drm/i915: use memdup_user_nul

Use memdup_user_nul() helper instead of open-coding to simplify the
code.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/6baf3aa45d0b5e0fd016b508bac905ebf8443aac.1493779294.git.geliangtang@gmail.com

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 870c470..1003511 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -3702,16 +3702,10 @@ static ssize_t i915_displayport_test_active_write(struct file *file,
        if (len == 0)
                return 0;
 
-       input_buffer = kmalloc(len + 1, GFP_KERNEL);
-       if (!input_buffer)
-               return -ENOMEM;
+       input_buffer = memdup_user_nul(ubuf, len);
+       if (IS_ERR(input_buffer))
+               return PTR_ERR(input_buffer);
 
-       if (copy_from_user(input_buffer, ubuf, len)) {
-               status = -EFAULT;
-               goto out;
-       }
-
-       input_buffer[len] = '\0';
        DRM_DEBUG_DRIVER("Copied %d bytes from user\n", (unsigned int)len);
 
        drm_connector_list_iter_begin(dev, &conn_iter);
@@ -3737,7 +3731,6 @@ static ssize_t i915_displayport_test_active_write(struct file *file,
                }
        }
        drm_connector_list_iter_end(&conn_iter);
-out:
        kfree(input_buffer);
        if (status < 0)
                return status;

diff --git a/drivers/gpu/drm/i915/intel_pipe_crc.c b/drivers/gpu/drm/i915/intel_pipe_crc.c
index 647426c..8fbd2bd 100644 (file)
--- a/drivers/gpu/drm/i915/intel_pipe_crc.c
+++ b/drivers/gpu/drm/i915/intel_pipe_crc.c
@@ -853,19 +853,12 @@ static ssize_t display_crc_ctl_write(struct file *file, const char __user *ubuf,
                return -E2BIG;
        }
 
-       tmpbuf = kmalloc(len + 1, GFP_KERNEL);
-       if (!tmpbuf)
-               return -ENOMEM;
-
-       if (copy_from_user(tmpbuf, ubuf, len)) {
-               ret = -EFAULT;
-               goto out;
-       }
-       tmpbuf[len] = '\0';
+       tmpbuf = memdup_user_nul(ubuf, len);
+       if (IS_ERR(tmpbuf))
+               return PTR_ERR(tmpbuf);
 
        ret = display_crc_ctl_parse(dev_priv, tmpbuf, len);
 
-out:
        kfree(tmpbuf);
        if (ret < 0)
                return ret;