[PATCH] drm/i915: use memdup_user_nul

Geliang Tang
2017-05-06T15:40:35Z

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

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
---
drivers/gpu/drm/i915/i915_debugfs.c | 13 +++----------
drivers/gpu/drm/i915/intel_pipe_crc.c | 13 +++----------
2 files changed, 6 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index d689e51..e56b636 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -3704,16 +3704,10 @@ 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);
@@ -3739,7 +3733,6 @@ 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 206ee4f..813dd3c 100644
--- a/drivers/gpu/drm/i915/intel_pipe_crc.c
+++ b/drivers/gpu/drm/i915/intel_pipe_crc.c
@@ -842,19 +842,12 @@ 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;
--
2.9.3