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=-6.8 required=3.0 tests=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 C7A9FC433E0 for ; Mon, 1 Jun 2020 18:17:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9F72E206E2 for ; Mon, 1 Jun 2020 18:17:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591035421; bh=dUG1Ak5XxgkCPUsPDSxotQhuzW0jzCC4BzCrfzxmx3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rObOQLdpZ5cEvq0zkRY+f1j6IGct5bm+BPWxEUyfX6bPkGKWvO47CTKBAVaCWItdn Rn/+2N4ah+9yRr1xtpL8nfhhiBPFXIyhZ5J1njnJ7QQmmvAyBaHwv/QXc6Us0ukC7u 0KTilOgN+bHxVkicRt18XpRT/3p31Vm410C/Hbhk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731774AbgFASRB (ORCPT ); Mon, 1 Jun 2020 14:17:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:37792 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731754AbgFASQx (ORCPT ); Mon, 1 Jun 2020 14:16:53 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 9B20320776; Mon, 1 Jun 2020 18:16:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591035413; bh=dUG1Ak5XxgkCPUsPDSxotQhuzW0jzCC4BzCrfzxmx3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1FeVC21IZ7b3JG7/wmC5uP++ktry5KYazoN4QgVSYD2xVLeR54shV/qfq1GgUiWhr l+SjvFDIeMROgaK2FaEWKtkfeNdBn+zam23KkKzx/kBtuW6FZffaWIrZMR3xnriuRT tEbFW/WlfSqBiHXJN+Xz2usCj7mdP9x4G5n6UKPE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiumei Mu , Xin Long , Steffen Klassert Subject: [PATCH 5.6 148/177] xfrm: call xfrm_output_gso when inner_protocol is set in xfrm_output Date: Mon, 1 Jun 2020 19:54:46 +0200 Message-Id: <20200601174100.780862436@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601174048.468952319@linuxfoundation.org> References: <20200601174048.468952319@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xin Long commit a204aef9fd77dce1efd9066ca4e44eede99cd858 upstream. An use-after-free crash can be triggered when sending big packets over vxlan over esp with esp offload enabled: [] BUG: KASAN: use-after-free in ipv6_gso_pull_exthdrs.part.8+0x32c/0x4e0 [] Call Trace: [] dump_stack+0x75/0xa0 [] kasan_report+0x37/0x50 [] ipv6_gso_pull_exthdrs.part.8+0x32c/0x4e0 [] ipv6_gso_segment+0x2c8/0x13c0 [] skb_mac_gso_segment+0x1cb/0x420 [] skb_udp_tunnel_segment+0x6b5/0x1c90 [] inet_gso_segment+0x440/0x1380 [] skb_mac_gso_segment+0x1cb/0x420 [] esp4_gso_segment+0xae8/0x1709 [esp4_offload] [] inet_gso_segment+0x440/0x1380 [] skb_mac_gso_segment+0x1cb/0x420 [] __skb_gso_segment+0x2d7/0x5f0 [] validate_xmit_skb+0x527/0xb10 [] __dev_queue_xmit+0x10f8/0x2320 <--- [] ip_finish_output2+0xa2e/0x1b50 [] ip_output+0x1a8/0x2f0 [] xfrm_output_resume+0x110e/0x15f0 [] __xfrm4_output+0xe1/0x1b0 [] xfrm4_output+0xa0/0x200 [] iptunnel_xmit+0x5a7/0x920 [] vxlan_xmit_one+0x1658/0x37a0 [vxlan] [] vxlan_xmit+0x5e4/0x3ec8 [vxlan] [] dev_hard_start_xmit+0x125/0x540 [] __dev_queue_xmit+0x17bd/0x2320 <--- [] ip6_finish_output2+0xb20/0x1b80 [] ip6_output+0x1b3/0x390 [] ip6_xmit+0xb82/0x17e0 [] inet6_csk_xmit+0x225/0x3d0 [] __tcp_transmit_skb+0x1763/0x3520 [] tcp_write_xmit+0xd64/0x5fe0 [] __tcp_push_pending_frames+0x8c/0x320 [] tcp_sendmsg_locked+0x2245/0x3500 [] tcp_sendmsg+0x27/0x40 As on the tx path of vxlan over esp, skb->inner_network_header would be set on vxlan_xmit() and xfrm4_tunnel_encap_add(), and the later one can overwrite the former one. It causes skb_udp_tunnel_segment() to use a wrong skb->inner_network_header, then the issue occurs. This patch is to fix it by calling xfrm_output_gso() instead when the inner_protocol is set, in which gso_segment of inner_protocol will be done first. While at it, also improve some code around. Fixes: 7862b4058b9f ("esp: Add gso handlers for esp4 and esp6") Reported-by: Xiumei Mu Signed-off-by: Xin Long Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/xfrm_output.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/net/xfrm/xfrm_output.c +++ b/net/xfrm/xfrm_output.c @@ -583,18 +583,20 @@ int xfrm_output(struct sock *sk, struct xfrm_state_hold(x); if (skb_is_gso(skb)) { - skb_shinfo(skb)->gso_type |= SKB_GSO_ESP; + if (skb->inner_protocol) + return xfrm_output_gso(net, sk, skb); - return xfrm_output2(net, sk, skb); + skb_shinfo(skb)->gso_type |= SKB_GSO_ESP; + goto out; } if (x->xso.dev && x->xso.dev->features & NETIF_F_HW_ESP_TX_CSUM) goto out; + } else { + if (skb_is_gso(skb)) + return xfrm_output_gso(net, sk, skb); } - if (skb_is_gso(skb)) - return xfrm_output_gso(net, sk, skb); - if (skb->ip_summed == CHECKSUM_PARTIAL) { err = skb_checksum_help(skb); if (err) {