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2026-08-21Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull RDMA updates from Jason Gunthorpe: "About the normal size, still a lot of AI bug fixes and so on, but some interesting new functionality too: - Assorted locking, bounds-checking, cleanup, and error-path fixes across UCMA/CMA, bng_re, bnxt_re, cxgb4, EFA, ERDMA, HFI1, HNS, ionic, iRDMA, mlx4/mlx5, RXE, SIW, SRP/SRPT, and iSER target. - netlink report for max # of supported resources - get_zeroed_page()/etc removal - Robust udata for ionic - Allow unique RDMA device names per network namespace - Completion counters and v2 admit queue support for EFA - UC QP support for MANA - Completion timestamps for ionic - Harden uverbs data validation and resource lifetime handling, fixing several core use-after-free conditions. - bnxt_re toggle-page ownership and lifetime bug fixes - dmabuf SRQ support for mlx5" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (160 commits) RDMA/ucma: Allow path records to exactly fit the output buffer RDMA/uverbs: Guard legacy bundles without method_elm RDMA/efa: Add support for 128B admin v2 SQ entry RDMA/efa: Generalize the admin SQ RDMA/efa: Decouple admin command payload from admin header RDMA/rxe: Fix OOB in free_rd_atomic_resources() RDMA/cma: Fix WARNING in res_to_rt RDMA/cxgb4: Free debugfs on registration failure RDMA/cxgb4: Cancel reg_work before freeing device on remove RDMA/ucma: Lock the handler in ucma_set_ib_path() RDMA/ucma: Lock the handler in ucma_write_cm_event() RDMA/erdma: restrict the driver to little-endian systems RDMA/ionic: Embed counter driver data in rdma_counter allocation RDMA/ionic: Cap eq_count to the eth driver's interrupt vector budget RDMA/siw: Fix use-after-free in siw_accept() IB/isert: post the full-feature receive buffers after session registration IB/isert: delay the final Login Response until the session is registered RDMA/srp: fix heap information leak on a truncated SRP_CRED_REQ RDMA/erdma: Hold QP references for AE and CM processing RDMA/erdma: Hold CQ references when processing EQ events ...
2026-08-20Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull vhost,vdpa,virtio updates from Michael Tsirkin: - transport v3 support in virtio-mmio - suspend support in vduse - fixes, cleanups all over the place * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (54 commits) vduse: Add suspend vduse: do not take rwsem at reset work flush vduse: add F_QUEUE_READY feature vduse: add VDUSE_SET_FEATURES ioctl vduse: add VDUSE_GET_FEATURES ioctl vduse: store control device pointer tools/virtio: Fix control typo in trace agent comment tools/virtio: Fix userspace typo in vringh test comment vhost: reject zero-size IOTLB INVALIDATE vdpa: Remove redundant dev_err() virtio_ring: fix infinite loop in virtnet_poll_cleantx when device is broken vdpa/mlx5: roll back MR update after VQ setup failure MAINTAINERS: remove Gabriel from LiteX and fw-cfg drivers virtio_mem: fix typo in comment vdpa/solidrun: fix typos in snet_ctrl comments virtio: fix article before virtio in dma-buf comment vhost: fix inaccurate kdoc in iotlb helpers virtio: rtc: time out alarm requests vdpa/mlx5: fix wrong MLX5_ADDR_OF struct type in alloc_inout() vdpa: octeon_ep: add missing MODULE_DEVICE_TABLE() ...
2026-08-20net: bridge: arp/nd proxy: fix reading neigh haNikolay Aleksandrov
Currently neigh ha address is read directly, but that can result in torn/partial reads if the neigh is being updated. Use neigh_ha_snapshot to take a stable snapshot of the address. Fixes: 057658cb33fb ("bridge: suppress arp pkts on BR_NEIGH_SUPPRESS ports") Fixes: ed842faeb2bd ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports") Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260818150756.890025-2-razor@blackwall.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net/smc: free pending qentry in smc_llc_flow_stop() before memsetMahanta Jambigi
smc_llc_flow_stop() resets a flow struct with a blind memset: spin_lock_bh(&lgr->llc_flow_lock); memset(flow, 0, sizeof(*flow)); flow->type = SMC_LLC_FLOW_NONE; spin_unlock_bh(&lgr->llc_flow_lock); If flow->qentry is non-NULL at this point the pointer is overwritten without the allocation being freed, leaking one kmalloc object. A late-arriving duplicate CONFIRM_LINK or ADD_LINK_CONT message can set flow->qentry after the legitimate message has been consumed by the waiter via smc_llc_flow_qentry_clr() (which NULLs the pointer but leaves flow->type non-zero) but before the flow completes and smc_llc_flow_stop() runs. In that window the duplicate is stashed into flow->qentry, and then lost when smc_llc_flow_stop() zeros the struct. Call smc_llc_flow_qentry_del() inside the lock before the memset. smc_llc_flow_qentry_del() already checks flow->qentry before freeing, so the normal case where no entry is pending is a no-op. Fixes: 555da9af827d ("net/smc: add event-based llc_flow framework") Reviewed-by: Hidayath Khan <hidayath@linux.ibm.com> Signed-off-by: Mahanta Jambigi <mjambigi@linux.ibm.com> Link: https://patch.msgid.link/20260818073943.1108383-1-mjambigi@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK ↵Mahanta Jambigi
transition When smc_llc_event_handler() transitions the local LLC flow from SMC_LLC_FLOW_REQ_ADD_LINK to SMC_LLC_FLOW_ADD_LINK on arrival of an ADD_LINK request, it calls smc_llc_flow_qentry_set() unconditionally: if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_REQ_ADD_LINK) { lgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK; smc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry); ... } A CONFIRM_LINK or ADD_LINK_CONT arriving while flow->type is SMC_LLC_FLOW_REQ_ADD_LINK is stashed into flow->qentry via the SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT handler (which stores into flow->qentry for any non-NONE flow type). When the subsequent ADD_LINK arrives, the REQ_ADD_LINK branch overwrites flow->qentry with the new pointer without first freeing the stashed allocation, leaking one kmalloc object. The stashed entry has no consumer: smc_llc_wait() is only called from llc_add_link_work, which is not yet scheduled while the flow type remains REQ_ADD_LINK. No waiter is sleeping on llc_msg_waiter at this point. It is safe to unconditionally free any stashed qentry before the overwrite. Call smc_llc_flow_qentry_del() before smc_llc_flow_qentry_set() in the REQ_ADD_LINK branch. smc_llc_flow_qentry_del() already checks flow->qentry before freeing, so the normal path where no entry is stashed is a no-op. Fixes: b4ba4652b3f8 ("net/smc: extend LLC layer for SMC-Rv2") Reviewed-by: Hidayath Khan <hidayath@linux.ibm.com> Signed-off-by: Mahanta Jambigi <mjambigi@linux.ibm.com> Link: https://patch.msgid.link/20260818073107.466506-1-mjambigi@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20Merge tag 'for-7.3/block-20260819' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull block updates from Jens Axboe: - NVMe updates via Keith: - Enable Clang context analysis for the nvme host driver, adding context annotations across core, fabrics, rdma, tcp and pci - nvmet reservation state exposed through a new namespace-level debugfs directory, plus ABI documentation for the host sysfs and target configfs interfaces - nvme-tcp host memory disclosure fixes on the read path: reject a read that transferred too few bytes, don't accept C2HData based on blk_rq_payload_bytes() alone, and fix the R2T case for a read command - Parallelize nvme-rdma I/O queue allocation and startup (Surabhi) - Apple nvme fixes and quirks: page aligned admin queue buffers, destroy the admin queue on removal, and various DMA/NVMMU correctness fixes - A large pile of nvmet and host fixes for out-of-bounds reads, refcount/resource leaks, and NULL derefs across auth, zns, passthru, pci-epf, rdma and configfs - Various other fixes and cleanups - MD updates via Yu Kuai: - llbitmap reshape support, the large series wiring exact bitmap mapping and reshape lifecycle through raid5 and raid10, growing the page cache in place, and remapping checkpointed bits as reshape progresses - raid5 fixes for lockless max_nr_stripes and recovery_offset accesses, a reshape deadlock with more failed devices than max degraded, and bitmap batch counter consistency - Atomic write handling for raid1/raid10, and removal of the REQ_NOWAIT support from raid1/10/456 - raid5-ppl use-after-free fix in ppl_do_flush() - A batch of smaller fixes across md core and the bitmap code - s390/dasd ESE full-track write support and the surrounding infrastructure, plus enabling CONTEXT_ANALYSIS for s390/block - RWF_DONTCACHE support for block devices, built on new task-context bio completion infrastructure, and wiring it up for the iomap and buffer dropbehind writeback paths - Async io_uring zone reset all, plus zone management command cleanups allowing REQ_NOWAIT and tightening conventional zone rejection - Block integrity refactoring: lift BIP_CHECK_FLAGS to the shared header, handle nogenerate/noverify properly in fs-integrity, and drop the blk-integrity.h include from bdev.c - Split out a new blk_plug.h header - ublk improvements: add UBLK_F_IO_DESC_SIZE, split request validation from io_desc init, reject non-power-of-2 zone sizes in SET_PARAMS, and a series of hardening fixes around map/unmap and auto buf reg - null_blk cleanups and configfs serialization fixes - nbd queue freeze removal on the setup paths, and a new pre_defined_connections module parameter for pre-created devices - blk-cgroup fixes for the race between policy activation and blkg destruction, and accounting per-cpu stats over possible CPUs across blk-stat, iolatency, iocost and kyber - Various dio fixes: leak on metadata mapping error, validate user space vectors during extraction, and set dma_alignment from the backing file for loop and zloop direct I/O - bio cleanups - Various other fixes and cleanups all over * tag 'for-7.3/block-20260819' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (241 commits) nbd: add pre_defined_connections module parameter for pre-created devices nbd: remove queue freeze for newly created nbd from netlink path nbd: factor out a nbd_genl_foreach_sock nbd: skip queue freeze when setting size at device startup nbd: remove queue freeze in nbd_add_socket nbd: clear queue limits on disconnect nbd: disallow NBD_SET_SOCK on an active device nbd: simplify find_fallback() by removing redundant logic blk-mq: add missing call to srcu_barrier() in blk_mq_free_tag_set() block: mtip32xx: synchronize ioctls with device removal ublk: avoid teardown retry loop on xarray allocation failure null_blk: fix UBSAN shift-out-of-bounds when zone_size is 0 or overflows block: don't include blk-integrity.h in bdev.c xfs: avoid double deferrals for RWF_DONTCACHE writes loop: Fix recently introduced lock inversion block: set QUEUE_FLAG_DYING unconditionally in blk_mark_disk_dead() swim3: Add missing MODULE_DESCRIPTION selftests: ublk: add SET_PARAMS validation test selftests: ublk: add helper for SET_PARAMS ublk: reject non-power-of-2 zone sizes in SET_PARAMS ...
