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

[cuigaosheng]

Thanks for your time.

I have made the v2 patch and moving dev_set_name after nvmem_validate_keepouts
to fix the issue, hope you can provide some advice.

Thanks.

在 2022/7/16 16:23, Greg KH 写道:
> 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
> .