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 X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D61EBC43381 for ; Fri, 15 Feb 2019 07:00:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9C6A521A80 for ; Fri, 15 Feb 2019 07:00:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550214044; bh=QvuU6OQQXmO+iO2uyK/vGfsXfea1cbNeulcpEwUm2vg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Tbx9dL7AlJ05WZDFZdXhNvTEmlstG4O//4CSu9VwtUvMyg8IEF1VQNeoZuJowFY+J M6SFW4yspP1b7sj+tX4Y3JzEJcjRi/IqnOefA/GZ/HLxiTCJo6cAVGlroH04iSMtlb R7Kqhs1aBTV79MzkG6i9iDKmEmSWTdxUsmVyMBI0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389025AbfBOHAi (ORCPT ); Fri, 15 Feb 2019 02:00:38 -0500 Received: from mail.kernel.org ([198.145.29.99]:45628 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726773AbfBOHAh (ORCPT ); Fri, 15 Feb 2019 02:00:37 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A777E21927; Fri, 15 Feb 2019 07:00:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550214033; bh=QvuU6OQQXmO+iO2uyK/vGfsXfea1cbNeulcpEwUm2vg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gv8SalMS7GATW7oE9ip0bggl0tsif+Beil8gWBM0b+Ue9KLqdi4aXz7MBQa75gzqT 65Nb+KVcK6hbEbZKA//iU4wX4uJOAXUOjTRgeeIfpTig59S/8Rp8Om8lGPeFTuueG+ bsnPpP8nunTyM17fg/lOcDmK0PIXvgmUTEMRMJqo= Date: Fri, 15 Feb 2019 08:00:22 +0100 From: Greg Kroah-Hartman To: Andrew Morton Cc: stable@vger.kernel.org, Linus Torvalds , Richard Weinberger , Samuel Dionne-Riel , LKML , graham@grahamc.com, Oleg Nesterov , Kees Cook , Michal Hocko Subject: Re: Userspace regression in LTS and stable kernels Message-ID: <20190215070022.GD14473@kroah.com> References: <20190214122027.c0df36282d65dc9979248117@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190214122027.c0df36282d65dc9979248117@linux-foundation.org> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 14, 2019 at 12:20:27PM -0800, Andrew Morton wrote: > On Thu, 14 Feb 2019 09:56:46 -0800 Linus Torvalds wrote: > > > On Wed, Feb 13, 2019 at 3:37 PM Richard Weinberger > > wrote: > > > > > > Your shebang line exceeds BINPRM_BUF_SIZE. > > > Before the said commit the kernel silently truncated the shebang line > > > (and corrupted it), > > > now it tells the user that the line is too long. > > > > It doesn't matter if it "corrupted" things by truncating it. All that > > matters is "it used to work, now it doesn't" > > > > Yes, maybe it never *should* have worked. And yes, it's sad that > > people apparently had cases that depended on this odd behavior, but > > there we are. > > > > I see that Kees has a patch to fix it up. > > > > Greg, I think we have a problem here. > > 8099b047ecc431518 ("exec: load_script: don't blindly truncate shebang > string") wasn't marked for backporting. And, presumably as a > consequence, Kees's fix "exec: load_script: allow interpreter argument > truncation" was not marked for backporting. > > 8099b047ecc431518 hasn't even appeared in a Linus released kernel, yet > it is now present in 4.9.x, 4.14.x, 4.19.x and 4.20.x. It came in 5.0-rc1, so it fits the "in a Linus released kernel" requirement. If we are to wait until it shows up in a -final, that would be months too late for almost all of these types of patches that are picked up. > I don't know if Oleg considered backporting that patch. I certainly > did (I always do), and I decided against doing so. Yet there it is. This came in through Sasha's tools, which give people a week or so to say "hey, this isn't a stable patch!" and it seems everyone ignored that :( Where is Kees's fix? I'll be glad to queue it up, or just revert the above commit, which ever people think is easiest. thanks, greg k-h