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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 7F583C64E7C for ; Tue, 17 Nov 2020 13:37:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 217D1207BC for ; Tue, 17 Nov 2020 13:37:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="qWMJeBa9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732354AbgKQNhK (ORCPT ); Tue, 17 Nov 2020 08:37:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:48270 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732315AbgKQNhI (ORCPT ); Tue, 17 Nov 2020 08:37:08 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DF30920870; Tue, 17 Nov 2020 13:37:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605620228; bh=H0dIFFMoiuOw6flSrUg0/ibVcmqoAPx4AYA+UHLxcHg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qWMJeBa9OHwuBETH78D5tBDgpvL/Ck4COMfmL4l+z/rhLOCOSof3IAFH1LAwuiFfc Wyav2DiBS54WN9VMHdTqfsYG9lvH+7lqLzhOy8rzQAFEdqSXINdPdOZsMzXV2NHInc CvJAoRlRND2IiJE5BmiFiln9yxJsaH+kVwBh0big= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jakub Kicinski , Heiner Kallweit , Sasha Levin Subject: [PATCH 5.9 148/255] r8169: fix potential skb double free in an error path Date: Tue, 17 Nov 2020 14:04:48 +0100 Message-Id: <20201117122146.167423295@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201117122138.925150709@linuxfoundation.org> References: <20201117122138.925150709@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Heiner Kallweit [ Upstream commit cc6528bc9a0c901c83b8220a2e2617f3354d6dd9 ] The caller of rtl8169_tso_csum_v2() frees the skb if false is returned. eth_skb_pad() internally frees the skb on error what would result in a double free. Therefore use __skb_put_padto() directly and instruct it to not free the skb on error. Fixes: b423e9ae49d7 ("r8169: fix offloaded tx checksum for small packets.") Reported-by: Jakub Kicinski Signed-off-by: Heiner Kallweit Link: https://lore.kernel.org/r/f7e68191-acff-9ded-4263-c016428a8762@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/realtek/r8169_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index c74d9c02a805f..ed918c12bc5e9 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -4145,7 +4145,8 @@ static bool rtl8169_tso_csum_v2(struct rtl8169_private *tp, opts[1] |= transport_offset << TCPHO_SHIFT; } else { if (unlikely(skb->len < ETH_ZLEN && rtl_test_hw_pad_bug(tp))) - return !eth_skb_pad(skb); + /* eth_skb_pad would free the skb on error */ + return !__skb_put_padto(skb, ETH_ZLEN, false); } return true; -- 2.27.0