Commit cb517359 authored Apr 27, 2019 by Wenwen Wang Committed by Takashi Iwai Apr 28, 2019

ALSA: usb-audio: Fix a memory leak bug



In parse_audio_selector_unit(), the string array 'namelist' is allocated
through kmalloc_array(), and each string pointer in this array, i.e.,
'namelist[]', is allocated through kmalloc() in the following for loop.
Then, a control instance 'kctl' is created by invoking snd_ctl_new1(). If
an error occurs during the creation process, the string array 'namelist',
including all string pointers in the array 'namelist[]', should be freed,
before the error code ENOMEM is returned. However, the current code does
not free 'namelist[]', resulting in memory leaks.

To fix the above issue, free all string pointers 'namelist[]' in a loop.

Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

parent 4ab1ae34

sound/usb/mixer.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -2675,6 +2675,8 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
		kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
		if (! kctl) {
		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
		for (i = 0; i < desc->bNrInPins; i++)
		kfree(namelist[i]);
		kfree(namelist);
		kfree(cval);
		return -ENOMEM;

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