[media] coda: move meta out of padding

Handle an empty buffer metadata list without crashing. This can happen
if the decoder is fed a broken stream, or multiple compressed frames in
a single queued buffer.

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>

diff --git a/drivers/media/platform/coda/coda-bit.c b/drivers/media/platform/coda/coda-bit.c
index b4029ae293d36761a3542fedbdbad48bfdbb26d7..f6cf337bf377f1aabea4f5896efd4140ec79c971 100644 (file)
--- a/drivers/media/platform/coda/coda-bit.c
+++ b/drivers/media/platform/coda/coda-bit.c
@@ -1565,6 +1565,7 @@ static int coda_prepare_decode(struct coda_ctx *ctx)
        struct vb2_buffer *dst_buf;
        struct coda_dev *dev = ctx->dev;
        struct coda_q_data *q_data_dst;
+       struct coda_buffer_meta *meta;
        u32 reg_addr, reg_stride;
 
        dst_buf = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
@@ -1643,12 +1644,12 @@ static int coda_prepare_decode(struct coda_ctx *ctx)
                coda_write(dev, ctx->iram_info.axi_sram_use,
                                CODA7_REG_BIT_AXI_SRAM_USE);
 
-       if (ctx->codec->src_fourcc == V4L2_PIX_FMT_JPEG) {
-               struct coda_buffer_meta *meta;
+       meta = list_first_entry_or_null(&ctx->buffer_meta_list,
+                                       struct coda_buffer_meta, list);
+
+       if (meta && ctx->codec->src_fourcc == V4L2_PIX_FMT_JPEG) {
 
                /* If this is the last buffer in the bitstream, add padding */
-               meta = list_first_entry(&ctx->buffer_meta_list,
-                                     struct coda_buffer_meta, list);
                if (meta->end == (ctx->bitstream_fifo.kfifo.in &
                                  ctx->bitstream_fifo.kfifo.mask)) {
                        static unsigned char buf[512];