From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 709CEC433FE for ; Mon, 21 Feb 2022 12:29:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357964AbiBUM3z (ORCPT ); Mon, 21 Feb 2022 07:29:55 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:41896 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357937AbiBUM3u (ORCPT ); Mon, 21 Feb 2022 07:29:50 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28DBE13E30; Mon, 21 Feb 2022 04:29:27 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B1A11612F4; Mon, 21 Feb 2022 12:29:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BD119C340E9; Mon, 21 Feb 2022 12:29:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645446566; bh=OmaFrsn4s+m3QVaKvKOf/kobmLt37ekHUhLTfYwN+aY=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=pJmp+/omTpvcZWxpevQ0CyeM0kuRuVZmPXc9F0Bqhe8LOlZV69V0uAx7KZ1+NH2S8 17hNJgYkXykg698Q8cAmm14xQj7l94k9+uri99h2NR4BzW8hUA3K2wsUvJMpeM2aLI ikfBkhYFP1wB9RHq48Ccx4M0vjuaTInxavS6weLNHmxxoXW+l6BufjbINWTLVtycap KBzwsBCNcRna0p2HoTp85M/+hhu//31c4Wrw3rxqnCk2D0ruWf4jN5ZI/US+6Le6hm aDFFnr3iAR+K7uOyLSFkdDTvtUnyhN8ajPtzpIQyQNM+j+T4+pzrseQn1lMeJlIEjA GpG8pLJjgoWQQ== From: Kalle Valo To: Thorsten Leemhuis Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Stefan Agner , Wolfgang Walter , Jason Self , Dominik Behr , Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= , Johannes Berg Subject: Re: [PATCH 5.16 077/227] iwlwifi: fix use-after-free References: <20220221084934.836145070@linuxfoundation.org> <20220221084937.429986092@linuxfoundation.org> Date: Mon, 21 Feb 2022 14:29:19 +0200 In-Reply-To: (Thorsten Leemhuis's message of "Mon, 21 Feb 2022 13:00:40 +0100") Message-ID: <87h78swggw.fsf@kernel.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thorsten Leemhuis writes: > Hi, this is your Linux kernel regression tracker. > > On 21.02.22 09:48, Greg Kroah-Hartman wrote: >> From: Johannes Berg >>=20 >> commit bea2662e7818e15d7607d17d57912ac984275d94 upstream. >>=20 >> If no firmware was present at all (or, presumably, all of the >> firmware files failed to parse), we end up unbinding by calling >> device_release_driver(), which calls remove(), which then in >> iwlwifi calls iwl_drv_stop(), freeing the 'drv' struct. However >> the new code I added will still erroneously access it after it >> was freed. >>=20 >> Set 'failure=3Dfalse' in this case to avoid the access, all data >> was already freed anyway. >>=20 >> Cc: stable@vger.kernel.org >> Reported-by: Stefan Agner >> Reported-by: Wolfgang Walter >> Reported-by: Jason Self >> Reported-by: Dominik Behr >> Reported-by: Marek Marczykowski-G=C3=B3recki >> Fixes: ab07506b0454 ("iwlwifi: fix leaks/bad data after failed firmware = load") >> Signed-off-by: Johannes Berg >> Signed-off-by: Kalle Valo >> Link: >> https://lore.kernel.org/r/20220208114728.e6b514cf4c85.Iffb575ca2a623d785= 9b542c33b2a507d01554251@changeid >> Signed-off-by: Greg Kroah-Hartman > > Great to see that you quickly picked up this patch. Once the new stable > and longterm releases are out on Wednesday, it will fix a regression > that made it into many stable and longterm kernels nearly four weeks > earlier. I tracked the issue, which made me we wonder: should I have > done something differently in this case to get the regression resolved > more quickly? Should I maybe have suggested to remove the culprit > temporarily until the fix was merged to mainline? > > For context, this is the story of the regression afaics: the change > ab07506b0454 ("iwlwifi: fix leaks/bad data after failed firmware load") > was merged for 5.17-rc1 (released on 2022-01-23). Shortly after it was > backported to several stable/longterm series with new versions released > on 2022-01-27. It triggered a general protection fault, if the proper > firmware file was missing. Afaics at least five people reported the > problem between 2022-02-01 and 2022-02-11 for at least 5.10.y, 5.15.y > and 5.16.y (some of those reports were on the stable list), which shows > that such a setup is not that unusual. A fix was posted on 2022-02-08 > and approved and committed by a maintainer on 2022-02-10. It was then > merged to mainline on 2022-02-17 (I hope we can find ways to reduce such > particular timeframes in the future, but that's a different story). >From mainline point of view there is not really any easy way to make this faster. There are multiple trees involved and pull requests always take time (we cannot submit a pull request for every commit sepately), --=20 https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatc= hes