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Diffstat (limited to 'sound/core/oss/pcm_oss.c')
-rw-r--r--sound/core/oss/pcm_oss.c31
1 files changed, 22 insertions, 9 deletions
diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index 58550cc93f28..ebc9fdfe64df 100644
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -33,6 +33,7 @@
#include <linux/module.h>
#include <linux/math64.h>
#include <linux/string.h>
+#include <linux/compat.h>
#include <sound/core.h>
#include <sound/minors.h>
#include <sound/pcm.h>
@@ -834,7 +835,8 @@ static int choose_rate(struct snd_pcm_substream *substream,
return snd_pcm_hw_param_near(substream, params, SNDRV_PCM_HW_PARAM_RATE, best_rate, NULL);
}
-static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream)
+static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream,
+ bool trylock)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct snd_pcm_hw_params *params, *sparams;
@@ -848,9 +850,12 @@ static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream)
struct snd_mask sformat_mask;
struct snd_mask mask;
- if (mutex_lock_interruptible(&runtime->oss.params_lock))
+ if (trylock) {
+ if (!(mutex_trylock(&runtime->oss.params_lock)))
+ return -EAGAIN;
+ } else if (mutex_lock_interruptible(&runtime->oss.params_lock))
return -EINTR;
- sw_params = kmalloc(sizeof(*sw_params), GFP_KERNEL);
+ sw_params = kzalloc(sizeof(*sw_params), GFP_KERNEL);
params = kmalloc(sizeof(*params), GFP_KERNEL);
sparams = kmalloc(sizeof(*sparams), GFP_KERNEL);
if (!sw_params || !params || !sparams) {
@@ -988,7 +993,6 @@ static int snd_pcm_oss_change_params(struct snd_pcm_substream *substream)
goto failure;
}
- memset(sw_params, 0, sizeof(*sw_params));
if (runtime->oss.trigger) {
sw_params->start_threshold = 1;
} else {
@@ -1092,7 +1096,7 @@ static int snd_pcm_oss_get_active_substream(struct snd_pcm_oss_file *pcm_oss_fil
if (asubstream == NULL)
asubstream = substream;
if (substream->runtime->oss.params) {
- err = snd_pcm_oss_change_params(substream);
+ err = snd_pcm_oss_change_params(substream, false);
if (err < 0)
return err;
}
@@ -1132,7 +1136,7 @@ static int snd_pcm_oss_make_ready(struct snd_pcm_substream *substream)
return 0;
runtime = substream->runtime;
if (runtime->oss.params) {
- err = snd_pcm_oss_change_params(substream);
+ err = snd_pcm_oss_change_params(substream, false);
if (err < 0)
return err;
}
@@ -2163,7 +2167,7 @@ static int snd_pcm_oss_get_space(struct snd_pcm_oss_file *pcm_oss_file, int stre
runtime = substream->runtime;
if (runtime->oss.params &&
- (err = snd_pcm_oss_change_params(substream)) < 0)
+ (err = snd_pcm_oss_change_params(substream, false)) < 0)
return err;
info.fragsize = runtime->oss.period_bytes;
@@ -2648,7 +2652,11 @@ static long snd_pcm_oss_ioctl(struct file *file, unsigned int cmd, unsigned long
#ifdef CONFIG_COMPAT
/* all compatible */
-#define snd_pcm_oss_ioctl_compat snd_pcm_oss_ioctl
+static long snd_pcm_oss_ioctl_compat(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ return snd_pcm_oss_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+}
#else
#define snd_pcm_oss_ioctl_compat NULL
#endif
@@ -2800,7 +2808,12 @@ static int snd_pcm_oss_mmap(struct file *file, struct vm_area_struct *area)
return -EIO;
if (runtime->oss.params) {
- if ((err = snd_pcm_oss_change_params(substream)) < 0)
+ /* use mutex_trylock() for params_lock for avoiding a deadlock
+ * between mmap_sem and params_lock taken by
+ * copy_from/to_user() in snd_pcm_oss_write/read()
+ */
+ err = snd_pcm_oss_change_params(substream, true);
+ if (err < 0)
return err;
}
#ifdef CONFIG_SND_PCM_OSS_PLUGINS