Re: [patch] HID: logitech-hidpp: leaks and NULL dereferences

[Benjamin Tissoires <benjamin.tissoires@redhat.com>]

On Oct 31 2014 or thereabouts, Dan Carpenter wrote:
> Shift the allocation down a few lines to avoid a memory leak and also
> add a check for allocation failure.
> 
> Fixes: 2f31c5252910 ('HID: Introduce hidpp, a module to handle Logitech hid++ devices')
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> 

Ouch, I am ashamed of not having spot that :/

Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

Thanks Dan!
Benjamin

> diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
> index 361e97d..3cce995 100644
> --- a/drivers/hid/hid-logitech-hidpp.c
> +++ b/drivers/hid/hid-logitech-hidpp.c
> @@ -200,13 +200,15 @@ static int hidpp_send_fap_command_sync(struct hidpp_device *hidpp,
>  	u8 feat_index, u8 funcindex_clientid, u8 *params, int param_count,
>  	struct hidpp_report *response)
>  {
> -	struct hidpp_report *message = kzalloc(sizeof(struct hidpp_report),
> -			GFP_KERNEL);
> +	struct hidpp_report *message;
>  	int ret;
>  
>  	if (param_count > sizeof(message->fap.params))
>  		return -EINVAL;
>  
> +	message = kzalloc(sizeof(struct hidpp_report), GFP_KERNEL);
> +	if (!message)
> +		return -ENOMEM;
>  	message->report_id = REPORT_ID_HIDPP_LONG;
>  	message->fap.feature_index = feat_index;
>  	message->fap.funcindex_clientid = funcindex_clientid;
> @@ -221,8 +223,7 @@ static int hidpp_send_rap_command_sync(struct hidpp_device *hidpp_dev,
>  	u8 report_id, u8 sub_id, u8 reg_address, u8 *params, int param_count,
>  	struct hidpp_report *response)
>  {
> -	struct hidpp_report *message = kzalloc(sizeof(struct hidpp_report),
> -			GFP_KERNEL);
> +	struct hidpp_report *message;
>  	int ret;
>  
>  	if ((report_id != REPORT_ID_HIDPP_SHORT) &&
> @@ -232,6 +233,9 @@ static int hidpp_send_rap_command_sync(struct hidpp_device *hidpp_dev,
>  	if (param_count > sizeof(message->rap.params))
>  		return -EINVAL;
>  
> +	message = kzalloc(sizeof(struct hidpp_report), GFP_KERNEL);
> +	if (!message)
> +		return -ENOMEM;
>  	message->report_id = report_id;
>  	message->rap.sub_id = sub_id;
>  	message->rap.reg_address = reg_address;