From: Takashi Iwai <tiwai@xxxxxxx>
commit c49206786ee252f28b7d4d155d1fff96f145a05d upstream.
dvb_usb_device_init() copies the properties to the own data, so that
the callers can release the original properties later (as done in the
commit 299c7007e936 ("media: dw2102: Fix memleak on sequence of
probes")). However, it also stores dev->desc pointer that is a
reference to the original properties data. Since dev->desc is
referred later, it may result in use-after-free, in the worst case,
leading to a kernel Oops as reported.
This patch addresses the problem by allocating and copying the
properties at first, then get the desc from the copied properties.
Reported-and-tested-by: Stefan Seyfried <seife+kernel@xxxxxxxxxxxxxx>
BugLink: http://bugzilla.opensuse.org/show_bug.cgi?id=1181104
Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sean Young <sean@xxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/media/usb/dvb-usb/dvb-usb-init.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)
--- a/drivers/media/usb/dvb-usb/dvb-usb-init.c
+++ b/drivers/media/usb/dvb-usb/dvb-usb-init.c
@@ -267,27 +267,30 @@ int dvb_usb_device_init(struct usb_inter
if (du != NULL)
*du = NULL;
- if ((desc = dvb_usb_find_device(udev, props, &cold)) == NULL) {
+ d = kzalloc(sizeof(*d), GFP_KERNEL);
+ if (!d) {
+ err("no memory for 'struct dvb_usb_device'");
+ return -ENOMEM;
+ }
+
+ memcpy(&d->props, props, sizeof(struct dvb_usb_device_properties));
+
+ desc = dvb_usb_find_device(udev, &d->props, &cold);
+ if (!desc) {
deb_err("something went very wrong, device was not found in current device list - let's see what comes next.\n");
- return -ENODEV;
+ ret = -ENODEV;
+ goto error;
}
if (cold) {
info("found a '%s' in cold state, will try to load a firmware", desc->name);
ret = dvb_usb_download_firmware(udev, props);
if (!props->no_reconnect || ret != 0)
- return ret;
+ goto error;
}
info("found a '%s' in warm state.", desc->name);
- d = kzalloc(sizeof(struct dvb_usb_device), GFP_KERNEL);
- if (d == NULL) {
- err("no memory for 'struct dvb_usb_device'");
- return -ENOMEM;
- }
-
d->udev = udev;
- memcpy(&d->props, props, sizeof(struct dvb_usb_device_properties));
d->desc = desc;
d->owner = owner;
