powerpc/fsl_rio: Add kmalloc NULL tests

Check that the result of kmalloc/kzalloc is not NULL before dereferencing it.

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

// <smpl>
@@
expression *x;
identifier f;
constant char *C;
@@

x = \(kmalloc\|kcalloc\|kzalloc\)(...);
... when != x == NULL
    when != x != NULL
    when != (x || ...)
(
kfree(x)
|
f(...,C,...,x,...)
|
*f(...,x,...)
|
*x->f
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 14 insertions, 4 deletions

diff --git a/arch/powerpc/sysdev/fsl_rio.c b/arch/powerpc/sysdev/fsl_rio.c
index cbb3bed75d3c..757a83fe5e59 100644
--- a/arch/powerpc/sysdev/fsl_rio.c
+++ b/arch/powerpc/sysdev/fsl_rio.c
@@ -1057,6 +1057,10 @@ int fsl_rio_setup(struct of_device *dev)
                         law_start, law_size);
 
         ops = kmalloc(sizeof(struct rio_ops), GFP_KERNEL);
+        if (!ops) {
+                rc = -ENOMEM;
+                goto err_ops;
+        }
         ops->lcread = fsl_local_config_read;
         ops->lcwrite = fsl_local_config_write;
         ops->cread = fsl_rio_config_read;
@@ -1064,6 +1068,10 @@ int fsl_rio_setup(struct of_device *dev)
         ops->dsend = fsl_rio_doorbell_send;
 
         port = kzalloc(sizeof(struct rio_mport), GFP_KERNEL);
+        if (!port) {
+                rc = -ENOMEM;
+                goto err_port;
+        }
         port->id = 0;
         port->index = 0;
 
@@ -1071,7 +1079,7 @@ int fsl_rio_setup(struct of_device *dev)
         if (!priv) {
                 printk(KERN_ERR "Can't alloc memory for 'priv'\n");
                 rc = -ENOMEM;
-                goto err;
+                goto err_priv;
         }
 
         INIT_LIST_HEAD(&port->dbells);
@@ -1169,11 +1177,13 @@ int fsl_rio_setup(struct of_device *dev)
 
         return 0;
 err:
-        if (priv)
-                iounmap(priv->regs_win);
-        kfree(ops);
+        iounmap(priv->regs_win);
         kfree(priv);
+err_priv:
         kfree(port);
+err_port:
+        kfree(ops);
+err_ops:
         return rc;
 }