diff mbox series

EDAC/sysfs: Fix calling kobj_put() with ->state_initialized unset

Message ID 20231127072558.2999920-1-harshit.m.mogalapalli@oracle.com
State New
Headers
Series EDAC/sysfs: Fix calling kobj_put() with ->state_initialized unset |

Commit Message

Harshit Mogalapalli Nov. 27, 2023, 7:25 a.m. UTC 
  In edac_device_register_sysfs_main_kobj(), when dev_root is NULL,
kobject_init_and_add() is not called.

	if (err) { // err = -ENODEV
		edac_dbg(1, "Failed to register '.../edac/%s'\n",
	                 edac_dev->name);
		goto err_kobj_reg; // This calls kobj_put()
	}

This will cause a runtime warning in kobject_put() if the above happens.
Warning:
"kobject: '%s' (%p): is not initialized, yet kobject_put() is being called."

Fix the error handling to avoid the above possible situation.

Fixes: cb4a0bec0bb9 ("EDAC/sysfs: move to use bus_get_dev_root()")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
---
This is only compile tested and based on static analysis with Smatch.
---
 drivers/edac/edac_device_sysfs.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

Comments

Harshit Mogalapalli Nov. 28, 2023, 6:33 p.m. UTC | #1 
Hi,

On 27/11/23 12:55 pm, Harshit Mogalapalli wrote:
> In edac_device_register_sysfs_main_kobj(), when dev_root is NULL,
> kobject_init_and_add() is not called.
> 
> 	if (err) { // err = -ENODEV
> 		edac_dbg(1, "Failed to register '.../edac/%s'\n",
> 	                 edac_dev->name);
> 		goto err_kobj_reg; // This calls kobj_put()
> 	}
> 
> This will cause a runtime warning in kobject_put() if the above happens.
> Warning:
> "kobject: '%s' (%p): is not initialized, yet kobject_put() is being called."
> 
> Fix the error handling to avoid the above possible situation.
> 
> Fixes: cb4a0bec0bb9 ("EDAC/sysfs: move to use bus_get_dev_root()")
> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
> ---

I have sent a v2 as a patch series fixing two very similar bugs:

https://lore.kernel.org/all/20231128183037.3395755-1-harshit.m.mogalapalli@oracle.com/

> This is only compile tested and based on static analysis with Smatch.
> ---
>   drivers/edac/edac_device_sysfs.c | 14 ++++++++------
>   1 file changed, 8 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/edac/edac_device_sysfs.c b/drivers/edac/edac_device_sysfs.c
> index 010c26be5846..4cac14cbdb60 100644
> --- a/drivers/edac/edac_device_sysfs.c
> +++ b/drivers/edac/edac_device_sysfs.c
> @@ -253,11 +253,13 @@ int edac_device_register_sysfs_main_kobj(struct edac_device_ctl_info *edac_dev)
>   
>   	/* register */
>   	dev_root = bus_get_dev_root(edac_subsys);
> -	if (dev_root) {
> -		err = kobject_init_and_add(&edac_dev->kobj, &ktype_device_ctrl,
> -					   &dev_root->kobj, "%s", edac_dev->name);
> -		put_device(dev_root);
> -	}
> +	if (!dev_root)
> +		goto module_put;
> +
> +	err = kobject_init_and_add(&edac_dev->kobj, &ktype_device_ctrl,
> +				   &dev_root->kobj, "%s", edac_dev->name);
> +	put_device(dev_root);
> +
>   	if (err) {
>   		edac_dbg(1, "Failed to register '.../edac/%s'\n",
>   			 edac_dev->name);
> @@ -276,8 +278,8 @@ int edac_device_register_sysfs_main_kobj(struct edac_device_ctl_info *edac_dev)
>   	/* Error exit stack */
>   err_kobj_reg:
>   	kobject_put(&edac_dev->kobj);
> +module_put:
>   	module_put(edac_dev->owner);
> -
>   err_out:
>   	return err;
>   }
diff mbox series

Patch

diff --git a/drivers/edac/edac_device_sysfs.c b/drivers/edac/edac_device_sysfs.c
index 010c26be5846..4cac14cbdb60 100644
--- a/drivers/edac/edac_device_sysfs.c
+++ b/drivers/edac/edac_device_sysfs.c
@@ -253,11 +253,13 @@  int edac_device_register_sysfs_main_kobj(struct edac_device_ctl_info *edac_dev)
 
 	/* register */
 	dev_root = bus_get_dev_root(edac_subsys);
-	if (dev_root) {
-		err = kobject_init_and_add(&edac_dev->kobj, &ktype_device_ctrl,
-					   &dev_root->kobj, "%s", edac_dev->name);
-		put_device(dev_root);
-	}
+	if (!dev_root)
+		goto module_put;
+
+	err = kobject_init_and_add(&edac_dev->kobj, &ktype_device_ctrl,
+				   &dev_root->kobj, "%s", edac_dev->name);
+	put_device(dev_root);
+
 	if (err) {
 		edac_dbg(1, "Failed to register '.../edac/%s'\n",
 			 edac_dev->name);
@@ -276,8 +278,8 @@  int edac_device_register_sysfs_main_kobj(struct edac_device_ctl_info *edac_dev)
 	/* Error exit stack */
 err_kobj_reg:
 	kobject_put(&edac_dev->kobj);
+module_put:
 	module_put(edac_dev->owner);
-
 err_out:
 	return err;
 }