staging/easycap: Use memdup_user

 Use kmemdup_user rather than duplicating its implementation
 This is a little bit restricted to reduce false positives

 The semantic patch that makes this output is available
 in scripts/coccinelle/api/memdup_user.cocci.

 More information about semantic patching is available at
 http://coccinelle.lip6.fr/

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/easycap/easycap_ioctl.c b/drivers/staging/easycap/easycap_ioctl.c
index 0accab97a7f601a8233ca6174669f52b0b7b1a70..91262fbd69e2446bb2275d5386425f16f9980de8 100644 (file)
--- a/drivers/staging/easycap/easycap_ioctl.c
+++ b/drivers/staging/easycap/easycap_ioctl.c
@@ -1317,17 +1317,12 @@ long easycap_unlocked_ioctl(struct file *file,
                struct v4l2_control *pv4l2_control;
 
                JOM(8, "VIDIOC_G_CTRL\n");
-               pv4l2_control = kzalloc(sizeof(struct v4l2_control), GFP_KERNEL);
-               if (!pv4l2_control) {
-                       SAM("ERROR: out of memory\n");
+               pv4l2_control = memdup_user((void __user *)arg,
+                                           sizeof(struct v4l2_control));
+               if (IS_ERR(pv4l2_control)) {
+                       SAM("ERROR: copy from user failed\n");
                        mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
-                       return -ENOMEM;
-               }
-               if (0 != copy_from_user(pv4l2_control, (void __user *)arg,
-                               sizeof(struct v4l2_control))) {
-                       kfree(pv4l2_control);
-                       mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
-                       return -EFAULT;
+                       return PTR_ERR(pv4l2_control);
                }
 
                switch (pv4l2_control->id) {
@@ -2356,17 +2351,12 @@ long easycap_unlocked_ioctl(struct file *file,
                struct v4l2_streamparm *pv4l2_streamparm;
 
                JOM(8, "VIDIOC_G_PARM\n");
-               pv4l2_streamparm = kzalloc(sizeof(struct v4l2_streamparm), GFP_KERNEL);
-               if (!pv4l2_streamparm) {
-                       SAM("ERROR: out of memory\n");
-                       mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
-                       return -ENOMEM;
-               }
-               if (copy_from_user(pv4l2_streamparm,
-                       (void __user *)arg, sizeof(struct v4l2_streamparm))) {
-                       kfree(pv4l2_streamparm);
+               pv4l2_streamparm = memdup_user((void __user *)arg,
+                                              sizeof(struct v4l2_streamparm));
+               if (IS_ERR(pv4l2_streamparm)) {
+                       SAM("ERROR: copy from user failed\n");
                        mutex_unlock(&easycapdc60_dongle[kd].mutex_video);
-                       return -EFAULT;
+                       return PTR_ERR(pv4l2_streamparm);
                }
 
                if (pv4l2_streamparm->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) {