[PATCH 1/1] ALSA: opl3: fix infoleak in opl3

From: Xidong Wang
Date: Sun Jul 05 2020 - 23:29:00 EST


From: xidongwang <wangxidong_97@xxxxxxx>

The stack object âinfoâ in snd_opl3_ioctl() has a leaking problem.
It has 2 padding bytes which are not initialized and leaked via
âcopy_to_userâ.

Signed-off-by: xidongwang <wangxidong_97@xxxxxxx>
---
sound/drivers/opl3/opl3_synth.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/sound/drivers/opl3/opl3_synth.c b/sound/drivers/opl3/opl3_synth.c
index e69a4ef..08c10ac 100644
--- a/sound/drivers/opl3/opl3_synth.c
+++ b/sound/drivers/opl3/opl3_synth.c
@@ -91,6 +91,8 @@ int snd_opl3_ioctl(struct snd_hwdep * hw, struct file *file,
{
struct snd_dm_fm_info info;

+ memset(&info, 0, sizeof(info));
+
info.fm_mode = opl3->fm_mode;
info.rhythm = opl3->rhythm;
if (copy_to_user(argp, &info, sizeof(struct snd_dm_fm_info)))
--
2.7.4