6.16-stable review patch. If anyone has any objections, please let me know.
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From: Sabrina Dubroca sd@queasysnail.net
[ Upstream commit 91d8a53db2199eefc73ecf3682e0665ea6895696 ]
Xiumei reported a regression in IPsec offload tests over xfrmi, where the traffic for IPv6 over IPv4 tunnels is processed in SW instead of going through crypto offload, after commit cc18f482e8b6 ("xfrm: provide common xdo_dev_offload_ok callback implementation").
Commit cc18f482e8b6 added a generic version of existing checks attempting to prevent packets with IPv4 options or IPv6 extension headers from being sent to HW that doesn't support offloading such packets. The check mistakenly uses x->props.family (the outer family) to determine the inner packet's family and verify if options/extensions are present.
In the case of IPv6 over IPv4, the check compares some of the traffic class bits to the expected no-options ihl value (5). The original check was introduced in commit 2ac9cfe78223 ("net/mlx5e: IPSec, Add Innova IPSec offload TX data path"), and then duplicated in the other drivers. Before commit cc18f482e8b6, the loose check (ihl > 5) passed because those traffic class bits were not set to a value that triggered the no-offload codepath. Packets with options/extension headers that should have been handled in SW went through the offload path, and were likely dropped by the NIC or incorrectly processed. Since commit cc18f482e8b6, the check is now strict (ihl != 5), and in a basic setup (no traffic class configured), all packets go through the no-offload codepath.
The commits that introduced the incorrect family checks in each driver are: 2ac9cfe78223 ("net/mlx5e: IPSec, Add Innova IPSec offload TX data path") 8362ea16f69f ("crypto: chcr - ESN for Inline IPSec Tx") 859a497fe80c ("nfp: implement xfrm callbacks and expose ipsec offload feature to upper layer") 32188be805d0 ("cn10k-ipsec: Allow ipsec crypto offload for skb with SA") [ixgbe/ixgbevf commits are ignored, as that HW does not support tunnel mode, thus no cross-family setups are possible]
Fixes: cc18f482e8b6 ("xfrm: provide common xdo_dev_offload_ok callback implementation") Reported-by: Xiumei Mu xmu@redhat.com Signed-off-by: Sabrina Dubroca sd@queasysnail.net Reviewed-by: Leon Romanovsky leonro@nvidia.com Reviewed-by: Zhu Yanjun yanjun.zhu@linux.dev Signed-off-by: Steffen Klassert steffen.klassert@secunet.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/xfrm/xfrm_device.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c index c7a1f080d2de3..44b9de6e4e778 100644 --- a/net/xfrm/xfrm_device.c +++ b/net/xfrm/xfrm_device.c @@ -438,7 +438,7 @@ bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
check_tunnel_size = x->xso.type == XFRM_DEV_OFFLOAD_PACKET && x->props.mode == XFRM_MODE_TUNNEL; - switch (x->props.family) { + switch (x->inner_mode.family) { case AF_INET: /* Check for IPv4 options */ if (ip_hdr(skb)->ihl != 5)