2026-08-20sctp: drop a chunk if its transport was removedHyunwoo Kim
sctp_rcv() resolves the transport once per packet and leaves it in chunk->transport. The lookup reference, or the one sctp_add_backlog() takes if the socket is owned by userspace, keeps it around until the chunk has been processed. An authenticated ASCONF DEL-IP can remove it in the meantime. sctp_assoc_rm_peer() takes the transport out of the association and calls sctp_transport_free(), which tags it dead and drops the reference the association held. There is a window on both paths: the packet can sit on the socket backlog, and on the direct path the lookup completes before bh_lock_sock(). The DATA chunk in that packet puts the removed transport back into asoc->peer.last_data_from. Once the packet is done that reference goes away and the transport is freed by RCU, so the next delayed SACK carries the pointer into the SACK chunk and sctp_outq_select_transport() reads the freed transport's state. Drop the chunk in sctp_inq_push(), next to the existing rcvr->dead check. Both paths reach it with the association's socket lock held. The peer retransmits it. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/aoUJHQmxL0LFIMCw@v4bel Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net: sched: fix 32-bit backlog wrap in gred, bfifo and plug enqueueJamal Hadi Salim
gred_enqueue(), bfifo_enqueue() and plug_enqueue() admit a packet when the current backlog plus the packet length fits within the queue limit: sch->qstats.backlog + qdisc_pkt_len(skb) <= sch->limit (gred default VQ) gred_backlog+qdisc_pkt_len(skb) <= q->limit (gred configured VQ) sch->qstats.backlog + qdisc_pkt_len(skb) <= sch->limit (bfifo) sch->qstats.backlog + skb->len <= q->limit (plug) sch->qstats.backlog and q->backlog are u32, and qdisc_pkt_len()/skb->len are unsigned int, so all sums are computed in 32 bits and wrap at 2^32. Once the true backlog exceeds 4 GiB the wrapped sum becomes small and admission keeps succeeding, so the queue grows without bound and the kernel can be driven to OOM. Promote the sums to u64 so admission stops once the true backlog exceeds the limit. The limit is u32, so the bounded queue stays below 2^32 and the stored u32 backlog never wraps. The bug can only be reproduced as root (albeit with ridiculous setup): attach a gred (or bfifo/plug) qdisc with a limit near 4 GiB, leaving the default VQ unconfigured (for gred), and drive >4 GiB of queued traffic (e.g. via a size table / stab to inflate qdisc_pkt_len, or sustained high-rate traffic). The u32 backlog+len sum wraps at 2^32, admission keeps succeeding, and the queue grows unboundedly to OOM. Fixes: a3eb95f891d6 ("net_sched: gred: add TCA_GRED_LIMIT attribute") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260818095927.15901-1-jhs@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net: tcp: block mixing readable and unreadable fragsMina Almasry
Protect tcp_sendmsg_locked() from mistakenly mixing readable and unreadable page fragments in the same SKB. Check that the devmem binding matches the existing SKB's readability. If a mismatch is detected, avoid collapsing and create a new segment. Fixes: bd61848900bff ("net: devmem: Implement TX path") Suggested-by: Eric Dumazet <edumazet@google.com> Cc: Pavel Begunkov <asml.silence@gmail.com> Cc: Stanislav Fomichev <sdf@fomichev.me> Cc: Bobby Eshleman <bobbyeshleman@gmail.com> Signed-off-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/20260814191336.187243-2-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net: core: propagate unreadable flag in skb_zerocopyMina Almasry
skb_zerocopy() fails to propagate the unreadable flag when copying unreadable fragments, causing target skbs to appear as readable memory. This patch fixes the flag propagation. Additionally, it returns -EFAULT if readable fragments are mixed with unreadable fragments during extraction, and returns -EFAULT in openvswitch queue_userspace_packet(). Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags") Cc: Stanislav Fomichev <sdf@fomichev.me> Cc: Bobby Eshleman <bobbyeshleman@gmail.com> Cc: Florian Westphal <fw@strlen.de> Cc: Aaron Conole <aconole@redhat.com> Cc: Eelco Chaudron <echaudro@redhat.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Ilya Maximets <i.maximets@ovn.org> Link: https://patch.msgid.link/20260814191336.187243-1-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net/packet: defer vmalloc TX_RING free until skbs finishKyle Zeng
AF_PACKET TX_RING skbs keep a raw pointer to their ring frame. The skb page references preserve page-backed ring blocks after pg_vec is freed, but they do not preserve a vmalloc mapping. tpacket_destruct_skb() currently drops the pending reference before writing the timestamp and TP_STATUS_AVAILABLE to the frame. Move the decrement after those stores. The smp_wmb() in __packet_set_status() orders the frame stores before the decrement. Also recheck pending TX frames under pg_vec_lock before non-closing ring replacement, so a racing send cannot add a pending skb between the initial check and the ring swap. Ring allocation can produce a mixture of page-backed and vmalloc-backed blocks. Allocate deferred-work storage during TX ring setup when the first vmalloc-backed block is encountered, and keep its pointer in the pg_vec allocation header. If allocation fails, return -ENOMEM from ring setup. On socket close, a non-NULL pointer identifies a vmalloc-backed vector without a scan. If TX skbs remain, defer the whole vector to system_long_wq. After pg_vec is detached, a late destructor can skip the pending decrement. Use socket write-memory accounting as the deferred lifetime gate instead: an skb remains charged through its final sock_wfree(), after all ring-frame accesses. The delayed work retains a socket reference and reschedules itself until no TX skbs remain. Move pending_refcnt release to packet_sock_destruct() so late skb destructors and deferred cleanup can safely use it after packet_release(). Page-backed teardown remains synchronous, and no lock is added to the TX completion hot path. Fixes: b013840810c2 ("packet: use percpu mmap tx frame pending refcount") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/netdev/20260721015824.45829-1-kylebot@openai.com/ Suggested-by: Eric Dumazet <edumazet@google.com> Suggested-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Kyle Zeng <kylebot@openai.com> Link: https://patch.msgid.link/20260816235646.76500-1-kylebot@openai.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20vlan: fix skb_under_panic and races when toggling HW VLAN offloadEric Dumazet
Toggling hardware VLAN TX offload (NETIF_F_HW_VLAN_CTAG_TX or NETIF_F_HW_VLAN_STAG_TX) on a lower device invokes vlan_transfer_features(), which dynamically changed vlandev->hard_header_len. This causes two issues: 1. Lockless TX paths (e.g. packet_snd in af_packet.c, ip6_finish_output2) read dev->hard_header_len without holding RTNL lock. Mutating hard_header_len dynamically under RTNL creates a data race where upper layers reserve insufficient headroom based on a stale hard_header_len, resulting in skb_under_panic when vlan_dev_hard_header() is called. 2. In addition, vlan_transfer_features() updated hard_header_len without updating header_ops, causing a mismatch between allocated headroom and header creation. Always setting dev->hard_header_len = real_dev->hard_header_len and dev->needed_headroom = real_dev->needed_headroom + VLAN_HLEN unconditionally ensures: - dev->hard_header_len remains 100% static and immutable at real_dev->hard_header_len, eliminating all dynamic runtime updates and data races on hard_header_len. - Upper layers allocating skbs via LL_RESERVED_SPACE() will always reserve sufficient headroom for software VLAN tag insertion (real_dev->hard_header_len + real_dev->needed_headroom + VLAN_HLEN). - vlandev inherits real_dev->needed_tailroom so underlying trailer/padding/ICV requirements are honored. - AF_PACKET SOCK_RAW network header offsets remain correctly aligned at real_dev->hard_header_len. - vlan_header_ops is used unconditionally. Note to stable teams: Make sure to backport these commits: e16e960d55a4 ("ipvlan: inherit needed_headroom and needed_tailroom from phy_dev") cef51860becd ("macvlan: inherit needed_headroom and needed_tailroom from lowerdev") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Tangxin Xie <xietangxin@h-partners.com> Closes: https://lore.kernel.org/netdev/99d678ae-c7b2-4b44-b534-b8320679deb3@h-partners.com/ Cc: <stable@vger.kernel.org> # 3.19: e16e960d55a4: ipvlan: inherit needed_headroom and needed_tailroom from phy_dev Cc: <stable@vger.kernel.org> # 3.19: cef51860becd: macvlan: inherit needed_headroom and needed_tailroom from lowerdev Cc: <stable@vger.kernel.org> # 3.19 Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260811085246.2267779-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20batman-adv: reject unrepresentable multicast TVLV offsetsKyle Zeng
The network and transport header fields in struct sk_buff are 16-bit offsets from skb->head, and U16_MAX is reserved as the unset transport header value. batadv_tvlv_call_handler() sets both fields from a received multicast TVLV without checking whether the TVLV end is representable. If the end offset exceeds the field's range, skb_set_transport_header() truncates it so that the transport header precedes the network header. The negative difference is then returned by skb_network_header_len() as a large u32. batadv_mcast_forw_packet() consequently accepts an oversized multicast tracker and accesses memory beyond the skb data. Add skb_set_transport_header_careful(), an offset-aware counterpart to skb_reset_transport_header_careful(), which validates the final head-relative offset before assigning it. Use the new helper in batadv_tvlv_call_handler() and reject unrepresentable TVLVs before setting the network header. Fixes: 07afe1ba288c ("batman-adv: mcast: implement multicast packet reception and forwarding") Cc: stable@vger.kernel.org Signed-off-by: Kyle Zeng <kylebot@openai.com> Co-developed-by: David Lee <david.lee@trailofbits.com> Signed-off-by: David Lee <david.lee@trailofbits.com> Acked-by: Sven Eckelmann <sven@narfation.org> Link: https://patch.msgid.link/20260817084955.944189-1-david.lee@trailofbits.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20ipv6: seg6: clear IPv4 control block on IPIP decapsulationKyle Zeng
