From ec5a97624a8de4f44b090cf53bd48c05458e0b17 Mon Sep 17 00:00:00 2001
From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Date: Mon, 21 Sep 2020 14:08:11 +0300
Subject: [PATCH] ASoC: SOF: control: fix size checks for volatile ext_bytes control .get()
References: jsc#SLE-16518
Patch-mainline: v5.10-rc1
Git-commit: ec5a97624a8de4f44b090cf53bd48c05458e0b17
Mirror addition of checks for regular ext_bytes controls.
Fixes: 783560d02dd61 ('ASoC: SOF: Implement snd_sof_bytes_ext_volatile_get kcontrol IO')
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20200921110814.2910477-3-kai.vehmanen@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
sound/soc/sof/control.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/sound/soc/sof/control.c b/sound/soc/sof/control.c
index 8d499d0e331d..9465611156d5 100644
--- a/sound/soc/sof/control.c
+++ b/sound/soc/sof/control.c
@@ -369,6 +369,14 @@ int snd_sof_bytes_ext_volatile_get(struct snd_kcontrol *kcontrol, unsigned int _
int ret;
int err;
+ /*
+ * Decrement the limit by ext bytes header size to
+ * ensure the user space buffer is not exceeded.
+ */
+ if (size < sizeof(struct snd_ctl_tlv))
+ return -ENOSPC;
+ size -= sizeof(struct snd_ctl_tlv);
+
ret = pm_runtime_get_sync(scomp->dev);
if (ret < 0 && ret != -EACCES) {
dev_err_ratelimited(scomp->dev, "error: bytes_ext get failed to resume %d\n", ret);
@@ -396,6 +404,12 @@ int snd_sof_bytes_ext_volatile_get(struct snd_kcontrol *kcontrol, unsigned int _
data_size = cdata->data->size + sizeof(const struct sof_abi_hdr);
+ /* make sure we don't exceed size provided by user space for data */
+ if (data_size > size) {
+ ret = -ENOSPC;
+ goto out;
+ }
+
header.numid = scontrol->cmd;
header.length = data_size;
if (copy_to_user(tlvd, &header, sizeof(const struct snd_ctl_tlv))) {
--
2.16.4