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6 daysnet: guard timestamp cmsgs to real error queue skbsKyle Zeng1-3/+3
skb_is_err_queue() treats PACKET_OUTGOING as the sole marker for an skb from sk_error_queue. That assumption is not true for AF_PACKET sockets: outgoing packet taps are also delivered to packet sockets with skb->pkt_type == PACKET_OUTGOING, but their skb->cb is owned by AF_PACKET instead of struct sock_exterr_skb. If such an skb is received with timestamping enabled, the generic timestamp cmsg path can read AF_PACKET control-buffer state as sock_exterr_skb::opt_stats. With SO_RXQ_OVFL enabled, the packet drop counter overlaps opt_stats. An odd drop count makes the path emit SCM_TIMESTAMPING_OPT_STATS with skb->len and skb->data. For non-linear skbs this copies past the linear head and can trigger hardened usercopy or disclose adjacent heap contents. Keep skb_is_err_queue() local to net/socket.c, but make it verify that the PACKET_OUTGOING marker is paired with the sock_rmem_free destructor installed by sock_queue_err_skb(). AF_PACKET receive skbs use normal receive ownership and no longer pass as error-queue skbs, while legitimate sk_error_queue entries keep the PACKET_OUTGOING marker and sock_rmem_free ownership. Fixes: 8605330aac5a ("tcp: fix SCM_TIMESTAMPING_OPT_STATS for normal skbs") Signed-off-by: Kyle Zeng <kylebot@openai.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260607021819.49698-1-kylebot@openai.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daysnetdev: fix double-free in netdev_nl_bind_rx_doit()Jakub Kicinski1-3/+1
Sashiko flags that genlmsg_reply() always consumes the skb. The error path calls nlmsg_free(rsp) so we can't jump directly to it. Let's not unbind, just propagate the error to the user. This is the typical way of handling genlmsg_reply() failures. They shouldn't happen unless user does something silly like calling the kernel with an already-full rcvbuf. Reported-by: Sashiko <sashiko-bot@kernel.org> Fixes: 170aafe35cb9 ("netdev: support binding dma-buf to netdevice") Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daysnet: add pskb_may_pull() to skb_gro_receive_list()HanQuan1-0/+5
skb_gro_receive_list() calls skb_pull(skb, skb_gro_offset(skb)) without first ensuring the data is in the linear area via pskb_may_pull(). When the skb arrives via napi_gro_frags(), skb_headlen can be 0 (all data in page fragments) while skb_gro_offset is non-zero (after IP+TCP header parsing). The skb_pull() then decrements skb->len by skb_gro_offset but skb->data_len stays unchanged, hitting BUG_ON(skb->len < skb->data_len) in __skb_pull(). The UDP fraglist GRO path already contains this guard at udp_offload.c:749. Adding it to skb_gro_receive_list() itself provides centralized protection for all callers (TCP, UDP, and any future protocols), and ensures the precondition of skb_pull() is satisfied before it is called. On pskb_may_pull() failure, set NAPI_GRO_CB(skb)->flush = 1 so the skb is not held as a new GRO head and is instead delivered through the normal receive path, matching the UDP handling. Fixes: 8d95dc474f85 ("net: add code for TCP fraglist GRO") Reported-by: HanQuan <eilaimemedsnaimel@gmail.com> Reported-by: MingXuan <bwnie0730@outlook.com> Signed-off-by: HanQuan <eilaimemedsnaimel@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daystcp: restrict SO_ATTACH_FILTER to priv usersEric Dumazet1-0/+5
This patch restricts the use of SO_ATTACH_FILTER (cBPF) on TCP sockets to users with CAP_NET_ADMIN capability. This blocks potential side-channel attack where an unprivileged application attaches a filter to leak TCP sequence/acknowledgment numbers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Tamir Shahar <tamirthesis@gmail.com> Reported-by: Amit Klein <aksecurity@gmail.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com> Cc: Song Liu <song@kernel.org> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Stanislav Fomichev <sdf@fomichev.me> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
13 daysnet: Annotate sk->sk_write_space() for UDP SOCKMAP.Kuniyuki Iwashima1-2/+6
UDP TX skb->destructor() is sock_wfree(), and UDP holds lock_sock() only for UDP_CORK / MSG_MORE sendmsg(). Otherwise, sk->sk_write_space() may be read locklessly while SOCKMAP rewrites sk->sk_write_space(). Let's use WRITE_ONCE() and READ_ONCE() for sk->sk_write_space(). Note that the write side is annotated by commit 2ef2b20cf4e0 ("net: annotate data-races around sk->sk_{data_ready,write_space}"). Fixes: 7b98cd42b049 ("bpf: sockmap: Add UDP support") Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://patch.msgid.link/20260529193941.3897256-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-29net: skbuff: fix pskb_carve leaking zcopy pagesPavel Begunkov1-0/+10
