From patchwork Tue Nov 17 13:06:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 328104 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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 9D824C64E69 for ; Tue, 17 Nov 2020 13:52:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42E6B206A1 for ; Tue, 17 Nov 2020 13:52:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="iCro9oZG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731590AbgKQNwJ (ORCPT ); Tue, 17 Nov 2020 08:52:09 -0500 Received: from mail.kernel.org ([198.145.29.99]:37806 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731529AbgKQN3L (ORCPT ); Tue, 17 Nov 2020 08:29:11 -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 C6AFA20781; Tue, 17 Nov 2020 13:29:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605619750; bh=cu0zs86j7xIopRBr5gk/sqGY3Igq1piVnCLL7h2gk1Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iCro9oZGlWcLKLRyHPcXHq3ujOfF6YksUps9jrIPcyi/ZfdoB7sabtUs4OLmtSbgA RNmRUBvZX4cRP7zpIH+tVxmzS/jRna8eA0ppiEIpvfLkQ2DJvb5rml8JFkjkYVFSof k0xG3DyYpMjMW12nOVne01ietXyU9z5U2eINkbIw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jakub Kicinski , Heiner Kallweit Subject: [PATCH 5.4 144/151] r8169: fix potential skb double free in an error path Date: Tue, 17 Nov 2020 14:06:14 +0100 Message-Id: <20201117122128.431905207@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201117122121.381905960@linuxfoundation.org> References: <20201117122121.381905960@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 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: Greg Kroah-Hartman --- drivers/net/ethernet/realtek/r8169_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -5846,7 +5846,8 @@ static bool rtl8169_tso_csum_v2(struct r opts[1] |= transport_offset << TCPHO_SHIFT; } else { if (unlikely(rtl_test_hw_pad_bug(tp, skb))) - return !eth_skb_pad(skb); + /* eth_skb_pad would free the skb on error */ + return !__skb_put_padto(skb, ETH_ZLEN, false); } return true;