From: Peilin Ye <peilin.ye@xxxxxxxxxxxxx> Currently usbnet_disconnect() unanchors and frees all deferred URBs using usb_scuttle_anchored_urbs(), which does not free urb->context, causing a memory leak as reported by syzbot. Use a usb_get_from_anchor() while loop instead, similar to what we did in commit 19cfe912c37b ("Bluetooth: btusb: Fix memory leak in play_deferred"). Also free urb->sg. Reported-and-tested-by: syzbot+dcd3e13cf4472f2e0ba1@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 69ee472f2706 ("usbnet & cdc-ether: Autosuspend for online devices") Fixes: 638c5115a794 ("USBNET: support DMA SG") Signed-off-by: Peilin Ye <peilin.ye@xxxxxxxxxxxxx> --- Hi all, I think we may have similar issues at other usb_scuttle_anchored_urbs() call sites. Since urb->context is (void *), should we pass a "destructor" callback to usb_scuttle_anchored_urbs(), or replace this function with usb_get_from_anchor() loops like this patch does? Please advise, thanks! Peilin Ye drivers/net/usb/usbnet.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index fd399a8ed973..64a9a80b2309 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1598,6 +1598,7 @@ void usbnet_disconnect (struct usb_interface *intf) struct usbnet *dev; struct usb_device *xdev; struct net_device *net; + struct urb *urb; dev = usb_get_intfdata(intf); usb_set_intfdata(intf, NULL); @@ -1614,7 +1615,11 @@ void usbnet_disconnect (struct usb_interface *intf) net = dev->net; unregister_netdev (net); - usb_scuttle_anchored_urbs(&dev->deferred); + while ((urb = usb_get_from_anchor(&dev->deferred))) { + dev_kfree_skb(urb->context); + kfree(urb->sg); + usb_free_urb(urb); + } if (dev->driver_info->unbind) dev->driver_info->unbind(dev, intf); -- 2.20.1