Unverified Commit 6f0307df authored Jul 07, 2020 by Pierre-Louis Bossart Committed by Mark Brown Jul 08, 2020

ASoC: topology: fix kernel oops on route addition error



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: 7df04ea7 ('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.intel.com


Signed-off-by: Mark Brown <broonie@kernel.org>

parent 503ed522

sound/soc/soc-topology.c

+17 −5

Original line number	Diff line number	Diff line
		@@ -1261,17 +1261,29 @@ static int soc_tplg_dapm_graph_elems_load(struct soc_tplg *tplg,
		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.