[alsa-devel] [PATCH] 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 --- sound/usb/mixer.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 73d7dff..53dccbf 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -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;
On Sat, 27 Apr 2019 08:06:46 +0200, Wenwen Wang wrote:
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
Applied now, thanks.
Takashi
participants (2)
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Takashi Iwai
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Wenwen Wang