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 6C937C4332F for ; Wed, 16 Nov 2022 16:21:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232801AbiKPQV3 (ORCPT ); Wed, 16 Nov 2022 11:21:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58176 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231448AbiKPQVX (ORCPT ); Wed, 16 Nov 2022 11:21:23 -0500 Received: from mail-pg1-x530.google.com (mail-pg1-x530.google.com [IPv6:2607:f8b0:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BFD94387A; Wed, 16 Nov 2022 08:21:22 -0800 (PST) Received: by mail-pg1-x530.google.com with SMTP id q71so17114933pgq.8; Wed, 16 Nov 2022 08:21:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:from:to:cc:subject :date:message-id:reply-to; bh=c559sc2jOhM0vrBcTp9Mpp0NMui8sZVfjdQCJ/lgLP8=; b=ELi91KjiC5QJN0McvzHtVelOHgF8KVqnx+G22rwjbtuLT2bJRZrBYdmEE4CRnniwKW RFRDbYP51foLBaMP2lNMVm2gt33fmhkfNvFxBQ4m04jH4djWBwh1dir079gK182+AQSS QUWE5eTXarA6po+3aZeBIE/LJYeZCzvr54o16gS+r3ZkIGRP0prfgh7LAcwprL4RIHTO bYzU1q8q59RH0+HwisesW/rJQq8UPiskCWVV1J+3b4VC5fjy/d46i1PjM2blQpduOouw 3HbOyKxWGlRoAIpeyf0LPiK5prXE/Cp64pqT7sWqry/xZGeIjK6Ujykxh9er5vqhFMaP iddQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=c559sc2jOhM0vrBcTp9Mpp0NMui8sZVfjdQCJ/lgLP8=; b=MJZ/jJ6aCl92j8QIaN1MQmIvtZlKulNI4gIFlA11v0tENI+O+e+A2goYWE0p2HJQ/b V600pK3NYMzSTbWEe9wiDf3PjTrGH/RbvWzsVt75oaUwcc1c9nEApu4eADAr6UdZKyS2 a7/Uv4ljYYgJdO/sa4dGHr6FdUT54O4Kpe4IFzdtGytPe3mYOexSOxkH4n4B3BLDvoP0 6vy7nhN7RCryGcqfNxmvhCt/67xZZk7PBeVgtqD/JjfxKn2+ZS7ZWdoBxLewbEOFAncW YsPnKDMSQmNdwpCDKfZX3Df0vg84ZCes2JN1IdV8NVl2ix/zW/mq3NK7rTtKLCf9RLGa sJ8w== X-Gm-Message-State: ANoB5pmU2juHSGOZU3CAKef71wM6QtvfM5hwjRWfVjTDIUWCpyJ6QswP PuTXyrnOM38ly0avPTTe1Cw= X-Google-Smtp-Source: AA0mqf6Ze6pBOTTvGO4TdaAkZUDd5JW5CUaETCWrQYTounopPw69P87KMjSZiFiun7zfH2CzuifGyw== X-Received: by 2002:a62:3382:0:b0:572:6da6:de57 with SMTP id z124-20020a623382000000b005726da6de57mr8778589pfz.30.1668615681399; Wed, 16 Nov 2022 08:21:21 -0800 (PST) Received: from [192.168.0.128] ([98.97.119.47]) by smtp.googlemail.com with ESMTPSA id c5-20020a634e05000000b0046f7e1ca434sm9914272pgb.0.2022.11.16.08.21.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Nov 2022 08:21:20 -0800 (PST) Message-ID: Subject: Re: [PATCH net] e100: Fix possible use after free in e100_xmit_prepare From: Alexander H Duyck To: Wang Hai , jesse.brandeburg@intel.com, anthony.l.nguyen@intel.com, baijiaju1990@163.com, jeffrey.t.kirsher@intel.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org Date: Wed, 16 Nov 2022 08:21:19 -0800 In-Reply-To: <20221115172407.72863-1-wanghai38@huawei.com> References: <20221115172407.72863-1-wanghai38@huawei.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.44.4 (3.44.4-2.fc36) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2022-11-16 at 01:24 +0800, Wang Hai wrote: > In e100_xmit_prepare(), if we can't map the skb, then return -ENOMEM, so > e100_xmit_frame() will return NETDEV_TX_BUSY and the upper layer will > resend the skb. But the skb is already freed, which will cause UAF bug > when the upper layer resends the skb. >=20 > Remove the harmful free. >=20 > Fixes: 5e5d49422dfb ("e100: Release skb when DMA mapping is failed in e10= 0_xmit_prepare") > Signed-off-by: Wang Hai > --- > drivers/net/ethernet/intel/e100.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) >=20 > diff --git a/drivers/net/ethernet/intel/e100.c b/drivers/net/ethernet/int= el/e100.c > index 560d1d442232..d3fdc290937f 100644 > --- a/drivers/net/ethernet/intel/e100.c > +++ b/drivers/net/ethernet/intel/e100.c > @@ -1741,11 +1741,8 @@ static int e100_xmit_prepare(struct nic *nic, stru= ct cb *cb, > dma_addr =3D dma_map_single(&nic->pdev->dev, skb->data, skb->len, > DMA_TO_DEVICE); > /* If we can't map the skb, have the upper layer try later */ > - if (dma_mapping_error(&nic->pdev->dev, dma_addr)) { > - dev_kfree_skb_any(skb); > - skb =3D NULL; > + if (dma_mapping_error(&nic->pdev->dev, dma_addr)) > return -ENOMEM; > - } > =20 > /* > * Use the last 4 bytes of the SKB payload packet as the CRC, used for I'm surprised the original patch that this essentially reverts was even accepted. Reviewed-by: Alexander Duyck