Re: [PATCH] ASoC: topology: Perform component check upfront

On Thu, Mar 12, 2020 at 3:14 AM Amadeusz Sławiński < amadeuszx.slawinski@linux.intel.com> wrote:

Function soc_tplg_dbytes_create(), calls soc_tplg_init_kcontrol() to perform additional driver specific initialization. While soc_tplg_init_kcontrol() ensures that component is valid before invoking ops->control_load, there is no such check at the end of soc_tplg_dbytes_create() where list_add() is used.

Also in quite a few places, there is reference of tplg->comp->dapm or tplg->comp->card, without any checks for tplg->comp.

In consequence of the above this may lead to referencing NULL pointer.

This allows for removal of now unnecessary checks.

Signed-off-by: Amadeusz Sławiński amadeuszx.slawinski@linux.intel.com

sound/soc/soc-topology.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/sound/soc/soc-topology.c b/sound/soc/soc-topology.c index 575da6aba807..66958c57d884 100644 --- a/sound/soc/soc-topology.c +++ b/sound/soc/soc-topology.c @@ -251,7 +251,7 @@ static int soc_tplg_vendor_load_(struct soc_tplg *tplg, { int ret = 0;

•   if (tplg->comp && tplg->ops && tplg->ops->vendor_load)
  

•   if (tplg->ops && tplg->ops->vendor_load)
            ret = tplg->ops->vendor_load(tplg->comp, tplg->index, hdr);
    else {
            dev_err(tplg->dev, "ASoC: no vendor load callback for ID
  

%d\n", @@ -283,7 +283,7 @@ static int soc_tplg_vendor_load(struct soc_tplg *tplg, static int soc_tplg_widget_load(struct soc_tplg *tplg, struct snd_soc_dapm_widget *w, struct snd_soc_tplg_dapm_widget *tplg_w) {

•   if (tplg->comp && tplg->ops && tplg->ops->widget_load)
  

•   if (tplg->ops && tplg->ops->widget_load)
            return tplg->ops->widget_load(tplg->comp, tplg->index, w,
                    tplg_w);
  
  

@@ -295,7 +295,7 @@ static int soc_tplg_widget_load(struct soc_tplg *tplg, static int soc_tplg_widget_ready(struct soc_tplg *tplg, struct snd_soc_dapm_widget *w, struct snd_soc_tplg_dapm_widget *tplg_w) {

•   if (tplg->comp && tplg->ops && tplg->ops->widget_ready)
  

•   if (tplg->ops && tplg->ops->widget_ready)
            return tplg->ops->widget_ready(tplg->comp, tplg->index, w,
                    tplg_w);
  
  

@@ -307,7 +307,7 @@ static int soc_tplg_dai_load(struct soc_tplg *tplg, struct snd_soc_dai_driver *dai_drv, struct snd_soc_tplg_pcm *pcm, struct snd_soc_dai *dai) {

•   if (tplg->comp && tplg->ops && tplg->ops->dai_load)
  

•   if (tplg->ops && tplg->ops->dai_load)
            return tplg->ops->dai_load(tplg->comp, tplg->index,
  

dai_drv, pcm, dai);

@@ -318,7 +318,7 @@ static int soc_tplg_dai_load(struct soc_tplg *tplg, static int soc_tplg_dai_link_load(struct soc_tplg *tplg, struct snd_soc_dai_link *link, struct snd_soc_tplg_link_config *cfg) {

•   if (tplg->comp && tplg->ops && tplg->ops->link_load)
  

•   if (tplg->ops && tplg->ops->link_load)
            return tplg->ops->link_load(tplg->comp, tplg->index, link,
  

cfg);

    return 0;

@@ -327,7 +327,7 @@ static int soc_tplg_dai_link_load(struct soc_tplg *tplg, /* tell the component driver that all firmware has been loaded in this request */ static void soc_tplg_complete(struct soc_tplg *tplg) {

•   if (tplg->comp && tplg->ops && tplg->ops->complete)
  

•   if (tplg->ops && tplg->ops->complete)
            tplg->ops->complete(tplg->comp);
  

}

@@ -684,7 +684,7 @@ EXPORT_SYMBOL_GPL(snd_soc_tplg_widget_bind_event); static int soc_tplg_init_kcontrol(struct soc_tplg *tplg, struct snd_kcontrol_new *k, struct snd_soc_tplg_ctl_hdr *hdr) {

•   if (tplg->comp && tplg->ops && tplg->ops->control_load)
  

•   if (tplg->ops && tplg->ops->control_load)
            return tplg->ops->control_load(tplg->comp, tplg->index, k,
                    hdr);
  
  

@@ -1174,7 +1174,7 @@ static int soc_tplg_kcontrol_elems_load(struct soc_tplg *tplg, static int soc_tplg_add_route(struct soc_tplg *tplg, struct snd_soc_dapm_route *route) {

•   if (tplg->comp && tplg->ops && tplg->ops->dapm_route_load)
  

•   if (tplg->ops && tplg->ops->dapm_route_load)
            return tplg->ops->dapm_route_load(tplg->comp, tplg->index,
                    route);
  
  

@@ -2564,7 +2564,7 @@ static int soc_tplg_manifest_load(struct soc_tplg *tplg, }

    /* pass control to component driver for optional further init */

•   if (tplg->comp && tplg->ops && tplg->ops->manifest)
  

•   if (tplg->ops && tplg->ops->manifest)
            ret = tplg->ops->manifest(tplg->comp, tplg->index,
  

_manifest);

    if (!abi_match) /* free the duplicated one */

@@ -2736,6 +2736,10 @@ int snd_soc_tplg_component_load(struct snd_soc_component *comp, struct soc_tplg tplg; int ret;

•   /* component needs to exist to keep and reference data while
  

parsing */

•   if (!comp)
  

•           return -EINVAL;
  

Amadeusz,

Thanks for this change. I agree that the checks for tplg->comp in the above functions should be removed but is the check here really necessary at all? snd_soc_tplg_component_load() is typically called when a component is probed. Can it ever be null at all if it is getting probed?

Thanks, Ranjani