When SKBFL_MANAGED_FRAG_REFS is set, frag pages are not refcounted but their lifetime is controlled by the attached ubuf_info. To make a copy of the skb_shared_info, we either should clear the flag and reference the frags, or keep the flag and have frags unreferenced. pskb_carve_inside_header() and pskb_carve_inside_nonlinear() don't follow the rule and thus can leak page references. Let's clear SKBFL_MANAGED_FRAG_REFS from the original skb to fix it. It's the simplest way to address it, but there are more performant ways to do that if it ever becomes a problem. Link: https://lore.kernel.org/all/20260523085809.26331-1-nvminh232@clc.fitus.edu.vn/ Fixes: 753f1ca4e1e50 ("net: introduce managed frags infrastructure") Reported-by: Minh Nguyen <minhnguyen.080505@gmail.com> Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/1e2086aa69217d7f9c8da3d38f5be7160f1b4cd1.1779993185.git.asml.silence@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-29bpf: sockmap: fix tail fragment offset in bpf_msg_push_dataYuqi Xu1-1/+1
When bpf_msg_push_data() inserts data in the middle of a scatterlist entry, it splits the original entry into a left fragment and a right fragment. The right fragment offset is page-local, but the code advances it with `start`, which is the message-global insertion point. For inserts into a non-first SG entry, this over-advances the offset and leaves the split layout inconsistent. Advance the right fragment offset by the fragment-local delta, `start - offset`, which matches the length removed from the front of the original entry. Fixes: 6fff607e2f14 ("bpf: sk_msg program helper bpf_msg_push_data") Cc: stable@kernel.org Reported-by: Yuan Tan <yuantan098@gmail.com> Reported-by: Zhengchuan Liang <zcliangcn@gmail.com> Reported-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Yuqi Xu <xuyq21@lenovo.com> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Link: https://patch.msgid.link/8b129d10566aa3eb43f61a8f9757bcf51707d324.1779636774.git.xuyq21@lenovo.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-28Merge tag 'net-7.1-rc6' of ↵Linus Torvalds1-4/+31
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "This is again significantly bigger than the same point into the previous cycle, but at least smaller than last week. I'm not aware of any pending regression for the current cycle. Including fixes from netfilter. Current release - regressions: - netfilter: walk fib6_siblings under RCU Previous releases - regressions: - netlink: fix sending unassigned nsid after assigned one - bridge: fix sleep in atomic context in netlink path - sched: fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop - ipv4: fix net->ipv4.sysctl_local_reserved_ports UaF - eth: tun: free page on short-frame rejection in tun_xdp_one() Previous releases - always broken: - skbuff: fix missing zerocopy reference in pskb_carve helpers - handshake: drain pending requests at net namespace exit - ethtool: - rss: avoid modifying the RSS context response - module: avoid leaking a netdev ref on module flash errors - coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES - netfilter: fix dst corruption in same register operation - nfc: hci: fix out-of-bounds read in HCP header parsing - ipv6: exthdrs: refresh nh pointer after ipv6_hop_jumbo() - eth: - vti: use ip6_tnl.net in vti6_changelink(). - vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()" * tag 'net-7.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (94 commits) dpll: zl3073x: make frequency monitor a per-device attribute dpll: zl3073x: use __dpll_device_change_ntf() and remove change_work dpll: export __dpll_device_change_ntf() for use under dpll_lock net/handshake: Drain pending requests at net namespace exit net/handshake: Verify file-reference balance in submit paths net/handshake: Close the submit-side sock_hold race net/handshake: hand off the pinned file reference to accept_doit net/handshake: Take a long-lived file reference at submit net/handshake: Pass negative errno through handshake_complete() nvme-tcp: store negative errno in queue->tls_err net/handshake: Use spin_lock_bh for hn_lock net: skbuff: fix missing zerocopy reference in pskb_carve helpers net: hibmcge: move dma_rmb() after dma_sync_single_for_cpu() in RX path net: hibmcge: disable Relaxed Ordering to fix RX packet corruption selftests/tc-testing: Add netem test case exercising loops selftests/tc-testing: Add mirred test cases exercising loops net/sched: act_mirred: Fix return code in early mirred redirect error paths net/sched: act_mirred: Fix blockcast recursion bypass leading to stack overflow net/sched: Fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop net/sched: fix packet loop on netem when duplicate is on ...
