From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from codeconstruct.com.au (pi.codeconstruct.com.au [203.29.241.158]) (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 E6D8621421E for ; Wed, 25 Jun 2025 07:35:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.29.241.158 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750836908; cv=none; b=dLRELTDAJ08z5DegQnKcYbcZmRolxWXyDp+mUhj/RPFLvNdYbUr8KCghUY2XxfjqJyy2YWFPq8PH0iQ4DRcLZfB0kUJK9jVo00L9pmA5ogdqp0go0kxfNnKpqnmMms7ea9MfJtuE05Nlxwkd4UnelcI/TEvrNNKgnewX73VA08I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750836908; c=relaxed/simple; bh=a6aw4aa2cUbfhI+C1HpTVHxzU6H213PQb/EEj50UUX0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ljiSPSWbSESAvrxKQMPLaqmcZT0iEYSrXWu0KsRGFPTi9Wfpgk/smEpfS6zejV4bHUPbuif2s/DbInqnzxfgC5222GdfgihlaLA63wcGhDwYKNPTsME+IOffUqHf3+GlGdCmK8WZ4WBxiBS9TVB9a/lYv/iyfhD+u59MW0DzIic= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codeconstruct.com.au; spf=pass smtp.mailfrom=codeconstruct.com.au; dkim=pass (2048-bit key) header.d=codeconstruct.com.au header.i=@codeconstruct.com.au header.b=csWmUzFX; arc=none smtp.client-ip=203.29.241.158 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codeconstruct.com.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=codeconstruct.com.au Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=codeconstruct.com.au header.i=@codeconstruct.com.au header.b="csWmUzFX" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=codeconstruct.com.au; s=2022a; t=1750836904; bh=WbaZ851tPvl9z9qCq9g9hQhGeKab8Q7zy72SwZ1dqFQ=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=csWmUzFXRJSLeywLOIl3qAWBsW66gKjIrOBeZbrmVbQYx3KpO/yS9wsnRjjh+rGif 17UjRypDmhvAejGJWOH8GQHqPecfif2QouJZ9PwEiVsl5ScLu2KPGpr1xOnRtZUUYi 1JGQ/X5uQ4bTSVl4JyCqwWYnSciePD2AY0J5KqpCOJSiV3HCr1FDftZ718/NJzIY9d PiWhB6RhfI+PefvBZvw+1DX4FL3/fG+xKnsFSQtgrpj+yu8fiZ/97pHjPPwmfyHuw7 CQYORrnV6HA/kwz7PSV/siGUu9RB6Q1u3rnJ6/mjmrHZmcOBIJNtGrmt3c8BBJwBvq rC4c5RtMt3ufA== Received: by codeconstruct.com.au (Postfix, from userid 10000) id C36CB69A31; Wed, 25 Jun 2025 15:35:04 +0800 (AWST) From: Jeremy Kerr Date: Wed, 25 Jun 2025 15:34:39 +0800 Subject: [PATCH net-next v3 01/14] net: mctp: don't use source cb data when forwarding, ensure pkt_type is set Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20250625-dev-forwarding-v3-1-2061bd3013b3@codeconstruct.com.au> References: <20250625-dev-forwarding-v3-0-2061bd3013b3@codeconstruct.com.au> In-Reply-To: <20250625-dev-forwarding-v3-0-2061bd3013b3@codeconstruct.com.au> To: Matt Johnston , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman Cc: netdev@vger.kernel.org X-Mailer: b4 0.14.2 In the output path, only check the skb->cb data when we know it's from a local socket; input packets will have source address information there instead. In order to detect when we're forwarding, set skb->pkt_type on input/output. Signed-off-by: Jeremy Kerr --- net/mctp/route.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/net/mctp/route.c b/net/mctp/route.c index d9c8e5a5f9ce9aefbf16730c65a1f54caa5592b9..128ac46dda5eb882994960b8c0eb671007ad8583 100644 --- a/net/mctp/route.c +++ b/net/mctp/route.c @@ -392,6 +392,9 @@ static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb) */ skb_orphan(skb); + if (skb->pkt_type == PACKET_OUTGOING) + skb->pkt_type = PACKET_LOOPBACK; + /* ensure we have enough data for a header and a type */ if (skb->len < sizeof(struct mctp_hdr) + 1) goto out; @@ -578,7 +581,13 @@ static int mctp_route_output(struct mctp_route *route, struct sk_buff *skb) return -EMSGSIZE; } - if (cb->ifindex) { + /* If we're forwarding, we don't want to use the input path's cb, + * as it holds the *source* hardware addressing information. + * + * We will have a PACKET_HOST skb from the dev, or PACKET_OUTGOING + * from a socket; only use cb in the latter case. + */ + if (skb->pkt_type == PACKET_OUTGOING && cb->ifindex) { /* direct route; use the hwaddr we stashed in sendmsg */ if (cb->halen != skb->dev->addr_len) { /* sanity check, sendmsg should have already caught this */ @@ -587,6 +596,7 @@ static int mctp_route_output(struct mctp_route *route, struct sk_buff *skb) } daddr = cb->haddr; } else { + skb->pkt_type = PACKET_OUTGOING; /* If lookup fails let the device handle daddr==NULL */ if (mctp_neigh_lookup(route->dev, hdr->dest, daddr_buf) == 0) daddr = daddr_buf; @@ -1032,6 +1042,7 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, tag = req_tag & MCTP_TAG_MASK; } + skb->pkt_type = PACKET_OUTGOING; skb->protocol = htons(ETH_P_MCTP); skb->priority = 0; skb_reset_transport_header(skb); -- 2.39.5