This is a note to let you know that I've just added the patch titled xfrm: Linearize the skb after offloading if needed. to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xfrm-linearize-the-skb-after-offloading-if-needed.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 1a0e295f5becf9f21c0381f77f6e5f097b2f4fed Author: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Date: Wed Jun 14 12:02:02 2023 +0200 xfrm: Linearize the skb after offloading if needed. [ Upstream commit f015b900bc3285322029b4a7d132d6aeb0e51857 ] With offloading enabled, esp_xmit() gets invoked very late, from within validate_xmit_xfrm() which is after validate_xmit_skb() validates and linearizes the skb if the underlying device does not support fragments. esp_output_tail() may add a fragment to the skb while adding the auth tag/ IV. Devices without the proper support will then send skb->data points to with the correct length so the packet will have garbage at the end. A pcap sniffer will claim that the proper data has been sent since it parses the skb properly. It is not affected with INET_ESP_OFFLOAD disabled. Linearize the skb after offloading if the sending hardware requires it. It was tested on v4, v6 has been adopted. Fixes: 7785bba299a8d ("esp: Add a software GRO codepath") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Signed-off-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c index 8c0af30fb0679..5cd219d7e7466 100644 --- a/net/ipv4/esp4_offload.c +++ b/net/ipv4/esp4_offload.c @@ -283,6 +283,9 @@ static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_ secpath_reset(skb); + if (skb_needs_linearize(skb, skb->dev->features) && + __skb_linearize(skb)) + return -ENOMEM; return 0; } diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c index 1c532638b2adf..e19c1844276f8 100644 --- a/net/ipv6/esp6_offload.c +++ b/net/ipv6/esp6_offload.c @@ -314,6 +314,9 @@ static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features secpath_reset(skb); + if (skb_needs_linearize(skb, skb->dev->features) && + __skb_linearize(skb)) + return -ENOMEM; return 0; }