End.DX4 and End.DT4 decapsulate an IPv4 packet through decap_and_validate() and send it directly to IPv4 routing. The inner packet therefore bypasses ip_rcv_core(), which normally clears IPCB before IPv4 interprets skb->cb. The skb instead retains IP6CB data from the outer packet. IP6CB and IPCB use the same skb->cb storage, so IP6CB(skb)->lastopt overlaps IPCB(skb)->opt.optlen and srr, while IP6CB(skb)->nhoff overlaps rr and ts. The sender can make the stale optlen byte nonzero with a valid outer extension-header chain. The reproducers put an eight-byte Destination Options header immediately after the 40-byte IPv6 header and before the Segment Routing Header. ipv6_destopt_rcv() records the sender-controlled Destination Options offset in both lastopt and nhoff, setting them to 40. On the reproduced little-endian x86-64 kernel, IPv4 therefore sees optlen = 40 and rr = 40. Both tcp_v4_save_options() and __ip_options_echo() skip option copying when optlen is zero. Here optlen is 40, so the TCP SYN path allocates room for 40 bytes of option data and calls __ip_options_echo(). The stale rr value makes that function read inner packet byte 41 as the Record Route option length. The reproducers set that sender-controlled byte to 255, so __ip_options_echo() copies 255 bytes into the 40-byte option-data area. Separate End.DX4 and End.DT4 reproducers on the unpatched v7.2-rc5 kernel both produced: BUG: KASAN: slab-out-of-bounds in __ip_options_echo() Write of size 255 The relevant End.DX4 call path is: __ip_options_echo tcp_v4_route_req tcp_conn_request tcp_v4_conn_request tcp_rcv_state_process tcp_v4_do_rcv tcp_v4_rcv ip_protocol_deliver_rcu ip_local_deliver_finish ip_local_deliver input_action_end_dx4_finish input_action_end_dx4 The relevant End.DT4 call path is: __ip_options_echo tcp_v4_route_req tcp_conn_request tcp_v4_conn_request tcp_rcv_state_process tcp_v4_do_rcv tcp_v4_rcv ip_protocol_deliver_rcu ip_local_deliver_finish ip_local_deliver input_action_end_dt4 tcp_v4_save_options() is inlined into the tcp_v4_route_req() path, so it does not appear as a separate frame. When decap_and_validate() handles IPPROTO_IPIP, save the ingress interface from IP6CB, clear IPCB, and restore the saved value. Doing this in the common decapsulation path covers End.DX4, End.DT4, and End.DT46's IPv4 arm. Use IP6CB(skb)->iif rather than skb->skb_iif. These actions run after l3mdev processing, which can replace skb_iif with the L3 master; IP6CB iif still records the receiving interface set at IPv6 ingress. Fixes: 891ef8dd2a8d ("ipv6: sr: implement additional seg6local actions") Cc: stable@vger.kernel.org Suggested-by: Andrea Mayer <andrea.mayer@uniroma2.it> Signed-off-by: Kyle Zeng <kylebot@openai.com> Co-developed-by: David Lee <david.lee@trailofbits.com> Signed-off-by: David Lee <david.lee@trailofbits.com> Reviewed-by: Andrea Mayer <andrea.mayer@uniroma2.it> Link: https://patch.msgid.link/20260817085839.946321-1-david.lee@trailofbits.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20inetpeer: randomize RB-tree node comparison using SipHashEric Dumazet
The inetpeer rate limiting system stores peer entries in a Red-Black tree keyed deterministically on the remote IP address. Because tree lookups walk the RB-tree using standard lexicographical comparisons (inetpeer_addr_cmp), an off-path adversary can predict the exact topology of the tree and the sequence of nodes traversed during lookups (the gc_stack candidate list). By combining deterministic tree traversal with aggressive garbage collection (triggered when tree size exceeds inet_peer_threshold), an attacker can selectively force the eviction of targeted inet_peer nodes. When an evicted node is subsequently re-created upon receiving a new packet, its rate-limiting token bucket (rate_tokens, rate_last) is reset to full capacity. This creates a side-channel primitive allowing off-path attackers to bypass IP-keyed ICMP rate limits and infer open UDP ports (similar to SAD DNS style attacks). Mitigate this by randomizing the RB-tree node comparison logic using SipHash with a secret key (inetpeer_hash_key) initialized via net_get_random_once(). Nodes are ordered in the tree by SipHash(addr, key) rather than raw IP addresses. Because the secret key is unknown to external entities, the tree layout and lookup traversal paths are unpredictable to off-path adversaries, breaking the deterministic eviction gadget. Cache the computed 64-bit SipHash (hash) in struct inet_peer and compute the target hash (dhash) once at the beginning of inet_getpeer() to avoid recomputing SipHash at every step of the RB-tree walk. Fixes: b145425f269a ("inetpeer: remove AVL implementation in favor of RB tree") Reported-by: Michael Blunt <michaelbblunt@gmail.com> Suggested-by: Michael Blunt <michaelbblunt@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260818151213.3953963-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20ip6mr: do not clone dst in ip6mr_cache_report()Eric Dumazet
IPv6 input attaches a non-refcounted (NOREF) dst to skbs under RCU. When an ingress multicast packet misses MFC lookup, ip6mr_cache_unresolved() places the skb onto the unresolved queue, escaping the receive-side RCU grace period. If the underlying route is deleted and freed, and the MFC queue is later resolved with a wrong parent interface, ip6_mr_forward() invokes ip6mr_cache_report(..., MRT6MSG_WRONGMIF), which executes dst_clone(skb_dst(pkt)) on the freed dst entry, triggering a slab use-after-free. Report packets queued to mroute6_sk (a raw socket) and netlink notifications do not require an attached dst entry. Fix this by: 1. Removing dst_clone() in ip6mr_cache_report() and ensuring report skbs do not hold a dst. 2. Dropping skb_dst before queuing unresolved skbs in ip6mr_cache_unresolved(), matching the fact that multicast forwarding resolves outgoing routes anew via ip6_route_output(). Fixes: 67f415dd2906 ("ipv6: convert rx data path to not take refcnt on dst") Reported-by: Zero Day Initiative <zdi-disclosures@trendmicro.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Hangbin Liu <liuhangbin@kylinos.cn> Link: https://patch.msgid.link/20260818172755.4083692-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20mptcp: fix uninitialized local_id in syncookie MP_JOIN reconstructionHarshit Varu
mptcp_token_join_cookie_init_state() restores remote_nonce, local_nonce, backup, join_id, token and msk from the saved cookie entry when rebuilding the request socket for a MP_JOIN 4th-ACK handled under SYN cookies, but it does not restore local_id, even though the SYN path saved it. subflow_ulp_clone() then reads that uninitialized field and stores it as the joined subflow's address-ID. Because the request-sock slab is SLAB_TYPESAFE_BY_RCU and not zeroed on allocation, the value is the stale byte of a previously freed request socket, which an off-path peer can influence by sending concurrent MP_JOIN SYNs. This corrupts the path manager's id-based subflow bookkeeping for the connection. Restore subflow_req->local_id from the cookie entry, as done for the other fields. Fixes: 9466a1ccebbe ("mptcp: enable JOIN requests even if cookies are in use") Cc: stable@vger.kernel.org Signed-off-by: Harshit Varu <harshitvaru666@gmail.com> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20260815115205.197151-1-harshitvaru666@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net: add missing ref_tracker_dir_exit() to net_passive_dec()Tetsuo Handa
I found that trying to read /sys/kernel/debug/ref_tracker/* causes NULL pointer dereference crash when alloc_netdev_mqs() via unshare() returned NULL, for commit 9ba74e6c9e9d ("net: add networking namespace refcount tracker") added ref_tracker_dir_exit(&net->refcnt_tracker) to only __put_net() path whereas commit 65b584f53611 ("ref_tracker: automatically register a file in debugfs for a ref_tracker_dir") added ref_tracker_dir_debugfs() to ref_tracker_dir_init() path. Since preinit_net() calls ref_tracker_dir_init(&net->refcnt_tracker) and ref_tracker_dir_init(&net->notrefcnt_tracker), we need to make sure that both ref_tracker_dir_exit(&net->refcnt_tracker) and ref_tracker_dir_exit(&net->notrefcnt_tracker) are called before net_passive_dec() schedules for kmem_cache_free() via net_complete_free(). ref_tracker_dir_exit(&net->refcnt_tracker) is called via put_net() when ns_ref_put() returned true. But put_net() is not called when copy_net_ns() fails. Therefore, call ref_tracker_dir_exit() from net_passive_dec() if put_net() is not yet called. Link: https://sashiko.dev/#/patchset/b06ce35d-e7bc-47a5-8e0a-e82be7e4dd08%40I-love.SAKURA.ne.jp Fixes: 9ba74e6c9e9d ("net: add networking namespace refcount tracker") Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://patch.msgid.link/64254d80-9248-466c-8108-95f43bd71117@I-love.SAKURA.ne.jp Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20Merge tag 'nfsd-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linuxLinus Torvalds
Pull nfsd updates from Chuck Lever: - CB_NOTIFY support for NFSD's NFSv4.1 directory delegations The server used to recall a delegation as soon as the directory changed. NFSD now watches delegated directories through fsnotify and reports adds, removes, renames, and directory attribute changes, carrying the filehandle and attributes of the affected entry, so clients can keep their caches. Some of the NOTIFY4 flags come from RFC 8881bis (Jeff Layton) - Continued netlink work A new server-stats-get operation reports what /proc/net/rpc/nfsd publishes, plus NFSv4 callback counts, and SUNRPC now keeps its per-procedure call counts per network namespace, so a container sees its own numbers. nfsstat reads all of this over netlink, with a procfs fallback for older kernels (Jeff Layton) - Remove SUNRPC service thread pool mode selection Per node is the right choice on any host we run today, so the auto, global, and percpu modes have been removed. A single-node host still gets one pool. A multi-NUMA host now gets a pool per node. sunrpc.pool_mode accepts the old names but no longer selects anything. - Bug fixes, clean-ups, and small optimizations: - async COPY offload rework (Jeff Layton) - more use-after-free fixes in the NFSv4 state revocation paths - percpu counter contention removed from the reply cache and IO accounting - a long list of hardening fixes (Chris Mason) Sincere thanks to all contributors, reviewers, testers, and bug reporters who participated in the v7.3 NFSD development cycle. * tag 'nfsd-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (182 commits) nfsd: export NFSv4 callback op stats via netlink nfsd: count NFSv4 callback operations per netns sunrpc: remove unused svc_version vs_count field nfsd: implement server-stats-get netlink handler sunrpc: use per-net counts in svc_seq_show() sunrpc: add per-netns per-procedure call counts to svc_stat NFSD: Document reply_cache_stats ABI NFSD: Eliminate percpu counter contention in IO byte accounting NFSD: Eliminate percpu counter contention in reply cache statistics NFSD: Eliminate percpu counter contention in DRC memory accounting NFSD: Fix off-by-one in DRC bucket pruning limit NFSD: Relocate NFSv4 "supported attributes" to new header NFSD: Relocate nfsd4_set_netaddr() NFSD: Relocate nfsd_user_namespace() NFSD: Move struct readdir_cd NFSD: Move the export.h include from nfsd.h to auth.c NFSD: Remove '#include "nfsd.h"' from fs/nfsd/cache.h NFSD: include "netns.h" NFSD: Explicitly include "stats.h" NFSD: Make "stats.h" self-contained ...