2026-05-28net: skbuff: fix missing zerocopy reference in pskb_carve helpersMinh Nguyen1-0/+4
pskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy the old skb_shared_info header into a new buffer via memcpy(), which includes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs. Neither function calls net_zcopy_get() for the new shinfo, creating an unaccounted holder: every skb_shared_info with destructor_arg set will call skb_zcopy_clear() once when freed, but the corresponding net_zcopy_get() was never called for the new copy. Repeated calls drive uarg->refcnt to zero prematurely, freeing ubuf_info_msgzc while TX skbs still hold live destructor_arg pointers. KASAN reports use-after-free on a freed ubuf_info_msgzc: BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810 Read of size 8 at addr ffff88801574d3e8 by task poc/220 Call Trace: skb_release_data+0x77b/0x810 kfree_skb_list_reason+0x13e/0x610 skb_release_data+0x4cd/0x810 sk_skb_reason_drop+0xf3/0x340 skb_queue_purge_reason+0x282/0x440 rds_tcp_inc_free+0x1e/0x30 rds_recvmsg+0x354/0x1780 __sys_recvmsg+0xdf/0x180 Allocated by task 219: msg_zerocopy_realloc+0x157/0x7b0 tcp_sendmsg_locked+0x2892/0x3ba0 Freed by task 219: ip_recv_error+0x74a/0xb10 tcp_recvmsg+0x475/0x530 The skb consuming the late access still referenced the same uarg via shinfo->destructor_arg copied by pskb_carve_inside_nonlinear() without a refcount bump. This has been verified to be reliably exploitable: a working proof-of-concept achieves full root privilege escalation from an unprivileged local user on a default kernel configuration. The fix follows the pattern of pskb_expand_head() which has the same memcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get() is placed after skb_orphan_frags() succeeds, so the orphan error path needs no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is placed after all failure points and just before skb_release_data(), so no error path needs cleanup at all -- matching pskb_expand_head() more closely and avoiding the need for a balancing net_zcopy_put(). Fixes: 6fa01ccd8830 ("skbuff: Add pskb_extract() helper function") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-sonnet-4-6 Signed-off-by: Minh Nguyen <minhnguyen.080505@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260526041240.329462-1-minhnguyen.080505@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-05-26Merge tag 'mm-hotfixes-stable-2026-05-25-16-22' of ↵Linus Torvalds2-32/+15
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "13 hotfixes. 9 are for MM. 9 are cc:stable and the remaining 4 address post-7.1 issues or aren't considered suitable for backporting. All patches are singletons - please see the individual changelogs for details" * tag 'mm-hotfixes-stable-2026-05-25-16-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: Revert "mm: introduce a new page type for page pool in page type" mm/vmalloc: do not trigger BUG() on BH disabled context MAINTAINERS, mailmap: change email for Eugen Hristev mm/migrate_device: fix pgtable leak in migrate_vma_insert_huge_pmd_page kernel/fork: validate exit_signal in kernel_clone() mm: memcontrol: propagate NMI slab stats to memcg vmstats mm/damon/sysfs-schemes: delete tried region in regions_rmdirs() mm/rmap: initialize nr_pages to 1 at loop start in try_to_unmap_one zram: fix use-after-free in zram_writeback_endio memfd: deny writeable mappings when implying SEAL_WRITE ipc: limit next_id allocation to the valid ID range Revert "mm/hugetlbfs: update hugetlbfs to use mmap_prepare" MAINTAINERS: .mailmap: update after GEHC spin-off
2026-05-26net: Avoid checksumming unreadable skb tail on trimBjörn Töpel1-4/+27
