ASoC: wm_adsp: Use vmemdup_user() instead of open-coding

Use vmemdup_user() to get a copy of the user buffer in wm_coeff_tlv_put().

Apart from simplifying the code and avoiding open-coding, it means we
also automatically benefit from any security enhancements in the code
behind vmemdup_user().

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://patch.msgid.link/20250410101812.1180539-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c
index ffd826f30e155b516604212ddc77963ab54477f1..a2e9f32209cfddeb3af28a2d8375646e14beb084 100644 (file)
--- a/sound/soc/codecs/wm_adsp.c
+++ b/sound/soc/codecs/wm_adsp.c
@@ -8,6 +8,7 @@
  */
 
 #include <linux/array_size.h>
+#include <linux/cleanup.h>
 #include <linux/ctype.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
@@ -19,7 +20,7 @@
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
-#include <linux/vmalloc.h>
+#include <linux/string.h>
 #include <linux/workqueue.h>
 #include <linux/debugfs.h>
 #include <sound/core.h>
@@ -415,21 +416,12 @@ static int wm_coeff_tlv_put(struct snd_kcontrol *kctl,
                (struct soc_bytes_ext *)kctl->private_value;
        struct wm_coeff_ctl *ctl = bytes_ext_to_ctl(bytes_ext);
        struct cs_dsp_coeff_ctl *cs_ctl = ctl->cs_ctl;
-       void *scratch;
-       int ret = 0;
+       void *scratch __free(kvfree) = vmemdup_user(bytes, size);
 
-       scratch = vmalloc(size);
-       if (!scratch)
-               return -ENOMEM;
+       if (IS_ERR(scratch))
+               return PTR_ERR(no_free_ptr(scratch));
 
-       if (copy_from_user(scratch, bytes, size))
-               ret = -EFAULT;
-       else
-               ret = cs_dsp_coeff_lock_and_write_ctrl(cs_ctl, 0, scratch, size);
-
-       vfree(scratch);
-
-       return ret;
+       return cs_dsp_coeff_lock_and_write_ctrl(cs_ctl, 0, scratch, size);
 }
 
 static int wm_coeff_put_acked(struct snd_kcontrol *kctl,