From patchwork Wed Apr 10 09:52:19 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Asbj=C3=B8rn_Sloth_T=C3=B8nnesen?= X-Patchwork-Id: 13624011 X-Patchwork-Delegate: kuba@kernel.org Received: from mail1.fiberby.net (mail1.fiberby.net [193.104.135.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9690C125CD; Wed, 10 Apr 2024 09:52:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.104.135.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712742765; cv=none; b=F41aGtnBoNNs8/MwMw9Jw7nvo25myuy9A9EQ/QK/gFopeQ6HN9Giouuyl8QzpCMCE+gnaieVYfbN3GQ6fcJHCiEZB5/eJYBgCZ59RteoJsNXVuAffrbHJ4ZmLYwU9xJwPQszCQsR07GioXu5vOrSAMJX9/6WeYm6bOpSYT8oG2M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712742765; c=relaxed/simple; bh=A4SQWAoLTl1trJBjvVe+szcFLe+EAdNIB9cPeBqzuDg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=N0BpGlzZgOclQ1iwbJxoURzf1mao4x6FLURtENQjiurcza8E6EkzNF5SektU2qFWG5zWrYOpKWq5iCiOfrGbYj+T8plETQM1dxj/6woykSWmZw9U5SG3EU0IbDo0anTdJm1Z3xiJ1o10h3PJFWDGM5B8T2pDEA6/zlJaj1d5ePU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fiberby.net; spf=pass smtp.mailfrom=fiberby.net; dkim=pass (2048-bit key) header.d=fiberby.net header.i=@fiberby.net header.b=eI0+fOVg; arc=none smtp.client-ip=193.104.135.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fiberby.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fiberby.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=fiberby.net header.i=@fiberby.net header.b="eI0+fOVg" Received: from x201s (193-104-135-243.ip4.fiberby.net [193.104.135.243]) by mail1.fiberby.net (Postfix) with ESMTPSA id 73943600A2; Wed, 10 Apr 2024 09:52:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=fiberby.net; s=202008; t=1712742759; bh=A4SQWAoLTl1trJBjvVe+szcFLe+EAdNIB9cPeBqzuDg=; h=From:To:Cc:Subject:Date:From; b=eI0+fOVggcZc7WNQ/m1KCUdUH7wDPdHE1nD+kVl0KFnmjjE1LqJu62Xs4yCV4pTAf Ktnn5KdaxmdtwIABs0VRdvn3DLMlWRmw2JUvXErX8QRxVw8DFGwpNS3jn9YEHCWYqP XFJDD+ql//6KIeIuLWaeeso92NXpxHebXuEgAz//Q5v9ha/6+beKebk+aFw+RR1Ak+ qzJBLrl2jkSt6juOf3cJprOHbtj6zwBmE9Awia+mWN9BcLoFK1YLsyIiPuPqwVAmbE s40KOtKJQrflr+9qyt6nv7+J7kbLmkvwiDW3V8NR7Iwi0cy2UMqMuxx0p//wugJAk9 avsXySNcW876A== Received: by x201s (Postfix, from userid 1000) id A78D5200D78; Wed, 10 Apr 2024 09:52:33 +0000 (UTC) From: =?utf-8?q?Asbj=C3=B8rn_Sloth_T=C3=B8nnesen?= To: netdev@vger.kernel.org Cc: =?utf-8?q?Asbj=C3=B8rn_Sloth_T=C3=B8nnesen?= , Steen Hegelund , Lars Povlsen , Daniel Machon , UNGLinuxDriver@microchip.com, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-kernel@vger.kernel.org Subject: [PATCH net v2] net: sparx5: flower: fix fragment flags handling Date: Wed, 10 Apr 2024 09:52:19 +0000 Message-ID: <20240410095224.6372-1-ast@fiberby.net> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org I noticed that only 3 out of the 4 input bits were used, mt.key->flags & FLOW_DIS_IS_FRAGMENT was never checked. In order to avoid a complicated maze, I converted it to use a 16 byte mapping table. As shown in the table below the old heuristics doesn't always do the right thing, ie. when FLOW_DIS_IS_FRAGMENT=1/1 then it used to only match follow-up fragment packets. Here are all the combinations, and their resulting new/old VCAP key/mask filter: /- FLOW_DIS_IS_FRAGMENT (key/mask) | /- FLOW_DIS_FIRST_FRAG (key/mask) | | /-- new VCAP fragment (key/mask) v v v v- old VCAP fragment (key/mask) 0/0 0/0 -/- -/- impossible (due to entry cond. on mask) 0/0 0/1 -/- 0/3 !! invalid (can't match non-fragment + follow-up frag) 0/0 1/0 -/- -/- impossible (key > mask) 0/0 1/1 1/3 1/3 first fragment 0/1 0/0 0/3 3/3 !! not fragmented 0/1 0/1 0/3 3/3 !! not fragmented (+ not first fragment) 0/1 1/0 -/- -/- impossible (key > mask) 0/1 1/1 -/- 1/3 !! invalid (non-fragment and first frag) 1/0 0/0 -/- -/- impossible (key > mask) 1/0 0/1 -/- -/- impossible (key > mask) 1/0 1/0 -/- -/- impossible (key > mask) 1/0 1/1 -/- -/- impossible (key > mask) 1/1 0/0 1/1 3/3 !! some fragment 1/1 0/1 3/3 3/3 follow-up fragment 1/1 1/0 -/- -/- impossible (key > mask) 1/1 1/1 1/3 1/3 first fragment In