[ARM] pxa: avoid NULL dereferencing in error handling of ssp.c

The assignments of res to the results of the two calls to
platform_get_resource make it impossible to use res in the error handling
code in the arguments to release_mem_region.

The semantic match that finds the former problem is as follows:
(http://coccinelle.lip6.fr/)

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

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

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>

1 files changed, 16 insertions, 16 deletions

diff --git a/arch/arm/plat-pxa/ssp.c b/arch/arm/plat-pxa/ssp.c
index cfebcd836f3e..3bf704d7a0d6 100644
--- a/arch/arm/plat-pxa/ssp.c
+++ b/arch/arm/plat-pxa/ssp.c
@@ -92,6 +92,22 @@ static int __devinit ssp_probe(struct platform_device *pdev)
                 goto err_free;
         }
 
+        res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+        if (res == NULL) {
+                dev_err(&pdev->dev, "no SSP RX DRCMR defined\n");
+                ret = -ENODEV;
+                goto err_free_clk;
+        }
+        ssp->drcmr_rx = res->start;
+
+        res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+        if (res == NULL) {
+                dev_err(&pdev->dev, "no SSP TX DRCMR defined\n");
+                ret = -ENODEV;
+                goto err_free_clk;
+        }
+        ssp->drcmr_tx = res->start;
+
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (res == NULL) {
                 dev_err(&pdev->dev, "no memory resource defined\n");
@@ -123,22 +139,6 @@ static int __devinit ssp_probe(struct platform_device *pdev)
                 goto err_free_io;
         }
 
-        res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-        if (res == NULL) {
-                dev_err(&pdev->dev, "no SSP RX DRCMR defined\n");
-                ret = -ENODEV;
-                goto err_free_io;
-        }
-        ssp->drcmr_rx = res->start;
-
-        res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
-        if (res == NULL) {
-                dev_err(&pdev->dev, "no SSP TX DRCMR defined\n");
-                ret = -ENODEV;
-                goto err_free_io;
-        }
-        ssp->drcmr_tx = res->start;
-
         /* PXA2xx/3xx SSP ports starts from 1 and the internal pdev->id
          * starts from 0, do a translation here
          */