[PATCH 3.16 228/328] ALSA: emu10k1: fix possible info leak to userspace on SNDRV_EMU10K1_IOCTL_INFO

[Ben Hutchings]

3.16.62-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Willy Tarreau <w...@1wt.eu>

commit 49434c6c575d2008c0abbc93e615019f39e01252 upstream.

snd_emu10k1_fx8010_ioctl(SNDRV_EMU10K1_IOCTL_INFO) allocates
memory using kmalloc() and partially fills it by calling
snd_emu10k1_fx8010_info() before returning the resulting
structure to userspace, leaving uninitialized holes. Let's
just use kzalloc() here.

BugLink: http://blog.infosectcbr.com.au/2018/09/linux-kernel-infoleaks.html
Signed-off-by: Willy Tarreau <w...@1wt.eu>
Cc: Jann Horn <ja...@google.com>
Signed-off-by: Takashi Iwai <ti...@suse.de>
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
 sound/pci/emu10k1/emufx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/sound/pci/emu10k1/emufx.c
+++ b/sound/pci/emu10k1/emufx.c
@@ -2521,7 +2521,7 @@ static int snd_emu10k1_fx8010_ioctl(stru
                emu->support_tlv = 1;
                return put_user(SNDRV_EMU10K1_VERSION, (int __user *)argp);
        case SNDRV_EMU10K1_IOCTL_INFO:
-               info = kmalloc(sizeof(*info), GFP_KERNEL);
+               info = kzalloc(sizeof(*info), GFP_KERNEL);
                if (!info)
                        return -ENOMEM;
                snd_emu10k1_fx8010_info(emu, info);