the datasheet the VCAP fragment values are documented as: 0 = no fragment 1 = initial fragment 2 = suspicious fragment 3 = valid follow-up fragment Result: 3 combinations match the old behavior, 3 combinations have been corrected, 2 combinations are now invalid, and fail, 8 combinations are impossible. It should now be aligned with how FLOW_DIS_IS_FRAGMENT and FLOW_DIS_FIRST_FRAG is set in __skb_flow_dissect() in net/core/flow_dissector.c Since the VCAP fragment values are not a bitfield, we have to ignore the suspicious fragment value, eg. when matching on any kind of fragment with FLOW_DIS_IS_FRAGMENT=1/1. Only compile tested, and logic tested in userspace, as I unfortunately don't have access to this switch chip (yet). v2: - Improved in-line documentation of mapping table (requested by Steen) - Relocated enum and mapping table (requested by Steen) - Added Reviewed-by from Steen Hegelund - Added Tested-by from Daniel Machon v1: https://lore.kernel.org/netdev/20240408172738.96447-1-ast@fiberby.net/ Fixes: d6c2964db3fe ("net: microchip: sparx5: Adding more tc flower keys for the IS2 VCAP") Signed-off-by: Asbjørn Sloth Tønnesen Reviewed-by: Steen Hegelund Tested-by: Daniel Machon Reviewed-by: Jacob Keller --- .../microchip/sparx5/sparx5_tc_flower.c | 61 ++++++++++++------- 1 file changed, 40 insertions(+), 21 deletions(-) diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c b/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c index 523e0c470894f..f986850efdcc7 100644 --- a/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c +++ b/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c @@ -36,6 +36,27 @@ struct sparx5_tc_flower_template { u16 l3_proto; /* protocol specified in the template */ }; +/* SparX-5 VCAP fragment types: + * 0 = no fragment, 1 = initial fragment, + * 2 = suspicious fragment, 3 = valid follow-up fragment + */ +enum { /* key / mask */ + FRAG_NOT = 0x03, /* 0 / 3 */ + FRAG_SOME = 0x11, /* 1 / 1 */ + FRAG_FIRST = 0x13, /* 1 / 3 */ + FRAG_LATER = 0x33, /* 3 / 3 */ + FRAG_INVAL = 0xff, /* invalid */ +}; + +/* Flower fragment flag to VCAP fragment type mapping */ +static const u8 sparx5_vcap_frag_map[4][4] = { /* is_frag */ + { FRAG_INVAL, FRAG_INVAL, FRAG_INVAL, FRAG_FIRST }, /* 0/0 */ + { FRAG_NOT, FRAG_NOT, FRAG_INVAL, FRAG_INVAL }, /* 0/1 */ + { FRAG_INVAL, FRAG_INVAL, FRAG_INVAL, FRAG_INVAL }, /* 1/0 */ + { FRAG_SOME, FRAG_LATER, FRAG_INVAL, FRAG_FIRST } /* 1/1 */ + /* 0/0 0/1 1/0 1/1 <-- first_frag */ +}; + static int sparx5_tc_flower_es0_tpid(struct vcap_tc_flower_parse_usage *st) { @@ -145,29 +166,27 @@ sparx5_tc_flower_handler_control_usage(struct vcap_tc_flower_parse_usage *st) flow_rule_match_control(st->frule, &mt); if (mt.mask->flags) { - if (mt.mask->flags & FLOW_DIS_FIRST_FRAG) { - if (mt.key->flags & FLOW_DIS_FIRST_FRAG) { - value = 1; /* initial fragment */ - mask = 0x3; - } else { - if (mt.mask->flags & FLOW_DIS_IS_FRAGMENT) { - value = 3; /* follow up fragment */ - mask = 0x3; - } else { - value = 0; /* no fragment */ - mask = 0x3; - } - } - } else { - if (mt.mask->flags & FLOW_DIS_IS_FRAGMENT) { - value = 3; /* follow up fragment */ - mask = 0x3; - } else { - value = 0; /* no fragment */ - mask = 0x3; - } + u8 is_frag_key = !!(mt.key->flags & FLOW_DIS_IS_FRAGMENT); + u8 is_frag_mask = !!(mt.mask->flags & FLOW_DIS_IS_FRAGMENT); + u8 is_frag_idx = (is_frag_key << 1) | is_frag_mask; + + u8 first_frag_key = !!(mt.key->flags & FLOW_DIS_FIRST_FRAG); + u8 first_frag_mask = !!(mt.mask->flags & FLOW_DIS_FIRST_FRAG); + u8 first_frag_idx = (first_frag_key << 1) | first_frag_mask; + + /* lookup verdict based on the 2 + 2 input bits */ + u8 vdt = sparx5_vcap_frag_map[is_frag_idx][first_frag_idx]; + + if (vdt == FRAG_INVAL) { + NL_SET_ERR_MSG_MOD(st->fco->common.extack, + "match on invalid fragment flag combination"); + return -EINVAL; } + /* extract VCAP fragment key and mask from verdict */ + value = (vdt >> 4) & 0x3; + mask = vdt & 0x3; + err = vcap_rule_add_key_u32(st->vrule, VCAP_KF_L3_FRAGMENT_TYPE, value, mask);