[PATCH] ASoC: dapm: fix a memory leak bug

From: Wenwen Wang <wang6495@umn.edu>
To: Wenwen Wang <wenwen@cs.uga.edu>
Cc: Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>, Jaroslav Kysela <perex@perex.cz>,
	Takashi Iwai <tiwai@suse.com>,
	alsa-devel@alsa-project.org (moderated list:SOUND - SOC LAYER /
	DYNAMIC AUDIO POWER MANAGEM...),
	linux-kernel@vger.kernel.org (open list)
Subject: [PATCH] ASoC: dapm: fix a memory leak bug
Date: Mon, 22 Jul 2019 08:57:44 -0500	[thread overview]
Message-ID: <1563803864-2809-1-git-send-email-wang6495@umn.edu> (raw)

From: Wenwen Wang <wenwen@cs.uga.edu>

In snd_soc_dapm_new_control_unlocked(), a kernel buffer is allocated in
dapm_cnew_widget() to hold the new dapm widget. Then, different actions are
taken according to the id of the widget, i.e., 'w->id'. If any failure
occurs during this process, snd_soc_dapm_new_control_unlocked() should be
terminated by going to the 'request_failed' label. However, the allocated
kernel buffer is not freed on this code path, leading to a memory leak bug.

To fix the above issue, free the buffer before returning from
snd_soc_dapm_new_control_unlocked() through the 'request_failed' label.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
---
 sound/soc/soc-dapm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index f013b24..23b9b25 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -3706,6 +3706,8 @@ snd_soc_dapm_new_control_unlocked(struct snd_soc_dapm_context *dapm,
 		dev_err(dapm->dev, "ASoC: Failed to request %s: %d\n",
 			w->name, ret);
 
+	kfree_const(w->sname);
+	kfree(w);
 	return ERR_PTR(ret);
 }
 
-- 
2.7.4

