From 6d5574ed5c8b1a1f31fcbdab5d26e15533c442ca Mon Sep 17 00:00:00 2001
From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Thu, 14 Sep 2017 22:44:12 +0200
Subject: [PATCH] ASoC: topology: Fix a potential NULL pointer dereference in 'soc_tplg_dapm_widget_denum_create()'
Git-commit: 6d5574ed5c8b1a1f31fcbdab5d26e15533c442ca
Patch-mainline: v4.14-rc8
References: bsc#1051510

if 'se = kzalloc()' fails in the 'for' loop, we will branch to 'err'.
But in this case, 'kc[i].private_value' will still be NULL. A NULL pointer
dereference will then occur is the error handling path.

In such a case, it is safe to just 'continue' in order to skip this entry
and free the other ones.

Fixes: 1a7dd6e2f192 ("ASoC: topology: Allow a widget to have multiple enum controls")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 sound/soc/soc-topology.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/sound/soc/soc-topology.c
+++ b/sound/soc/soc-topology.c
@@ -1358,6 +1358,9 @@ err_se:
 	for (; i >= 0; i--) {
 		/* free values and texts */
 		se = (struct soc_enum *)kc[i].private_value;
+		if (!se)
+			continue;
+
 		kfree(se->dobj.control.dvalues);
 		for (j = 0; j < ec->items; j++)
 			kfree(se->dobj.control.dtexts[j]);