[PATCH resent v2 2/2] powerpc/pseries: Fix exception handling in pSeries_reconfig_add_node()

[Markus Elfring]

Date: Tue, 21 Mar 2023 10:50:08 +0100

The label “out_err” was used to jump to another pointer check despite of
the detail in the implementation of the function “pSeries_reconfig_add_node”
that it was determined already that the corresponding variable contained
a null pointer (because of a failed function call in two cases).

1. Thus return directly after a call of the function “kzalloc” failed.

2. Use more appropriate labels instead.

3. Delete a redundant check.

4. Omit an explicit initialisation for the local variable “err”.

This issue was detected by using the Coccinelle software.

Fixes: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ("Linux-2.6.12-rc2")
Signed-off-by: Markus Elfring <elfr...@users.sourceforge.net>
---
V2:
This update step was based on a previous change.

 arch/powerpc/platforms/pseries/reconfig.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/reconfig.c 
b/arch/powerpc/platforms/pseries/reconfig.c
index 44f8ebc2ec0d..14154f48ef63 100644
--- a/arch/powerpc/platforms/pseries/reconfig.c
+++ b/arch/powerpc/platforms/pseries/reconfig.c
@@ -23,15 +23,17 @@
 static int pSeries_reconfig_add_node(const char *path, struct property 
*proplist)
 {
        struct device_node *np;
-       int err = -ENOMEM;
+       int err;

        np = kzalloc(sizeof(*np), GFP_KERNEL);
        if (!np)
-               goto out_err;
+               return -ENOMEM;

        np->full_name = kstrdup(kbasename(path), GFP_KERNEL);
-       if (!np->full_name)
-               goto out_err;
+       if (!np->full_name) {
+               err = -ENOMEM;
+               goto free_device_node;
+       }

        np->properties = proplist;
        of_node_set_flag(np, OF_DYNAMIC);
@@ -46,20 +48,19 @@ static int pSeries_reconfig_add_node(const char *path, 
struct property *proplist
        err = of_attach_node(np);
        if (err) {
                printk(KERN_ERR "Failed to add device node %s\n", path);
-               goto out_err;
+               goto put_node;
        }

        of_node_put(np->parent);

        return 0;

-out_err:
-       if (np) {
-               of_node_put(np->parent);
+put_node:
+       of_node_put(np->parent);
 free_name:
-               kfree(np->full_name);
-               kfree(np);
-       }
+       kfree(np->full_name);
+free_device_node:
+       kfree(np);
        return err;
 }

--
2.40.0