pskb_trim_rcsum_slow() keeps CHECKSUM_COMPLETE valid by subtracting the checksum of the bytes removed from the skb tail. That assumes the removed bytes can be read. io_uring zcrx skbs may contain unreadable net_iov frags. With fbnic header/data split, small TCP/IPv4 packets can carry Ethernet padding in such a frag. ip_rcv_core() trims the skb to iph->tot_len before TCP sees it, and the CHECKSUM_COMPLETE adjustment then calls skb_checksum() on the padding. This is exposed by IPv4 because small TCP/IPv4 frames can be shorter than the Ethernet minimum payload. TCP/IPv6 frames are large enough in the normal zcrx path, so they do not hit the same padding trim. Keep the existing checksum adjustment for readable skbs. If the remaining packet is fully linear, drop CHECKSUM_COMPLETE and let the stack validate the packet after trimming. If unreadable payload would remain, fail the trim; the checksum cannot be adjusted without reading the trimmed tail. Also clear skb->unreadable when trimming removes all frags. Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags") Signed-off-by: Björn Töpel <bjorn@kernel.org> Reviewed-by: Breno Leitao <leitao@debian.org> Link: https://patch.msgid.link/20260522120643.242974-1-bjorn@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-05-22Revert "mm: introduce a new page type for page pool in page type"Byungchul Park2-32/+15
This reverts commit db359fccf212 ("mm: introduce a new page type for page pool in page type") and a part of 735a309b4bfb9e ("net: add net_iov_init() and use it to initialize ->page_type"). Netpp page_type'ed pages might be used in mapping so as to use @_mapcount. However, since @page_type and @_mapcount are union'ed in struct page, these two can't be used at the same time. Revert the commit introducing page_type for Netpp for now. The patch will be retried once @page_type and @_mapcount get allowed to be used at the same time. The revert also includes removal of @page_type initialization part introduced by commit 735a309b4bfb9e ("net: add net_iov_init() and use it to initialize ->page_type"), which will be restored on the retry. Link: https://lore.kernel.org/20260515034701.17027-1-byungchul@sk.com Fixes: db359fccf212 ("mm: introduce a new page type for page pool in page type") Signed-off-by: Byungchul Park <byungchul@sk.com> Reported-by: Dragos Tatulea <dtatulea@nvidia.com> Closes: https://lore.kernel.org/all/982b9bc1-0a0a-4fc5-8e3a-3672db2b29a1@nvidia.com Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Harry Yoo (Oracle) <harry@kernel.org> Reviewed-by: Lorenzo Stoakes <ljs@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org> Cc: Jesper Dangaard Brouer <hawk@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: Liam R. Howlett <liam@infradead.org> Cc: Mark Bloch <mbloch@nvidia.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Pavel Begunkov <asml.silence@gmail.com> Cc: Saeed Mahameed <saeedm@nvidia.com> Cc: Simon Horman <horms@kernel.org> Cc: Stanislav Fomichev <sdf@fomichev.me> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tariq Toukan <tariqt@nvidia.com> Cc: Toke Hoiland-Jorgensen <toke@redhat.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-21net: bridge: prevent too big nested attributes in br_fill_linkxstats()Eric Dumazet1-2/+3
After commit ff205bf8c554 ("netlink: add one debug check in nla_nest_end()") syzbot found that br_fill_linkxstats() can send corrupted netlink packets. Make sure the nested attribute size is bounded. Fixes: a60c090361ea ("bridge: netlink: export per-vlan stats") Reported-by: syzbot+a35f9259d08f907c06e6@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a0b0da3.050a0220.175f0c.0000.GAE@google.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260520114207.1394241-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-21net: gro: don't merge zcopy skbsSabrina Dubroca1-0/+3
skb_gro_receive() can currently copy frags between the source and GRO skb, without checking the zerocopy status, and in particular the SKBFL_MANAGED_FRAG_REFS flag. When SKBFL_MANAGED_FRAG_REFS is set, the skb doesn't hold a reference on the pages in shinfo->frags. Appending those frags to another skb's frags without fixing up the page refcount can lead to UAF. When either the last skb in the GRO chain (the one we would append frags to) or the source skb is zerocopy, don't merge the skbs. Fixes: 753f1ca4e1e5 ("net: introduce managed frags infrastructure") Reported-by: Huzaifa Sidhpurwala <huzaifas@redhat.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/c3b7f906bbfcbdfd7b4fa9d6c18a438870df85be.1779307748.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-21netpoll: normalize skb->dev to the netpoll deviceZhang Cen1-0/+2
