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 674B7C4332F for ; Thu, 17 Nov 2022 13:05:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239425AbiKQNFg (ORCPT ); Thu, 17 Nov 2022 08:05:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57246 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231634AbiKQNFe (ORCPT ); Thu, 17 Nov 2022 08:05:34 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A5D2668680; Thu, 17 Nov 2022 05:05:33 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 453FD61DC8; Thu, 17 Nov 2022 13:05:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CF665C433C1; Thu, 17 Nov 2022 13:05:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1668690332; bh=ZBEVfZF0QfQVnHQWHX5dlMjl2pKu1VG+I2bBas101IA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dpDWeSb5XkVrG8JHsAMvnoA9fhp2c6yoZ3FwJtqXYxbiCSKfWgmKGanNImUWBDVw/ IBllnoICpbAQl2ErpTx0t1Mole0ubfTgTcmq+4XU5gjhLpt1hZO7oOHm3BSPhJKKTx +H6J1bfg5WJK54MCbGNpRdAS2HdA0Qi/D1ajMVx1+iTajXK7pQKvkxsULCoaaaWNSU wps/PM2FZBtzhJ7O8ZfoMmLT6mYe728drxe+3iZdr/7U3+NWVlEyZ3dGgBUQFolQ+T ewkVSRvZdWCyXojC3QwAuIJo/sw4ElrXonvM2V2W6f1GvijlfKWp4VyA7jmFLE10en j+E0340KFrZpA== Date: Thu, 17 Nov 2022 15:05:27 +0200 From: Leon Romanovsky To: Zhang Changzhong Cc: Edward Cree , Martin Habets , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net] sfc: fix potential memleak in __ef100_hard_start_xmit() Message-ID: References: <1668671409-10909-1-git-send-email-zhangchangzhong@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Nov 17, 2022 at 08:41:52PM +0800, Zhang Changzhong wrote: > > > On 2022/11/17 19:36, Leon Romanovsky wrote: > > On Thu, Nov 17, 2022 at 03:50:09PM +0800, Zhang Changzhong wrote: > >> The __ef100_hard_start_xmit() returns NETDEV_TX_OK without freeing skb > >> in error handling case, add dev_kfree_skb_any() to fix it. > >> > >> Fixes: 51b35a454efd ("sfc: skeleton EF100 PF driver") > >> Signed-off-by: Zhang Changzhong > >> --- > >> drivers/net/ethernet/sfc/ef100_netdev.c | 1 + > >> 1 file changed, 1 insertion(+) > >> > >> diff --git a/drivers/net/ethernet/sfc/ef100_netdev.c b/drivers/net/ethernet/sfc/ef100_netdev.c > >> index 88fa295..ddcc325 100644 > >> --- a/drivers/net/ethernet/sfc/ef100_netdev.c > >> +++ b/drivers/net/ethernet/sfc/ef100_netdev.c > >> @@ -218,6 +218,7 @@ netdev_tx_t __ef100_hard_start_xmit(struct sk_buff *skb, > >> skb->len, skb->data_len, channel->channel); > >> if (!efx->n_channels || !efx->n_tx_channels || !channel) { > >> netif_stop_queue(net_dev); > >> + dev_kfree_skb_any(skb); > >> goto err; > >> } > > > > ef100 doesn't release in __ef100_enqueue_skb() either. SKB shouldn't be > > NULL or ERR at this stage. > > SKB shouldn't be NULL or ERR, so it can be freed. But this code looks weird. Please take a look __ef100_enqueue_skb() and see if it frees SKB on error or not. If not, please fix it. Thanks > > > > > diff --git a/drivers/net/ethernet/sfc/ef100_tx.c b/drivers/net/ethernet/sfc/ef100_tx.c > > index 29ffaf35559d..426706b91d02 100644 > > --- a/drivers/net/ethernet/sfc/ef100_tx.c > > +++ b/drivers/net/ethernet/sfc/ef100_tx.c > > @@ -497,7 +497,7 @@ int __ef100_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb, > > > > err: > > efx_enqueue_unwind(tx_queue, old_insert_count); > > - if (!IS_ERR_OR_NULL(skb)) > > + if (rc) > > dev_kfree_skb_any(skb); > > > > /* If we're not expecting another transmit and we had something to push > > > > > >> > >> -- > >> 2.9.5 > >> > > . > >