From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: Re: [PATCH net] ipv6: Fix cleanup ordering on inet6_init() error path Date: Sat, 13 Jan 2018 09:38:58 -0800 Message-ID: References: <20180109182116.olzb5rroeazq4ufv@xylophone.i.decadent.org.uk> <1515689336.12097.14.camel@codethink.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: Linux Kernel Network Developers , Andrey Konovalov To: Ben Hutchings Return-path: Received: from mail-pf0-f172.google.com ([209.85.192.172]:44032 "EHLO mail-pf0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751337AbeAMRjT (ORCPT ); Sat, 13 Jan 2018 12:39:19 -0500 Received: by mail-pf0-f172.google.com with SMTP id m26so6283202pfj.11 for ; Sat, 13 Jan 2018 09:39:19 -0800 (PST) In-Reply-To: <1515689336.12097.14.camel@codethink.co.uk> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Jan 11, 2018 at 8:48 AM, Ben Hutchings wrote: > On Wed, 2018-01-10 at 14:25 -0800, Cong Wang wrote: >> On Tue, Jan 9, 2018 at 10:21 AM, Ben Hutchings >> wrote: >> > Commit 15e668070a64 reordered the initialisation in inet6_init() to >> > fix a crash on an error path further down the call stack. It also >> > reordered cleanup on the error path in inet6_init(), but the result >> > is not the reverse of the initialisation order. This presumably >> > can result in a resource leak or crash in some error >> > cases. Reorder >> > cleanup again to fix this. >> >> Can you be specific on what resource we leak here? > > If icmpv6_init() fails, after ip6_mr_init(), then ip6_mr_cleanup() is > not called. > > Also, if ip6_mr_init() fails, we don't unregister inet6_net_ops. I > think that will result in a crash - immediately if ipv6 is a module, > otherwise when the next net namespace is created. Ah, I somehow misread the patch. It looks good. > >> Also, it looks like you not just revert the order changed in commit >> 15e668070a64, but also you move icmpv6_cleanup() even earlier. > > So should I add another Fixes: there? No, I think it is okay.