Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net. This batches fixes for real crashes with trivial/correctness fixes. There is too a rework of the conntrack expectation timeout strategy to deal with a possible race when removing an expectation. 1) Fix the incorrect flowtable timeout extension for entries in hw offload, from Adrian Bente. This is correcting a defect in the functionality, no crash. 2) Hold reference to device under the fake dst in br_netfilter, from Haoze Xie. This is fixing a possible UaF if the device is removed while packet is sitting in nfqueue. 3) Reject template conntrack in xt_cluster, otherwise access to uninitialize conntrack fields are possible leading to WARN_ON due to unset layer 3 protocol. From Wyatt Feng. 4) Make sure the IPv6 tunnel header is in the linear skb data area before pulling. While at it remove incomplete NEXTHDR_DEST support. From Lorenzo Bianconi. This possibly leading to crash if IPv4 header is not in the linear area. 5) Use test_bit_acquire in ipset hash set to avoid reordering of subsequent memory access. This is addressing a LLM related report, no crash has been observed. From Jozsef Kadlecsik. 6) Use test_bit_acquire in ipset bitmap set too, for the same reason as in the previous patch, from Jozsef Kadlecsik. 7) Call kfree_rcu() after rcu_assign_pointer() to address a possible UaF if kfree_rcu() runs inmediately, which to my understanding never happens. Never observed in practise, reported by LLM. Also from Jozsef Kadlecsik. 8) Use disable_delayed_work_sync() instead cancel_delayed_work_sync() to avoid that ipset GC handler re-queues work as reported by LLM. From Jozsef Kadlecsik. This is for correctness. 9) Restore the check in nft_payload for exceeding payloda offset over 2^16. From Florian Westphal. This fixes a silent truncation, not a big deal, but better be assertive and reject it. 10) Validate NFT_META_BRI_IIFHWADDR can only run from bridge prerouting. From Florian Westphal. Harmless but it could allow to read bytes from skb->cb. 11) Zero out destination hardware address during the flowtable path setup, also from Florian. This is a correctness fix, LLM points that possible infoleak can happen but topology to achieve it is not clear. 12) Skip IPv4 options if present when building the IPV4 reject reply. Otherwise bytes in the IPv4 options header can be sent back to origin where the ICMP header is being expected. Again from Florian Westphal. 13) Replace timer API for expectation by GC worker approach. This is implicitly fixing a race between nf_ct_remove_expectations() which might fail to remove the expectation due to timer_del() returning false because timer has expired and callback is being run concurrently. This fix is addressing a crash that has been already reported with a reproducer. 14) Check if br_vlan_get_pvid_rcu() fails, otherwise possible stack infoleak of 4-bytes. From Florian Westphal. * tag 'nf-26-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nft_meta_bridge: fix NFT_META_BRI_IIFPVID stack leak netfilter: nf_conntrack_expect: use conntrack GC to reap expectations netfilter: nf_reject: skip iphdr options when looking for icmp header netfilter: nft_flow_offload: zero device address for non-ether case netfilter: nft_meta_bridge: add validate callback for get operations netfilter: nft_payload: reject offsets exceeding 65535 bytes netfilter: ipset: make sure gc is properly stopped netfilter: ipset: fix order of kfree_rcu() and rcu_assign_pointer() netfilter: ipset: Don't use test_bit() in lockless RCU readers in bitmap types netfilter: ipset: Don't use test_bit() in lockless RCU readers in hash types netfilter: flowtable: fix and simplify IP6IP6 tunnel handling netfilter: xt_cluster: reject template conntracks in hash match netfilter: nf_queue: pin bridge device while NFQUEUE holds fake dst netfilter: flowtable: fix offloaded ct timeout never being extended ==================== Link: https://patch.msgid.link/20260620222738.112506-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>