From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
commit 6f0307df83f2aa6bdf656c2219c89ce96502d20e upstream.
When errors happens while loading graph components, the kernel oopses while trying to remove all topology components. This can be root-caused to a list pointing to memory that was already freed on error.
remove_route() is already called on errors and will perform the required cleanups so there's no need to free the route memory in soc_tplg_dapm_graph_elems_load() if the route was added to the list. We do however want to free the routes allocated but not added to the list.
Fixes: 7df04ea7a31ea ('ASoC: topology: modify dapm route loading routine and add dapm route unloading') Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Reviewed-by: Kai Vehmanen kai.vehmanen@linux.intel.com Link: https://lore.kernel.org/r/20200707203749.113883-2-pierre-louis.bossart@linux... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- sound/soc/soc-topology.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-)
--- a/sound/soc/soc-topology.c +++ b/sound/soc/soc-topology.c @@ -1284,17 +1284,29 @@ static int soc_tplg_dapm_graph_elems_loa list_add(&routes[i]->dobj.list, &tplg->comp->dobj_list);
ret = soc_tplg_add_route(tplg, routes[i]); - if (ret < 0) + if (ret < 0) { + /* + * this route was added to the list, it will + * be freed in remove_route() so increment the + * counter to skip it in the error handling + * below. + */ + i++; break; + }
/* add route, but keep going if some fail */ snd_soc_dapm_add_routes(dapm, routes[i], 1); }
- /* free memory allocated for all dapm routes in case of error */ - if (ret < 0) - for (i = 0; i < count ; i++) - kfree(routes[i]); + /* + * free memory allocated for all dapm routes not added to the + * list in case of error + */ + if (ret < 0) { + while (i < count) + kfree(routes[i++]); + }
/* * free pointer to array of dapm routes as this is no longer needed.