staging: ozwpan: prevent a couple of underflows

The underflow in OZ_DATA_F_ISOC_FIXED seems not harmful, but this patch
is a clean up and makes my static checker a bit happier.

The underflow in OZ_VENDOR_CLASS_RSP seems like it could result in
memory corruption.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Dan Carpenter 2015-06-02 15:20:25 +03:00 committed by Greg Kroah-Hartman
parent c938699ebb
commit ba470f7c0e
1 changed files with 10 additions and 1 deletions

View File

@ -342,12 +342,16 @@ static void oz_usb_handle_ep_data(struct oz_usb_ctx *usb_ctx,
case OZ_DATA_F_ISOC_FIXED: {
struct oz_isoc_fixed *body =
(struct oz_isoc_fixed *)data_hdr;
int data_len = len-sizeof(struct oz_isoc_fixed)+1;
int data_len;
int unit_size = body->unit_size;
u8 *data = body->data;
int count;
int i;
if (len < sizeof(struct oz_isoc_fixed) - 1)
break;
data_len = len - (sizeof(struct oz_isoc_fixed) - 1);
if (!unit_size)
break;
count = data_len/unit_size;
@ -427,6 +431,11 @@ void oz_usb_rx(struct oz_pd *pd, struct oz_elt *elt)
case OZ_VENDOR_CLASS_RSP: {
struct oz_vendor_class_rsp *body =
(struct oz_vendor_class_rsp *)usb_hdr;
if (elt->length <
sizeof(struct oz_vendor_class_rsp) - 1)
break;
oz_hcd_control_cnf(usb_ctx->hport, body->req_id,
body->rcode, body->data, elt->length-
sizeof(struct oz_vendor_class_rsp)+1);