From: Julia Lawall <julia@diku.dk>
Date: Fri, 28 Oct 2011 22:58:17 +0000 (-0300)
Subject: [media] drivers/media/video/davinci/vpbe_display.c: eliminate a null pointer dereference
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=49a0513c1fca2c43b14416f3f40220fa01ab5e39;p=deliverable%2Flinux.git

[media] drivers/media/video/davinci/vpbe_display.c: eliminate a null pointer dereference

In the original code, probe_out could be reached when res was null and then
when the irq had not yet been requested.  In those cases, the call to
free_irq is not needed, so move probe_out down and introduce a new label
for the case where calling free_irq is useful.

The semantic match that finds this problem is as follows:

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

if (E == NULL)
{
  ... when != if (E == NULL || ...) 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>
---

diff --git a/drivers/media/video/davinci/vpbe_display.c b/drivers/media/video/davinci/vpbe_display.c
index 8588a86d9b45..d98da4bfb256 100644
--- a/drivers/media/video/davinci/vpbe_display.c
+++ b/drivers/media/video/davinci/vpbe_display.c
@@ -1746,15 +1746,16 @@ static __devinit int vpbe_display_probe(struct platform_device *pdev)
 	for (i = 0; i < VPBE_DISPLAY_MAX_DEVICES; i++) {
 		if (register_device(disp_dev->dev[i], disp_dev, pdev)) {
 			err = -ENODEV;
-			goto probe_out;
+			goto probe_out_irq;
 		}
 	}
 
 	printk(KERN_DEBUG "Successfully completed the probing of vpbe v4l2 device\n");
 	return 0;
 
-probe_out:
+probe_out_irq:
 	free_irq(res->start, disp_dev);
+probe_out:
 	for (k = 0; k < VPBE_DISPLAY_MAX_DEVICES; k++) {
 		/* Get the pointer to the layer object */
 		vpbe_display_layer = disp_dev->dev[k];