Re: [PATCH] EDAC/sysfs: Fix calling kobject_put() without kobj initialization

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Nov 28, 2023 at 05:09:52AM -0800, Harshit Mogalapalli wrote:
> In edac_pci_main_kobj_setup() when dev_root is NULL,
> kobject_init_and_add() is not called.
> 
>         if (err) { // err = -ENODEV;
>                 edac_dbg(1, "Failed to register '.../edac/pci'\n");
>                 goto kobject_init_and_add_fail; // call to kobject_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 based on static analysis with Smatch and only compile tested.
> ---
>  drivers/edac/edac_pci_sysfs.c | 14 ++++++++------
>  1 file changed, 8 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/edac/edac_pci_sysfs.c b/drivers/edac/edac_pci_sysfs.c
> index 901d4cd3ca38..71a0d4b9c2cf 100644
> --- a/drivers/edac/edac_pci_sysfs.c
> +++ b/drivers/edac/edac_pci_sysfs.c
> @@ -370,12 +370,14 @@ static int edac_pci_main_kobj_setup(void)
>  
>  	/* Instanstiate the pci object */
>  	dev_root = bus_get_dev_root(edac_subsys);
> -	if (dev_root) {
> -		err = kobject_init_and_add(edac_pci_top_main_kobj,
> -					   &ktype_edac_pci_main_kobj,
> -					   &dev_root->kobj, "pci");
> -		put_device(dev_root);
> -	}
> +	if (!dev_root)
> +		goto kzalloc_fail;
> +
> +	err = kobject_init_and_add(edac_pci_top_main_kobj,
> +				   &ktype_edac_pci_main_kobj,
> +				   &dev_root->kobj, "pci");
> +	put_device(dev_root);
> +
>  	if (err) {
>  		edac_dbg(1, "Failed to register '.../edac/pci'\n");
>  		goto kobject_init_and_add_fail;
> -- 
> 2.39.3
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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