2026-08-20ipv6: avoid divide by zero in rt6_multipath_rebalanceCen Zhang (Microsoft)
rt6_multipath_rebalance() calculates the total eligible nexthop weight in one pass and programs upper bounds in a second pass. Since RTM_NEWROUTE is RTNL-free, a concurrent ignore_routes_with_linkdown update can make the first pass return zero while the second sees an eligible nexthop, causing rt6_upper_bound_set() to divide by zero. UBSAN: division-overflow in net/ipv6/route.c:4845:17 Oops: divide error: 0000 [#1] SMP KASAN NOPTI rt6_upper_bound_set() net/ipv6/route.c:4845 rt6_multipath_rebalance() fib6_add_rt2node() ip6_route_multipath_add() inet6_rtm_newroute() Skip upper-bound calculation when the first pass reports a zero total. This respects the lock-free performance considerations here and solves insecure scenarios. Fixes: bd11ff421d36 ("ipv6: Get rid of RTNL for SIOCDELRT and RTM_DELROUTE.") Reported-by: AutonomousCodeSecurity@microsoft.com Reported-by: Xiang Mei (Microsoft) <xmei5@asu.edu> Reported-by: Cen Zhang (Microsoft) <blbllhy@gmail.com> Signed-off-by: Cen Zhang (Microsoft) <blbllhy@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260817013237.2797-1-blbllhy@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net: mctp: hold a reference to the route device in mctp_route_lookup()Aldo Ariel Panzardo
mctp_route_lookup() uses rt->dev without holding a reference on it. mctp_route_lookup_single() returns the route under RCU only, so the route's device can be torn down concurrently: mctp_dev_put() drops the last reference and synchronously kfree()s mdev->addrs. mctp_dev_saddr() then reads rt->dev->addrs[0], giving a use-after-free reachable by an unprivileged local AF_MCTP user on the receive/forwarding path (no CAP_NET_RAW required): BUG: KASAN: slab-use-after-free in mctp_route_lookup Read of size 1 at addr ... by task mctp_uaf/... mctp_route_lookup mctp_pkttype_receive Freed by task ...: kfree mctp_dev_put mctp_dev_notify In the same window mctp_dst_from_route() -> mctp_dev_hold() also increments a refcount that has already reached zero ("refcount_t: addition on 0 ... mctp_dev_hold"). This reintroduces the use-after-free class of CVE-2023-3439: the source address lookup was moved ahead of the point where the destination takes its device reference. Take a reference with refcount_inc_not_zero() before touching rt->dev, skip a device that is already dead, and drop the reference once the destination has taken its own. Fixes: 22cb45afd221 ("net: mctp: perform source address lookups when we populate our dst") Cc: stable@vger.kernel.org Signed-off-by: Aldo Ariel Panzardo <qwe.aldo@gmail.com> Link: https://patch.msgid.link/20260813022102.2792032-1-qwe.aldo@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20ipv6: rpl: fix NULL dereference of idev in ipv6_rpl_srh_rcv()Andrea Mayer
ipv6_rpl_srh_rcv() dereferences idev from __in6_dev_get() without a NULL check when reading idev->cnf.rpl_seg_enabled. When the device's MTU drops below IPV6_MIN_MTU, addrconf_ifdown() clears dev->ip6_ptr through RCU_INIT_POINTER(). A packet that passed the idev check in ip6_rcv_core() can then reach ipv6_rpl_srh_rcv() with dev->ip6_ptr already NULL. Reproduced by flooding the receiving interface with ping6 traffic while flapping its MTU between 1500 and 1200: BUG: KASAN: null-ptr-deref in ipv6_rpl_srh_rcv+0xb3/0x1070 Read of size 4 at addr 00000000000006b4 by task ping6/394 CPU: 2 UID: 0 PID: 394 Comm: ping6 Not tainted 7.2.0-rc7-micro-vm-dev-00095-g24ef02f934ee #240 PREEMPT(full) Call Trace: <IRQ> kasan_report+0xc6/0x100 ipv6_rpl_srh_rcv+0xb3/0x1070 ip6_protocol_deliver_rcu+0x759/0x9a0 ip6_input_finish+0xa8/0x1b0 ip6_input+0xe1/0x490 ipv6_rcv+0x33d/0x460 __netif_receive_skb_one_core+0xd6/0x130 process_backlog+0x2cc/0xa00 __napi_poll.constprop.0+0x56/0x270 net_rx_action+0x327/0x730 handle_softirqs+0x11e/0x630 do_softirq+0xb3/0xf0 </IRQ> Both ipv6_rpl_srh_rcv() and ipv6_srh_rcv() are called only from ipv6_rthdr_rcv(), which already has an idev lookup. Fix the NULL dereference on the RPL path by checking idev in ipv6_rthdr_rcv(), before it calls either function. The callees take idev as an argument and no longer call __in6_dev_get(), so the packet is now dropped in one place, with SKB_DROP_REASON_IPV6DISABLED on both paths. Fixes: 8610c7c6e3bd ("net: ipv6: add support for rpl sr exthdr") Cc: stable@vger.kernel.org Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it> Tested-by: Xiang Mei <xmei5@asu.edu> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260817132644.2223-1-andrea.mayer@uniroma2.it Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net/tcp-ao: fix use-after-free of current_key on reconnect to another peerHyunwoo Kim
tcp_inbound_ao_hash() is called before bh_lock_sock_nested() is taken, with only rcu_read_lock() held. On the fast path for established sockets, if the rnext_keyid sent by the peer differs from current_key->sndid, the key the peer asked for is looked up and stored in current_key. The lookup is inside the RCU read side, but current_key outlives it. When the socket is disconnected and connect() is called again for another peer, tcp_ao_connect_init() unlinks every key that does not match the new peer and frees it with call_rcu(). If current_key points at such a key, it is cleared to NULL. The fast path reads sk_state only once on entry, so a softirq that got into it while the socket was still established can update current_key after that loop has already run. The update is inside the RCU read side, so it comes before the call_rcu() callback, and once the callback frees the key, current_key is left pointing at freed memory. The next transmission picks that pointer up in tcp_get_current_key(). tcp_ao_transmit_skb() then reads the traffic key from the freed object, which is the use-after-free. Wait for one grace period before unlinking, and only if a key is going to be removed. By the time tcp_connect() runs the socket is already in TCP_SYN_SENT, and TCP_AO_ESTABLISHED does not contain TCPF_SYN_SENT, so a softirq entering after the wait cannot reach the fast path, and the ones already in it have finished. The existing NULL handling in the loop is then enough. Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments") Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://patch.msgid.link/aoIriv3pHDgII2YR@v4bel Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net/sched: add get_fill_size callbacks for actions missing themVictor Nogueira
Several tc actions - act_police, act_bpf, act_pedit, act_ife, act_sample, act_ct, act_ctinfo and act_tunnel_key among them - provide no get_fill_size() callback, so tcf_action_fill_size() falls back to tcf_action_shared_attrs_size() which does not account for the action-specific netlink attributes emitted inside TCA_ACT_OPTIONS by their dump functions. When an RTM_NEWACTION request with NLM_F_ECHO (or an RTNLGRP_TC listener) creates several actions, tcf_add_notify_msg() allocates the echo skb from this underestimated size. When this happens, the act_api code fails to add all of the fields to the netlink message and, thus, fails to send it. Issue is that, when that happens, this failure doesn't stop the action instances from being added. So any user watching these events will be under the false impression that no actions were created at all. For example, act_pedit overruns with 32 actions of four munge keys each, act_police with 32 policers once the optional rate/peakrate/result/avrate attributes are present. To fix this, add the missing get_fill_size callbacks returning the worst-case size of each action's dump attributes, following the pattern used by act_gact/act_skbedit/act_vlan. Also widen the TCA_GACT_TM accounting in tcf_action_shared_attrs_size() to nla_total_size_64bit(), since actions dump their tcf_t with nla_put_64bit(), which may be preceded by an NLA_PAD attribute. Note: We only provided fixes for the actions we reproduced this bug with as of today. We can send a separate hardening patch for the remaining actions to net-next later. The other pre-existing issues, pointed out by Clashiko [1], will be fixed in upcoming patches. [1] https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260810164357.1653956-1-victor%40mojatatu.com Fixes: 4e76e75d6aba ("net sched actions: calculate add/delete event message size") Reported-by: Vega <vega@nebusec.ai> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260816201327.2435335-1-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net: advertise TCP MSS from the configured MTU, not the learned PMTUJiayuan Chen
The MSS a host puts in its SYN tells the peer how big a segment it may send us. Right now we can shrink it with a PMTU we learned on our own send path, which is the wrong direction entirely. On asymmetric paths this bites - think DSR load balancers, where the request side goes through a smaller-MTU overlay. We learn a small PMTU going out, then advertise a small MSS, and the peer stays capped for the whole connection even though its path back to us is wide. MSS only shows up in the SYN and never grows back. On symmetric paths we lose nothing by dropping it either: the peer runs its own PMTU discovery and usually already knows the real path MTU. So work out the advertised MSS from the configured route or device MTU and ignore the learned PMTU. Our send side is unchanged, still clamped by tcp_current_mss(). Add ip_dst_mtu_configured()/ip6_dst_mtu_configured() and use them from the two default_advmss() paths. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Fixes: 164a5e7ad531 ("ipv4: ipv4_default_advmss() should use route mtu") Cc: stable@vger.kernel.org Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260815070413.294559-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20Merge tag 'ipsec-2026-08-18' of ↵Jakub Kicinski
