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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 DB26BC47098 for ; Mon, 31 May 2021 16:18:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BA7C161376 for ; Mon, 31 May 2021 16:18:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234792AbhEaQTy (ORCPT ); Mon, 31 May 2021 12:19:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:37024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232106AbhEaOmK (ORCPT ); Mon, 31 May 2021 10:42:10 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1751E61C71; Mon, 31 May 2021 13:53:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1622469240; bh=oP517+rIBNt+5HX5RsjOP/NTxSLiEzw8RyYNpIdx35M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uTwkp2Ko84sa7m8bXZaQEpAAd7K5R+/lrhMOFm0R3udf9JuWt55LFEdy8me0v9djM 5v+c83rRoU72T13JiQBpn4O/1vY7jGUx0hluEBs7bfe7df6nCBP7ZVOvulcv5Y2jFS rvBr/2QE9AQ4BxoE8AWLZelG55LHlgag5OGrLvTE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dima Chumak , Vlad Buslov , Saeed Mahameed Subject: [PATCH 5.12 122/296] net/mlx5e: Fix nullptr in mlx5e_tc_add_fdb_flow() Date: Mon, 31 May 2021 15:12:57 +0200 Message-Id: <20210531130708.010566858@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210531130703.762129381@linuxfoundation.org> References: <20210531130703.762129381@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dima Chumak commit fe7738eb3ca3631a75844e790f6cb576c0fe7b00 upstream. The result of __dev_get_by_index() is not checked for NULL, which then passed to mlx5e_attach_encap() and gets dereferenced. Also, in case of a successful lookup, the net_device reference count is not incremented, which may result in net_device pointer becoming invalid at any time during mlx5e_attach_encap() execution. Fix by using dev_get_by_index(), which does proper reference counting on the net_device pointer. Also, handle nullptr return value when mirred device is not found. It's safe to call dev_put() on the mirred net_device pointer, right after mlx5e_attach_encap() call, because it's not being saved/copied down the call chain. Fixes: 3c37745ec614 ("net/mlx5e: Properly deal with encap flows add/del under neigh update") Addresses-Coverity: ("Dereference null return value") Signed-off-by: Dima Chumak Reviewed-by: Vlad Buslov Signed-off-by: Saeed Mahameed Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) --- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c @@ -1276,10 +1276,10 @@ mlx5e_tc_add_fdb_flow(struct mlx5e_priv struct netlink_ext_ack *extack) { struct mlx5_eswitch *esw = priv->mdev->priv.eswitch; - struct net_device *out_dev, *encap_dev = NULL; struct mlx5e_tc_flow_parse_attr *parse_attr; struct mlx5_flow_attr *attr = flow->attr; bool vf_tun = false, encap_valid = true; + struct net_device *encap_dev = NULL; struct mlx5_esw_flow_attr *esw_attr; struct mlx5_fc *counter = NULL; struct mlx5e_rep_priv *rpriv; @@ -1325,16 +1325,22 @@ mlx5e_tc_add_fdb_flow(struct mlx5e_priv esw_attr = attr->esw_attr; for (out_index = 0; out_index < MLX5_MAX_FLOW_FWD_VPORTS; out_index++) { + struct net_device *out_dev; int mirred_ifindex; if (!(esw_attr->dests[out_index].flags & MLX5_ESW_DEST_ENCAP)) continue; mirred_ifindex = parse_attr->mirred_ifindex[out_index]; - out_dev = __dev_get_by_index(dev_net(priv->netdev), - mirred_ifindex); + out_dev = dev_get_by_index(dev_net(priv->netdev), mirred_ifindex); + if (!out_dev) { + NL_SET_ERR_MSG_MOD(extack, "Requested mirred device not found"); + err = -ENODEV; + goto err_out; + } err = mlx5e_attach_encap(priv, flow, out_dev, out_index, extack, &encap_dev, &encap_valid); + dev_put(out_dev); if (err) goto err_out;