kernel/linux.git/net/ipv4/xfrm4_input.c, branch linux-7.1.y

xfrm: hold dev ref until after transport_finish NF_HOOK

2026-04-07T08:12:40+00:00

After async crypto completes, xfrm_input_resume() calls dev_put() immediately on re-entry before the skb reaches transport_finish. The skb->dev pointer is then used inside NF_HOOK and its okfn, which can race with device teardown. Remove the dev_put from the async resumption entry and instead drop the reference after the NF_HOOK call in transport_finish, using a saved device pointer since NF_HOOK may consume the skb. This covers NF_DROP, NF_QUEUE and NF_STOLEN paths that skip the okfn. For non-transport exits (decaps, gro, drop) and secondary async return points, release the reference inline when async is set. Suggested-by: Florian Westphal Fixes: acf568ee859f ("xfrm: Reinject transport-mode packets through tasklet") Cc: stable@vger.kernel.org Signed-off-by: Qi Tang Signed-off-by: Steffen Klassert

xfrm: Set transport header to fix UDP GRO handling

2025-07-02T07:19:56+00:00

The referenced commit replaced a call to __xfrm4|6_udp_encap_rcv() with a custom check for non-ESP markers. But what the called function also did was setting the transport header to the ESP header. The function that follows, esp4|6_gro_receive(), relies on that being set when it calls xfrm_parse_spi(). We have to set the full offset as the skb's head was not moved yet so adding just the UDP header length won't work. Fixes: e3fd05777685 ("xfrm: Fix UDP GRO handling for some corner cases") Signed-off-by: Tobias Brunner Signed-off-by: Steffen Klassert

xfrm: Fix UDP GRO handling for some corner cases

2025-04-17T09:08:16+00:00

This fixes an issue that's caused if there is a mismatch between the data offset in the GRO header and the length fields in the regular sk_buff due to the pskb_pull()/skb_push() calls. That's because the UDP GRO layer stripped off the UDP header via skb_gro_pull() already while the UDP header was explicitly not pulled/pushed in this function. For example, an IKE packet that triggered this had len=data_len=1268 and the data_offset in the GRO header was 28 (IPv4 + UDP). So pskb_pull() was called with an offset of 28-8=20, which reduced len to 1248 and via pskb_may_pull() and __pskb_pull_tail() it also set data_len to 1248. As the ESP offload module was not loaded, the function bailed out and called skb_push(), which restored len to 1268, however, data_len remained at 1248. So while skb_headlen() was 0 before, it was now 20. The latter caused a difference of 8 instead of 28 (or 0 if pskb_pull()/skb_push() was called with the complete GRO data_offset) in gro_try_pull_from_frag0() that triggered a call to gro_pull_from_frag0() that corrupted the packet. This change uses a more GRO-like approach seen in other GRO receivers via skb_gro_header() to just read the actual data we are interested in and does not try to "restore" the UDP header at this point to call the existing function. If the offload module is not loaded, it immediately bails out, otherwise, it only does a quick check to see if the packet is an IKE or keepalive packet instead of calling the existing function. Fixes: 172bf009c18d ("xfrm: Support GRO for IPv4 ESP in UDP encapsulation") Fixes: 221ddb723d90 ("xfrm: Support GRO for IPv6 ESP in UDP encapsulation") Signed-off-by: Tobias Brunner Signed-off-by: Steffen Klassert

ipv4: Convert ip_route_input_noref() to dscp_t.

2024-10-03T23:21:21+00:00

Pass a dscp_t variable to ip_route_input_noref(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Callers of ip_route_input_noref() to consider are: * arp_process() in net/ipv4/arp.c. This function sets the tos parameter to 0, which is already a valid dscp_t value, so it doesn't need to be adjusted for the new prototype. * ip_route_input(), which already has a dscp_t variable to pass as parameter. We just need to remove the inet_dscp_to_dsfield() conversion. * ipvlan_l3_rcv(), bpf_lwt_input_reroute(), ip_expire(), ip_rcv_finish_core(), xfrm4_rcv_encap_finish() and xfrm4_rcv_encap(), which get the DSCP directly from IPv4 headers and can simply use the ip4h_dscp() helper. While there, declare the IPv4 header pointers as const in ipvlan_l3_rcv() and bpf_lwt_input_reroute(). Also, modify the declaration of ip_route_input_noref() in include/net/route.h so that it matches the prototype of its implementation in net/ipv4/route.c. Signed-off-by: Guillaume Nault Reviewed-by: David Ahern Link: https://patch.msgid.link/a8a747bed452519c4d0cc06af32c7e7795d7b627.1727807926.git.gnault@redhat.com Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2024-05-09T17:01:01+00:00

Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c 35d92abfbad8 ("net: hns3: fix kernel crash when devlink reload during initialization") 2a1a1a7b5fd7 ("net: hns3: add command queue trace for hns3") Signed-off-by: Jakub Kicinski

xfrm: Preserve vlan tags for transport mode software GRO

2024-04-26T04:44:33+00:00

The software GRO path for esp transport mode uses skb_mac_header_rebuild prior to re-injecting the packet via the xfrm_napi_dev. This only copies skb->mac_len bytes of header which may not be sufficient if the packet contains 802.1Q tags or other VLAN tags. Worse copying only the initial header will leave a packet marked as being VLAN tagged but without the corresponding tag leading to mangling when it is later untagged. The VLAN tags are important when receiving the decrypted esp transport mode packet after GRO processing to ensure it is received on the correct interface. Therefore record the full mac header length in xfrm*_transport_input for later use in corresponding xfrm*_transport_finish to copy the entire mac header when rebuilding the mac header for GRO. The skb->data pointer is left pointing skb->mac_header bytes after the start of the mac header as is expected by the network stack and network and transport header offsets reset to this location. Fixes: 7785bba299a8 ("esp: Add a software GRO codepath") Signed-off-by: Paul Davey Signed-off-by: Steffen Klassert

udpencap: Remove Obsolete UDP_ENCAP_ESPINUDP_NON_IKE Support

2024-04-18T09:38:23+00:00

The UDP_ENCAP_ESPINUDP_NON_IKE mode, introduced into the Linux kernel in 2004 [2], has remained inactive and obsolete for an extended period. This mode was originally defined in an early version of an IETF draft [1] from 2001. By the time it was integrated into the kernel in 2004 [2], it had already been replaced by UDP_ENCAP_ESPINUDP [3] in later versions of draft-ietf-ipsec-udp-encaps, particularly in version 06. Over time, UDP_ENCAP_ESPINUDP_NON_IKE has lost its relevance, with no known use cases. With this commit, we remove support for UDP_ENCAP_ESPINUDP_NON_IKE, simplifying the codebase and eliminating unnecessary complexity. Kernel will return an error -ENOPROTOOPT if the userspace tries to set this option. References: [1] https://datatracker.ietf.org/doc/html/draft-ietf-ipsec-udp-encaps-00.txt [2] Commit that added UDP_ENCAP_ESPINUDP_NON_IKE to the Linux historic repository. Author: Andreas Gruenbacher Date: Fri Apr 9 01:47:47 2004 -0700 [IPSEC]: Support draft-ietf-ipsec-udp-encaps-00/01, some ipec impls need it. [3] Commit that added UDP_ENCAP_ESPINUDP to the Linux historic repository. Author: Derek Atkins Date: Wed Apr 2 13:21:02 2003 -0800 [IPSEC]: Implement UDP Encapsulation framework. Signed-off-by: Antony Antony Signed-off-by: Steffen Klassert

net: adopt skb_network_offset() and similar helpers

2024-03-04T08:47:06+00:00

This is a cleanup patch, making code a bit more concise. 1) Use skb_network_offset(skb) in place of (skb_network_header(skb) - skb->data) 2) Use -skb_network_offset(skb) in place of (skb->data - skb_network_header(skb)) 3) Use skb_transport_offset(skb) in place of (skb_transport_header(skb) - skb->data) 4) Use skb_inner_transport_offset(skb) in place of (skb_inner_transport_header(skb) - skb->data) Signed-off-by: Eric Dumazet Acked-by: Edward Cree # for sfc Signed-off-by: David S. Miller

xfrm Fix use after free in __xfrm6_udp_encap_rcv.

2023-10-23T05:10:39+00:00

A recent patch changed xfrm6_udp_encap_rcv to not free the skb itself anymore but fogot the case where xfrm4_udp_encap_rcv is called subsequently. Fix this by moving the call to xfrm4_udp_encap_rcv from __xfrm6_udp_encap_rcv to xfrm6_udp_encap_rcv. Fixes: 221ddb723d90 ("xfrm: Support GRO for IPv6 ESP in UDP encapsulation") Signed-off-by: Steffen Klassert

xfrm: Support GRO for IPv4 ESP in UDP encapsulation

2023-10-06T05:30:40+00:00

This patch enables the GRO codepath for IPv4 ESP in UDP encapsulated packets. Decapsulation happens at L2 and saves a full round through the stack for each packet. This is also needed to support HW offload for ESP in UDP encapsulation. Enabling this would imporove performance for ESP in UDP datapath, i.e IPsec with NAT in between. By default GRP for ESP-in-UDP is disabled for UDP sockets. To enable this feature for an ESP socket, the following two options need to be set: 1. enable ESP-in-UDP: (this is already set by an IKE daemon). int type = UDP_ENCAP_ESPINUDP; setsockopt(fd, SOL_UDP, UDP_ENCAP, &type, sizeof(type)); 2. To enable GRO for ESP in UDP socket: type = true; setsockopt(fd, SOL_UDP, UDP_GRO, &type, sizeof(type)); Enabling ESP-in-UDP has the side effect of preventing the Linux stack from seeing ESP packets at the L3 (when ESP OFFLOAD is disabled), as packets are immediately decapsulated from UDP and decrypted. This change may affect nftable rules that match on ESP packets at L3. Also tcpdump won't see the ESP packet. Developers/admins are advised to review and adapt any nftable rules accordingly before enabling this feature to prevent potential rule breakage. Also tcpdump will not see from ESP packets from a ESP in UDP flow, when this is enabled. Signed-off-by: Steffen Klassert Co-developed-by: Antony Antony Signed-off-by: Antony Antony Reviewed-by: Eyal Birger