kernel/linux.git/net/netfilter, branch v6.18.34

netfilter: nft_inner: release local_lock before re-enabling softirqs

2026-06-01T15:51:02+00:00

[ Upstream commit a6cb3ff979855f7f0ee9450a947fe8f96c2ba37a ] Quoting sashiko: In the error path, local_bh_enable() is called before local_unlock_nested_bh(). Fixes: ba36fada9ab4 ("netfilter: nft_inner: Use nested-BH locking for nft_pcpu_tun_ctx") Signed-off-by: Florian Westphal Reviewed-by: Fernando Fernandez Mancera Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin

netfilter: x_tables: add and use xtables_unregister_table_exit

2026-06-01T15:50:53+00:00

[ Upstream commit b4597d5fd7d2f8cebfffd40dffb5e003cc78964c ] Previous change added xtables_unregister_table_pre_exit to detach the table from the packetpath and to unlink it from the active table list. In case of rmmod, userspace that is doing set/getsockopt for this table will not be able to re-instantiate the table: 1. The larval table has been removed already 2. existing instantiated table is no longer on the xt pernet table list. This adds the second stage helper: unlink the table from the dying list, free the hook ops (if any) and do the audit notification. It replaces xt_unregister_table(). Fixes: fdacd57c79b7 ("netfilter: x_tables: never register tables by default") Reported-by: Tristan Madani Reviewed-by: Tristan Madani Closes: https://lore.kernel.org/netfilter-devel/20260429175613.1459342-1-tristmd@gmail.com/ Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin

netfilter: x_tables: add and use xt_unregister_table_pre_exit

2026-06-01T15:50:53+00:00

[ Upstream commit 527d6931473b75d90e38942aae6537d1a527f1fd ] Remove the copypasted variants of _pre_exit and add one single function in the xtables core. ebtables is not compatible with x_tables and therefore unchanged. This is a preparation patch to reduce noise in the followup bug fixes. Reviewed-by: Tristan Madani Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Stable-dep-of: b4597d5fd7d2 ("netfilter: x_tables: add and use xtables_unregister_table_exit") Signed-off-by: Sasha Levin

netfilter: nft_inner: Fix IPv6 inner_thoff desync

2026-06-01T15:50:43+00:00

commit b6a91f68ebfed9c38e0e9150f58a9b85da07181c upstream. In nft_inner_parse_l2l3(), when processing inner IPv6 packets, ipv6_find_hdr() correctly computes the transport header offset traversing all extension headers, but the result is immediately overwritten with nhoff + sizeof(_ip6h) (40 bytes), which only accounts for the IPv6 base header. This creates a desync between inner_thoff (wrong — points to extension header start) and l4proto (correct — e.g., IPPROTO_TCP), enabling transport header forgery and potential firewall bypass. This issue affects stable versions from Linux 6.2. For comparison, the normal (non-inner) IPv6 path correctly preserves ipv6_find_hdr()'s result. Removing the incorrect overwrite ensures that ipv6_find_hdr()'s calculated transport header offset is preserved, thereby fixing the desynchronization. Fixes: 3a07327d10a0 ("netfilter: nft_inner: support for inner tunnel header matching") Cc: stable@vger.kernel.org Reported-by: Yizhou Zhao Reported-by: Yuxiang Yang Reported-by: Xuewei Feng Reported-by: Qi Li Reported-by: Ke Xu Assisted-by: GLM:5.1 Z.ai Signed-off-by: Yizhou Zhao Reviewed-by: Fernando Fernandez Mancera Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: ipset: stop hash:* range iteration at end

2026-06-01T15:50:42+00:00

commit 0d3a282ab5f165fc207ff49ea5b6ad8f54616bd6 upstream. The following hash set variants: hash:ip,mark hash:ip,port hash:ip,port,ip hash:ip,port,net iterate IPv4 ranges with a 32-bit iterator. The iterator must stop once the last address in the requested range has been processed. Advancing it once more can move the traversal state past the end of the request, so a later retry may continue from an unintended position. Handle the iterator increment explicitly at the end of the loop and stop once the upper bound has been processed. This keeps the existing retry behaviour intact for valid ranges while preventing traversal from continuing past the original boundary. Fixes: 48596a8ddc46 ("netfilter: ipset: Fix adding an IPv4 range containing more than 2^31 addresses") Cc: stable@kernel.org Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Signed-off-by: Nan Li Signed-off-by: Ren Wei Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: nf_queue: hold bridge skb->dev while queued

