lkml.org 
[lkml]   [2018]   [Aug]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] memory: atmel-ebi: Use struct_size() in devm_kzalloc()
On Thu, Aug 23, 2018 at 6:07 PM, Gustavo A. R. Silva
<gustavo@embeddedor.com> wrote:
> One of the more common cases of allocation size calculations is finding
> the size of a structure that has a zero-sized array at the end, along
> with memory for some number of elements for that array. For example:
>
> struct foo {
> int stuff;
> void *entry[];
> };
>
> instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
>
> Instead of leaving these open-coded and prone to type mistakes, we can
> now use the new struct_size() helper:
>
> instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL);
>
> This issue was detected with the help of Coccinelle.
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

-Kees

> ---
> drivers/memory/atmel-ebi.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/memory/atmel-ebi.c b/drivers/memory/atmel-ebi.c
> index b907865..c3748b4 100644
> --- a/drivers/memory/atmel-ebi.c
> +++ b/drivers/memory/atmel-ebi.c
> @@ -327,8 +327,7 @@ static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
> return -EINVAL;
> }
>
> - ebid = devm_kzalloc(ebi->dev,
> - sizeof(*ebid) + (numcs * sizeof(*ebid->configs)),
> + ebid = devm_kzalloc(ebi->dev, struct_size(ebid, configs, numcs),
> GFP_KERNEL);
> if (!ebid)
> return -ENOMEM;
> --
> 2.7.4
>



--
Kees Cook
Pixel Security

\
 
 \ /
  Last update: 2018-08-24 04:57    [W:0.061 / U:3.232 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site