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=-13.6 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 1291EC433E0 for ; Fri, 8 Jan 2021 09:36:42 +0000 (UTC) Received: from lists.zx2c4.com (lists.zx2c4.com [165.227.139.114]) (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 E78B923383 for ; Fri, 8 Jan 2021 09:36:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E78B923383 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=wireguard-bounces@lists.zx2c4.com Received: by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 2fb8e885; Fri, 8 Jan 2021 09:33:34 +0000 (UTC) Received: from mail-qk1-x72a.google.com (mail-qk1-x72a.google.com [2607:f8b0:4864:20::72a]) by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTPS id ff69f96e (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO) for ; Fri, 8 Jan 2021 09:33:32 +0000 (UTC) Received: by mail-qk1-x72a.google.com with SMTP id 186so7960009qkj.3 for ; Fri, 08 Jan 2021 01:33:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=PnLbusFPw0NqkYaHXS7jwwZf+CC6BlEDfblZZAjXZmc=; b=EiBwMyvADldbeeFFxd7qdO/JeI9YJxmiB/3XltO54PGT472GgYmaCBo7qmcebT4h1n bDBFVu0K/N7UpktoNxNwYewCXwYV+Fu3MNtmafhcCjapYKDrlK5SaYOE1wU7CNG5L3XG /w4MdA5Jm2jHUIbk3py1Q1rNJbPYQTEzUNVTrwLj1mPOdd1QctK+P7SmlRGX3kdFEfz2 VdAj9ZD1Y9W2VfMxbekDvMu76cF1bG9l2KqGypVYuCk/0Ca3LD6eTol2/zIz8ZEq3XB9 CGip9DcjXHs3p7qJN4WWrPDon/HJYCLrPyR6vVErKNAOqOH3aWR2lg9hMGAEmGGHs28c ksOQ== 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=PnLbusFPw0NqkYaHXS7jwwZf+CC6BlEDfblZZAjXZmc=; b=UgZm35fyLPeH9MK62ys79H4GdIO3/JHdkD4sK44JZzH39lLZjwR0b5fMe1PVgAA+Wn ESdi4L8vodxJxdvWCo5+sq3H41XyyJj9WDPV8C/vDijyHMx33n9GQs0edzEQ3B/bNOUX vdAkOZB2LVehZzp6CO/ujiOD4I0aIQtul4kWoy1ObfvmBdxgZP4AI+jui+ZDiLdY8itj 2Y6v6zXFgXWStAAbGz98OluaWyQbSc1HFM5H5frwqcuoZu99SZD29o62k9cir24C+9u3 Vy7/54wJLe0XkY4QdX6LxijRK0pGV0uznpL8FPwfek0sr3/qbbSPhV1KdHQGl1jiDKCD TAJA== X-Gm-Message-State: AOAM533kVp0Fmh6YecZql843ywTQ7kxYH7e4PlnzAPbxiavThQz0vTbv kGSLdjBtcwTuomQZbLu0WiiUEb4+QL3d0mu9WwJlBA== X-Google-Smtp-Source: ABdhPJwoR7gUITNVyUOAEyZRNWl7p5el7UTrmj/K02apfnRIgeVk0q5jElVkY1Q+z4CE+Pb2RUb0XwiJc695IHluFnw= X-Received: by 2002:a05:620a:983:: with SMTP id x3mr3074511qkx.231.1610098410717; Fri, 08 Jan 2021 01:33:30 -0800 (PST) MIME-Version: 1.0 References: <000000000000e13e2905b6e830bb@google.com> In-Reply-To: From: Dmitry Vyukov Date: Fri, 8 Jan 2021 10:33:19 +0100 Message-ID: Subject: Re: UBSAN: object-size-mismatch in wg_xmit To: noloader@gmail.com Cc: "Jason A. Donenfeld" , Netdev , syzkaller-bugs , WireGuard mailing list Content-Type: text/plain; charset="UTF-8" X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" On Thu, Jan 7, 2021 at 8:06 PM Jeffrey Walton wrote: > > On Thu, Jan 7, 2021 at 2:03 PM Jason A. Donenfeld wrote: > > > > On Thu, Jan 7, 2021 at 1:22 PM Dmitry Vyukov wrote: > > > > > > On Mon, Dec 21, 2020 at 12:23 PM Jason A. Donenfeld wrote: > > > > > > > > ... > > > > > > These UBSAN checks were just enabled recently. > > > It's indeed super easy to trigger: 133083 VMs were crashed on this already: > > > https://syzkaller.appspot.com/bug?extid=8f90d005ab2d22342b6d > > > So it's one of the top crashers by now. > > > > Ahh, makes sense. So it is easily reproducible after all. > > > > You're still of the opinion that it's a false positive, right? I > > shouldn't spend more cycles on this? > > You might consider making a test build with -fno-lto in case LTO is > mucking things up. > > Google Posts Patches So The Linux Kernel Can Be LTO-Optimized By > Clang, https://www.phoronix.com/scan.php?page=news_item&px=Linux-Kernel-Clang-LTO-Patches Hi Jeff, Are these patches upstream now? syzbot doesn't enable LTO intentionally, nor I see CONFIG_LTO in the provided config.