kernel/linux.git/net/ipv6/netfilter, branch master

netfilter: nat: use kfree_rcu to release ops

2026-04-20T21:45:41+00:00

Florian Westphal says: "Historically this is not an issue, even for normal base hooks: the data path doesn't use the original nf_hook_ops that are used to register the callbacks. However, in v5.14 I added the ability to dump the active netfilter hooks from userspace. This code will peek back into the nf_hook_ops that are available at the tail of the pointer-array blob used by the datapath. The nat hooks are special, because they are called indirectly from the central nat dispatcher hook. They are currently invisible to the nfnl hook dump subsystem though. But once that changes the nat ops structures have to be deferred too." Update nf_nat_register_fn() to deal with partial exposition of the hooks from error path which can be also an issue for nfnetlink_hook. Fixes: e2cf17d3774c ("netfilter: add new hook nfnl subsystem") Signed-off-by: Pablo Neira Ayuso

netfilter: require Ethernet MAC header before using eth_hdr()

2026-04-10T10:16:27+00:00

`ip6t_eui64`, `xt_mac`, the `bitmap:ip,mac`, `hash:ip,mac`, and `hash:mac` ipset types, and `nf_log_syslog` access `eth_hdr(skb)` after either assuming that the skb is associated with an Ethernet device or checking only that the `ETH_HLEN` bytes at `skb_mac_header(skb)` lie between `skb->head` and `skb->data`. Make these paths first verify that the skb is associated with an Ethernet device, that the MAC header was set, and that it spans at least a full Ethernet header before accessing `eth_hdr(skb)`. Suggested-by: Florian Westphal Tested-by: Ren Wei Signed-off-by: Zhengchuan Liang Signed-off-by: Ren Wei Signed-off-by: Florian Westphal

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

2026-04-09T20:20:59+00:00

Cross-merge networking fixes after downstream PR (net-7.0-rc8). Conflicts: net/ipv6/seg6_iptunnel.c c3812651b522f ("seg6: separate dst_cache for input and output paths in seg6 lwtunnel") 78723a62b969a ("seg6: add per-route tunnel source address") https://lore.kernel.org/adZhwtOYfo-0ImSa@sirena.org.uk net/ipv4/icmp.c fde29fd934932 ("ipv4: icmp: fix null-ptr-deref in icmp_build_probe()") d98adfbdd5c01 ("ipv4: drop ipv6_stub usage and use direct function calls") https://lore.kernel.org/adO3dccqnr6j-BL9@sirena.org.uk Adjacent changes: drivers/net/ethernet/stmicro/stmmac/chain_mode.c 51f4e090b9f8 ("net: stmmac: fix integer underflow in chain mode") 6b4286e05508 ("net: stmmac: rename STMMAC_GET_ENTRY() -> STMMAC_NEXT_ENTRY()") Signed-off-by: Jakub Kicinski

netfilter: ip6t_eui64: reject invalid MAC header for all packets

2026-04-08T11:33:56+00:00

`eui64_mt6()` derives a modified EUI-64 from the Ethernet source address and compares it with the low 64 bits of the IPv6 source address. The existing guard only rejects an invalid MAC header when `par->fragoff != 0`. For packets with `par->fragoff == 0`, `eui64_mt6()` can still reach `eth_hdr(skb)` even when the MAC header is not valid. Fix this by removing the `par->fragoff != 0` condition so that packets with an invalid MAC header are rejected before accessing `eth_hdr(skb)`. Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Reported-by: Yifan Wu Reported-by: Juefei Pu Co-developed-by: Yuan Tan Signed-off-by: Yuan Tan Suggested-by: Xin Liu Tested-by: Ren Wei Signed-off-by: Zhengchuan Liang Signed-off-by: Ren Wei Signed-off-by: Florian Westphal

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

2026-03-26T19:09:57+00:00

Cross-merge networking fixes after downstream PR (net-7.0-rc6). No conflicts, or adjacent changes. Signed-off-by: Jakub Kicinski

netfilter: ip6t_rt: reject oversized addrnr in rt_mt6_check()

2026-03-26T12:18:31+00:00

Reject rt match rules whose addrnr exceeds IP6T_RT_HOPS. rt_mt6() expects addrnr to stay within the bounds of rtinfo->addrs[]. Validate addrnr during rule installation so malformed rules are rejected before the match logic can use an out-of-range value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Yifan Wu Reported-by: Juefei Pu Co-developed-by: Yuan Tan Signed-off-by: Yuan Tan Suggested-by: Xin Liu Tested-by: Yuhang Zheng Signed-off-by: Ren Wei Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: nft_fib_ipv6: switch to fib6_lookup

2026-03-04T10:45:44+00:00

Existing code works but it requires a temporary dst object that is released again right away. Switch to fib6_lookup + RT6_LOOKUP_F_DST_NOREF: no need for temporary dst objects and refcount overhead anymore. Provides ~13% improvement in match performance. Signed-off-by: Florian Westphal

netfilter: nf_tables: remove register tracking infrastructure

2026-02-26T03:36:26+00:00

This facility was disabled in commit 9e539c5b6d9c ("netfilter: nf_tables: disable expression reduction infra"), because not all nft_exprs guarantee they will update the destination register: some may set NFT_BREAK instead to cancel evaluation of the rule. This has been dead code ever since. There are no plans to salvage this at this time, so remove this. Signed-off-by: Florian Westphal Link: https://patch.msgid.link/20260224205048.4718-10-fw@strlen.de Signed-off-by: Jakub Kicinski

netfilter: nf_reject: don't reply to icmp error messages

2025-09-11T13:40:55+00:00

tcp reject code won't reply to a tcp reset. But the icmp reject 'netdev' family versions will reply to icmp dst-unreach errors, unlike icmp_send() and icmp6_send() which are used by the inet family implementation (and internally by the REJECT target). Check for the icmp(6) type and do not respond if its an unreachable error. Without this, something like 'ip protocol icmp reject', when used in a netdev chain attached to 'lo', cause a packet loop. Same for two hosts that both use such a rule: each error packet will be replied to. Such situation persist until the (bogus) rule is amended to ratelimit or checks the icmp type before the reject statement. As the inet versions don't do this make the netdev ones follow along. Signed-off-by: Florian Westphal

netfilter: nf_reject: remove unneeded exports

2025-09-02T13:28:17+00:00

These functions have no external callers and can be static. Signed-off-by: Florian Westphal