From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: Possible double-free in the usbnet driver Date: Mon, 07 Mar 2016 14:11:00 -0500 (EST) Message-ID: <20160307.141100.1511700720120062677.davem@davemloft.net> References: <1457193090.8935.7.camel@suse.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: bjorn-yOkvZcmFvRU@public.gmane.org, oneukum-IBi9RG/b67k@public.gmane.org, andreyknvl-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, dvyukov-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, glider-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, kcc-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org Return-path: In-Reply-To: Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org =46rom: Linus Torvalds Date: Mon, 7 Mar 2016 10:13:09 -0800 > On Sat, Mar 5, 2016 at 11:53 AM, Bj=F8rn Mork wrote: >> >> >> Definitely. The patch is so obviously correct that we can only wond= er how it was possible to miss it it the first place :) >> >> Will take a look to see if we could do a better job cleaning up in o= ther places. >=20 > What should I do for 4.5? Will there be a pull request for this, or > should I just commit my cdc_ncm_bind() patch directly? Yes I plan to send you a pull request today with Oliver's fix. Assuming this is what you guys are referring to: commit 1666984c8625b3db19a9abc298931d35ab7bc64b Author: Oliver Neukum Date: Mon Mar 7 11:31:10 2016 +0100 usbnet: cleanup after bind() in probe() =20 In case bind() works, but a later error forces bailing in probe() in error cases work and a timer may be scheduled. They must be killed. This fixes an error case related to the double free reported in http://www.spinics.net/lists/netdev/msg367669.html and needs to go on top of Linus' fix to cdc-ncm. =20 Signed-off-by: Oliver Neukum Signed-off-by: David S. Miller diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 0b0ba7e..1079812 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1769,6 +1769,13 @@ out3: if (info->unbind) info->unbind (dev, udev); out1: + /* subdrivers must undo all they did in bind() if they + * fail it, but we may fail later and a deferred kevent + * may trigger an error resubmitting itself and, worse, + * schedule a timer. So we kill it all just in case. + */ + cancel_work_sync(&dev->kevent); + del_timer_sync(&dev->delay); free_netdev(net); out: return status; -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html