udlfb: fix some inconsistent NULL checking

In the current kernel, then kzalloc() can't fail for small allocations,
but if it did fail then we would have a NULL dereference in the error
handling.  Also in dlfb_usb_disconnect() if "info" were NULL then it
would cause an Oops inside the unregister_framebuffer() function but it
can't be NULL so let's remove that check.

Fixes: 68a958a915 ("udlfb: handle unplug properly")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Wen Yang <wen.yang99@zte.com.cn>
[b.zolnierkie: added "Fixes:" tag]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
This commit is contained in:
Dan Carpenter 2018-12-20 19:13:07 +01:00 committed by Bartlomiej Zolnierkiewicz
parent 31d1b77102
commit c143a559b0

View File

@ -1598,7 +1598,7 @@ static int dlfb_usb_probe(struct usb_interface *intf,
dlfb = kzalloc(sizeof(*dlfb), GFP_KERNEL);
if (!dlfb) {
dev_err(&intf->dev, "%s: failed to allocate dlfb\n", __func__);
goto error;
return -ENOMEM;
}
INIT_LIST_HEAD(&dlfb->deferred_free);
@ -1703,7 +1703,7 @@ static int dlfb_usb_probe(struct usb_interface *intf,
error:
if (dlfb->info) {
dlfb_ops_destroy(dlfb->info);
} else if (dlfb) {
} else {
usb_put_dev(dlfb->udev);
kfree(dlfb);
}
@ -1730,12 +1730,10 @@ static void dlfb_usb_disconnect(struct usb_interface *intf)
/* this function will wait for all in-flight urbs to complete */
dlfb_free_urb_list(dlfb);
if (info) {
/* remove udlfb's sysfs interfaces */
for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
device_remove_file(info->dev, &fb_device_attrs[i]);
device_remove_bin_file(info->dev, &edid_attr);
}
/* remove udlfb's sysfs interfaces */
for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)
device_remove_file(info->dev, &fb_device_attrs[i]);
device_remove_bin_file(info->dev, &edid_attr);
unregister_framebuffer(info);
}