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 377AFC77B73 for ; Wed, 24 May 2023 13:51:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235491AbjEXNv4 (ORCPT ); Wed, 24 May 2023 09:51:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235431AbjEXNvz (ORCPT ); Wed, 24 May 2023 09:51:55 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0166AA9; Wed, 24 May 2023 06:51:53 -0700 (PDT) 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 92D6763385; Wed, 24 May 2023 13:51:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0D27C433EF; Wed, 24 May 2023 13:51:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684936313; bh=4GshjE8EW0mcvOVEahGR8w89BqqKhoLGoZQ3w7o8H08=; h=Date:From:To:CC:Subject:In-Reply-To:References:From; b=qb7DMQdqOOKgXs40GCoO7DiAHU3CqIJUwI6k/zcLHnFlxV0vPhuZ+ABymC3UdvBc+ jDVceNK4HT6uiJurdC9kJGtaCi53cui792N3JJezYf27fShgJO1/R1tJ27DiEicmWT 98Vetx7LGHGulW+FsTonnfiibRJ18SgXV9nmJ6AImrarvRLfbdO1sXrI5w/SUUUXVv f21t9Wz93Fl1AGuXVRxb8JbTECtyCYNV9xUdqtZwAz5cUge9EhdX6C+MwIswLWw30W r9mAc9oxqwQoPxAF0Adx59N5sFnSISZyikjIoXpZYrGFaVKJQlgVjOIwP9SiQd2/Vr JQVfl7gpDNkaw== Date: Wed, 24 May 2023 06:51:52 -0700 From: Kees Cook To: =?ISO-8859-1?Q?Daniel_D=EDaz?= , Vlastimil Babka CC: Greg Kroah-Hartman , Sasha Levin , linux- stable , open list , Kees Cook , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "open list:NETWORKING [GENERAL]" , ndesaulniers@google.com, rientjes@google.com, Sumit Semwal Subject: =?US-ASCII?Q?Re=3A_Stable_backport_request=3A_skbuff=3A_Pro?= =?US-ASCII?Q?actively_round_up_to_kmalloc_bucket_size?= User-Agent: K-9 Mail for Android In-Reply-To: References: Message-ID: <5A79C566-3213-456A-8CA3-8F0F1A2D9781@kernel.org> 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 On May 23, 2023 8:52:53 PM PDT, "Daniel D=C3=ADaz" wrote: >Hello! > >On Tue, 23 May 2023 at 00:28, Vlastimil Babka wrote: >> On 5/22/23 20:23, Daniel D=C3=ADaz wrote: >> > Hello! >> > >> > Would the stable maintainers please consider backporting the followin= g >> > commit to the 6=2E1? We are trying to build gki_defconfig (plus a few >> > extras) on Arm64 and test it under Qemu-arm64, but it fails to boot= =2E >> > Bisection has pointed here=2E >> >> You mean the bisection was done to find the first "good" commit between= 6=2E1 >> and e=2Eg=2E 6=2E3? >> >> As others said, this commit wasn't expected to be a fix to a known bug= =2E >> Maybe you found one that we didn't know of, or it might be accidentaly >> masking some other bug=2E > >How interesting! Yes, we happened to run a bisection between v6=2E1 and >v6=2E3 and we found where it started working with the following >configuration: > https://storage=2Etuxsuite=2Ecom/public/linaro/daniel/builds/2QA2CHQUpq= Ke27FyMZrBNILVwXi/config Ah yes, from CONFIG_UBSAN_BOUNDS=3Dy and CONFIG_UBSAN_TRAP=3Dy This was a known issue in upstream, oddly only exposed on arm64=2E Somethi= ng re-broke with __alloc_size after commit 93dd04ab0b2b had tried to work a= round it=2E I didn't think any kernel released with this broken, though, so= perhaps what broke it got added to -stable? >With that patch on top of v6=2E1=2E29 it boots fine under Qemu-arm64; as >v6=2E1=2Ey stands, it panics with this: It should be fine to backport the patch, IMO=2E --=20 Kees Cook