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=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 DE484C433E7 for ; Thu, 8 Oct 2020 20:02:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7B9A422226 for ; Thu, 8 Oct 2020 20:02:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qJH2yWmR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729897AbgJHUC4 (ORCPT ); Thu, 8 Oct 2020 16:02:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729877AbgJHUC4 (ORCPT ); Thu, 8 Oct 2020 16:02:56 -0400 Received: from mail-il1-x142.google.com (mail-il1-x142.google.com [IPv6:2607:f8b0:4864:20::142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 43F6BC0613D2 for ; Thu, 8 Oct 2020 13:02:56 -0700 (PDT) Received: by mail-il1-x142.google.com with SMTP id o9so2472522ilo.0 for ; Thu, 08 Oct 2020 13:02:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=EpFqPi/WffB740uEvA80XvaKjJGc1YrmBO/U3WKT3uc=; b=qJH2yWmRIMLZQcn9zTNgJh5eiSHwX3BbFv3xg/VC2LkJSBZQ1143aYpFmQ7+QeLbOi zi/B/BCOlrvMOmZgKthveSTei381zf16XqXNYCrKQzYjKs5VIbj1fNKL/46N86K4gq5J dObEFswQGBXW0Rng47V5SV3uyvQ643wx9StcViAXx6pWQezaJai/mpVbf28S8WliflQ1 1Vz06/NgL1rHViH+h65x4Dz3FeBUbKa3If+1dna5mwdQSDwNkBlnVA4C67gO3gDISDG0 6AyfTZWXZyt5BFlV2+vy6hIIkvq4JqmNp7jHhYdX/e9qQRWq32ASZApXctxkTZBOJA0l 0uUA== 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=EpFqPi/WffB740uEvA80XvaKjJGc1YrmBO/U3WKT3uc=; b=I1mjmRtCufA3cLgpp38a5h/WhVlCve09x84MdxnLs06zoOnyct+DuEh4QzyFA5FWs/ lWi8n8vJh+JK4XYCFEpglOT2srXq3hBhfCORG7a8l6HAqvGOBd6pmiDUj4Bg0fnu9bpo TZA4DYWvtXFoVQP0Wsyb5KFD8BuSAV6DbFRCSUZ0nuPUiMJ+3DW8Sz/EUF4c6PNrtBk2 tx/2ZyhzmLeJsIFynvDAWTNEr6XhKKvGKYuxpEAaXb86K/UFfKU+jA8oFaJWVhY81lP+ jZTo4As92AwTjw20yPIbdyPja4ZzgBGdwaQ52+B9q3Lpdf3uT5rzofyy2/P0gXwfnJ5Z 8bXw== X-Gm-Message-State: AOAM531AIV0NAyt6OU063n/gN7wMKLfTI2jeRzuacFgJrxhoflgZBgRX ZinJgN+DjLFs45T5ywAhdN1UiBtG1CIyGoYWVjA= X-Google-Smtp-Source: ABdhPJytNGdqx217iwP5BFdieo/eqCBD+SnhTcUIUS9CeOYOiwHBKII9DTj7XOaP0xxrnDZ54D2w52GchdK0xgizXpg= X-Received: by 2002:a92:7751:: with SMTP id s78mr5401483ilc.144.1602187375550; Thu, 08 Oct 2020 13:02:55 -0700 (PDT) MIME-Version: 1.0 References: <20201008061821.24663-1-xiyou.wangcong@gmail.com> <20201008103410.4fea97a5@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20201008103410.4fea97a5@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> From: Cong Wang Date: Thu, 8 Oct 2020 13:02:44 -0700 Message-ID: Subject: Re: [Patch net] can: initialize skbcnt in j1939_tp_tx_dat_new() To: Jakub Kicinski Cc: Linux Kernel Network Developers , syzbot+3f3837e61a48d32b495f@syzkaller.appspotmail.com, Robin van der Gracht , Oleksij Rempel , Pengutronix Kernel Team , Oliver Hartkopp , Marc Kleine-Budde Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Oct 8, 2020 at 10:34 AM Jakub Kicinski wrote: > > On Wed, 7 Oct 2020 23:18:21 -0700 Cong Wang wrote: > > This fixes an uninit-value warning: > > BUG: KMSAN: uninit-value in can_receive+0x26b/0x630 net/can/af_can.c:650 > > > > Reported-and-tested-by: syzbot+3f3837e61a48d32b495f@syzkaller.appspotmail.com > > Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") > > Cc: Robin van der Gracht > > Cc: Oleksij Rempel > > Cc: Pengutronix Kernel Team > > Cc: Oliver Hartkopp > > Cc: Marc Kleine-Budde > > Signed-off-by: Cong Wang > > --- > > net/can/j1939/transport.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c > > index 0cec4152f979..88cf1062e1e9 100644 > > --- a/net/can/j1939/transport.c > > +++ b/net/can/j1939/transport.c > > @@ -580,6 +580,7 @@ sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv, > > skb->dev = priv->ndev; > > can_skb_reserve(skb); > > can_skb_prv(skb)->ifindex = priv->ndev->ifindex; > > + can_skb_prv(skb)->skbcnt = 0; > > /* reserve CAN header */ > > skb_reserve(skb, offsetof(struct can_frame, data)); > > Thanks! Looks like there is another can_skb_reserve(skb) on line 1489, > is that one fine? I don't know, I only attempt to address the syzbot report. To me, it at least does not harm to fix that one too. I am fine either way. Thanks.