Re: [PATCH] scsi: aacraid: fix leak of data from stack back to userspace

[walter harms <wharms@bfs.de>]

Am 15.05.2017 16:56, schrieb Colin King:
> From: Colin Ian King <colin.king@canonical.com>
> 
> The fields sense_data_size and sense_data are unitialized garbage from
> the stack and are being copied back to userspace.  Fix this leak of
> stack information by ensuring they are zero'd.
> 
> Detected by CoverityScan, CID#1435473 ("Uninitialized scalar variable")
> 
> Fixes: 423400e64d377 ("scsi: aacraid: Include HBA direct interface")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
>  drivers/scsi/aacraid/commctrl.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/scsi/aacraid/commctrl.c b/drivers/scsi/aacraid/commctrl.c
> index 106b9332f718..6bb6ed48e31d 100644
> --- a/drivers/scsi/aacraid/commctrl.c
> +++ b/drivers/scsi/aacraid/commctrl.c
> @@ -955,6 +955,8 @@ static int aac_send_raw_srb(struct aac_dev* dev, void __user * arg)
>  			reply.srb_status = SRB_STATUS_SUCCESS;
>  			reply.scsi_status = 0;
>  			reply.data_xfer_length = byte_count;
> +			reply.sense_data_size = 0;
> +			memset(reply.sense_data, 0, AAC_SENSE_BUFFERSIZE);
>  		} else {
>  			reply.srb_status = err->service_response;
>  			reply.scsi_status = err->status;


an other idea would be initialize the reply with zero:
struct aac_srb_reply reply={0};

maybe that is more future proof but i have no idea about the speed penalty.

just my 2 cents,
 wh