Re: [PATCH -next] nvmem: core: Fix memleak in nvmem_register()

[Greg KH]

On Sat, Jul 16, 2022 at 03:53:52PM +0800, Gaosheng Cui wrote:
> dev_set_name will alloc memory for nvmem->dev.kobj.name in
> nvmem_register, when nvmem_validate_keepouts failed, nvmem's
> memory will be freed and return, but nobody will free memory
> for nvmem->dev.kobj.name, there will be memleak, so using
> kfree_const(nvmem->dev.kobj.name) to fix it.
> 
> Fixes: de0534df9347 ("nvmem: core: fix error handling while validating keepout regions")
> Signed-off-by: Gaosheng Cui <cuigaosheng1@xxxxxxxxxx>
> ---
>  drivers/nvmem/core.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
> index 1e3c754efd0d..6c75c9afa5f3 100644
> --- a/drivers/nvmem/core.c
> +++ b/drivers/nvmem/core.c
> @@ -833,6 +833,7 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
>  		rval = nvmem_validate_keepouts(nvmem);
>  		if (rval) {
>  			ida_free(&nvmem_ida, nvmem->id);
> +			kfree_const(nvmem->dev.kobj.name);
>  			kfree(nvmem);

Something is really wrong, you should never be touching the name pointer
of a kobject directly like this.  Also the device structure itself
should be cleaning up the memory, not a kfree.  So this feels wrong...

greg k-h