__netpoll_send_skb() always transmits through np->dev and queues busy packets on np->dev->npinfo->txq, but it leaves skb->dev unchanged. Stacked callers such as DSA and macvlan can reach netpoll with skb->dev still naming the upper device while np->dev is the lower device that owns the netpoll state. If the skb has to be deferred, queue_process() later dequeues it from the lower device's txq but retries it through skb->dev. That can re-enter the upper ndo_start_xmit path on an already transformed skb, and if the upper device disappears before the lower txq drains the workqueue can dereference a stale skb->dev pointer. The buggy scenario involves two paths, with each column showing the order within that path: path A label: netpoll enqueue path path B label: upper-device teardown 1. Stacked xmit calls netpoll 1. Teardown unregisters the upper with lower np->dev and upper net_device while lower npinfo skb->dev. stays alive. 2. __netpoll_send_skb() uses 2. netdev_release() runs for the np->dev->npinfo as the txq upper net_device. owner. 3. Busy transmit queues the skb 3. The lower txq still owns the on that lower txq with upper deferred skb. skb->dev. 4. queue_process() drains the 4. queue_process() dereferences lower txq and reads skb->dev. that stale upper skb->dev. Normalize skb->dev to np->dev after loading np->dev from the netpoll instance, before either the direct transmit path or the fallback enqueue. This keeps the queued skb in the same device and txq domain as the netpoll state that owns it. KASAN report as below: KASAN slab-use-after-free in queue_process+0x7c/0x480 Workqueue: events queue_process The buggy address belongs to the object at ffff88810906c000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 168 bytes inside of freed 4096-byte region [ffff88810906c000, ffff88810906d000) Read of size 8 Call trace: dump_stack_lvl+0x73/0xb0 (?:?) print_report+0xd1/0x620 (?:?) srso_alias_return_thunk+0x5/0xfbef5 (?:?) __virt_addr_valid+0x215/0x420 (?:?) kasan_complete_mode_report_info+0x64/0x200 (?:?) kasan_report+0xf7/0x130 (?:?) queue_process+0x7c/0x480 (net/core/netpoll.c:88) kasan_check_range+0x10c/0x1c0 (?:?) __kasan_check_read+0x15/0x20 (?:?) process_one_work+0x8b7/0x1af0 (kernel/workqueue.c:3200) assign_work+0x170/0x3f0 (?:?) worker_thread+0x574/0xf10 (?:?) _raw_spin_unlock_irqrestore+0x4b/0x60 (?:?) trace_hardirqs_on+0x2a/0x180 (?:?) kthread+0x2fc/0x3f0 (?:?) ret_from_fork+0x58b/0x830 (?:?) __switch_to+0x58e/0xe90 (?:?) __switch_to_asm+0x39/0x70 (?:?) ret_from_fork_asm+0x1a/0x30 (?:?) Freed by task stack: kasan_save_stack+0x3d/0x60 (?:?) kasan_save_track+0x18/0x40 (?:?) kasan_save_free_info+0x3f/0x60 (?:?) __kasan_slab_free+0x48/0x70 (?:?) kfree+0x20e/0x4e0 (?:?) kvfree+0x31/0x40 (?:?) netdev_release+0x71/0x90 (net/core/net-sysfs.c:2227) device_release+0xd2/0x250 (?:?) kobject_put+0x181/0x4c0 (lib/kobject.c:730) netdev_run_todo+0x700/0x1000 (net/core/dev.c:11666) rtnl_dellink+0x396/0xc00 (net/core/rtnetlink.c:3558) rtnetlink_rcv_msg+0x740/0xc20 (net/core/rtnetlink.c:6897) netlink_rcv_skb+0x147/0x3a0 (?:?) rtnetlink_rcv+0x19/0x20 (net/core/rtnetlink.c:7021) netlink_unicast+0x4d1/0x830 (net/netlink/af_netlink.c:1327) netlink_sendmsg+0x840/0xe10 (net/netlink/af_netlink.c:1812) ____sys_sendmsg+0x8a7/0xb50 (?:?) ___sys_sendmsg+0x104/0x190 (?:?) __sys_sendmsg+0x135/0x1d0 (?:?) __x64_sys_sendmsg+0x7b/0xc0 (?:?) x64_sys_call+0x205c/0x2130 (?:?) do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87) entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?) Fixes: 5de4a473bda4 ("netpoll queue cleanup") Signed-off-by: Zhang Cen <rollkingzzc@gmail.com> Link: https://patch.msgid.link/20260519104647.3517990-1-rollkingzzc@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-21net: skbuff: propagate shared-frag marker through frag-transfer helpersHyunwoo Kim2-1/+12
Two frag-transfer helpers (__pskb_copy_fclone() and skb_shift()) fail to propagate the SKBFL_SHARED_FRAG bit in skb_shinfo()->flags when moving frags from source to destination. __pskb_copy_fclone() defers the rest of the shinfo metadata to skb_copy_header() after copying frag descriptors, but that helper only carries over gso_{size,segs, type} and never touches skb_shinfo()->flags; skb_shift() moves frag descriptors directly and leaves flags untouched. As a result, the destination skb keeps a reference to the same