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=-8.1 required=3.0 tests=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,USER_AGENT_SANE_1 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 8FFAAC35671 for ; Sat, 22 Feb 2020 06:56:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 60F9120707 for ; Sat, 22 Feb 2020 06:56:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="dPURgE2L" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727244AbgBVG4O (ORCPT ); Sat, 22 Feb 2020 01:56:14 -0500 Received: from mail-pf1-f194.google.com ([209.85.210.194]:39344 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727080AbgBVG4N (ORCPT ); Sat, 22 Feb 2020 01:56:13 -0500 Received: by mail-pf1-f194.google.com with SMTP id 84so2460198pfy.6; Fri, 21 Feb 2020 22:56:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=P1m+5CvuP9WCDPeB2rpqQfl3ZDcAcnZi8bxAc6P+hRk=; b=dPURgE2Lm4GaZRYbjxHDP2B3otEz+xUJEcA5i3LVcJjawKYEdOuzaftuH86Hvn+z2u p/HVStoCr46D2r7vAdKIPPtDTw4Ri6UvouwJXuUMdRnjZR1uRFWRzplttwg9dEQVxU19 1NG0zIrux8y1zMOTymtU3BKJ784cQOyQRz5msCWx/YsIFqY961KYxuzX3vGbVwouhQQz ik8FgDZLGYnmcK/wYxvm6zW8PFY+Z5VTTRXJXHAH5fTCVu26af795nwaVHxInjqxlJoD Ypo8gnLH4AqjLeMSFFSB4nCkVEYNbTnuLJM9gTLI/IxYz+6WNlc5FJztHC4QepS+LQ0x j1Ig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=P1m+5CvuP9WCDPeB2rpqQfl3ZDcAcnZi8bxAc6P+hRk=; b=pFFGm2OYdezz9RIN+NiokpC6oFQTjf9OFow8vQtWIj+gdssLPpLkI3TOqOZuwm4TQK XsIW0URTXLn+HqYBJ7IPFPrRq6drpQI1HJxIt/Cc/6ntsclADWbbWgNkcVFtpl1hN6iB qDTWnpIdPSqdyjaiZrJrnJjeU9oj8KBa8EEvh24iUNw+fVBEcqbkE0SXl1er8gGekshk MZwFvNPHd749kbNvxAatidVyWnzuWDZ5Hd6z2i0eS9Ub10JtCQ9w3otpuRolZJ6+HeS1 7fmgLFGTFZ0JNn9VDvitX7SriNPIexrYmUL764IICEuUc8as5tquxf/5A9v5yZa7sGVU drAg== X-Gm-Message-State: APjAAAUkumCcKlqbo6Zze+Bkro+jhTEBPHNY4NdYVv04XTDOXyizJsJq 8Oa+vO8heBsATRbUaHAOdw== X-Google-Smtp-Source: APXvYqwowHvFtBe6LpkACUng2s38E8ahG4DvKaIDLCfgUrVAiTcya7q3HI8cDbC0aT0bMh1HGsTSXA== X-Received: by 2002:aa7:9359:: with SMTP id 25mr41508430pfn.188.1582354573071; Fri, 21 Feb 2020 22:56:13 -0800 (PST) Received: from madhuparna-HP-Notebook ([42.109.147.216]) by smtp.gmail.com with ESMTPSA id z127sm4456084pgb.64.2020.02.21.22.56.09 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 21 Feb 2020 22:56:12 -0800 (PST) From: Madhuparna Bhowmik X-Google-Original-From: Madhuparna Bhowmik Date: Sat, 22 Feb 2020 12:25:36 +0530 To: Jiri Pirko Cc: madhuparnabhowmik10@gmail.com, jiri@mellanox.com, davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, joel@joelfernandes.org, frextrite@gmail.com, linux-kernel-mentees@lists.linuxfoundation.org, paulmck@kernel.org Subject: Re: [PATCH] net: core: devlink.c: Hold devlink->lock from the beginning of devlink_dpipe_table_register() Message-ID: <20200222065536.GA9143@madhuparna-HP-Notebook> References: <20200221180943.17415-1-madhuparnabhowmik10@gmail.com> <20200222062640.GA2228@nanopsycho> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200222062640.GA2228@nanopsycho> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 22, 2020 at 07:26:40AM +0100, Jiri Pirko wrote: > Fri, Feb 21, 2020 at 07:09:43PM CET, madhuparnabhowmik10@gmail.com wrote: > >From: Madhuparna Bhowmik > > > >devlink_dpipe_table_find() should be called under either > >rcu_read_lock() or devlink->lock. devlink_dpipe_table_register() > >calls devlink_dpipe_table_find() without holding the lock > >and acquires it later. Therefore hold the devlink->lock > >from the beginning of devlink_dpipe_table_register(). > > > >Suggested-by: Jiri Pirko > >Signed-off-by: Madhuparna Bhowmik > >--- > > net/core/devlink.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > >diff --git a/net/core/devlink.c b/net/core/devlink.c > >index 3e8c94155d93..d54e1f156b6f 100644 > >--- a/net/core/devlink.c > >+++ b/net/core/devlink.c > >@@ -6840,6 +6840,8 @@ int devlink_dpipe_table_register(struct devlink *devlink, > > { > > struct devlink_dpipe_table *table; > > > >+ mutex_lock(&devlink->lock); > >+ > > if (devlink_dpipe_table_find(&devlink->dpipe_table_list, table_name)) > > return -EEXIST; > > You have to handle the error path. > Sure, I have sent the updated patch. Thank you, Madhuparna > > > > >@@ -6855,7 +6857,6 @@ int devlink_dpipe_table_register(struct devlink *devlink, > > table->priv = priv; > > table->counter_control_extern = counter_control_extern; > > > >- mutex_lock(&devlink->lock); > > list_add_tail_rcu(&table->list, &devlink->dpipe_table_list); > > mutex_unlock(&devlink->lock); > > return 0; > >-- > >2.17.1 > >