net: caif: fix memory leak in cfusbl_device_notify

BugLink: https://bugs.launchpad.net/bugs/1933691
commit 7f5d86669fa4d485523ddb1d212e0a2d90bd62bb upstream.

In case of caif_enroll_dev() fail, allocated
link_support won't be assigned to the corresponding
structure. So simply free allocated pointer in case
of error.

Fixes: 7ad65bf68d70 ("caif: Add support for CAIF over CDC NCM USB interface")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/net/caif/caif_usb.c b/net/caif/caif_usb.c
index a0116b9503d9da9a2733f0b7f8aae4f1b3ceeda9..b02e1292f7f1929b535338e6197d26d6f5f475f3 100644 (file)
--- a/net/caif/caif_usb.c
+++ b/net/caif/caif_usb.c
@@ -115,6 +115,11 @@ static struct cflayer *cfusbl_create(int phyid, u8 ethaddr[ETH_ALEN],
        return (struct cflayer *) this;
 }
 
+static void cfusbl_release(struct cflayer *layer)
+{
+       kfree(layer);
+}
+
 static struct packet_type caif_usb_type __read_mostly = {
        .type = cpu_to_be16(ETH_P_802_EX1),
 };
@@ -127,6 +132,7 @@ static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
        struct cflayer *layer, *link_support;
        struct usbnet *usbnet;
        struct usb_device *usbdev;
+       int res;
 
        /* Check whether we have a NCM device, and find its VID/PID. */
        if (!(dev->dev.parent && dev->dev.parent->driver &&
@@ -169,8 +175,11 @@ static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
        if (dev->num_tx_queues > 1)
                pr_warn("USB device uses more than one tx queue\n");
 
-       caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN,
+       res = caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN,
                        &layer, &caif_usb_type.func);
+       if (res)
+               goto err;
+
        if (!pack_added)
                dev_add_pack(&caif_usb_type);
        pack_added = true;
@@ -178,6 +187,9 @@ static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
        strlcpy(layer->name, dev->name, sizeof(layer->name));
 
        return 0;
+err:
+       cfusbl_release(link_support);
+       return res;
 }
 
 static struct notifier_block caif_device_notifier = {