Re: [PATCH v4 08/12] device core: Introduce multiple dma pfn offsets

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Jim Quinlan <james.quinlan@broadcom.com>
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Subject: Re: [PATCH v4 08/12] device core: Introduce multiple dma pfn offsets
Date: Tue, 9 Jun 2020 14:18:28 +0300	[thread overview]
Message-ID: <20200609111828.GI2428291@smile.fi.intel.com> (raw)
In-Reply-To: <CA+-6iNyL12Z+igSrWnsmTzrwzyyeDtSK-9ULiZe0MwM5LO5bjQ@mail.gmail.com>

On Mon, Jun 08, 2020 at 11:48:51AM -0400, Jim Quinlan wrote:
> On Sun, Jun 7, 2020 at 12:500f9bfe0fb8840b268af1bbcc51f1cd440514e PM
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> > On Fri, Jun 05, 2020 at 05:26:48PM -0400, Jim Quinlan wrote:

...

> > > +     *map_size = (num_ranges + 1) * sizeof(**map);
> > > +     r = kzalloc(*map_size, GFP_KERNEL);
> >
> > kcalloc()
> Since I have to calculate the size anyway I thought kzalloc was fine.
> I'll switch.

The point is to check multiplication overflow. See overflow.h for helpers.

> > > +     if (!r)
> > > +             return -ENOMEM;

-- 
With Best Regards,
Andy Shevchenko

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