linux/sound/soc/qcom/common.c
Dan Carpenter 4e59dd249c
ASoC: qcom: common: Fix refcounting in qcom_snd_parse_of()
There are two issues in this function.

1) We can't drop the refrences on "cpu", "codec" and "platform" before
   we take the reference.  This doesn't cause a problem on the first
   iteration because those pointers start as NULL so the of_node_put()
   is a no-op.  But on the subsequent iterations, it will lead to a use
   after free.

2) If the devm_kzalloc() allocation failed then the code returned
   directly instead of cleaning up.

Fixes: c1e6414cdc ("ASoC: qcom: common: Fix refcount imbalance on error")
Fixes: 1e36ea360a ("ASoC: qcom: common: use modern dai_link style")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20201105125154.GA176426@mwanda
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-10 17:28:25 +00:00

173 lines
4.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018, Linaro Limited.
// Copyright (c) 2018, The Linux Foundation. All rights reserved.
#include <linux/module.h>
#include "common.h"
int qcom_snd_parse_of(struct snd_soc_card *card)
{
struct device_node *np;
struct device_node *codec = NULL;
struct device_node *platform = NULL;
struct device_node *cpu = NULL;
struct device *dev = card->dev;
struct snd_soc_dai_link *link;
struct of_phandle_args args;
struct snd_soc_dai_link_component *dlc;
int ret, num_links;
ret = snd_soc_of_parse_card_name(card, "model");
if (ret == 0 && !card->name)
/* Deprecated, only for compatibility with old device trees */
ret = snd_soc_of_parse_card_name(card, "qcom,model");
if (ret) {
dev_err(dev, "Error parsing card name: %d\n", ret);
return ret;
}
/* DAPM routes */
if (of_property_read_bool(dev->of_node, "audio-routing")) {
ret = snd_soc_of_parse_audio_routing(card, "audio-routing");
if (ret)
return ret;
}
/* Deprecated, only for compatibility with old device trees */
if (of_property_read_bool(dev->of_node, "qcom,audio-routing")) {
ret = snd_soc_of_parse_audio_routing(card, "qcom,audio-routing");
if (ret)
return ret;
}
ret = snd_soc_of_parse_aux_devs(card, "aux-devs");
if (ret)
return ret;
/* Populate links */
num_links = of_get_child_count(dev->of_node);
/* Allocate the DAI link array */
card->dai_link = devm_kcalloc(dev, num_links, sizeof(*link), GFP_KERNEL);
if (!card->dai_link)
return -ENOMEM;
card->num_links = num_links;
link = card->dai_link;
for_each_child_of_node(dev->of_node, np) {
dlc = devm_kzalloc(dev, 2 * sizeof(*dlc), GFP_KERNEL);
if (!dlc) {
ret = -ENOMEM;
goto err_put_np;
}
link->cpus = &dlc[0];
link->platforms = &dlc[1];
link->num_cpus = 1;
link->num_platforms = 1;
ret = of_property_read_string(np, "link-name", &link->name);
if (ret) {
dev_err(card->dev, "error getting codec dai_link name\n");
goto err_put_np;
}
cpu = of_get_child_by_name(np, "cpu");
platform = of_get_child_by_name(np, "platform");
codec = of_get_child_by_name(np, "codec");
if (!cpu) {
dev_err(dev, "%s: Can't find cpu DT node\n", link->name);
ret = -EINVAL;
goto err;
}
ret = of_parse_phandle_with_args(cpu, "sound-dai",
"#sound-dai-cells", 0, &args);
if (ret) {
dev_err(card->dev, "%s: error getting cpu phandle\n", link->name);
goto err;
}
link->cpus->of_node = args.np;
link->id = args.args[0];
ret = snd_soc_of_get_dai_name(cpu, &link->cpus->dai_name);
if (ret) {
if (ret != -EPROBE_DEFER)
dev_err(card->dev, "%s: error getting cpu dai name: %d\n",
link->name, ret);
goto err;
}
if (platform) {
link->platforms->of_node = of_parse_phandle(platform,
"sound-dai",
0);
if (!link->platforms->of_node) {
dev_err(card->dev, "%s: platform dai not found\n", link->name);
ret = -EINVAL;
goto err;
}
} else {
link->platforms->of_node = link->cpus->of_node;
}
if (codec) {
ret = snd_soc_of_get_dai_link_codecs(dev, codec, link);
if (ret < 0) {
if (ret != -EPROBE_DEFER)
dev_err(card->dev, "%s: codec dai not found: %d\n",
link->name, ret);
goto err;
}
if (platform) {
/* DPCM backend */
link->no_pcm = 1;
link->ignore_pmdown_time = 1;
}
} else {
/* DPCM frontend */
dlc = devm_kzalloc(dev, sizeof(*dlc), GFP_KERNEL);
if (!dlc) {
ret = -ENOMEM;
goto err;
}
link->codecs = dlc;
link->num_codecs = 1;
link->codecs->dai_name = "snd-soc-dummy-dai";
link->codecs->name = "snd-soc-dummy";
link->dynamic = 1;
}
if (platform || !codec) {
/* DPCM */
snd_soc_dai_link_set_capabilities(link);
link->ignore_suspend = 1;
link->nonatomic = 1;
}
link->stream_name = link->name;
link++;
of_node_put(cpu);
of_node_put(codec);
of_node_put(platform);
}
return 0;
err:
of_node_put(cpu);
of_node_put(codec);
of_node_put(platform);
err_put_np:
of_node_put(np);
return ret;
}
EXPORT_SYMBOL(qcom_snd_parse_of);
MODULE_LICENSE("GPL v2");