wireguard-linux/net/ipv6, branch devel

ipv6: mld: rename mldv2_mrc() and add mldv2_qqi()

2026-05-05T02:09:41Z

Rename mldv2_mrc() to mldv2_mrd() as it is used to calculate the Maximum Response Delay from the Maximum Response Code. Introduce a new API mldv2_qqi() to define the existing calculation logic of QQI from QQIC. This also organizes the existing mld_update_qi() API. Reviewed-by: Nikolay Aleksandrov Reviewed-by: Ido Schimmel Signed-off-by: Ujjal Roy Link: https://patch.msgid.link/20260502131907.987-3-royujjal@gmail.com Signed-off-by: Jakub Kicinski

ip6mr: plug drop_reason to ip6mr_cache_report()

2026-05-02T00:02:45Z

- Check mrt->mroute_sk earlier in the function. - Use sock_queue_rcv_skb_reason() instead of sock_queue_rcv_skb(). - Use sk_skb_reason_drop() instead of kfree_skb(). Note that we return -ENOMEM if sock_queue_rcv_skb_reason() failed, as the precise error is not really needed for callers. - Remove one net_warn_ratelimited(). Signed-off-by: Eric Dumazet Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/20260430074004.4133602-1-edumazet@google.com Signed-off-by: Jakub Kicinski

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

2026-04-30T19:51:05Z

Cross-merge networking fixes after downstream PR (net-7.1-rc2). No conflicts, or adjacent changes. Signed-off-by: Jakub Kicinski

net/tcp-ao: Return void from functions that can no longer fail

2026-04-30T07:38:56Z

Since tcp-ao now uses the crypto library API instead of crypto_ahash, and MACs and keys now have a statically-known maximum size, many tcp-ao functions can no longer fail. Propagate this change up into the return types of various functions. Reviewed-by: Ard Biesheuvel Signed-off-by: Eric Biggers Link: https://patch.msgid.link/20260427172727.9310-5-ebiggers@kernel.org Signed-off-by: Paolo Abeni

net/tcp-ao: Use stack-allocated MAC and traffic_key buffers

2026-04-30T07:38:56Z

Now that the maximum MAC and traffic key lengths are statically-known small values, allocate MACs and traffic keys on the stack instead of with kmalloc. This eliminates multiple failure-prone GFP_ATOMIC allocations. Note that some cases such as tcp_ao_prepare_reset() are left unchanged for now since they would require slightly wider changes. Reviewed-by: Ard Biesheuvel Signed-off-by: Eric Biggers Link: https://patch.msgid.link/20260427172727.9310-4-ebiggers@kernel.org Signed-off-by: Paolo Abeni

net/tcp-ao: Use crypto library API instead of crypto_ahash

2026-04-30T07:38:56Z

Currently the kernel's TCP-AO implementation does the MAC and KDF computations using the crypto_ahash API. This API is inefficient and difficult to use, and it has required extensive workarounds in the form of per-CPU preallocated objects (tcp_sigpool) to work at all. Let's use lib/crypto/ instead. This means switching to straightforward stack-allocated structures, virtually addressed buffers, and direct function calls. It also means removing quite a bit of error handling. This makes TCP-AO quite a bit faster. This also enables many additional cleanups, which later commits will handle: removing tcp-sigpool, removing support for crypto_tfm cloning, removing more error handling, and replacing more dynamically-allocated buffers with stack buffers based on the now-statically-known limits. Reviewed-by: Ard Biesheuvel Signed-off-by: Eric Biggers Link: https://patch.msgid.link/20260427172727.9310-3-ebiggers@kernel.org Signed-off-by: Paolo Abeni

