Annex K.3
@@ -174,6 +177,16 @@ int coda_jpeg_write_tables(struct coda_ctx *ctx)
        return 0;
 }
 
+bool coda_jpeg_check_buffer(struct coda_ctx *ctx, struct vb2_buffer *vb)
+{
+       void *vaddr = vb2_plane_vaddr(vb, 0);
+       u16 soi = be16_to_cpup((__be16 *)vaddr);
+       u16 eoi = be16_to_cpup((__be16 *)(vaddr +
+                                         vb2_get_plane_payload(vb, 0) - 2));
+
+       return soi == SOI_MARKER && eoi == EOI_MARKER;
+}
+
 /*
  * Scale quantization table using nonlinear scaling factor
  * u8 qtab[64], scale [50,190]
index 8dd81a7..5dd47e5 100644 (file)
@@ -293,6 +293,7 @@ void coda_bit_stream_end_flag(struct coda_ctx *ctx);
 
 int coda_h264_padding(int size, char *p);
 
+bool coda_jpeg_check_buffer(struct coda_ctx *ctx, struct vb2_buffer *vb);
 int coda_jpeg_write_tables(struct coda_ctx *ctx);
 void coda_set_jpeg_compression_quality(struct coda_ctx *ctx, int quality);