FAILED: patch "[PATCH] macsec: Detect if Rx skb is macsec-related for offloading" failed to apply to 6.6-stable tree

gregkh
2024-04-29T11:59:26Z

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 642c984dd0e37dbaec9f87bd1211e5fac1f142bf
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024042923-sufferer-anywhere-76a7@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

642c984dd0e3 ("macsec: Detect if Rx skb is macsec-related for offloading devices that update md_dst")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 642c984dd0e37dbaec9f87bd1211e5fac1f142bf Mon Sep 17 00:00:00 2001
From: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Date: Tue, 23 Apr 2024 11:13:04 -0700
Subject: [PATCH] macsec: Detect if Rx skb is macsec-related for offloading
devices that update md_dst

Can now correctly identify where the packets should be delivered by using
md_dst or its absence on devices that provide it.

This detection is not possible without device drivers that update md_dst. A
fallback pattern should be used for supporting such device drivers. This
fallback mode causes multicast messages to be cloned to both the non-macsec
and macsec ports, independent of whether the multicast message received was
encrypted over MACsec or not. Other non-macsec traffic may also fail to be
handled correctly for devices in promiscuous mode.

Link: https://lore.kernel.org/netdev/ZULRxX9eIbFiVi7v@hog/
Cc: Sabrina Dubroca <sd@queasysnail.net>
Cc: stable@vger.kernel.org
Fixes: 860ead89b851 ("net/macsec: Add MACsec skb_metadata_dst Rx Data path support")
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Reviewed-by: Benjamin Poirier <bpoirier@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/20240423181319.115860-4-rrameshbabu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 0206b84284ab..ff016c11b4a0 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -999,10 +999,12 @@ static enum rx_handler_result handle_not_macsec(struct sk_buff *skb)
struct metadata_dst *md_dst;
struct macsec_rxh_data *rxd;
struct macsec_dev *macsec;
+ bool is_macsec_md_dst;

rcu_read_lock();
rxd = macsec_data_rcu(skb->dev);
md_dst = skb_metadata_dst(skb);
+ is_macsec_md_dst = md_dst && md_dst->type == METADATA_MACSEC;

list_for_each_entry_rcu(macsec, &rxd->secys, secys) {
struct sk_buff *nskb;
@@ -1013,14 +1015,42 @@ static enum rx_handler_result handle_not_macsec(struct sk_buff *skb)
* the SecTAG, so we have to deduce which port to deliver to.
*/
if (macsec_is_offloaded(macsec) && netif_running(ndev)) {
- struct macsec_rx_sc *rx_sc = NULL;
+ const struct macsec_ops *ops;

- if (md_dst && md_dst->type == METADATA_MACSEC)
- rx_sc = find_rx_sc(&macsec->secy, md_dst->u.macsec_info.sci);
+ ops = macsec_get_ops(macsec, NULL);

- if (md_dst && md_dst->type == METADATA_MACSEC && !rx_sc)
+ if (ops->rx_uses_md_dst && !is_macsec_md_dst)
continue;

+ if (is_macsec_md_dst) {
+ struct macsec_rx_sc *rx_sc;
+
+ /* All drivers that implement MACsec offload
+ * support using skb metadata destinations must
+ * indicate that they do so.
+ */
+ DEBUG_NET_WARN_ON_ONCE(!ops->rx_uses_md_dst);
+ rx_sc = find_rx_sc(&macsec->secy,
+ md_dst->u.macsec_info.sci);
+ if (!rx_sc)
+ continue;
+ /* device indicated macsec offload occurred */
+ skb->dev = ndev;
+ skb->pkt_type = PACKET_HOST;
+ eth_skb_pkt_type(skb, ndev);
+ ret = RX_HANDLER_ANOTHER;
+ goto out;
+ }
+
+ /* This datapath is insecure because it is unable to
+ * enforce isolation of broadcast/multicast traffic and
+ * unicast traffic with promiscuous mode on the macsec
+ * netdev. Since the core stack has no mechanism to
+ * check that the hardware did indeed receive MACsec
+ * traffic, it is possible that the response handling
+ * done by the MACsec port was to a plaintext packet.
+ * This violates the MACsec protocol standard.
+ */
if (ether_addr_equal_64bits(hdr->h_dest,
ndev->dev_addr)) {
/* exact match, divert skb to this port */
@@ -1036,14 +1066,10 @@ static enum rx_handler_result handle_not_macsec(struct sk_buff *skb)
break;

nskb->dev = ndev;
- if (ether_addr_equal_64bits(hdr->h_dest,
- ndev->broadcast))
- nskb->pkt_type = PACKET_BROADCAST;
- else
- nskb->pkt_type = PACKET_MULTICAST;
+ eth_skb_pkt_type(nskb, ndev);

__netif_rx(nskb);
- } else if (rx_sc || ndev->flags & IFF_PROMISC) {
+ } else if (ndev->flags & IFF_PROMISC) {
skb->dev = ndev;
skb->pkt_type = PACKET_HOST;
ret = RX_HANDLER_ANOTHER;