netdev - RE: [Patch net v2] tipc: fix a null pointer deref on error path

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <AM4PR07MB17140DAC84D397BB05E84E449A3C0@AM4PR07MB1714.eurprd07.prod.outlook.com>
Date:   Mon, 4 Dec 2017 20:32:55 +0000
From:   Jon Maloy <jon.maloy@...csson.com>
To:     Jon Maloy <jon.maloy@...csson.com>,
        Cong Wang <xiyou.wangcong@...il.com>,
        David Miller <davem@...emloft.net>
CC:     Linux Kernel Network Developers <netdev@...r.kernel.org>,
        "tipc-discussion@...ts.sourceforge.net" 
        <tipc-discussion@...ts.sourceforge.net>,
        Ying Xue <ying.xue@...driver.com>
Subject: RE: [Patch net v2] tipc: fix a null pointer deref on error path



> -----Original Message-----
> From: netdev-owner@...r.kernel.org [mailto:netdev-
> owner@...r.kernel.org] On Behalf Of Jon Maloy
> Sent: Monday, December 04, 2017 14:50
> To: Cong Wang <xiyou.wangcong@...il.com>; David Miller
> <davem@...emloft.net>
> Cc: Linux Kernel Network Developers <netdev@...r.kernel.org>; tipc-
> discussion@...ts.sourceforge.net; Ying Xue <ying.xue@...driver.com>
> Subject: RE: [Patch net v2] tipc: fix a null pointer deref on error path
> 
> 
> 
> > -----Original Message-----
> > From: Cong Wang [mailto:xiyou.wangcong@...il.com]
> > Sent: Monday, December 04, 2017 14:41
> > To: David Miller <davem@...emloft.net>
> > Cc: Linux Kernel Network Developers <netdev@...r.kernel.org>; tipc-
> > discussion@...ts.sourceforge.net; Jon Maloy <jon.maloy@...csson.com>;
> > Ying Xue <ying.xue@...driver.com>
> > Subject: Re: [Patch net v2] tipc: fix a null pointer deref on error
> > path
> >
> > On Mon, Dec 4, 2017 at 11:23 AM, Cong Wang
> <xiyou.wangcong@...il.com>
> > wrote:
> > > On Mon, Dec 4, 2017 at 10:57 AM, David Miller <davem@...emloft.net>
> > wrote:
> > >>
> > >> It looks like tipc_accept_from_sock() has a similar problem?  The
> > >> tipc_close_conn() will get invoked indirectly from the
> > >> sock_release() path right?
> > >
> > > Not sure, the sock_release() in tipc_accept_from_sock() is for
> > > kernel_accept(), not for tipc_alloc_conn(). Or maybe it is hiding
> > > deep in the call chain that I miss?
> >
> > I see:
> >
> > tipc_release() ->  tipc_sk_leave() -> tipc_group_delete()
> > -> tipc_topsrv_kern_unsubscr() -> tipc_close_conn()
> >
> > Seems on this path we do need to skip NULL too.
> 
> You are right. The right solution is to just call conn_put() twice here.
> I already have a patch ready for this, but it is part of a series that needs more
> review.
> I should probably post it separately...

Well, calling conn_put() twice was ok in my series, but in the current upstream version it is not enough.
I will find a different short term solution.

///jon

> 
> ///jon