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2026-08-18 1) xfrm6: fix out-of-bounds write in xfrm6_input_addr() when secpath is full Tighten the secpath-depth check so a full chain can't write past xvec[]. 2) Add and revert "esp: do not unref managed frag pages in esp_ssg_unref()" The patch does not fully fully resolve the issue, a corrected version will follow. 3) xfrm: espintcp: fix UAF during close Synchronize espintcp close with the xfrm_trans_reinject work queue so the freed socket message isn't dereferenced again. 4) xfrm: drop ESP-in-TCP packets with no ingress device Drop queued ESP-in-TCP records whose saved ingress device has gone away, avoiding a NULL device deref in the XFRM input path. 5) xfrm: avoid lock inversion in nat keepalive work Split the NAT keepalive walk into a reference-collection phase and a per-state lock phase to break the AB-BA with state removal. This patch has some issues that are fixed with a followup patch. 6) xfrm: Fix skb double-free in xfrm_dev_direct_output() Stop freeing the skb unconditionally in xfrm_dev_direct_output(), letting local_out()'s result indicate when ownership has moved on. 7) xfrm: ah6: validate routing header segments_left Validate the segments_left/hdrlen invariant before rearranging the routing-header addresses, avoiding an OOB memmove on malformed HDRINCL packets. 8) xfrm: fix xfrm_state_construct() auth-trunc leak Detect an already-attached auth-trunc allocation by the pointer rather than inferring it from the algorithm id, so a prior attach isn't overwritten and lost. 9) xfrm: bound nat keepalive state collection Replace the per-state allocation in the NAT keepalive walk with a fixed-size batch that drains under BH-disabled locking and resumes from the cursor, bounding the worker's memory. * tag 'ipsec-2026-08-18' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec: xfrm: bound nat keepalive state collection Revert "esp: do not unref managed frag pages in esp_ssg_unref()" xfrm: fix xfrm_state_construct() auth-trunc leak xfrm: ah6: validate routing header segments_left xfrm: Fix skb double-free in xfrm_dev_direct_output() xfrm: avoid lock inversion in nat keepalive work xfrm: drop ESP-in-TCP packets with no ingress device xfrm: espintcp: fix UAF during close esp: do not unref managed frag pages in esp_ssg_unref() xfrm6: fix out-of-bounds write in xfrm6_input_addr() when secpath is full ==================== Link: https://patch.msgid.link/20260818092920.653034-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20Merge tag 'nf-next-26-08-18' of ↵Jakub Kicinski
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next Pablo Neira Ayuso says: ==================== Netfilter/IPVS fixes for net-next This contains fixes for nf_tables, revisit issues with expectation infra updates reported by sashiko, an ipset fix for deletions in the hash:net type and tne fix for the IPVS FTP helper. 1) Validate layer 4 header mangling done via nfnetlink_queue and nft_payload, this is a follow up to recent similar validation at layer 3. From Zhiling Zou. 2) Do not allocate memory on delete operations in ipset hash:net type, delete operation must always succeed. From Florian Westphal. 3) Deliver nft_obj overquota packet path notification directly via nfnetlink, do not use the control plane batch logic. From Fourie Zhang. 4) Follow up to controlidate check for reinserted dead expectations, to cover the nf_conntrack_expect_related_pair() function too. 5) Do not expose expectation dead flag to userspace via ctnetlink. 6) Make commit set_update_list per-netns to prepare to publish set clone earlier. 7) Publish the set clone earlier from commit path to address set lookup failures during table re-creation, this is targetting the rbtree and pipapo set backends. 8) Fix an integer overflow in the IPVS FTP helper. A similar fix was already proposed for the conntrack FTP helper months ago. From Joas Antonio dos Santos. * tag 'nf-next-26-08-18' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next: ipvs: fix integer overflow in ftp helper port/address parsing netfilter: nf_tables: call set ops .commit when building new ruleset blob netfilter: nf_tables: move set_update_list to nftables per-netns netfilter: ctnetlink: do not expose expectation DEAD flag netfilter: nf_conntrack_expect: consolidate check for insertion of dead expectation netfilter: nf_tables: don't queue packet path object notifications netfilter: ipset: remove need to allocate memory on delete operations netfilter: validate L4 headers after userspace packet writes ==================== Link: https://patch.msgid.link/20260817232957.1281637-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20ipv6: use RCU iterator to dump route exceptionsYuyang Huang
rt6_nh_dump_exceptions() uses hlist_for_each_entry() to iterate over RCU-protected exception lists. The caller holds rcu_read_lock(), but does not hold rt6_exception_lock, so rt6_insert_exception() can concurrently add an entry with hlist_add_head_rcu(). KCSAN reports this race (irrelevant details omitted): ================================================================== BUG: KCSAN: data-race in rt6_insert_exception / rt6_nh_dump_exceptions write (marked) to 0xffff8a7c44c59620 of 8 bytes by interrupt on cpu 5: rt6_insert_exception+0x3bb/0x760 __ip6_rt_update_pmtu+0x4fe/0x750 ip6_sk_update_pmtu+0x19a/0x3b0 udpv6_err+0x3ff/0x800 icmpv6_notify+0x1e1/0x440 icmpv6_rcv+0x8c0/0xab0 ip6_protocol_deliver_rcu+0x616/0x840 ip6_input_finish+0xb9/0x160 ... entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff8a7c44c59620 of 8 bytes by task 549 on cpu 14: rt6_nh_dump_exceptions+0xb3/0x260 rt6_dump_route+0x53e/0x5f0 fib6_dump_node+0x6d/0xf0 fib6_walk_continue+0x290/0x2d0 fib6_dump_table+0x28d/0x360 inet6_dump_fib+0x37d/0x620 rtnl_dumpit+0x7b/0xd0 netlink_dump+0x3ae/0x7e0 ... entry_SYSCALL_64_after_hwframe+0x77/0x7f 4 locks held by dumper/549: ... #1: (rcu_read_lock){....}-{1:3}, at: inet6_dump_fib+0x88/0x620 #2: (&tb->tb6_lock){+.-.}-{3:3}, at: fib6_dump_table+0x1e9/0x360 #3: (rcu_read_lock){....}-{1:3}, at: rt6_dump_route+0x483/0x5f0 value changed: 0xffff8a7c44e05700 -> 0xffff8a7c45d60100 Reported by Kernel Concurrency Sanitizer on: CPU: 14 UID: 0 PID: 549 Comm: dumper Not tainted 7.2.0-rc7-virtme #38 PREEMPT(lazy) ... Use hlist_for_each_entry_rcu() to safely iterate over the exception list. Fixes: 1e47b4837f3b ("ipv6: Dump route exceptions if requested") Cc: stable@vger.kernel.org Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260815084651.69477-1-sigefriedhyy@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20net: bridge: Reject descending VLAN tunnel rangesRuoyu Wang
A pair of descending VLAN and tunnel IDs can pass the tunnel range span check. The VLAN subtraction produces a negative int, which is converted to unsigned when compared with the u32 tunnel ID subtraction. It can therefore equal the wrapped tunnel ID delta. The range loop then performs no iterations. Since the batched notification handling added a post-loop error check, this leaves err uninitialized and makes the request's return value unpredictable. Reject descending VLAN ranges before comparing the spans. Valid ascending and single-entry ranges remain unchanged, while malformed descending ranges consistently return -EINVAL. This issue was found by a static analysis checker and confirmed by manual source review. Fixes: 94339443686b ("net: bridge: notify on vlan tunnel changes done via the old api") Signed-off-by: Ruoyu Wang <ruoyuw560@gmail.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260814134053.1387275-1-ruoyuw560@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20xsk: fix NULL pointer dereference in __xsk_rcv()Cen Zhang (Microsoft)
In the __xsk_rcv() multi-buffer path, xsk_buff_alloc() is called in a loop without checking its return value. xsk_buff_can_alloc() only counts fill queue entries without validating their addresses, so it can succeed while xsk_buff_alloc() rejects all remaining entries and returns NULL. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000 KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:__xsk_rcv+0x426/0xc20 (net/xdp/xsk.c:350) Call Trace: xsk_generic_rcv+0x26d/0x5f0 xdp_do_generic_redirect+0x3c5/0xcf0 do_xdp_generic+0x92f/0xe70 __netif_receive_skb_core.constprop.0+0xf7e/0x2b30 Fix this with a two-stage transaction. First allocate and stage all buffers required for the packet, recycling all staged buffers with xsk_buff_free() if any allocation fails. Only after this stage succeeds, copy the data, reserve the RX descriptors, and release the buffers in an error-free loop. Fixes: 804627751b42 ("xsk: add support for AF_XDP multi-buffer on Rx path") Reported-by: AutonomousCodeSecurity@microsoft.com Signed-off-by: Cen Zhang (Microsoft) <blbllhy@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Link: https://patch.msgid.link/20260813215328.99311-1-blbllhy@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-20Merge tag 'sysctl-7.03-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl Pull sysctl updates from Joel Granados: - Fix kernel-doc warnings by adjusting in file documentation - Consolidate do_proc_* function into do_proc_vec Consolidate three slightly different implementations of applying a converter on all elements of a vector. Fixes to this function now propagate to the three types. - Replace CONFIG_PROC_SYSCTL with CONFIG_SYSCTL (they were the same) and restrict cad_pid modifications to global root (GLOBAL_ROOT_UID) * tag 'sysctl-7.03-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl: sysctl: remove CONFIG_PROC_SYSCTL, it just mirrors CONFIG_SYSCTL sysctl: move the "cad_pid" entry from pid_table[] to kern_reboot_table[] sysctl: repair some kernel-doc comments sysctl: add Returns: kernel-doc for all functions sysctl: Update API function documentation sysctl: Rename proc_doulongvec_minmax_conv to proc_doulongvec_conv sysctl: Group proc_handler declarations and document sysctl: Replace do_proc_do{int,ulong,uint}vec with do_proc_vec sysctl: Add negp parameter to douintvec converter functions sysctl: Move default converter assignment out of do_proc_dointvec
2026-08-20Merge tag 'net-next-7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "One of the 'small improvements all over the place' releases for us. It's hard to draw any direct comparisons because summer vacations disrupted our patch processing (and presumably - generation) quite a bit. Quick and dirty count suggests we (Paolo and I) merged a very similar number of net (632) and net-next (648) patches. This is not telling the full story either because 1/3 to 1/2 of the net-next patches also *seem* like AI-driven low priority fixes, cleanups and clarifications. We are completely overwhelmed, of course. The glimmer of hope is that we secured sufficient LLM budget and access (thank you Meta!) to run reviews with multiple frontier models on each patch. This eliminates some hallucinations. That said, in terms of review, the LLMs can only do so much. The sad truth is that our APIs (especially for rare events like PCIe errors, timeouts etc) have always been racy, and now LLMs don't let us ignore that. I expect our direction for the next release will be to tweak the reviews a little bit more, but start shifting focus to letting the LLMs take care of the busy work - managing patchwork, automating common process complaints, editing commit messages, and maybe applying patches which already got "reviewed-by" tags from people we trust... Core & protocols: - A few steps lowering rtnl_lock dependence: - per-netns netdev unregistration for select SW drivers (e.g. veth, ipvlan, tunnels) - rtnl_lock-less FIB rule changes (RTM_NEWRULE and RTM_DELRULE) - prepare software drivers and TC qdiscs for rtnl_lock-less GET - Support BIG TCP (>64kB TSO) in UDP tunnels (vxlan, geneve) - Support buffers larger than PAGE_SIZE in devmem zero-copy API - Improve MPTCP handling of