[PATCH v2] ALSA: pcm: fix multiple memory leak bugs

From: Wenwen Wang
Date: Wed Aug 07 2019 - 03:10:40 EST


In hiface_pcm_init(), 'rt' is firstly allocated through kzalloc(). Later
on, hiface_pcm_init_urb() is invoked to initialize 'rt->out_urbs[i]'. In
hiface_pcm_init_urb(), 'rt->out_urbs[i].buffer' is allocated through
kzalloc(). However, if hiface_pcm_init_urb() fails, both 'rt' and
'rt->out_urbs[i].buffer' are not deallocated, leading to memory leak bugs.
Also, 'rt->out_urbs[i].buffer' is not deallocated if snd_pcm_new() fails.

To fix the above issues, free 'rt' and 'rt->out_urbs[i].buffer'.

Signed-off-by: Wenwen Wang <wenwen@xxxxxxxxxx>
---
sound/usb/hiface/pcm.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/sound/usb/hiface/pcm.c b/sound/usb/hiface/pcm.c
index 14fc1e1..9b132aa 100644
--- a/sound/usb/hiface/pcm.c
+++ b/sound/usb/hiface/pcm.c
@@ -599,12 +599,18 @@ int hiface_pcm_init(struct hiface_chip *chip, u8
extra_freq)
for (i = 0; i < PCM_N_URBS; i++) {
ret = hiface_pcm_init_urb(&rt->out_urbs[i], chip, OUT_EP,
hiface_pcm_out_urb_handler);
- if (ret < 0)
+ if (ret < 0) {
+ for (; i >= 0; i--)
+ kfree(rt->out_urbs[i].buffer);
+ kfree(rt);
return ret;
+ }
}

ret = snd_pcm_new(chip->card, "USB-SPDIF Audio", 0, 1, 0, &pcm);
if (ret < 0) {
+ for (i = 0; i < PCM_N_URBS; i++)
+ kfree(rt->out_urbs[i].buffer);
kfree(rt);
dev_err(&chip->dev->dev, "Cannot create pcm instance\n");
return ret;
--
2.7.4