V4L/DVB: drivers/media: Eliminate a NULL pointer dereference
authorJulia Lawall <julia@diku.dk>
Thu, 27 May 2010 12:36:45 +0000 (09:36 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Tue, 1 Jun 2010 04:24:22 +0000 (01:24 -0300)
In each case, the print involves dereferencing a value that is NULL or is
near NULL.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
expression E,E1;
identifier f;
statement S1,S2,S3;
@@

if ((E == NULL && ...) || ...)
{
  ... when != if (...) S1 else S2
      when != E = E1
* E->f
  ... when any
  return ...;
}
else S3
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
drivers/media/dvb/firewire/firedtv-1394.c
drivers/media/video/hdpvr/hdpvr-video.c
drivers/media/video/usbvision/usbvision-video.c

index 26333b4..b34ca7a 100644 (file)
@@ -58,7 +58,7 @@ static void rawiso_activity_cb(struct hpsb_iso *iso)
        num = hpsb_iso_n_ready(iso);
 
        if (!fdtv) {
-               dev_err(fdtv->device, "received at unknown iso channel\n");
+               pr_err("received at unknown iso channel\n");
                goto out;
        }
 
index 7cfccfd..c338f3f 100644 (file)
@@ -366,7 +366,7 @@ static int hdpvr_open(struct file *file)
 
        dev = (struct hdpvr_device *)video_get_drvdata(video_devdata(file));
        if (!dev) {
-               v4l2_err(&dev->v4l2_dev, "open failing with with ENODEV\n");
+               pr_err("open failing with with ENODEV\n");
                retval = -ENODEV;
                goto err;
        }
index 6248a63..c2690df 100644 (file)
@@ -1671,8 +1671,7 @@ static void __devexit usbvision_disconnect(struct usb_interface *intf)
        PDEBUG(DBG_PROBE, "");
 
        if (usbvision == NULL) {
-               dev_err(&usbvision->dev->dev,
-                       "%s: usb_get_intfdata() failed\n", __func__);
+               pr_err("%s: usb_get_intfdata() failed\n", __func__);
                return;
        }