[PATCH v2] staging: greybus: power_supply: use struct_size() helper

[PATCH v2] staging: greybus: power_supply: use struct_size() helper

[Gustavo A. R. Silva]

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.

So, replace code of the following form:

sizeof(*resp) + props_count * sizeof(struct gb_power_supply_props_desc)

with:

struct_size(resp, props, props_count)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
Changes in v2:
 - Rebase on top of 47830c1127ef ("staging: greybus: power_supply: fix prop-descriptor request size")

 drivers/staging/greybus/power_supply.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/greybus/power_supply.c b/drivers/staging/greybus/power_supply.c
index ae5c0285a942..34b40a409ea3 100644
--- a/drivers/staging/greybus/power_supply.c
+++ b/drivers/staging/greybus/power_supply.c
@@ -520,8 +520,8 @@ static int gb_power_supply_prop_descriptors_get(struct gb_power_supply *gbpsy)
 
 	op = gb_operation_create(connection,
 				 GB_POWER_SUPPLY_TYPE_GET_PROP_DESCRIPTORS,
-				 sizeof(*req), sizeof(*resp) + props_count *
-				 sizeof(struct gb_power_supply_props_desc),
+				 sizeof(*req),
+				 struct_size(resp, props, props_count),
 				 GFP_KERNEL);
 	if (!op)
 		return -ENOMEM;
-- 
2.21.0

Re: [PATCH v2] staging: greybus: power_supply: use struct_size() helper

[Johan Hovold]

On Wed, Apr 17, 2019 at 01:44:40PM -0500, Gustavo A. R. Silva wrote:
> Make use of the struct_size() helper instead of an open-coded version
> in order to avoid any potential type mistakes, in particular in the
> context in which this code is being used.
> 
> So, replace code of the following form:
> 
> sizeof(*resp) + props_count * sizeof(struct gb_power_supply_props_desc)
> 
> with:
> 
> struct_size(resp, props, props_count)
> 
> This code was detected with the help of Coccinelle.
> 
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
> ---
> Changes in v2:
>  - Rebase on top of 47830c1127ef ("staging: greybus: power_supply: fix prop-descriptor request size")

Thanks for rebasing.

Reviewed-by: Johan Hovold <johan@kernel.org>

Johan

Re: [PATCH v2] staging: greybus: power_supply: use struct_size() helper

[Rui Miguel Silva]

Oi Gustavo,
Thanks for the patch, and the rebasing.

On Wed 17 Apr 2019 at 19:44, Gustavo A. R. Silva wrote:
> Make use of the struct_size() helper instead of an open-coded 
> version
> in order to avoid any potential type mistakes, in particular in 
> the
> context in which this code is being used.
>
> So, replace code of the following form:
>
> sizeof(*resp) + props_count * sizeof(struct 
> gb_power_supply_props_desc)
>
> with:
>
> struct_size(resp, props, props_count)
>
> This code was detected with the help of Coccinelle.
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>

---
Cheers,
	Rui


> ---
> Changes in v2:
>  - Rebase on top of 47830c1127ef ("staging: greybus: 
>  power_supply: fix prop-descriptor request size")
>
>  drivers/staging/greybus/power_supply.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/greybus/power_supply.c 
> b/drivers/staging/greybus/power_supply.c
> index ae5c0285a942..34b40a409ea3 100644
> --- a/drivers/staging/greybus/power_supply.c
> +++ b/drivers/staging/greybus/power_supply.c
> @@ -520,8 +520,8 @@ static int 
> gb_power_supply_prop_descriptors_get(struct gb_power_supply 
> *gbpsy)
>  
>  	op = gb_operation_create(connection,
>  				 GB_POWER_SUPPLY_TYPE_GET_PROP_DESCRIPTORS,
> -				 sizeof(*req), sizeof(*resp) + 
> props_count *
> -				 sizeof(struct 
> gb_power_supply_props_desc),
> +				 sizeof(*req),
> +				 struct_size(resp, props, 
> props_count),
>  				 GFP_KERNEL);
>  	if (!op)
>  		return -ENOMEM;

Re: [PATCH v2] staging: greybus: power_supply: use struct_size() helper

[Gustavo A. R. Silva]

On 4/18/19 1:27 AM, Johan Hovold wrote:
> On Wed, Apr 17, 2019 at 01:44:40PM -0500, Gustavo A. R. Silva wrote:
>> Make use of the struct_size() helper instead of an open-coded version
>> in order to avoid any potential type mistakes, in particular in the
>> context in which this code is being used.
>>
>> So, replace code of the following form:
>>
>> sizeof(*resp) + props_count * sizeof(struct gb_power_supply_props_desc)
>>
>> with:
>>
>> struct_size(resp, props, props_count)
>>
>> This code was detected with the help of Coccinelle.
>>
>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
>> ---
>> Changes in v2:
>>  - Rebase on top of 47830c1127ef ("staging: greybus: power_supply: fix prop-descriptor request size")
> 
> Thanks for rebasing.
> 

Glad to help. :)

> Reviewed-by: Johan Hovold <johan@kernel.org>
> 

Thanks
--
Gustavo