extreme memory pressure handling, when out-of-order queue had to be pruned - Report the per-group user count via RTM_GETMULTICAST - Expose the route deletion reason in RTM_DELROUTE - Add a SO_RIGHTS_NOTRUNC option to UNIX sockets to enable more useful handling of LSM denials when receiving SCM_RIGHTS messages: instead of truncating the message at the first blocked fd, keep every fd slot and store the LSM errno in the blocked slot - IPv6 Segment Routing - support looking up the post-encap SID (address) in a different/specified routing table - Support PRP RedBox (interlink) creation - Support per-nexthop UDP dst port in VXLAN - Continue converting getsockopt callbacks in a number of protocols to iov_iter Ethernet: - Merge initial CXL support for AMD/Solarflare NICs (shared branch with the CXL tree) - New drivers: - ADIN1140 10BASE-T1S MACPHY - Initial skeleton of Intel iXD and ZTE Dinghai drivers - High-speed NICs: - AMD/Pensando: - support firmware flashing - Cisco (enic): - SR-IOV V2 admin channel and MBOX protocol - Huawei (hns3): - support for ethtool pfc_prevention_tout - nVidia/Mellanox: - support sharing bandwidth control across interfaces of the same device - Marvell (octeontx2-pf): - link RQ page pools to netdev for Netlink stats - Google vNIC: - XDP metadata support for DQ RDA - Microsoft vNIC: - support forcing full-page RX buffers - Other NICs: - Synopsys IP: - eic7700: support for eth1 - Microchip (lan743x): - support for RMII interface - Wangxun: - support for ethtool -G and -C for VFs - add Tx timeout and PCIe error handling - Intel (igb/igc): - RSS key get/set support - support for forcing link speed without auto-negotiation - Switches: - NXP (dpaa2): - support bonding/LAG offload - Mediatek: - mt7530: EN7528 support - initial support for MT7628 - Micrel (ksz8/9): - refactoring work to move towards library model - PTP support for KSZ8463 - nVidia/Mellanox: - support rtnl-lock-less ethtool callbacks - Realtek: - rtl8366rb: use generic RTL83xx code - support SGMII and HSGMII for RTL8367S - PHYs: - Airoha: - EcoNet EN7528 PHY support - DAPU Telecom - DAPU Telecom DAP8211R(I) Gigabit PHY support - Realtek: - support RTL8261C_CG - support RTL8261D Wireless: - nl80211: per-link statistics support for multi-link operation - mac80211: AQL/airtime-fairness support for multicast - Merge Peripheral Authentication Service (PAS) / TEE support for ath12k (shared branch with the firmware/qcom tree) - New drivers: - mm81x for Morse Micro Long-Range S1G devices - nxpwifi for NXP devices (mostly forked off from mwifiex) - Driver changes: - Broadcom (brcmfmac): - DPP support, some Cypress part update - MediaTek (mt76): - mt7928 support - mt7925 NAN support - mt7996 AP powersave improvements - Qualcomm (ath12k): - much kernel infrastructure integration work - AHB platform MultiPD support - Realtek (rt89): - LED support - RTL8922DE support - dual-BT coex for RTL8922D - Intel: - new FW version support Bluetooth: - HCI: add support for Shorter Connection Interval (SCI) feature - af_bluetooth: add minimal context analysis annotations - Driver changes: - Intel: - add Bluetooth SAR revision 2 support - add vendor_reset PCI sysfs for PLDR - Mediatek: - add USB IDs for MT7902 and MT7922 devices - Realtek: - add USB IDs for 8761CU and 8852BE devices - NXP: - add M.2 Bluetooth device support using pwrseq Misc: - DPLL support for manual/numerical oscillator control (NCO) (implement in zl3073x) - MCTP support for MCTP over USB v1.1 (DMTF DSP0283) - Power-over-Ethernet: support Realtek PSE controllers - Remove the IBM EHEA driver - Remove tulip/xircom_cb driver" * tag 'net-next-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1433 commits) net/mlx5e: do not HW-GRO coalesce small frames net: openvswitch: fix nf_connlabels leak in ovs_ct_init net: add missing ref_tracker_dir_exit() to alloc_netdev_mqs() net: openvswitch: fix flow mask use-after-free on flow deletion sctp: stop processing a packet once its association is deleted dpll: zl3073x: add PTP clock support dpll: zl3073x: add channel ToD, phase step and TIE operations dpll: zl3073x: scale poll interval proportionally to timeout ptp: vmclock: prevent read-only mappings from becoming writable ipv4: reject undersized MTUs in ip_do_fragment() bonding: initialize err for empty target lists net: dsa: initial support for MT7628 embedded switch net: dsa: initial MT7628 tagging driver net: phy: mediatek: add phy driver for MT7628 built-in Fast Ethernet PHYs dt-bindings: net: dsa: add MT7628 ESW net: pse-pd: realtek-pse-mcu: add UART transport net: pse-pd: realtek-pse-mcu: add I2C transport net: pse-pd: add Realtek PSE MCU core dt-bindings: net: pse-pd: add bindings for Realtek PSE MCU vsock: use sock_error() to consume sk_err after a failed connect ...
2026-08-20Merge tag 'bpf-next-7.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Daniel Borkmann: "Major changes: - Redesign the verifier error reporting: failures now carry source and instruction annotations along with the causal event history that led to them, making program rejections far easier to debug and repair (Kumar Kartikeya Dwivedi) - Add arena argument support to kfuncs and struct_ops through the new __arena and __arena__nullable suffixes (Tejun Heo, Puranjay Mohan, Kumar Kartikeya Dwivedi, Ihor Solodrai) - Signed BPF program loader rework to accommodate both BPF and security community needs where the kernel runs the signature verification at BPF_PROG_LOAD time before the LSM admission hook (Daniel Borkmann) - Add a set of ksock kfuncs which let BPF LSM and syscall programs create, connect and send on UDP sockets in order to emit telemetry data (Mahe Tardy) - Unify helper and kfunc call argument verification and classify kfunc arguments purely from BTF into a generated bpf_func_proto which is computed once at add-call time (Amery Hung) Other features and fixes: - Enable EXECMEM_ROX_CACHE for BPF allocations on x86 (Mike Rapoport) - Add bidirectional VLAN support to bpf_fib_lookup() through the new BPF_FIB_LOOKUP_VLAN and BPF_FIB_LOOKUP_VLAN_INPUT flags (Avinash Duduskar) - Infer zext_dst from static register liveness analysis to fix 32-bit zero-extension semantics, and remove the artificial limitations on pointer types eligible for spilling (Eduard Zingerman) - Inline the numeric open-coded iterator kfuncs so that bpf_for() loops no longer pay a kfunc call on every iteration (Puranjay Mohan) - Add an arena-based bitmap data structure to libarena along with serial and parallel selftests (Emil Tsalapatis) - Teach resolve_btfids to discover kfuncs from the kernel's BTF ID sets and to emit kfunc BTF decl tags, reducing the kernel build's dependency on pahole features (Ihor Solodrai) - Add BPF_F_ADJ_ROOM_DECAP_* flags to bpf_skb_adjust_room() so that tunnel decapsulation can update the GSO and encapsulation state of the skb (Nick Hudson) - Fix the ring buffer pending_pos walk and the available-data accounting on 32-bit position wrap (Israel Téllez García) - Add memory usage accounting for arena maps and fix an mmap_lock deadlock on arena lock failure (Jiayuan Chen) - Add tracing_multi link info support to the kernel UAPI and bpftool, and refactor the stack map code to run with preemption disabled (Jiri Olsa) - Support BPF_F_EGRESS in bpf_redirect_peer() to emit the skb in the egress direction of the target's peer device (Jordan Rife) - Add a KF_SPINLOCK_SAFE kfunc flag so that providers, in particular modules, can declare kfuncs safe to call under bpf_spin_lock instead of relying on the verifier's hard-coded allowlist (Kaitao Cheng) - Introduce global percpu data for BPF programs with libbpf probing and bpftool skeleton support, and stop exposing uninitialized kernel heap memory when copying per-CPU map values (Leon Hwang) - Add s390 JIT support for load-acquire and store-release instructions (Maxim Khmelevskii) - Fix a CFI mismatch in the task work callback and an arm64 KASAN false positive after bpf_throw() (Mykyta Yatsenko) - Reject writes through untrusted BTF pointers and bound the rdonly/rdwr_buf_size kfunc arguments (Nicholas Dudar) - Invalidate RCU pointers only after the final spin unlock and account for preempt and IRQ disabled regions as overlapping RCU protection (Ning Ding) - Support mixing bpf2bpf calls and tail calls on RV64, add signed operations and 32-bit atomics to the RV32 JIT, and add timed may_goto support (Pu Lehui, Kuan-Wei Chiu, Feng Jiang) - Fix a use-after-free on mm_struct in bpf_find_vma() for foreign tasks and an mmap_lock leak in the irq_work path (Sanghyun Park) - Populate mmap-able BPF array map memory lazily which makes mmap() O(1) instead of proportional to the map size (Song Liu) - Introduce a jit_required flag and reject programs with inlined helpers when no JIT is available, where the interpreter would otherwise jump into an invalid address (Tiezhu Yang) - Fix the x86 JIT per-CPU address resolution into an extended register where the REX prefix dropped the high destination register bit (Vineet Gupta) - Reject MEM_ALLOC BTF accesses past object bounds, arena frees below the arena base, and mixed arena and ordinary atomic paths (Yiyang Chen) - Fix the trampoline handling of 128-bit arguments and of return values larger than 8 bytes (Yonghong Song) - Ensure that any fault prone load is rewritten with exception table handling, and fix the arena load-acquire and atomic fetch handling in the x86, arm64, riscv and s390 JITs (Daniel Borkmann) - Many more fixes and cleanups across the verifier, arena, trampolines, sockmap, cgroup, ring buffer, x86/arm64/riscv/s390 JITs, libbpf, bpftool, resolve_btfids and selftests" * tag 'bpf-next-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (373 commits) selftests/bpf: Add tests for a store on a fault prone qdisc pointer selftests/bpf: Add tests for fault prone loads out of RCU pointers selftests/bpf: Add tests for pointer type merge at a shared load selftests/bpf: Remove duplicate copies of the arena spinlock qnodes selftests/bpf: Retry stat generation in cgroup_iter_memcg selftests/bpf: Test pseudo-function policy diagnostics bpf: Distinguish function references in policy diagnostics bpf: Preserve source attribution without source text selftests/bpf: Test kfunc argument diagnostics bpf: Correct kfunc argument diagnostics bpf: Use canonical stack argument names in diagnostics bpf: Preserve R0 lineage across helper calls selftests/bpf: Exercise negative optlen in cgroup getsockopt hook bpf: Reject negative optlen in cgroup getsockopt hook selftests/bpf: tc_tunnel - validate decap GSO and encapsulation state bpf: Clear decap state on skb_adjust_room shrink path bpf: Allow new DECAP flags and add guard rails bpf: Add BPF_F_ADJ_ROOM_DECAP_* flags for tunnel decapsulation bpf: Refactor masks for ADJ_ROOM flags and encap validation bpf: Name the enum for BPF_FUNC_skb_adjust_room flags ...