2026-06-01T15:50:42+00:00

commit e196115ec330a18de415bdb9f5071aa9f08e53ce upstream. br_pass_frame_up() rewrites skb->dev from the ingress port to the bridge master before queueing bridge LOCAL_IN packets. NFQUEUE only holds references on state.in/out and bridge physdevs, so a queued bridge packet can retain a freed bridge master in skb->dev until reinjection. When the verdict is reinjected later, br_netif_receive_skb() re-enters the receive path with skb->dev still pointing at the freed bridge master, triggering a use-after-free. Store skb->dev in the queue entry, hold a reference on it for the queue lifetime, and use the saved device when dropping queued packets during NETDEV_DOWN handling. Fixes: ac2863445686 ("netfilter: bridge: add nf_afinfo to enable queuing to userspace") Cc: stable@kernel.org Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Signed-off-by: Haoze Xie Signed-off-by: Ren Wei Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: nft_ct: fix missing expect put in obj eval

2026-05-23T11:07:16+00:00

commit 19f94b6fee75b3ef7fbc06f3745b9a771a8a19a4 upstream. nft_ct_expect_obj_eval() allocates an expectation and may call nf_ct_expect_related(), but never drops its local reference. Add nf_ct_expect_put(exp) before return to balance allocation. Fixes: 857b46027d6f ("netfilter: nft_ct: add ct expectations support") Cc: stable@vger.kernel.org Signed-off-by: Li Xiasong Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: nf_conntrack_sip: get helper before allocating expectation

2026-05-23T11:07:15+00:00

commit eb6317739b1ea3ab28791e1f91b24781905fa815 upstream. process_register_request() allocates an expectation and then checks whether a conntrack helper is available. If helper lookup fails, the function returns early and the allocated expectation is left behind. Reorder the code to fetch and validate helper before calling nf_ct_expect_alloc(). This keeps the logic simpler and removes the leak path while preserving existing behavior. Fixes: e14575fa7529 ("netfilter: nf_conntrack: use rcu accessors where needed") Cc: stable@vger.kernel.org Signed-off-by: Li Xiasong Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: skip recording stale or retransmitted INIT

2026-05-23T11:07:11+00:00

[ Upstream commit 576a5d2bad4814c881a829576b1261b9b8159d2b ] An INIT whose init_tag matches the peer's vtag does not provide new state information. It indicates either: - a stale INIT (after INIT-ACK has already been seen on the same side), or - a retransmitted INIT (after INIT has already been recorded on the same side). In both cases, the INIT must not update ct->proto.sctp.init[] state, since it does not advance the handshake tracking and may otherwise corrupt INIT/INIT-ACK validation logic. Allow INIT processing only when the conntrack entry is newly created (SCTP_CONNTRACK_NONE), or when the init_tag differs from the stored peer vtag. Note it skips the check for the ct with old_state SCTP_CONNTRACK_NONE in nf_conntrack_sctp_packet(), as it is just created in sctp_new() where it set ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = ih->init_tag. Fixes: 9fb9cbb1082d ("[NETFILTER]: Add nf_conntrack subsystem.") Signed-off-by: Xin Long Reviewed-by: Marcelo Ricardo Leitner Acked-by: Florian Westphal Link: https://patch.msgid.link/ee56c3e416452b2a40589a2a85245ac2ad5e9f4b.1777214801.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

netfilter: nf_conntrack_sip: don't use simple_strtoul

2026-05-23T11:07:07+00:00

[ Upstream commit 8cf6809cddcbe301aedfc6b51bcd4944d45795f6 ] Replace unsafe port parsing in epaddr_len(), ct_sip_parse_header_uri(), and ct_sip_parse_request() with a new sip_parse_port() helper that validates each digit against the buffer limit, eliminating the use of simple_strtoul() which assumes NUL-terminated strings. The previous code dereferenced pointers without bounds checks after sip_parse_addr() and relied on simple_strtoul() on non-NUL-terminated skb data. A port that reaches the buffer limit without a trailing character is also rejected as malformed. Also get rid of all simple_strtoul() usage in conntrack, prefer a stricter version instead. There are intentional changes: - Bail out if number is > UINT_MAX and indicate a failure, same for too long sequences. While we do accept 05535 as port 5535, we will not accept e.g. 'sip:10.0.0.1:005060'. While its syntactically valid under RFC 3261, we should restrict this to not waste cycles when presented with malformed packets with 64k '0' characters. - Force base 10 in ct_sip_parse_numerical_param(). This is used to fetch 'expire=' and 'rports='; both are expected to use base-10. - In nf_nat_sip.c, only accept the parsed value if its within the 1k-64k range. - epaddr_len now returns 0 if the port is invalid, as it already does for invalid ip addresses. This is intentional. nf_conntrack_sip performs lots of guesswork to find the right parts of the message to parse. Being stricter could break existing setups. Connection tracking helpers are designed to allow traffic to pass, not to block it. Based on an earlier patch from Jenny Guanni Qu . Fixes: 05e3ced297fe ("[NETFILTER]: nf_conntrack_sip: introduce SIP-URI parsing helper") Reported-by: Klaudia Kloc Reported-by: Dawid Moczadło Reported-by: Jenny Guanni Qu . Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin