[alsa-devel] [PATCH 18/20] ALSA: hda - Protect user-defined arrays via mutex
Takashi Iwai
tiwai at suse.de
Tue Jan 15 12:05:45 CET 2013
The pincfgs, init_verbs and hints set by sysfs or patch might be
changed dynamically on the fly, thus we need to protect it.
Add a simple protection via a mutex.
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
sound/pci/hda/hda_codec.c | 13 ++++++--
sound/pci/hda/hda_codec.h | 1 +
sound/pci/hda/hda_hwdep.c | 67 ++++++++++++++++++++++++++++++------------
sound/pci/hda/patch_sigmatel.c | 5 ++++
4 files changed, 65 insertions(+), 21 deletions(-)
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 0a531f2..b28e403 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -1086,9 +1086,16 @@ unsigned int snd_hda_codec_get_pincfg(struct hda_codec *codec, hda_nid_t nid)
struct hda_pincfg *pin;
#ifdef CONFIG_SND_HDA_HWDEP
- pin = look_up_pincfg(codec, &codec->user_pins, nid);
- if (pin)
- return pin->cfg;
+ {
+ unsigned int cfg = 0;
+ mutex_lock(&codec->user_mutex);
+ pin = look_up_pincfg(codec, &codec->user_pins, nid);
+ if (pin)
+ cfg = pin->cfg;
+ mutex_unlock(&codec->user_mutex);
+ if (cfg)
+ return cfg;
+ }
#endif
pin = look_up_pincfg(codec, &codec->driver_pins, nid);
if (pin)
diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h
index 4c4f166..61085b3 100644
--- a/sound/pci/hda/hda_codec.h
+++ b/sound/pci/hda/hda_codec.h
@@ -845,6 +845,7 @@ struct hda_codec {
struct snd_array cvt_setups; /* audio convert setups */
#ifdef CONFIG_SND_HDA_HWDEP
+ struct mutex user_mutex;
struct snd_hwdep *hwdep; /* assigned hwdep device */
struct snd_array init_verbs; /* additional init verbs */
struct snd_array hints; /* additional hints */
diff --git a/sound/pci/hda/hda_hwdep.c b/sound/pci/hda/hda_hwdep.c
index a5c9411..2dddf7f 100644
--- a/sound/pci/hda/hda_hwdep.c
+++ b/sound/pci/hda/hda_hwdep.c
@@ -148,6 +148,7 @@ int snd_hda_create_hwdep(struct hda_codec *codec)
hwdep->ops.ioctl_compat = hda_hwdep_ioctl_compat;
#endif
+ mutex_init(&codec->user_mutex);
snd_array_init(&codec->init_verbs, sizeof(struct hda_verb), 32);
snd_array_init(&codec->hints, sizeof(struct hda_hint), 32);
snd_array_init(&codec->user_pins, sizeof(struct hda_pincfg), 16);
@@ -346,12 +347,14 @@ static ssize_t init_verbs_show(struct device *dev,
struct snd_hwdep *hwdep = dev_get_drvdata(dev);
struct hda_codec *codec = hwdep->private_data;
int i, len = 0;
+ mutex_lock(&codec->user_mutex);
for (i = 0; i < codec->init_verbs.used; i++) {
struct hda_verb *v = snd_array_elem(&codec->init_verbs, i);
len += snprintf(buf + len, PAGE_SIZE - len,
"0x%02x 0x%03x 0x%04x\n",
v->nid, v->verb, v->param);
}
+ mutex_unlock(&codec->user_mutex);
return len;
}
@@ -364,12 +367,16 @@ static int parse_init_verbs(struct hda_codec *codec, const char *buf)
return -EINVAL;
if (!nid || !verb)
return -EINVAL;
+ mutex_lock(&codec->user_mutex);
v = snd_array_new(&codec->init_verbs);
- if (!v)
+ if (!v) {
+ mutex_unlock(&codec->user_mutex);
return -ENOMEM;
+ }
v->nid = nid;
v->verb = verb;
v->param = param;
+ mutex_unlock(&codec->user_mutex);
return 0;
}
@@ -392,11 +399,13 @@ static ssize_t hints_show(struct device *dev,
struct snd_hwdep *hwdep = dev_get_drvdata(dev);
struct hda_codec *codec = hwdep->private_data;
int i, len = 0;
+ mutex_lock(&codec->user_mutex);
for (i = 0; i < codec->hints.used; i++) {
struct hda_hint *hint = snd_array_elem(&codec->hints, i);
len += snprintf(buf + len, PAGE_SIZE - len,
"%s = %s\n", hint->key, hint->val);
}
+ mutex_unlock(&codec->user_mutex);
return len;
}
@@ -431,6 +440,7 @@ static int parse_hints(struct hda_codec *codec, const char *buf)
{
char *key, *val;
struct hda_hint *hint;
+ int err = 0;
buf = skip_spaces(buf);
if (!*buf || *buf == '#' || *buf == '\n')
@@ -450,26 +460,31 @@ static int parse_hints(struct hda_codec *codec, const char *buf)
val = skip_spaces(val);
remove_trail_spaces(key);
remove_trail_spaces(val);
+ mutex_lock(&codec->user_mutex);
hint = get_hint(codec, key);
if (hint) {
/* replace */
kfree(hint->key);
hint->key = key;
hint->val = val;
- return 0;
+ goto unlock;
}
/* allocate a new hint entry */
if (codec->hints.used >= MAX_HINTS)
hint = NULL;
else
hint = snd_array_new(&codec->hints);
- if (!hint) {
- kfree(key);
- return -ENOMEM;
+ if (hint) {
+ hint->key = key;
+ hint->val = val;
+ } else {
+ err = -ENOMEM;
}
- hint->key = key;
- hint->val = val;
- return 0;
+ unlock:
+ mutex_unlock(&codec->user_mutex);
+ if (err)
+ kfree(key);
+ return err;
}
static ssize_t hints_store(struct device *dev,
@@ -489,11 +504,13 @@ static ssize_t pin_configs_show(struct hda_codec *codec,
char *buf)
{
int i, len = 0;
+ mutex_lock(&codec->user_mutex);
for (i = 0; i < list->used; i++) {
struct hda_pincfg *pin = snd_array_elem(list, i);
len += sprintf(buf + len, "0x%02x 0x%08x\n",
pin->nid, pin->cfg);
}
+ mutex_unlock(&codec->user_mutex);
return len;
}
@@ -528,13 +545,16 @@ static ssize_t driver_pin_configs_show(struct device *dev,
static int parse_user_pin_configs(struct hda_codec *codec, const char *buf)
{
- int nid, cfg;
+ int nid, cfg, err;
if (sscanf(buf, "%i %i", &nid, &cfg) != 2)
return -EINVAL;
if (!nid)
return -EINVAL;
- return snd_hda_add_pincfg(codec, &codec->user_pins, nid, cfg);
+ mutex_lock(&codec->user_mutex);
+ err = snd_hda_add_pincfg(codec, &codec->user_pins, nid, cfg);
+ mutex_unlock(&codec->user_mutex);
+ return err;
}
static ssize_t user_pin_configs_store(struct device *dev,
@@ -600,16 +620,27 @@ EXPORT_SYMBOL_HDA(snd_hda_get_hint);
int snd_hda_get_bool_hint(struct hda_codec *codec, const char *key)
{
- const char *p = snd_hda_get_hint(codec, key);
+ const char *p;
+ int ret;
+
+ mutex_lock(&codec->user_mutex);
+ p = snd_hda_get_hint(codec, key);
if (!p || !*p)
- return -ENOENT;
- switch (toupper(*p)) {
- case 'T': /* true */
- case 'Y': /* yes */
- case '1':
- return 1;
+ ret = -ENOENT;
+ else {
+ switch (toupper(*p)) {
+ case 'T': /* true */
+ case 'Y': /* yes */
+ case '1':
+ ret = 1;
+ break;
+ default:
+ ret = 0;
+ break;
+ }
}
- return 0;
+ mutex_unlock(&codec->user_mutex);
+ return ret;
}
EXPORT_SYMBOL_HDA(snd_hda_get_bool_hint);
diff --git a/sound/pci/hda/patch_sigmatel.c b/sound/pci/hda/patch_sigmatel.c
index a86547c..d3a81f1 100644
--- a/sound/pci/hda/patch_sigmatel.c
+++ b/sound/pci/hda/patch_sigmatel.c
@@ -4298,15 +4298,20 @@ static void stac_toggle_power_map(struct hda_codec *codec, hda_nid_t nid,
static inline int get_int_hint(struct hda_codec *codec, const char *key,
int *valp)
{
+#ifdef CONFIG_SND_HDA_RECONFIG
const char *p;
+ mutex_lock(&codec->user_mutex);
p = snd_hda_get_hint(codec, key);
if (p) {
unsigned long val;
if (!strict_strtoul(p, 0, &val)) {
*valp = val;
+ mutex_unlock(&codec->user_mutex);
return 1;
}
}
+ mutex_unlock(&codec->user_mutex);
+#endif
return 0;
}
--
1.8.1
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