From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH net] vrf: fix double free and memory corruption on register_netdevice failure Date: Sat, 21 Nov 2015 15:55:36 -0700 Message-ID: <5650F668.8020502@cumulusnetworks.com> References: <1448131579-20525-1-git-send-email-razor@blackwall.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: shm@cumulusnetworks.com, davem@davemloft.net, Nikolay Aleksandrov To: Nikolay Aleksandrov , netdev@vger.kernel.org Return-path: Received: from mail-ig0-f173.google.com ([209.85.213.173]:35987 "EHLO mail-ig0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750891AbbKUWzk (ORCPT ); Sat, 21 Nov 2015 17:55:40 -0500 Received: by igcph11 with SMTP id ph11so31913968igc.1 for ; Sat, 21 Nov 2015 14:55:39 -0800 (PST) In-Reply-To: <1448131579-20525-1-git-send-email-razor@blackwall.org> Sender: netdev-owner@vger.kernel.org List-ID: On 11/21/15 11:46 AM, Nikolay Aleksandrov wrote: > From: Nikolay Aleksandrov > > When vrf's ->newlink is called, if register_netdevice() fails then it > does free_netdev(), but that's also done by rtnl_newlink() so a second > free happens and memory gets corrupted, to reproduce execute the > following line a couple of times (1 - 5 usually is enough): > $ for i in `seq 1 5`; do ip link add vrf: type vrf table 1; done; > This works because we fail in register_netdevice() because of the wrong > name "vrf:". Acked-by: David Ahern Thanks, Nik.