ASoC: Intel: check and clear runtime module pointer

Add check runtime module pointers before freeing them, and clear
them to NULL after freed.

With this implemented, we can avoid NULL pointer dereference or
double free errors.

Signed-off-by: Jie Yang <yang.jie@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/intel/haswell/sst-haswell-pcm.c b/sound/soc/intel/haswell/sst-haswell-pcm.c
index 23ae0400d6db99668b3d2b48b47eb003d2fc2e46..f97fa5ab93d3676112bbf871a4ae85c9a01797ca 100644 (file)
--- a/sound/soc/intel/haswell/sst-haswell-pcm.c
+++ b/sound/soc/intel/haswell/sst-haswell-pcm.c
@@ -928,10 +928,15 @@ static void hsw_pcm_free_modules(struct hsw_priv_data *pdata)
 
        for (i = 0; i < ARRAY_SIZE(mod_map); i++) {
                pcm_data = &pdata->pcm[mod_map[i].dai_id][mod_map[i].stream];
-               sst_hsw_runtime_module_free(pcm_data->runtime);
+               if (pcm_data->runtime){
+                       sst_hsw_runtime_module_free(pcm_data->runtime);
+                       pcm_data->runtime = NULL;
+               }
        }
-       if (sst_hsw_is_module_loaded(hsw, SST_HSW_MODULE_WAVES)) {
+       if (sst_hsw_is_module_loaded(hsw, SST_HSW_MODULE_WAVES) &&
+                               pdata->runtime_waves) {
                sst_hsw_runtime_module_free(pdata->runtime_waves);
+               pdata->runtime_waves = NULL;
        }
 }