From: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
commit a47686636d84eaec5c9c6e84bd5f96bed34d526d upstream.
Most Siano devices require an alignment for the response.
Changeset f3be52b0056a ("media: usb: siano: Fix general protection fault in smsusb")
changed the logic with gets such aligment, but it now produces a
sparce warning:
drivers/media/usb/siano/smsusb.c: In function 'smsusb_init_device':
drivers/media/usb/siano/smsusb.c:447:37: warning: 'in_maxp' may be used uninitialized in this function [-Wmaybe-uninitialized]
447 | dev->response_alignment = in_maxp - sizeof(struct sms_msg_hdr);
| ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
The sparse message itself is bogus, but a broken (or fake) USB
eeprom could produce a negative value for response_alignment.
So, change the code in order to check if the result is not
negative.
Fixes: 31e0456de5be ("media: usb: siano: Fix general protection fault in smsusb")
CC: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/media/usb/siano/smsusb.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/media/usb/siano/smsusb.c
+++ b/drivers/media/usb/siano/smsusb.c
@@ -402,7 +402,7 @@ static int smsusb_init_device(struct usb
struct smsusb_device_t *dev;
void *mdev;
int i, rc;
- int in_maxp = 0;
+ int align = 0;
/* create device object */
dev = kzalloc(sizeof(struct smsusb_device_t), GFP_KERNEL);
@@ -420,14 +420,14 @@ static int smsusb_init_device(struct usb
if (desc->bEndpointAddress & USB_DIR_IN) {
dev->in_ep = desc->bEndpointAddress;
- in_maxp = usb_endpoint_maxp(desc);
+ align = usb_endpoint_maxp(desc) - sizeof(struct sms_msg_hdr);
} else {
dev->out_ep = desc->bEndpointAddress;
}
}
pr_debug("in_ep = %02x, out_ep = %02x\n", dev->in_ep, dev->out_ep);
- if (!dev->in_ep || !dev->out_ep) { /* Missing endpoints? */
+ if (!dev->in_ep || !dev->out_ep || align < 0) { /* Missing endpoints? */
smsusb_term_device(intf);
return -ENODEV;
}
@@ -446,7 +446,7 @@ static int smsusb_init_device(struct usb
/* fall-thru */
default:
dev->buffer_size = USB2_BUFFER_SIZE;
- dev->response_alignment = in_maxp - sizeof(struct sms_msg_hdr);
+ dev->response_alignment = align;
params.flags |= SMS_DEVICE_FAMILY2;
break;
