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[209.132.180.67]) by mx.google.com with ESMTP id q3si10018157pgp.497.2019.07.01.11.22.27; Mon, 01 Jul 2019 11:22:41 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727084AbfGASEH (ORCPT + 99 others); Mon, 1 Jul 2019 14:04:07 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:46351 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727073AbfGASEG (ORCPT ); Mon, 1 Jul 2019 14:04:06 -0400 Received: by mail-lj1-f194.google.com with SMTP id v24so14140271ljg.13 for ; Mon, 01 Jul 2019 11:04:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=MjE0XPXG5+SObe6nqWe6b+FvEpLg7LFAzR1ek564VrQ=; b=G8XM9ImcUlDrCDRdpfKDGU5Js/hl7OBc6tjghE9Azel+TScycndsKqT9zVt74PiI6X 1Go0EyD8+T7USiVxOuwhOuA8upyY7YXfWZkMsc61UYT9ZGzDpZN7x1y1S7cLUWTF+tez EEg1KCvvyXTrW65q4aZV8jaw0GwbVvXWatNFwoDLFN1vyiYN/pQH7CBfEqaITtrnreJi 0e08BSm4mBnfb72//OXmrNKtFVP1/FKotkjNCxEwt5MnCDTej2iFD8k89cQzvhQOmuka d3OEHiwPtTyQ5Y8zGnndxnYm+JbiEp8y9taaJBx8AtMxMJlOoRt0ZOdrppvunyq/cCaD goDw== X-Gm-Message-State: APjAAAUkRNrd5+YvRRXTTZ5/5gn/V2IIW2jsbWcRoSgyLkfKZLZfjOu3 QbsmQE0I6W/yAz9HX+raIh/jSYXOVLFYUil+E0Pfnw== X-Received: by 2002:a2e:9117:: with SMTP id m23mr1503697ljg.134.1562004244498; Mon, 01 Jul 2019 11:04:04 -0700 (PDT) MIME-Version: 1.0 References: <20190628225533.GJ11506@sasha-vm> <1560226F-F2C0-440D-9C58-D664DE3C7322@appneta.com> <20190629074553.GA28708@kroah.com> <20190701175241.GB9081@kroah.com> In-Reply-To: <20190701175241.GB9081@kroah.com> From: Matteo Croce Date: Mon, 1 Jul 2019 20:03:28 +0200 Message-ID: Subject: Re: net: check before dereferencing netdev_ops during busy poll To: Josh Elsasser Cc: Greg Kroah-Hartman , Sasha Levin , stable@vger.kernel.org, netdev , LKML , David Miller Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 1, 2019 at 7:53 PM Greg Kroah-Hartman wrote: > > On Sat, Jun 29, 2019 at 09:39:39PM +0200, Matteo Croce wrote: > > On Sat, Jun 29, 2019 at 9:45 AM Greg Kroah-Hartman > > wrote: > > > > > > On Fri, Jun 28, 2019 at 07:03:01PM -0700, Josh Elsasser wrote: > > > > On Jun 28, 2019, at 3:55 PM, Sasha Levin wrote: > > > > > > > > > What's the upstream commit id? > > > > > > > > The commit wasn't needed upstream, as I only sent the original patch after > > > > 79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") had > > > > made the fix unnecessary in Linus' tree. > > > > > > > > May've gotten lost in the shuffle due to my poor Fixes tags. The patch in > > > > question applied only on top of the 4.9 stable release at the time, but the > > > > actual NPE had been around in some form since 3.11 / 0602129286705 ("net: add > > > > low latency socket poll"). > > > > > > Ok, can people then resend this and be very explicit as to why this is > > > needed only in a stable kernel tree and get reviews from people agreeing > > > that this really is the correct fix? > > > > > > thanks, > > > > > > greg k-h > > > > Hi Greg, > > > > I think that David alredy reviewed the patch here: > > > > https://lore.kernel.org/netdev/20180313.105115.682846171057663636.davem@davemloft.net/ > > > > Anyway, I tested the patch and it fixes the panic, at least on my > > iwlwifi card, so: > > > > Tested-by: Matteo Croce > > Ok, but what can I do with this? I need a real patch, in mail form, > that I can apply. Not a web link to an email archive. > > You have read the stable kernel rules, right? :) > > greg k-h Understood. Josh, as you are the original author, can you please resend it to -stable? Feel free to add this tag: Tested-by: Matteo Croce Regards, -- Matteo Croce per aspera ad upstream