ALSA: sound/core: use memdup_user()

Remove open-coded memdup_user().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 13 insertions, 22 deletions

diff --git a/sound/core/control.c b/sound/core/control.c
index 4b20fa2b7e6d..17b8d47a5cd0 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -723,14 +723,11 @@ static int snd_ctl_elem_read_user(struct snd_card *card,
 {
         struct snd_ctl_elem_value *control;
         int result;
-        
-        control = kmalloc(sizeof(*control), GFP_KERNEL);
-        if (control == NULL)
-                return -ENOMEM; 
-        if (copy_from_user(control, _control, sizeof(*control))) {
-                kfree(control);
-                return -EFAULT;
-        }
+
+        control = memdup_user(_control, sizeof(*control));
+        if (IS_ERR(control))
+                return PTR_ERR(control);
+
         snd_power_lock(card);
         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
         if (result >= 0)
@@ -784,13 +781,10 @@ static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
         struct snd_card *card;
         int result;
 
-        control = kmalloc(sizeof(*control), GFP_KERNEL);
-        if (control == NULL)
-                return -ENOMEM; 
-        if (copy_from_user(control, _control, sizeof(*control))) {
-                kfree(control);
-                return -EFAULT;
-        }
+        control = memdup_user(_control, sizeof(*control));
+        if (IS_ERR(control))
+                return PTR_ERR(control);
+
         card = file->card;
         snd_power_lock(card);
         result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
@@ -916,13 +910,10 @@ static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
         if (op_flag > 0) {
                 if (size > 1024 * 128)  /* sane value */
                         return -EINVAL;
-                new_data = kmalloc(size, GFP_KERNEL);
-                if (new_data == NULL)
-                        return -ENOMEM;
-                if (copy_from_user(new_data, tlv, size)) {
-                        kfree(new_data);
-                        return -EFAULT;
-                }
+
+                new_data = memdup_user(tlv, size);
+                if (IS_ERR(new_data))
+                        return PTR_ERR(new_data);
                 change = ue->tlv_data_size != size;
                 if (!change)
                         change = memcmp(ue->tlv_data, new_data, size);