From patchwork Sun Jan 29 16:51:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leon Romanovsky X-Patchwork-Id: 13120189 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8869CC05027 for ; Sun, 29 Jan 2023 16:51:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235048AbjA2Qvs (ORCPT ); Sun, 29 Jan 2023 11:51:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229549AbjA2Qvr (ORCPT ); Sun, 29 Jan 2023 11:51:47 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 981AC199E3 for ; Sun, 29 Jan 2023 08:51:45 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 56C81B80D1E for ; Sun, 29 Jan 2023 16:51:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27D11C433EF; Sun, 29 Jan 2023 16:51:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675011102; bh=wzbKWWsRbq/c7gH7l1JPBzo88Nx1RGSRDtrdVJtRoys=; h=From:To:Cc:Subject:Date:From; b=RUXL5nLao3qGEVMbtVou4OJnAta75I/CF/PCAxFnvQPQXYMMuqND6txLPt4N0+cQT UBEwYsQSmuGDk8XDfx4OZxkNI7MO6rMM7oS4Tlb4zdSQRHXGSVrISQKeweQOU2nPAB IoGD6cv9Q1cbO7gctGc87vU4Es8jyUwD9wB44Bg1ErDF4SAd1cmDofdUNXzgGvpizw 3GNkIfpojeGJN8BuQ4mwP8effFiIel39YM/6o4Fl3h0m3VeNhyjoKm+joJD74bu2Zk LQYX5NAQSGgMurgZ09A91kERxr/gSNzLx3oPb+LssCsoXaZzWKCXmesXLY2sIzUbCc upcZu0QHOXpNw== From: Leon Romanovsky To: "David S . Miller" , Jakub Kicinski Cc: Andrew Lunn , bridge@lists.linux-foundation.org, Eric Dumazet , Florian Fainelli , Herbert Xu , netdev@vger.kernel.org, Nikolay Aleksandrov , Paolo Abeni , Roopa Prabhu , Steffen Klassert , Vladimir Oltean Subject: [PATCH net-next v2] netlink: provide an ability to set default extack message Date: Sun, 29 Jan 2023 18:51:37 +0200 Message-Id: X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org In netdev common pattern, extack pointer is forwarded to the drivers to be filled with error message. However, the caller can easily overwrite the filled message. Instead of adding multiple "if (!extack->_msg)" checks before any NL_SET_ERR_MSG() call, which appears after call to the driver, let's add new macro to common code. [1] https://lore.kernel.org/all/Y9Irgrgf3uxOjwUm@unreal Signed-off-by: Leon Romanovsky Reviewed-by: Simon Horman Reviewed-by: Nikolay Aleksandrov --- Changelog: v2: * Removed () brackets around msg to fix compilation error. v1: https://lore.kernel.org/all/d4843760219f20367c27472f084bd8aa729cf321.1674995155.git.leon@kernel.org * Added special *_WEAK() macro instead of embedding same check in NL_SET_ERR_MSG_MOD/NL_SET_ERR_MSG_FMT. * Reuse same macro for XFRM code which triggered this patch. v0: https://lore.kernel.org/all/2919eb55e2e9b92265a3ba600afc8137a901ae5f.1674760340.git.leon@kernel.org --- include/linux/netlink.h | 10 ++++++++++ net/bridge/br_switchdev.c | 10 ++++------ net/dsa/master.c | 4 +--- net/dsa/slave.c | 4 +--- net/xfrm/xfrm_device.c | 5 ++++- 5 files changed, 20 insertions(+), 13 deletions(-) diff --git a/include/linux/netlink.h b/include/linux/netlink.h index fa4d86da0ec7..c43ac7690eca 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -130,6 +130,16 @@ struct netlink_ext_ack { #define NL_SET_ERR_MSG_FMT_MOD(extack, fmt, args...) \ NL_SET_ERR_MSG_FMT((extack), KBUILD_MODNAME ": " fmt, ##args) +#define NL_SET_ERR_MSG_WEAK(extack, msg) do { \ + if ((extack) && !(extack)->_msg) \ + NL_SET_ERR_MSG((extack), msg); \ +} while (0) + +#define NL_SET_ERR_MSG_WEAK_MOD(extack, msg) do { \ + if ((extack) && !(extack)->_msg) \ + NL_SET_ERR_MSG_MOD((extack), msg); \ +} while (0) + #define NL_SET_BAD_ATTR_POLICY(extack, attr, pol) do { \ if ((extack)) { \ (extack)->bad_attr = (attr); \ diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c index 7eb6fd5bb917..de18e9c1d7a7 100644 --- a/net/bridge/br_switchdev.c +++ b/net/bridge/br_switchdev.c @@ -104,9 +104,8 @@ int br_switchdev_set_port_flag(struct net_bridge_port *p, return 0; if (err) { - if (extack && !extack->_msg) - NL_SET_ERR_MSG_MOD(extack, - "bridge flag offload is not supported"); + NL_SET_ERR_MSG_WEAK_MOD(extack, + "bridge flag offload is not supported"); return -EOPNOTSUPP; } @@ -115,9 +114,8 @@ int br_switchdev_set_port_flag(struct net_bridge_port *p, err = switchdev_port_attr_set(p->dev, &attr, extack); if (err) { - if (extack && !extack->_msg) - NL_SET_ERR_MSG_MOD(extack, - "error setting offload flag on port"); + NL_SET_ERR_MSG_WEAK_MOD(extack, + "error setting offload flag on port"); return err; } diff --git a/net/dsa/master.c b/net/dsa/master.c index 26d90140d271..1507b8cdb360 100644 --- a/net/dsa/master.c +++ b/net/dsa/master.c @@ -464,9 +464,7 @@ int dsa_master_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp, err = dsa_port_lag_join(cpu_dp, lag_dev, uinfo, extack); if (err) { - if (extack && !extack->_msg) - NL_SET_ERR_MSG_MOD(extack, - "CPU port failed to join LAG"); + NL_SET_ERR_MSG_WEAK_MOD(extack, "CPU port failed to join LAG"); goto out_master_teardown; } diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 6014ac3aad34..26c458f50ac6 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -2692,9 +2692,7 @@ static int dsa_slave_changeupper(struct net_device *dev, if (!err) dsa_bridge_mtu_normalization(dp); if (err == -EOPNOTSUPP) { - if (extack && !extack->_msg) - NL_SET_ERR_MSG_MOD(extack, - "Offloading not supported"); + NL_SET_ERR_MSG_WEAK_MOD(extack, "Offloading not supported"); err = 0; } err = notifier_from_errno(err); diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c index 562b9d951598..95f1436bf6a2 100644 --- a/net/xfrm/xfrm_device.c +++ b/net/xfrm/xfrm_device.c @@ -325,8 +325,10 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x, * authors to do not return -EOPNOTSUPP in packet offload mode. */ WARN_ON(err == -EOPNOTSUPP && is_packet_offload); - if (err != -EOPNOTSUPP || is_packet_offload) + if (err != -EOPNOTSUPP || is_packet_offload) { + NL_SET_ERR_MSG_WEAK(extack, "Device failed to offload this state"); return err; + } } return 0; @@ -388,6 +390,7 @@ int xfrm_dev_policy_add(struct net *net, struct xfrm_policy *xp, xdo->type = XFRM_DEV_OFFLOAD_UNSPECIFIED; xdo->dir = 0; netdev_put(dev, &xdo->dev_tracker); + NL_SET_ERR_MSG_WEAK(extack, "Device failed to offload this policy"); return err; }