ASoC: Intel: Common: Fix NULL dereference in tx_wait_done

rx_data and rx_bytes present for tx_wait_done are optional parameters.
If not provided, function should not attempt to copy received data.
This change fixes memcpy NULL pointer dereference issue occurring when
optional rx_data is NULL while received message size is non-zero.

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/intel/common/sst-ipc.c b/sound/soc/intel/common/sst-ipc.c
index dcff138..fc3340f 100644 (file)
--- a/sound/soc/intel/common/sst-ipc.c
+++ b/sound/soc/intel/common/sst-ipc.c
@@ -71,7 +71,7 @@ static int tx_wait_done(struct sst_generic_ipc *ipc,
        } else {
 
                /* copy the data returned from DSP */
-               if (msg->rx_size)
+               if (rx_data)
                        memcpy(rx_data, msg->rx_data, msg->rx_size);
                ret = msg->errno;
        }