[alsa-devel] [PATCH] ASoC: topology: fix soc_tplg_fe_link_create() - link->dobj initialization order

[Jaroslav Kysela]

The code which checks the return value for snd_soc_add_dai_link() call
in soc_tplg_fe_link_create() moved the snd_soc_add_dai_link() call before
link->dobj members initialization.

While it does not affect the latest kernels, the old soc-core.c code
in the stable kernels is affected. The snd_soc_add_dai_link() function uses
the link->dobj.type member to check, if the link structure is valid.

Reorder the link->dobj initialization to make things work again.
It's harmless for the recent code (and the structure should be properly
initialized before other calls anyway).

The problem is in stable linux-5.4.y since version 5.4.11 when the
upstream commit 76d270364932 was applied.

Fixes: 76d270364932 ("ASoC: topology: Check return value for snd_soc_add_dai_link()")
Cc: Dragos Tarcatu <dragos_tarcatu at mentor.com>
Cc: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
Cc: Ranjani Sridharan <ranjani.sridharan at linux.intel.com>
Cc: Mark Brown <broonie at kernel.org>
Cc: <stable at vger.kernel.org>
Signed-off-by: Jaroslav Kysela <perex at perex.cz>
---
 sound/soc/soc-topology.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/sound/soc/soc-topology.c b/sound/soc/soc-topology.c
index 92e4f4d08bfa..4e1fe623c390 100644
--- a/sound/soc/soc-topology.c
+++ b/sound/soc/soc-topology.c
@@ -1906,6 +1906,10 @@ static int soc_tplg_fe_link_create(struct soc_tplg *tplg,
 	link->num_codecs = 1;
 	link->num_platforms = 1;
 
+	link->dobj.index = tplg->index;
+	link->dobj.ops = tplg->ops;
+	link->dobj.type = SND_SOC_DOBJ_DAI_LINK;
+
 	if (strlen(pcm->pcm_name)) {
 		link->name = kstrdup(pcm->pcm_name, GFP_KERNEL);
 		link->stream_name = kstrdup(pcm->pcm_name, GFP_KERNEL);
@@ -1942,9 +1946,6 @@ static int soc_tplg_fe_link_create(struct soc_tplg *tplg,
 		goto err;
 	}
 
-	link->dobj.index = tplg->index;
-	link->dobj.ops = tplg->ops;
-	link->dobj.type = SND_SOC_DOBJ_DAI_LINK;
 	list_add(&link->dobj.list, &tplg->comp->dobj_list);
 
 	return 0;
-- 
2.24.1