2026-08-19vsock/virtio: restore msg_iter on transmission failureOctavian Purdila
When transmission fails in virtio_transport_send_pkt_info, the msg_iter might have been partially advanced. If we don't restore it, the next attempt to send data will use an incorrect iterator state, leading to desync and warnings like "send_pkt() returns 0, but X expected". Specifically, this can happen in the following scenario, triggered by the syzkaller repro: 1. A write-only VMA (PROT_WRITE only) is partially populated by a prior TUN write that failed with -EIO but still faulted in some pages). 2. A vsock sendmmsg call with MSG_ZEROCOPY requests transmission of a buffer from this VMA. 3. The first packet (64KB) is sent successfully because the pages are populated. 4. The second packet allocation fails because GUP fast pins the first page but GUP slow fails on the next unpopulated page due to PROT_WRITE-only permissions. 5. The iterator is advanced by the partially successful GUP (68KB total advanced: 64KB from first packet + 4KB from second), but the send loop breaks and only reports 64KB sent. This creates a 4KB desync. 6. The next retry starts with a non-zero iov_offset, disabling zerocopy and falling back to copy mode. 7. In copy mode, the transmission succeeds for the next packets but exhausts the iterator early because of the desync. 8. The final retry sees an empty iterator but zerocopy is re-enabled (offset resets). It attempts to send the remaining bytes with zerocopy but pins 0 pages, creating an empty packet. 9. The transport sends the empty packet, triggering the warning because the returned bytes (header only) do not match the expected payload size. 10. The loop continues to spin, allocating ubuf_info each time, eventually exhausting sysctl_optmem_max and returning -ENOMEM to userspace. Restore msg_iter to its original state before the packet allocation and transmission attempt if they fail. Fixes: e0718bd82e27 ("vsock: enable setting SO_ZEROCOPY") Reported-by: syzbot+28e5f3d207b14bae122a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=28e5f3d207b14bae122a Assisted-by: gemini:gemini-3.1-pro Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Octavian Purdila <tavip@google.com> Message-ID: <20260622222757.2130402-3-tavip@google.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2026-08-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Merge in late fixes in preparation for the net-next PR. Conflicts: drivers/dpll/dpll_core.c drivers/dpll/dpll_netlink.c 33f016b23a219 ("dpll: fix NULL deref in dpll_device_ops() during teardown race") b1d0c412088e3 ("dpll: add STATE_CONNECTED_OVERRIDE pin capability") https://lore.kernel.org/aoR9YYY2P5--3x0N@sirena.org.uk https://lore.kernel.org/aoR9VmKllVGwmQn_@sirena.org.uk No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-18net: openvswitch: fix nf_connlabels leak in ovs_ct_initRuoyu Wang
ovs_ct_init() acquires a connlabels reference before initializing the conntrack limit state. If ovs_ct_limit_init() fails, its error is returned directly. The pernet core does not invoke the exit callback for the operation whose initialization failed, so ovs_ct_exit() cannot drop the reference. This leaves labels_used elevated when Open vSwitch pernet registration fails for an existing network namespace. Subsequent conntrack entries in that namespace may allocate label extensions even though Open vSwitch failed to register. Drop the connlabels reference before returning a conntrack limit initialization error. ovs_ct_limit_init() already releases its partial state, and the original error remains unchanged. This issue was found by a static analysis checker and confirmed by manual source review. Fixes: 11efd5cb04a1 ("openvswitch: Support conntrack zone limit") Cc: stable@vger.kernel.org Signed-off-by: Ruoyu Wang <ruoyuw560@gmail.com> Reviewed-by: Ilya Maximets <i.maximets@ovn.org> Link: https://patch.msgid.link/20260815151729.3757984-1-ruoyuw560@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-18net: add missing ref_tracker_dir_exit() to alloc_netdev_mqs()Tetsuo Handa
sashiko is reporting that trying to read /sys/kernel/debug/ref_tracker/* causes use-afer-free crash when either alloc_percpu() or dev_addr_init() in alloc_netdev_mqs() failed, for commit 4d92b95ff2f9 ("net: add net device refcount tracker infrastructure") added ref_tracker_dir_exit() to only free_netdev() path. Closes: https://sashiko.dev/#/patchset/56c707e7-1fb0-43ec-b8fb-cf6f451e513e%40I-love.SAKURA.ne.jp Fixes: 4d92b95ff2f9 ("net: add net device refcount tracker infrastructure") Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/b06ce35d-e7bc-47a5-8e0a-e82be7e4dd08@I-love.SAKURA.ne.jp Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-18net: openvswitch: fix flow mask use-after-free on flow deletionIlya Maximets
The commit in the Fixes tag below made so flow->mask free is scheduled via RCU right after it is removed from the flow table. The pointer stays in the flow structure and it can be accessible while in the same RCU critical section. This is done to avoid requiring ovs_mutex for the ovs_flow_free(). However, while removing the flow during processing of CMD_DEL, we do not take RCU read lock before the removal, and ovs_flow_cmd_fill_info() uses the flow->mask pointer afterwards. The RCU read lock is taken, but it's already late at that point. The comment on that line acknowledges that the lock is cosmetic and doesn't serve a real purpose. This leads to use-after-free if the RCU grace period passes between removal and the filling. It is a short race window, but it is there and can lead to a real crash in case memory allocation for the info takes a bit longer: BUG: KASAN: slab-use-after-free in __ovs_nla_put_key net/openvswitch/flow_netlink.c:1996 BUG: KASAN: slab-use-after-free in ovs_nla_put_key+0x2463/0x2e30 net/openvswitch/flow_netlink.c:2250 Read of size 4 at addr ffff88801ee89970 by task ovs_flow_del_ec/9487 Call Trace: <TASK> __ovs_nla_put_key net/openvswitch/flow_netlink.c:1996 ovs_nla_put_key+0x2463/0x2e30 net/openvswitch/flow_netlink.c:2250 ovs_flow_cmd_fill_info+0x420/0x9c0 net/openvswitch/datapath.c:930 ovs_flow_cmd_del+0x53a/0x970 net/openvswitch/datapath.c:1467 ... netlink_rcv_skb+0x156/0x420 net/netlink/af_netlink.c:2556 </TASK> Allocated by task 9487: mask_alloc net/openvswitch/flow_table.c:967 flow_mask_insert net/openvswitch/flow_table.c:1012 ovs_flow_tbl_insert+0xea2/0x1a90 net/openvswitch/flow_table.c:1084 ovs_flow_cmd_new+0x7e3/0xd90 net/openvswitch/datapath.c:1086 ... netlink_rcv_skb+0x156/0x420 net/netlink/af_netlink.c:2556 Freed by task 9485: rcu_free_sheaf+0x1e/0x100 mm/slub.c:5978 rcu_do_batch kernel/rcu/tree.c:2645 rcu_core+0x59c/0x10c0 kernel/rcu/tree.c:2897 handle_softirqs+0x1e4/0x9a0 kernel/softirq.c:622 ... instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 ovs_flow_tbl_remove() must be called after the ovs_flow_cmd_fill_info() to avoid this race. This also helps with cleaning up the forced cast and the cosmetic RCU read lock. Before the commit in the Fixes tag the order did not matter as long as the flow object itself was not freed. A wider RCU critical section could be another option, but we have a GFP_KERNEL allocation in the way. Reported by Trend Micro's Zero Day Initiative as ZDI-CAN-32042. Fixes: 56c19868e115 ("openvswitch: Make flow mask removal symmetric.") Cc: stable@vger.kernel.org Signed-off-by: Ilya Maximets <i.maximets@ovn.org> Reviewed-by: Aaron Conole <aconole@redhat.com> Link: https://patch.msgid.link/20260815005915.1097270-1-i.maximets@ovn.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-18sctp: stop processing a packet once its association is deletedHyunwoo Kim
sctp_endpoint_bh_rcv() looks the association up only when chunk->asoc is NULL, and caches the result in chunk->asoc and chunk->transport without taking a reference. A packet that matches no association is handed to the endpoint, so a peer can bundle COOKIE ECHO, SHUTDOWN and SHUTDOWN ACK in one packet. The COOKIE ECHO creates the association, the SHUTDOWN chunk caches it, and with the outqueue empty the SHUTDOWN ACK reaches sctp_sf_do_9_2_final(), so the association and its transports are freed. The endpoint loop has no counterpart to the asoc->base.dead check in sctp_assoc_bh_rcv(). The next chunk writes to last_time_heard in the freed transport and is then passed to sctp_do_sm() with the freed association. The transport is freed through RCU, so this needs the packet to come off the socket backlog, where the loop runs in task context. The endpoint loop cannot do the same check: it holds no reference on the association, so reading asoc->base.dead would itself be a use-after-free. Mark the packet for discard in the command interpreter, just before it deletes the association. That is also before sctp_inq_free() releases the chunk on the association receive path. sctp_sf_do_5_2_4_dupcook() issues SCTP_CMD_DELETE_TCB for the temporary association, while the one the packet belongs to stays alive. A restarting peer can bundle DATA behind its COOKIE ECHO, so compare against chunk->asoc and leave that case alone. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/an-YYtoqw1QpTXUL@v4bel Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-18ipv4: reject undersized MTUs in ip_do_fragment()Yong Wang
ip_do_fragment() subtracts the IPv4 header length from the effective MTU and passes the resulting payload MTU to ip_frag_next(). If the effective MTU is smaller than hlen + 8, ip_frag_next() rounds the fragment payload length down to zero. The fragmentation state then never makes forward progress: state->left, state->ptr and state->offset stay unchanged while ip_do_fragment() keeps allocating and transmitting header-only fragments until the softlockup detector fires. This is reproducible with a route installed using "mtu lock 20", but it is also reproducible without route MTU lock, for example by forwarding a packet to a device whose MTU is 20. Fix it in ip_do_fragment() by rejecting mtu < hlen + 8 with -EMSGSIZE, matching the existing IPv6 fragmentation check. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Yong Wang <edragain@163.com> Signed-off-by: Ren Wei <weir@nebusec.ai> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/8809ef6314b98913681b0b370a05a85c2b6cd579.1786599079.git.edragain@163.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-18net: dsa: initial MT7628 tagging driverJoris Vaisvila
Add support for the MT7628 embedded switch's tag. The MT7628 tag is merged with the VLAN TPID field when a VLAN is appended by the switch hardware. It is not installed if the VLAN tag is already there on ingress. Due to this hardware quirk the tag cannot be trusted for port 0 if we don't know that the VLAN was added by the hardware. As a workaround for this the switch is configured to always append the port PVID tag even if the incoming packet is already tagged. The tagging driver can then trust that the tag is always accurate and the whole VLAN tag can be removed on ingress as it's only metadata for the tagger. On egress the MT7628 tag allows precise TX, but the correct VLAN tag from tag_8021q is still appended or the switch will not forward the packet. Signed-off-by: Joris Vaisvila <joey@tinyisr.com> Link: https://patch.msgid.link/20260813190241.789323-4-joey@tinyisr.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18vsock: use sock_error() to consume sk_err after a failed connectNguyen Dinh Phi