externally-owned or page-cache-backed pages while reporting skb_has_shared_frag() as false. The mismatch is harmful in any in-place writer that uses skb_has_shared_frag() to decide whether shared pages must be detoured through skb_cow_data(). ESP input is one such writer (esp4.c, esp6.c), and a single nft 'dup to <local>' rule -- or any other nf_dup_ipv4() / xt_TEE caller -- is enough to land a pskb_copy()'d skb in esp_input() with the marker stripped, letting an unprivileged user write into the page cache of a root-owned read-only file via authencesn-ESN stray writes. Set SKBFL_SHARED_FRAG on the destination whenever frag descriptors were actually moved from the source. skb_copy() and skb_copy_expand() share skb_copy_header() too but linearize all paged data into freshly allocated head storage and emerge with nr_frags == 0, so skb_has_shared_frag() returns false on its own; they need no change. The same omission exists in skb_gro_receive() and skb_gro_receive_list(). The former moves the incoming skb's frag descriptors into the accumulator's last sub-skb via two paths (a direct frag-move loop and the head_frag + memcpy path); the latter chains the incoming skb whole onto p's frag_list. Downstream skb_segment() reads only skb_shinfo(p)->flags, and skb_segment_list() reuses each sub-skb's shinfo as the nskb -- both p and lp must carry the marker. The same omission also exists in tcp_clone_payload(), which builds an MTU probe skb by moving frag descriptors from skbs on sk_write_queue into a freshly allocated nskb. The helper falls into the same family and warrants the same fix for consistency; no TCP TX-side in-place writer is currently known to reach a user page through this gap, but a future consumer depending on the marker would regress silently. The same omission exists in skb_segment(): the per-iteration flag merge takes only head_skb's flag, and the inner switch that rebinds frag_skb to list_skb on head_skb-frags exhaustion does not fold the new frag_skb's flag into nskb. Fold frag_skb's flag at both sites so segments drawing frags from frag_list members carry the marker. Fixes: cef401de7be8 ("net: fix possible wrong checksum generation") Fixes: f4c50a4034e6 ("xfrm: esp: avoid in-place decrypt on shared skb frags") Suggested-by: Sabrina Dubroca <sd@queasysnail.net> Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com> Suggested-by: Ben Hutchings <ben@decadent.org.uk> Suggested-by: Lin Ma <malin89@huawei.com> Suggested-by: Jingguo Tan <tanjingguo@huawei.com> Suggested-by: Aaron Esau <aaron1esau@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Tested-by: Rajat Gupta <rajat.gupta@oss.qualcomm.com> Link: https://patch.msgid.link/ageeJfJHwgzmKXbh@v4bel Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-05-21net: devmem: reject dma-buf bind with non-page-aligned size or SG lengthDavid Carlier1-0/+11
net_devmem_bind_dmabuf() trusts dmabuf->size and sg_dma_len() to be PAGE_SIZE multiples without checking: - tx_vec is sized dmabuf->size / PAGE_SIZE, and net_devmem_get_niov_at() only bounds-checks virt_addr < dmabuf->size before indexing tx_vec[virt_addr / PAGE_SIZE]. With size = N*PAGE_SIZE + r (1 <= r < PAGE_SIZE), sendmsg() at iov_base = N*PAGE_SIZE passes the bound check and reads tx_vec[N] -- one past. - owner->area.num_niovs = len / PAGE_SIZE while gen_pool_add_owner() covers the full byte len, so a non-page-multiple non-final sg desyncs num_niovs from the gen_pool region for every later sg, on both RX and TX. dma-buf does not require page-aligned sizes, so the bind path has to enforce what its own indexing assumes. Reject both with -EINVAL. The size check is TX-only (only tx_vec is sized off dmabuf->size); the SG-length check covers both directions. Fixes: bd61848900bf ("net: devmem: Implement TX path") Cc: stable@vger.kernel.org Signed-off-by: David Carlier <devnexen@gmail.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Reviewed-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/20260519203530.66310-1-devnexen@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-21bpf, skmsg: fix verdict sk_data_ready racing with ktls rxXingwang Xiang1-2/+7
