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=-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=unavailable 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 80412C64E75 for ; Tue, 17 Nov 2020 13:16:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19FA52151B for ; Tue, 17 Nov 2020 13:16:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="gSelzmst" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729605AbgKQNP7 (ORCPT ); Tue, 17 Nov 2020 08:15:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:47440 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730245AbgKQNPw (ORCPT ); Tue, 17 Nov 2020 08:15:52 -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 919542225B; Tue, 17 Nov 2020 13:15:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605618952; bh=h5VWCUOtijWFwdnCAgQlgw+aocOp9uhPcWoUd1h7kP4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gSelzmst5hox4dPzgaZBftgrbWgTBNGGZaSITBcdBqp2CofatBs2GcsPPa7ntvlyz PhNKBbkWTbbVesWxr89vcSYWxzzmxmuO/7QjoGkTGIpWE1HGa1w574dMWYMmtxJMpu QMZklgxcwjwN7vv6+pjC+inW5aC/DjK1Oi8gjKX8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jakub Kicinski , Heiner Kallweit Subject: [PATCH 4.14 62/85] r8169: fix potential skb double free in an error path Date: Tue, 17 Nov 2020 14:05:31 +0100 Message-Id: <20201117122114.082163959@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201117122111.018425544@linuxfoundation.org> References: <20201117122111.018425544@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: linux-kernel@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.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/realtek/r8169.c +++ b/drivers/net/ethernet/realtek/r8169.c @@ -7143,7 +7143,8 @@ 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;