vsock_connect() returns sk_err to userspace but does not clear it: if (sk->sk_err) { err = -sk->sk_err; For a blocking connect() the error has already been delivered as connect()'s return value, so leaving it set causes subsequent operations like poll()/epoll() to keep reporting POLLERR even though the connect failure was already delivered. The error should be consumed once it has been returned to userspace. Switch to sock_error(), which reads and clears sk_err atomically, matching the behavior of other protocol implementations such as __inet_stream_connect(). Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Tested-by: Wupeng Ma <mawupeng1@huawei.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com> Link: https://patch.msgid.link/20260813173024.2362935-4-phind.uet@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18vsock: remove the now-unused rejected flagNguyen Dinh Phi
After previous patch, the branch marking a socket rejected in vsock_accept() is unreachable, and nothing ever sets vsk->rejected elsewhere. In fact, since commit d021c344051a ("VSOCK: Introduce VM Sockets"), where `rejected` was introduced, there has never been a path that sets sk_err on a listening socket, so that branch has been dead code since the beginning. Therefore, we can remove the `rejected` field from vsock_sock structure. Suggested-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260813173024.2362935-3-phind.uet@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18vsock: don't check the listener's sk_err in vsock_accept()Nguyen Dinh Phi
Syzbot reported an issue which can be reproduced with these steps: r0 = socket(AF_VSOCK, SOCK_STREAM, 0) bind(r0, {VMADDR_CID_ANY, PORT}) connect(r0, {VMADDR_CID_LOCAL, PORT}) -> -1, EPROTO (self-connect) listen(r0, backlog) -> 0 r1 = socket(AF_VSOCK, SOCK_STREAM, 0) connect(r1, {VMADDR_CID_LOCAL, PORT}) -> 0 accept(r0) -> -1, EPROTO (stale sk_err) Basically, it creates a socket (r0) and triggers a self-connect after binding it. This self-connect fails with EPROTO because it loops back to r0 while the socket is still in the TCP_SYN_SENT state, causing it to be incorrectly dispatched to the connecting-client path. The unexpected packet type encountered there sets sk_err to EPROTO. After that, it invokes a listen() call on the same socket. This listen() call succeeds because the kernel's listening path never inspects or clears sk_err. Then, a new socket (r1) is created as a normal client and connects to r0. However, vsock_accept() rejects this incoming connection because the listener's sk_err still holds the EPROTO error from the earlier failed self-connect. This rejection causes the child socket created for r1's connection to never be freed on virtio or hyperv transports; only the VMCI transport implements pending_work to revisit and clean up a rejected socket. For a non-blocking connect(), vsock_connect() may return -EINPROGRESS immediately, and vsock_connect_timeout() can later set sk->sk_err asynchronously. Since no vsock transport ever sets sk_err on a socket while it is in TCP_LISTEN state, checking it in vsock_accept() serves no purpose and only carries forward errors left behind by earlier, unrelated connection attempts on the same socket. Remove the checks so accept() no longer rejects valid incoming connections because of a stale error, which also avoids the resource leak described above. Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Reported-by: syzbot+1b2c9c4a0f8708082678@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=1b2c9c4a0f8708082678 Suggested-by: Michal Luczaj <mhal@rbox.co> Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260813173024.2362935-2-phind.uet@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18net: ip_tunnel: remove unused non-strict __ip_tunnel_change_mtuIlya Maximets
The last user of this function was the recently removed vport-gre module from openvswitch. Let's drop the function. All other modules use the strict variant. Signed-off-by: Ilya Maximets <i.maximets@ovn.org> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260815001942.1089545-1-i.maximets@ovn.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18ip: orphan prefetched skbs before multicast forwardingZhiling Zou
IPv4 and IPv6 input preserve an skb->sk association installed by bpf_sk_assign() so that local delivery can use the selected socket under RCU. Both address families can also prefetch a socket in UDP early demux. In both paths (BPF and UDP early demux) a reference is not guaranteed to be held on the socket. When a multicast packet is not locally deliverable, IPv6 hands the original skb to ip6_mr_input(). IPv4's ip_mr_input() similarly keeps the original skb when local delivery is not needed. Either path can put the skb on an unresolved multicast route queue or forward it after the receive-side RCU section ends. After the prefetched socket is destroyed, a later skb free invokes sock_pfree() and dereferences the stale skb->sk. Orphan the skb before each non-local multicast forwarding path. Local delivery retains the original skb; the existing skb_clone() calls provide multicast forwarding with a socket-free clone. Fixes: cf7fbe660f2d ("bpf: Add socket assign support") Fixes: 08842c43d016 ("udp: no longer touch sk->sk_refcnt in early demux") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai> Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/0c52eb3d7532aaf8bccf37e0f7c922143c639735.1786552223.git.zhilinz@nebusec.ai Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18net: cap advertised IP tunnel headroomZhiling Zou
IP tunnel devices derive their advertised needed_headroom from lower output devices. A stack of user-created devices can make the derived value larger than the 16-bit skb header offsets can represent. Once IP output reserves it, skb head expansion can wrap those offsets. The runtime transmit path already caps a growing needed_headroom at 512. Apply the same cap when tunnel configuration publishes needed_headroom derived from a lower output device. Capping the advertised value is safe: IP tunnel transmit still expands the skb when a packet needs more headroom. A nonsensical stacked configuration can therefore incur an extra reallocation, but it cannot publish an unbounded reservation to upper layers. Fixes: 1a37e412a022 ("net: Use 16bits for *_headers fields of struct skbuff") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/ba04a1fd6bfae2377607fad5d8f80f7eb80fd4c4.1786542637.git.zhilinz@nebusec.ai Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18ip6_gre: fix hardware header length for NBMA tunnelsZhiling Zou
ip6gre_tnl_link_config_route() accumulates the lower device's hardware header length into dev->hard_header_len whenever header_ops is set. This is incorrect for both users of header_ops. ip6gretap and ip6erspan have a fixed Ethernet hardware header length. For an NBMA ip6gre tunnel, ip6gre_header() creates only the GRE header, the optional FOU or GUE header, and the outer IPv6 header. The lower device header is headroom needed later, not part of the tunnel device's hardware header. Keep the lower device header in needed_headroom. Set hard_header_len to the tunnel header length only for ARPHRD_IP6GRE devices with header_ops, and leave the fixed Ethernet header length unchanged for tap and erspan devices. Fixes: 832ba596494b ("net: ip6_gre: set dev->hard_header_len when using header_ops") Cc: stable@vger.kernel.org Suggested-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/64b46542bbe1701f07702aaa50273e2a87903db5.1786542637.git.zhilinz@nebusec.ai Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-18xfrm: add missing rcu_read_lock(), skb_dst_force() and dev_hold() for ↵Eric Dumazet
xfrm_trans_reinject() syzbot reported a suspicious RCU usage warning in ip6_pkt_drop(): WARNING: suspicious RCU usage in ip6_pkt_drop include/net/addrconf.h:389 suspicious rcu_dereference_check() usage! Call Trace: __in6_dev_get_safely include/net/addrconf.h:389 [inline] ip6_pkt_drop+0x596/0x610 net/ipv6/route.c:4620 ip6_pkt_discard+0x1c/0x30 net/ipv6/route.c:4651 xfrm_trans_reinject+0x324/0x630 net/xfrm/xfrm_input.c:806 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 When commit 4f4920669d21 ("xfrm: Reinject transport-mode packets through workqueue") converted xfrm_trans_reinject from a tasklet to a workqueue, the reinjection loop ceased running in softirq context. Workqueue workers run in process context where local_bh_disable() does not enter an RCU read-side critical section under CONFIG_PREEMPT_RCU. Because finish callbacks (such as ip6_rcv_finish) expect to run under an RCU read lock (performing route lookups, l3mdev lookups, and accessing RCU-protected data structures), invoking them in workqueue context without rcu_read_lock() triggers RCU lockdep warnings. Furthermore, packets queued to the workqueue via xfrm_trans_queue_net() may carry non-refcounted (noref) dst entries (e.g. from ip_route_input_noref). Additionally, on netdevice unregistration, dst_dev_put() replaces dst->dev with blackhole_netdev, so dst entries do not keep skb->dev alive while queued in the workqueue. Fix these issues by: 1. Calling skb_dst_force(skb) in xfrm_trans_queue_net() while still in the caller's RCU section to ensure dst is reference-counted before queuing. 2. Holding a reference on skb->dev via dev_hold()/dev_put() across workqueue deferral so skb->dev remains valid during finish() callback processing. 3. Acquiring rcu_read_lock() around the finish callback invocation loop in xfrm_trans_reinject(). Fixes: 4f4920669d21 ("xfrm: Reinject transport-mode packets through workqueue") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Liu Jian <liujian56@huawei.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2026-08-18xfrm: fix compat ALLOCSPI request use-after-freeKyle Zeng
xfrm_state_netlink() builds the ALLOCSPI response with dump_one_state(), which already calls alloc_compat() with the response skb and header. xfrm_alloc_userspi() then calls alloc_compat() again, but passes the original request skb and its header. For a compat request, the translator therefore interprets the 228-byte compat xfrm_userspi_info as the 232-byte native layout and reads four bytes past the declared payload. It also publishes the translated child through the request's frag_list. A multicast clone of the request shares skb_shared_info and can observe that child. xfrm_user_rcv_msg() frees it after the request handler returns, racing a compat receiver which may still be copying from it and resulting in a use-after-free. Remove the redundant conversion. The response keeps its correct compat translation from dump_one_state(), and no child is attached to the inbound request. Fixes: 5f3eea6b7e8f ("xfrm/compat: Attach xfrm dumps to 64=>32 bit translator") Assisted-by: Codex:gpt-5.6-sol Codex:gpt-5.5-cyber Signed-off-by: Kyle Zeng <kylebot@openai.com> Co-developed-by: David Lee <david.lee@trailofbits.com> Signed-off-by: David Lee <david.lee@trailofbits.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>