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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 9D1BFC433FF for ; Mon, 12 Aug 2019 04:37:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70A78216F4 for ; Mon, 12 Aug 2019 04:37:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726600AbfHLEhm (ORCPT ); Mon, 12 Aug 2019 00:37:42 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:38722 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725808AbfHLEhl (ORCPT ); Mon, 12 Aug 2019 00:37:41 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id E40C014017D83; Sun, 11 Aug 2019 21:37:40 -0700 (PDT) Date: Sun, 11 Aug 2019 21:37:40 -0700 (PDT) Message-Id: <20190811.213740.2137488837577705437.davem@davemloft.net> To: wens@kernel.org Cc: andrew@lunn.ch, vivien.didelot@gmail.com, f.fainelli@gmail.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net v3] net: dsa: Check existence of .port_mdb_add callback before calling it From: David Miller In-Reply-To: <20190811141825.11566-1-wens@kernel.org> References: <20190811141825.11566-1-wens@kernel.org> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sun, 11 Aug 2019 21:37:41 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chen-Yu Tsai Date: Sun, 11 Aug 2019 22:18:25 +0800 > From: Chen-Yu Tsai > > The dsa framework has optional .port_mdb_{prepare,add,del} callback fields > for drivers to handle multicast database entries. When adding an entry, the > framework goes through a prepare phase, then a commit phase. Drivers not > providing these callbacks should be detected in the prepare phase. > > DSA core may still bypass the bridge layer and call the dsa_port_mdb_add > function directly with no prepare phase or no switchdev trans object, > and the framework ends up calling an undefined .port_mdb_add callback. > This results in a NULL pointer dereference, as shown in the log below. > > The other functions seem to be properly guarded. Do the same for > .port_mdb_add in dsa_switch_mdb_add_bitmap() as well. ... > Fixes: e6db98db8a95 ("net: dsa: add switch mdb bitmap functions") > Signed-off-by: Chen-Yu Tsai Applied and queued up for -stable, thanks.