Re: [PATCH] kobject_set_name_vargs memory leak

[Greg KH <gregkh@suse.de>]

On Fri, Jun 26, 2009 at 05:36:52PM +0300, Sergey Senozhatsky wrote:
> Hello.
> I suppose this patch fixes memory leak in kobject.c
> Correct me if I'm wrong.
> Thanks.
> -----------
> 
> Fix memory leak when kobject_set_name_vargs returns -ENOMEM.
> 
> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@mail.by>
> ---
> diff --git a/lib/kobject.c b/lib/kobject.c
> index b512b74..922cd8c 100644
> --- a/lib/kobject.c
> +++ b/lib/kobject.c
> @@ -222,8 +222,10 @@ int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
>  		return 0;
>  
>  	kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs);
> -	if (!kobj->name)
> +	if (!kobj->name) {
> +		kfree(old_name);
>  		return -ENOMEM;
> +	}

We've been through this before (search lkml archives).  If kvasprintf
fails, then we don't want to free old_name, as the caller might want to
do something with it.

Or something along those lines, I can't remember the exact reasoning
this early in the morning.

Kay, do you remember?

thanks,

greg k-h