[PATCH] ALSA: usb-audio: Fix memleak in scarlett2_add_new_ctl

[Dinghao Liu]

When snd_usb_mixer_add_control() fails, elem needs to be
freed just like when snd_ctl_new1() fails. However, current
code is returning directly and ends up leaking memory.

Fixes: 9e4d5c1be21f0 ("ALSA: usb-audio: Scarlett Gen 2 mixer interface")
Signed-off-by: Dinghao Liu <dinghao....@zju.edu.cn>
---
 sound/usb/mixer_scarlett_gen2.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/sound/usb/mixer_scarlett_gen2.c b/sound/usb/mixer_scarlett_gen2.c
index 74c00c905d24..4b2da0866cdc 100644
--- a/sound/usb/mixer_scarlett_gen2.c
+++ b/sound/usb/mixer_scarlett_gen2.c
@@ -964,8 +964,10 @@ static int scarlett2_add_new_ctl(struct 
usb_mixer_interface *mixer,
        strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
 
        err = snd_usb_mixer_add_control(&elem->head, kctl);
-       if (err < 0)
+       if (err < 0) {
+               kfree(elem);
                return err;
+       }
 
        if (kctl_return)
                *kctl_return = kctl;
-- 
2.17.1