From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [PATCH net] net: sched: fix NULL pointer dereference when action calls some targets Date: Thu, 17 Aug 2017 12:02:20 +0200 Message-ID: <20170817100220.GC6928@salvia> References: <0fa9a53725dd661571461cf283ec88cf15f4b139.1501932907.git.lucien.xin@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Cong Wang , network dev , David Miller , netfilter-devel@vger.kernel.org, Jamal Hadi Salim To: Xin Long Return-path: Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org On Wed, Aug 16, 2017 at 08:39:44PM +1200, Xin Long wrote: > On Wed, Aug 9, 2017 at 7:33 AM, Cong Wang wrote: > > On Mon, Aug 7, 2017 at 7:33 PM, Xin Long wrote: > >> On Tue, Aug 8, 2017 at 9:15 AM, Cong Wang wrote: > >>> This looks like a completely API burden? > >> netfilter xt targets are not really compatible with netsched action. > >> I've got to say, the patch is just a way to make checkentry return > >> false and avoid panic. like [1] said > > > > I don't doubt you fix a crash, I am thinking if we can > > "fix" the API instead of fixing the caller. > Hi, Cong, > > For now, I don't think it's possible to change APIs or some of their targets > for the panic caused by action xt calling. > > The common way should be fixed in net_sched side. > > Given that the issue is very easy to triggered, > let's wait for netfilter's replies for another few days, > otherwise I will repost the fix, agree ? Please, post the workaround so the kernel doesn't crash anymore. This is going to be very hard to fix, it's broken since the very beginning... Thanks!