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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 1BF17C43381 for ; Wed, 13 Mar 2019 19:34:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E581020693 for ; Wed, 13 Mar 2019 19:34:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552505656; bh=ehcFTpKlVQO+i83WcJUFAB9EgudEjTrngKna63Oxums=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=r3evX39YunGeNNWIaaOO8dCaGBqC4BW5Wl158fnbDUrcXLe5wZaJ8g2Oe77jXtpbg UpInfui6xz+LHcb99g0thfAaorCpAck08VdBbYUjxhsUxOwXEi894oGHjl2kOEeEx2 dsD+KvZmwjUxye6z4q0d9XNdKg4h/FWXIO2fjGTQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727789AbfCMTeO (ORCPT ); Wed, 13 Mar 2019 15:34:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:41196 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727107AbfCMTKh (ORCPT ); Wed, 13 Mar 2019 15:10:37 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EE08E2173C; Wed, 13 Mar 2019 19:10:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552504236; bh=ehcFTpKlVQO+i83WcJUFAB9EgudEjTrngKna63Oxums=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j+JcJ2jouQi8BHMQwpFivrsRk+qaKhB8Sk7W6bcr/sHyEgS+WtIPCz3WsXMHlgDht 8khvSjU57HNCF4pygii6BC8dkVK4daf1MWnMaEfgrmDwLIv/khsFIWPN+yEZhqM1Q7 60jip/fN3ZjyMQ/mfSVXQQyHzNlzUSShnoS+AGVg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Willem de Bruijn , Alexei Starovoitov , Sasha Levin Subject: [PATCH AUTOSEL 4.20 07/60] bpf: only adjust gso_size on bytestream protocols Date: Wed, 13 Mar 2019 15:09:28 -0400 Message-Id: <20190313191021.158171-7-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190313191021.158171-1-sashal@kernel.org> References: <20190313191021.158171-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Willem de Bruijn [ Upstream commit b90efd2258749e04e1b3f71ef0d716f2ac2337e0 ] bpf_skb_change_proto and bpf_skb_adjust_room change skb header length. For GSO packets they adjust gso_size to maintain the same MTU. The gso size can only be safely adjusted on bytestream protocols. Commit d02f51cbcf12 ("bpf: fix bpf_skb_adjust_net/bpf_skb_proto_xlat to deal with gso sctp skbs") excluded SKB_GSO_SCTP. Since then type SKB_GSO_UDP_L4 has been added, whose contents are one gso_size unit per datagram. Also exclude these. Move from a blacklist to a whitelist check to future proof against additional such new GSO types, e.g., for fraglist based GRO. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Signed-off-by: Willem de Bruijn Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- include/linux/skbuff.h | 6 ++++++ net/core/filter.c | 12 ++++-------- 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 8e63c166765e..875f56cbb756 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -4118,6 +4118,12 @@ static inline bool skb_is_gso_sctp(const struct sk_buff *skb) return skb_shinfo(skb)->gso_type & SKB_GSO_SCTP; } +static inline bool skb_is_gso_tcp(const struct sk_buff *skb) +{ + return skb_is_gso(skb) && + skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6); +} + static inline void skb_gso_reset(struct sk_buff *skb) { skb_shinfo(skb)->gso_size = 0; diff --git a/net/core/filter.c b/net/core/filter.c index 16350f8c8815..6e37c639519e 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2624,8 +2624,7 @@ static int bpf_skb_proto_4_to_6(struct sk_buff *skb) u32 off = skb_mac_header_len(skb); int ret; - /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ - if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) + if (!skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_cow(skb, len_diff); @@ -2666,8 +2665,7 @@ static int bpf_skb_proto_6_to_4(struct sk_buff *skb) u32 off = skb_mac_header_len(skb); int ret; - /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ - if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) + if (!skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_unclone(skb, GFP_ATOMIC); @@ -2792,8 +2790,7 @@ static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff) u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); int ret; - /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ - if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) + if (!skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_cow(skb, len_diff); @@ -2822,8 +2819,7 @@ static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff) u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); int ret; - /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ - if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) + if (!skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_unclone(skb, GFP_ATOMIC); -- 2.19.1