vhost_vdpa: switch to vmemdup_user()

Replace opencoded alloc and copy with vmemdup_user()

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1605057288-60400-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 29ed417..ef688c8 100644 (file)
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -245,14 +245,10 @@ static long vhost_vdpa_set_config(struct vhost_vdpa *v,
                return -EFAULT;
        if (vhost_vdpa_config_validate(v, &config))
                return -EINVAL;
-       buf = kvzalloc(config.len, GFP_KERNEL);
-       if (!buf)
-               return -ENOMEM;
 
-       if (copy_from_user(buf, c->buf, config.len)) {
-               kvfree(buf);
-               return -EFAULT;
-       }
+       buf = vmemdup_user(c->buf, config.len);
+       if (IS_ERR(buf))
+               return PTR_ERR(buf);
 
        ops->set_config(vdpa, config.off, buf, config.len);