net: ipv6: fix NOREF dst use in seg6 and rpl lwtunnels

2026-04-28T09:16:14Z

seg6_input_core() and rpl_input() call ip6_route_input() which sets a NOREF dst on the skb, then pass it to dst_cache_set_ip6() invoking dst_hold() unconditionally. On PREEMPT_RT, ksoftirqd is preemptible and a higher-priority task can release the underlying pcpu_rt between the lookup and the caching through a concurrent FIB lookup on a shared nexthop. Simplified race sequence: ksoftirqd/X higher-prio task (same CPU X) ----------- -------------------------------- seg6_input_core(,skb)/rpl_input(skb) dst_cache_get() -> miss ip6_route_input(skb) -> ip6_pol_route(,skb,flags) [RT6_LOOKUP_F_DST_NOREF in flags] -> FIB lookup resolves fib6_nh [nhid=N route] -> rt6_make_pcpu_route() [creates pcpu_rt, refcount=1] pcpu_rt->sernum = fib6_sernum [fib6_sernum=W] -> cmpxchg(fib6_nh.rt6i_pcpu, NULL, pcpu_rt) [slot was empty, store succeeds] -> skb_dst_set_noref(skb, dst) [dst is pcpu_rt, refcount still 1] rt_genid_bump_ipv6() -> bumps fib6_sernum [fib6_sernum from W to Z] ip6_route_output() -> ip6_pol_route() -> FIB lookup resolves fib6_nh [nhid=N] -> rt6_get_pcpu_route() pcpu_rt->sernum != fib6_sernum [W <> Z, stale] -> prev = xchg(rt6i_pcpu, NULL) -> dst_release(prev) [prev is pcpu_rt, refcount 1->0, dead] dst = skb_dst(skb) [dst is the dead pcpu_rt] dst_cache_set_ip6(dst) -> dst_hold() on dead dst -> WARN / use-after-free For the race to occur, ksoftirqd must be preemptible (PREEMPT_RT without PREEMPT_RT_NEEDS_BH_LOCK) and a concurrent task must be able to release the pcpu_rt. Shared nexthop objects provide such a path, as two routes pointing to the same nhid share the same fib6_nh and its rt6i_pcpu entry. Fix seg6_input_core() and rpl_input() by calling skb_dst_force() after ip6_route_input() to force the NOREF dst into a refcounted one before caching. The output path is not affected as ip6_route_output() already returns a refcounted dst. Fixes: af4a2209b134 ("ipv6: sr: use dst_cache in seg6_input") Fixes: a7a29f9c361f ("net: ipv6: add rpl sr tunnel") Cc: stable@vger.kernel.org Signed-off-by: Andrea Mayer Reviewed-by: Simon Horman Reviewed-by: Justin Iurman Link: https://patch.msgid.link/20260421094735.20997-1-andrea.mayer@uniroma2.it Signed-off-by: Paolo Abeni

ipv6: rpl: reserve mac_len headroom when recompressed SRH grows

2026-04-28T00:47:26Z

ipv6_rpl_srh_rcv() decompresses an RFC 6554 Source Routing Header, swaps the next segment into ipv6_hdr->daddr, recompresses, then pulls the old header and pushes the new one plus the IPv6 header back. The recompressed header can be larger than the received one when the swap reduces the common-prefix length the segments share with daddr (CmprI=0, CmprE>0, seg[0][0] != daddr[0] gives the maximum +8 bytes). pskb_expand_head() was gated on segments_left == 0, so on earlier segments the push consumed unchecked headroom. Once skb_push() leaves fewer than skb->mac_len bytes in front of data, skb_mac_header_rebuild()'s call to: skb_set_mac_header(skb, -skb->mac_len); will store (data - head) - mac_len into the u16 mac_header field, which wraps to ~65530, and the following memmove() writes mac_len bytes ~64KiB past skb->head. A single AF_INET6/SOCK_RAW/IPV6_HDRINCL packet over lo with a two segment type-3 SRH (CmprI=0, CmprE=15) reaches headroom 8 after one pass; KASAN reports a 14-byte OOB write in ipv6_rthdr_rcv. Fix this by expanding the head whenever the remaining room is less than the push size plus mac_len, and request that much extra so the rebuilt MAC header fits afterwards. Fixes: 8610c7c6e3bd ("net: ipv6: add support for rpl sr exthdr") Cc: stable Reported-by: Anthropic Signed-off-by: Greg Kroah-Hartman Link: https://patch.msgid.link/2026042133-gout-unvented-1bd9@gregkh Signed-off-by: Jakub Kicinski

