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=-8.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, 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 DF7C8C433E0 for ; Wed, 10 Feb 2021 14:03:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C0C660C3F for ; Wed, 10 Feb 2021 14:03:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230263AbhBJODC (ORCPT ); Wed, 10 Feb 2021 09:03:02 -0500 Received: from wout3-smtp.messagingengine.com ([64.147.123.19]:43771 "EHLO wout3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231947AbhBJOC1 (ORCPT ); Wed, 10 Feb 2021 09:02:27 -0500 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.west.internal (Postfix) with ESMTP id 7F3F8C32; Wed, 10 Feb 2021 09:01:20 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Wed, 10 Feb 2021 09:01:20 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=YbXhKy n1szkD0P/rV2pG5sEz2cQTVf4lnrgydyJ+lNA=; b=iZLJMl/EHCmsxaswAlLlVq ujkJPg1NrY4FqF3WIL0GPhW/AamlakmsXV+eiYqVIoUUTc7iJw7Ri6aYHyp/kOvj QXTBrkqPkwYM5fAfpg6tnLD8RMERgvf9QuiEj6zpuE9VdIKDEl8v9XilD9dFkT7O Fxjja6QoL48WA1k8FWSCpwmzBnlYCfj9Ckarc9vCPia258L4e8z7leGqrxhVd8cX efB9YvPuyN3ZsyhzaYm1+ul9ySJw7ZGe/lLbiqI/f0UBJsE4/H31HXXY485aXBb6 CYFgFssrboTVh1VApUk52ARwq4wqyiiwg0AYbpmI7ArIopos+K59zGlrtoHaEUow == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledrheejgdehlecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujgesthdtredttddtvdenucfhrhhomhepkfguohcuufgt hhhimhhmvghluceoihguohhstghhsehiughoshgthhdrohhrgheqnecuggftrfgrthhtvg hrnheptdffkeekfeduffevgeeujeffjefhtefgueeugfevtdeiheduueeukefhudehleet necukfhppeekgedrvddvledrudehfedrgeegnecuvehluhhsthgvrhfuihiivgeptdenuc frrghrrghmpehmrghilhhfrhhomhepihguohhstghhsehiughoshgthhdrohhrgh X-ME-Proxy: Received: from localhost (igld-84-229-153-44.inter.net.il [84.229.153.44]) by mail.messagingengine.com (Postfix) with ESMTPA id D4595108005B; Wed, 10 Feb 2021 09:01:18 -0500 (EST) Date: Wed, 10 Feb 2021 16:01:15 +0200 From: Ido Schimmel To: Vlad Buslov Cc: Dan Carpenter , jiri@resnulli.us, linux-rdma@vger.kernel.org Subject: Re: [bug report] net/mlx5e: Handle FIB events to update tunnel endpoint device Message-ID: <20210210140115.GA300383@shredder.lan> References: <20210210132137.GA296697@shredder.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Wed, Feb 10, 2021 at 03:50:03PM +0200, Vlad Buslov wrote: > > On Wed 10 Feb 2021 at 15:21, Ido Schimmel wrote: > > On Wed, Feb 10, 2021 at 01:55:23PM +0200, Vlad Buslov wrote: > >> On Wed 10 Feb 2021 at 13:08, Dan Carpenter wrote: > >> > Hello Vlad Buslov, > >> > > >> > The patch 8914add2c9e5: "net/mlx5e: Handle FIB events to update > >> > tunnel endpoint device" from Jan 25, 2021, leads to the following > >> > static checker warning: > >> > > >> > drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c:1639 mlx5e_tc_tun_init() > >> > error: passing non negative 1 to ERR_PTR > >> > > >> > drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c > >> > 1622 struct mlx5e_tc_tun_encap *mlx5e_tc_tun_init(struct mlx5e_priv *priv) > >> > 1623 { > >> > 1624 struct mlx5e_tc_tun_encap *encap; > >> > 1625 int err; > >> > 1626 > >> > 1627 encap = kvzalloc(sizeof(*encap), GFP_KERNEL); > >> > 1628 if (!encap) > >> > 1629 return ERR_PTR(-ENOMEM); > >> > 1630 > >> > 1631 encap->priv = priv; > >> > 1632 encap->fib_nb.notifier_call = mlx5e_tc_tun_fib_event; > >> > 1633 spin_lock_init(&encap->route_lock); > >> > 1634 hash_init(encap->route_tbl); > >> > 1635 err = register_fib_notifier(dev_net(priv->netdev), &encap->fib_nb, > >> > 1636 NULL, NULL); > >> > > >> > register_fib_notifier() calls fib_net_dump() which eventually calls > >> > fib6_walk_continue() which can return 1 if "walk is incomplete (i.e. > >> > suspended)". > >> > > >> > 1637 if (err) { > >> > 1638 kvfree(encap); > >> > 1639 return ERR_PTR(err); > >> > > >> > If this returns 1 it will eventually lead to an Oops. > >> > >> Hi Dan, > >> > >> Thanks for the bug report! > >> > >> This looks a bit strange to me because none of the other users of this > >> API handle positive error code in any special way (including reference > >> netdevsim implementation). Maybe API itself should be fixed? Jiri, Ido, > >> what do you think? > > > > The other functions that call register_fib_notifier() return an int, but > > mlx5e_tc_tun_init() returns a pointer. I think that's why it was > > flagged: "error: passing non negative 1 to ERR_PTR". > > Actually, some of them do. I mentioned netdevsim specifically because > nsim_fib_create() returns pointer and also casts return value of > register_fib_notifier() with ERR_PTR. > > > > > fib6_walk_continue() cannot return a positive value when called from > > register_fib_notifier(), but ignoring it means that you will keep > > getting the same static analysis error. What about: > > > > diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c > > index f43e27555725..ef9d022e693f 100644 > > --- a/net/ipv6/ip6_fib.c > > +++ b/net/ipv6/ip6_fib.c > > @@ -499,7 +499,7 @@ int fib6_tables_dump(struct net *net, struct notifier_block *nb, > > > > hlist_for_each_entry_rcu(tb, head, tb6_hlist) { > > err = fib6_table_dump(net, tb, w); > > - if (err < 0) > > + if (err) > > goto out; > > } > > } > > @@ -507,7 +507,8 @@ int fib6_tables_dump(struct net *net, struct notifier_block *nb, > > out: > > kfree(w); > > > > - return err; > > + /* The tree traversal function should never return a positive value. */ > > + return err > 0 ? -EINVAL : err; > > } > > > > static int fib6_dump_node(struct fib6_walker *w) > > > > Makes sense. You want me to send the fix or you will do it? Can you send to linux-internal and then I will apply it to our regression and let you know tomorrow morning? > > >> > >> Regards, > >> Vlad > >> > >> > > >> > 1640 } > >> > 1641 > >> > 1642 return encap; > >> > 1643 } > >> > > >> > regards, > >> > dan carpenter > >> >