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

Wenwen Wang wenwen at cs.uga.edu
Wed Aug 7 09:09:59 CEST 2019


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 at cs.uga.edu>
---
 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


More information about the Alsa-devel mailing list