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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 B9EA9C32751 for ; Wed, 31 Jul 2019 13:35:57 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 70759208C3 for ; Wed, 31 Jul 2019 13:35:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 70759208C3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45zDvr3MbgzDqc8 for ; Wed, 31 Jul 2019 23:35:52 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45zBnm41L7zDqc1 for ; Wed, 31 Jul 2019 22:00:28 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 45zBnm180Pz9sN4; Wed, 31 Jul 2019 22:00:27 +1000 (AEST) From: Michael Ellerman To: bugzilla-daemon@bugzilla.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [Bug 204371] BUG kmalloc-4k (Tainted: G W ): Object padding overwritten In-Reply-To: References: Date: Wed, 31 Jul 2019 22:00:27 +1000 Message-ID: <878ssequqs.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" bugzilla-daemon@bugzilla.kernel.org writes: > https://bugzilla.kernel.org/show_bug.cgi?id=204371 > > --- Comment #2 from Andrew Morton (akpm@linux-foundation.org) --- > (switched to email. Please respond via emailed reply-to-all, not via the > bugzilla web interface). > > > On Mon, 29 Jul 2019 22:35:48 +0000 bugzilla-daemon@bugzilla.kernel.org wrote: > >> https://bugzilla.kernel.org/show_bug.cgi?id=204371 >> >> Bug ID: 204371 >> Summary: BUG kmalloc-4k (Tainted: G W ): Object >> padding overwritten >> Product: Memory Management >> Version: 2.5 >> Kernel Version: 5.3.0-rc2 >> Hardware: PPC-32 >> OS: Linux >> Tree: Mainline >> Status: NEW >> Severity: normal >> Priority: P1 >> Component: Slab Allocator >> Assignee: akpm@linux-foundation.org >> Reporter: erhard_f@mailbox.org >> Regression: No > > cc'ing various people here. > > I suspect proc_cgroup_show() is innocent and that perhaps > bpf_prepare_filter() had a memory scribble. iirc there has been at > least one recent pretty serious bpf fix applied recently. Can others > please take a look? I haven't been able to reproduce this on a 64-bit or 32-bit powerpc machine here. But I don't run gentoo userspace, so I suspect I'm not tripping the same path at boot. I did run the seccomp selftest and that didn't trip it either. cheers