[PATCH] staging: greybus: power_supply: fix prop-descriptor request size

[PATCH] staging: greybus: power_supply: fix prop-descriptor request size

[Johan Hovold]

Since moving the message buffers off the stack, the dynamically
allocated get-prop-descriptor request buffer is incorrectly sized due to
using the pointer rather than request-struct size when creating the
operation.

Fortunately, the pointer size is always larger than this one-byte
request, but this could still cause trouble on the remote end due to the
unexpected message size.

Fixes: 9d15134d067e ("greybus: power_supply: rework get descriptors")
Cc: stable <stable@vger.kernel.org>     # 4.9
Cc: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/staging/greybus/power_supply.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/greybus/power_supply.c b/drivers/staging/greybus/power_supply.c
index 0529e5628c24..ae5c0285a942 100644
--- a/drivers/staging/greybus/power_supply.c
+++ b/drivers/staging/greybus/power_supply.c
@@ -520,7 +520,7 @@ 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(*req), sizeof(*resp) + props_count *
 				 sizeof(struct gb_power_supply_props_desc),
 				 GFP_KERNEL);
 	if (!op)
-- 
2.21.0

Re: [PATCH] staging: greybus: power_supply: fix prop-descriptor request size

[Rui Miguel Silva]

Hi Johan,
Thanks for the patch.

On Thu 04 Apr 2019 at 07:53, Johan Hovold wrote:
> Since moving the message buffers off the stack, the dynamically
> allocated get-prop-descriptor request buffer is incorrectly 
> sized due to
> using the pointer rather than request-struct size when creating 
> the
> operation.
>
> Fortunately, the pointer size is always larger than this 
> one-byte
> request, but this could still cause trouble on the remote end 
> due to the
> unexpected message size.
>
> Fixes: 9d15134d067e ("greybus: power_supply: rework get 
> descriptors")
> Cc: stable <stable@vger.kernel.org>     # 4.9
> Cc: Rui Miguel Silva <rui.silva@linaro.org>
> Signed-off-by: Johan Hovold <johan@kernel.org>

Nice catch. LGTM.

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

---
Cheers,
	Rui


> ---
>  drivers/staging/greybus/power_supply.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/greybus/power_supply.c 
> b/drivers/staging/greybus/power_supply.c
> index 0529e5628c24..ae5c0285a942 100644
> --- a/drivers/staging/greybus/power_supply.c
> +++ b/drivers/staging/greybus/power_supply.c
> @@ -520,7 +520,7 @@ 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(*req), sizeof(*resp) + 
> props_count *
>  				 sizeof(struct 
>  gb_power_supply_props_desc),
>  				 GFP_KERNEL);
>  	if (!op)