Re: [PATCH v1 1/5] devres: Introduce devm_kmemdup_array()

From: Andy Shevchenko
Date: Mon Nov 25 2024 - 02:49:39 EST


On Sun, Nov 24, 2024 at 07:03:36AM +0000, Dmitry Torokhov wrote:
> On Sun, Nov 24, 2024 at 01:35:23AM +0530, Raag Jadav wrote:
> > Introduce '_array' variant of devm_kmemdup() for the users which lack
> > multiplication overflow check.
>
> I am not sure that this new helper is needed. Unlike allocators for
> brand new objects, such as kmalloc_array(), devm_kmemdup() makes a copy
> of already existing object, which is supposed to be a valid object and
> therefore will have a reasonable size. So there should be no chance for
> hitting this overflow unless the caller is completely confused and calls
> devm_kmemdup() with random arguments (in which case all bets are off).

Don't we want to have a code more robust even if all what you say applies?
Also this makes the call consistent with zillions of others from the alloc
family of calls in the Linux kernel.

--
With Best Regards,
Andy Shevchenko