return -EFAULT;
 
        buffer_size = depth->n * sizeof(u32);
-       buffer = kmalloc(buffer_size, GFP_KERNEL);
-       if (buffer == NULL)
-               return -ENOMEM;
-       if (copy_from_user(buffer, depth->buffer, buffer_size)) {
-               kfree(buffer);
-               return -EFAULT;
-       }
+       buffer = memdup_user(depth->buffer, buffer_size);
+       if (IS_ERR(buffer))
+               return PTR_ERR(buffer);
 
        mask_size = depth->n * sizeof(u8);
        if (depth->mask) {
-               mask = kmalloc(mask_size, GFP_KERNEL);
-               if (mask == NULL) {
+               mask = memdup_user(depth->mask, mask_size);
+               if (IS_ERR(mask)) {
                        kfree(buffer);
-                       return -ENOMEM;
-               }
-               if (copy_from_user(mask, depth->mask, mask_size)) {
-                       kfree(buffer);
-                       kfree(mask);
-                       return -EFAULT;
+                       return PTR_ERR(mask);
                }
 
                for (i = 0; i < count; i++, x++) {
        }
 
        buffer_size = depth->n * sizeof(u32);
-       buffer = kmalloc(buffer_size, GFP_KERNEL);
-       if (buffer == NULL) {
-               kfree(x);
-               kfree(y);
-               return -ENOMEM;
-       }
-       if (copy_from_user(buffer, depth->buffer, buffer_size)) {
+       buffer = memdup_user(depth->buffer, buffer_size);
+       if (IS_ERR(buffer)) {
                kfree(x);
                kfree(y);
-               kfree(buffer);
-               return -EFAULT;
+               return PTR_ERR(buffer);
        }
 
        if (depth->mask) {
                mask_size = depth->n * sizeof(u8);
-               mask = kmalloc(mask_size, GFP_KERNEL);
-               if (mask == NULL) {
-                       kfree(x);
-                       kfree(y);
-                       kfree(buffer);
-                       return -ENOMEM;
-               }
-               if (copy_from_user(mask, depth->mask, mask_size)) {
+               mask = memdup_user(depth->mask, mask_size);
+               if (IS_ERR(mask)) {
                        kfree(x);
                        kfree(y);
                        kfree(buffer);
-                       kfree(mask);
-                       return -EFAULT;
+                       return PTR_ERR(mask);
                }
 
                for (i = 0; i < count; i++) {