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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66D9DC4708E for ; Tue, 6 Dec 2022 09:53:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235581AbiLFJxp (ORCPT ); Tue, 6 Dec 2022 04:53:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235418AbiLFJvz (ORCPT ); Tue, 6 Dec 2022 04:51:55 -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 8C36E23BC5; Tue, 6 Dec 2022 01:51:09 -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 E359CB818E3; Tue, 6 Dec 2022 09:51:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 30F37C433C1; Tue, 6 Dec 2022 09:51:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1670320266; bh=OqXrkel/gqs5cVlkVunVtxkFHQXH2a23IGjNXD5nSpI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=T5ZMe/9QlZREU2UsUVObCC+9cMPh7m08dwqr+1zNIaV6sDQk1hx3E92N/9nMDhFNu KDYxsor+tV0TRZrRf0zH+wDiLdkKfj5VVM7ZKm+rjrfnHN7u7ULZAsHbCGKEeWRG2W BEJy71fgXwcSW1cTVa13KKD0Rx+uigtvFCQBx1VU+nXLfMijyQCXtVzD7XgyLQJkzK iTQCRn/zQrjCWmYrKMHU1iY67jRYUwAvfB24iS6bd8/DcJvmi7NCkGhQdOtXFFZegI /3AjwjnVIbkdrsWvLL8TX0bGLNn6A4/UjC40xdksSdwlxEWzg5I1i25ytbIOI01fNL A+/hzHR5FdROw== Date: Tue, 6 Dec 2022 11:51:02 +0200 From: Leon Romanovsky To: Jiasheng Jiang Cc: jesse.brandeburg@intel.com, anthony.l.nguyen@intel.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net] ice: Add check for kzalloc Message-ID: References: <20221206030805.15934-1-jiasheng@iscas.ac.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221206030805.15934-1-jiasheng@iscas.ac.cn> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 06, 2022 at 11:08:05AM +0800, Jiasheng Jiang wrote: > As kzalloc may fail and return NULL pointer, > it should be better to check the return value > in order to avoid the NULL pointer dereference. > > Fixes: d6b98c8d242a ("ice: add write functionality for GNSS TTY") > Signed-off-by: Jiasheng Jiang > --- > drivers/net/ethernet/intel/ice/ice_gnss.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) The idea is correct, but please change an implementation to use goto and proper unwind for whole function. It will remove duplication in the code which handles tty_port destroys. Thanks > > diff --git a/drivers/net/ethernet/intel/ice/ice_gnss.c b/drivers/net/ethernet/intel/ice/ice_gnss.c > index b5a7f246d230..6d3d5e75726b 100644 > --- a/drivers/net/ethernet/intel/ice/ice_gnss.c > +++ b/drivers/net/ethernet/intel/ice/ice_gnss.c > @@ -421,7 +421,7 @@ static struct tty_driver *ice_gnss_create_tty_driver(struct ice_pf *pf) > const int ICE_TTYDRV_NAME_MAX = 14; > struct tty_driver *tty_driver; > char *ttydrv_name; > - unsigned int i; > + unsigned int i, j; > int err; > > tty_driver = tty_alloc_driver(ICE_GNSS_TTY_MINOR_DEVICES, > @@ -462,6 +462,17 @@ static struct tty_driver *ice_gnss_create_tty_driver(struct ice_pf *pf) > GFP_KERNEL); > pf->gnss_serial[i] = NULL; > > + if (!pf->gnss_tty_port[i]) { > + for (j = 0; j < i; j++) { > + tty_port_destroy(pf->gnss_tty_port[j]); > + kfree(pf->gnss_tty_port[j]); > + } > + kfree(ttydrv_name); > + tty_driver_kref_put(pf->ice_gnss_tty_driver); > + > + return NULL; > + } > + > tty_port_init(pf->gnss_tty_port[i]); > tty_port_link_device(pf->gnss_tty_port[i], tty_driver, i); > } > -- > 2.25.1 >