linux-kernel - RE: [PATCH] qed: fix possible unpaired spin_{un}lock_bh in _qed_mcp_cmd_and

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] [day] [month] [year] [list]

Message-ID: <AM6PR08MB43767F0DA3616FC513F289C2F7E29@AM6PR08MB4376.eurprd08.prod.outlook.com>
Date:   Tue, 20 Jul 2021 09:28:34 +0000
From:   Justin He <Justin.He@....com>
To:     Jakub Kicinski <kuba@...nel.org>
CC:     Prabhakar Kushwaha <prabhakar.pkin@...il.com>,
        "David S. Miller" <davem@...emloft.net>,
        Ariel Elior <aelior@...vell.com>,
        "GR-everest-linux-l2@...vell.com" <GR-everest-linux-l2@...vell.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        nd <nd@....com>, Shai Malin <malin1024@...il.com>,
        Shai Malin <smalin@...vell.com>,
        Prabhakar Kushwaha <pkushwaha@...vell.com>, nd <nd@....com>
Subject: RE: [PATCH] qed: fix possible unpaired spin_{un}lock_bh in
 _qed_mcp_cmd_and_union()



> -----Original Message-----
> From: Jakub Kicinski <kuba@...nel.org>
> Sent: Tuesday, July 20, 2021 5:06 PM
> To: Justin He <Justin.He@....com>
> Cc: Prabhakar Kushwaha <prabhakar.pkin@...il.com>; David S. Miller
> <davem@...emloft.net>; Ariel Elior <aelior@...vell.com>; GR-everest-linux-
> l2@...vell.com; netdev@...r.kernel.org; Linux Kernel Mailing List <linux-
> kernel@...r.kernel.org>; nd <nd@....com>; Shai Malin <malin1024@...il.com>;
> Shai Malin <smalin@...vell.com>; Prabhakar Kushwaha <pkushwaha@...vell.com>
> Subject: Re: [PATCH] qed: fix possible unpaired spin_{un}lock_bh in
> _qed_mcp_cmd_and_union()
> 
> On Tue, 20 Jul 2021 02:02:26 +0000, Justin He wrote:
> > > > For instance:
> > > > _qed_mcp_cmd_and_union()
> > > >   In while loop
> > > >     spin_lock_bh()
> > > >     qed_mcp_has_pending_cmd() (assume false), will break the loop
> > >
> > > I agree till here.
> > >
> > > >   if (cnt >= max_retries) {
> > > > ...
> > > >     return -EAGAIN; <-- here returns -EAGAIN without invoking bh
> unlock
> > > >   }
> > > >
> > >
> > > Because of break, cnt has not been increased.
> > >    - cnt is still less than max_retries.
> > >   - if (cnt >= max_retries) will not be *true*, leading to
> spin_unlock_bh().
> > > Hence pairing completed.
> >
> > Sorry, indeed. Let me check other possibilities.
> > @David S. Miller Sorry for the inconvenience, could you please revert it
> > in netdev tree?
> 
> Please submit a revert patch with the conclusions from the discussion
> included in the commit message.
Okay，will do that
Thanks for the reminder

--
Cheers,
Justin (Jia He)