ipv6: Cap TLV scan in ip6_tnl_parse_tlv_enc_lim

2026-04-23T18:52:07Z

Commit 47d3d7ac656a ("ipv6: Implement limits on Hop-by-Hop and Destination options") added net.ipv6.max_{hbh,dst}_opts_{cnt,len} and applied them in ip6_parse_tlv(), the generic TLV walker invoked from ipv6_destopt_rcv() and ipv6_parse_hopopts(). ip6_tnl_parse_tlv_enc_lim() does not go through ip6_parse_tlv(); it has its own hand-rolled TLV scanner inside its NEXTHDR_DEST branch which looks for IPV6_TLV_TNL_ENCAP_LIMIT. That inner loop is bounded only by optlen, which can be up to 2048 bytes. Stuffing the Destination Options header with 2046 Pad1 (type=0) entries advances the scanner a single byte at a time, yielding ~2000 TLV iterations per extension header. Reusing max_dst_opts_cnt to bound the TLV iterations, matching the semantics from 47d3d7ac656a, would require duplicating ip6_parse_tlv() to also validate Pad1/PadN payload. It would also mandate enforcing max_dst_opts_len, since otherwise an attacker shifts the axis to few options with a giant PadN and recovers the original DoS. Allowing up to 8 options before the tunnel encapsulation limit TLV is liberal enough; in practice encap limit is the first TLV. Thus, go with a hard-coded limit IP6_TUNNEL_MAX_DEST_TLVS (8). Signed-off-by: Daniel Borkmann Reviewed-by: Ido Schimmel Reviewed-by: Justin Iurman Signed-off-by: Jakub Kicinski

Merge tag 'nf-26-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf

2026-04-23T09:20:38Z

Pablo Neira Ayuso says: ==================== Netfilter/IPVS fixes for net The following batch contains Netfilter/IPVS fixes for net: 1) nft_osf actually only supports IPv4, restrict it. 2) Address possible division by zero in nfnetlink_osf, from Xiang Mei. 3) Remove unsafe use of sprintf to fix possible buffer overflow in the SIP NAT helper, from Florian Westphal. 4) Restrict xt_mac, xt_owner and xt_physdev to inet families only; xt_realm is only for ipv4, otherwise null-pointer-deref is possible. 5) Use kfree_rcu() in nat core to release hooks, this can be an issue once nfnetlink_hook gets support to dump NAT hook information, not currently a real issue but better fix it now. From Florian Westphal. 6) Fix MTU checks in IPVS, from Yingnan Zhang. 7) Fix possible out-of-bounds when matching TCP options in nfnetlink_osf, from Fernando Fernandez Mancera. 8) Fix potential nul-ptr-deref in ttl check in nfnetlink_osf, remove useless loop to fix this, also from Fernando. This is a smaller batch, there are more patches pending in the queue to arm another pull request as soon as this is considered good enough. AI might complain again about one more issue regarding osf and big-endian arches in osf but this batch is targetting crash fixes for osf at this stage. netfilter pull request 26-04-20 * tag 'nf-26-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nfnetlink_osf: fix potential NULL dereference in ttl check netfilter: nfnetlink_osf: fix out-of-bounds read on option matching ipvs: fix MTU check for GSO packets in tunnel mode netfilter: nat: use kfree_rcu to release ops netfilter: xtables: restrict several matches to inet family netfilter: conntrack: remove sprintf usage netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO netfilter: nft_osf: restrict it to ipv4 ==================== Link: https://patch.msgid.link/20260420220215.111510-1-pablo@netfilter.org Signed-off-by: Paolo Abeni