sk_psock_strp_data_ready() already checks tls_sw_has_ctx_rx() and defers to psock->saved_data_ready when a TLS RX context is present, avoiding a conflict with the TLS strparser's ownership of the receive queue (commit e91de6afa81c, "bpf: Fix running sk_skb program types with ktls"). sk_psock_verdict_data_ready() has no equivalent guard. When a socket is inserted into a sockmap (BPF_SK_SKB_VERDICT) before TLS RX is configured, tls_sw_strparser_arm() saves sk_psock_verdict_data_ready as rx_ctx->saved_data_ready. On data arrival: tls_data_ready -> tls_strp_data_ready -> tls_rx_msg_ready -> saved_data_ready() = sk_psock_verdict_data_ready() -> tcp_read_skb() drains sk_receive_queue via __skb_unlink() without calling tcp_eat_skb(), so copied_seq is not advanced. tls_strp_msg_load() then finds tcp_inq() >= full_len (stale), calls tcp_recv_skb() on the now-empty queue, hits WARN_ON_ONCE(!first), and returns with rx_ctx->strp.anchor.frag_list pointing at a psock-owned (potentially freed) skb. tls_decrypt_sg() subsequently walks that frag_list: use-after-free. Apply the same fix as sk_psock_strp_data_ready(): if a TLS RX context is present, call psock->saved_data_ready (sock_def_readable) to wake recv() waiters and return immediately, leaving the receive queue untouched. TLS retains sole ownership of the queue and decrypts the record normally through tls_sw_recvmsg(). Fixes: ef5659280eb1 ("bpf, sockmap: Allow skipping sk_skb parser program") Signed-off-by: Xingwang Xiang <v3rdant.xiang@gmail.com> Link: https://patch.msgid.link/20260517145630.20521-2-v3rdant.xiang@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-15net: skbuff: preserve shared-frag marker during coalescingWilliam Bowling1-0/+2
skb_try_coalesce() can attach paged frags from @from to @to. If @from has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same externally-owned or page-cache-backed frags, but the shared-frag marker is currently lost. That breaks the invariant relied on by later in-place writers. In particular, ESP input checks skb_has_shared_frag() before deciding whether an uncloned nonlinear skb can skip skb_cow_data(). If TCP receive coalescing has moved shared frags into an unmarked skb, ESP can see skb_has_shared_frag() as false and decrypt in place over page-cache backed frags. Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged frags. The tailroom copy path does not need the marker because it copies bytes into @to's linear data rather than transferring frag descriptors. Fixes: cef401de7be8 ("net: fix possible wrong checksum generation") Fixes: f4c50a4034e6 ("xfrm: esp: avoid in-place decrypt on shared skb frags") Signed-off-by: William Bowling <vakzz@zellic.io> Reviewed-by: Eric Dumazet <edumazet@google.com> Tested-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260513041635.1289541-1-vakzz@zellic.io Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-14Merge tag 'net-7.1-rc4' of ↵Linus Torvalds2-10/+17
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from netfilter. Previous releases - regressions: - ethtool: fix NULL pointer dereference in phy_reply_size - netfilter: - allocate hook ops while under mutex - close dangling table module init race - restore nf_conntrack helper propagation via expectation - tcp: - fix potential UAF in reqsk_timer_handler(). - fix out-of-bounds access for twsk in tcp_ao_established_key(). - vsock: fix empty payload in tap skb for non-linear buffers - hsr: fix NULL pointer dereference in hsr_get_node_data() - eth: - cortina: fix RX drop accounting - ice: fix locking in ice_dcb_rebuild() Previous releases - always broken: - napi: avoid gro timer misfiring at end of busypoll - sched: - dualpi2: initialize timer earlier in dualpi2_init() - sch_cbs: Call qdisc_reset for child qdisc - shaper: - fix ordering issue in net_shaper_commit() - reject handle IDs exceeding internal bit-width - ipv6: flowlabel: enforce per-netns limit for unprivileged callers - tls: fix off-by-one in sg_chain entry count for wrapped sk_msg ring - smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint - sctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL - batman-adv: - reject new tp_meter sessions during teardown - purge non-released claims - eth: - i40e: cleanup PTP registration on probe failure - idpf: fix double free and use-after-free in aux device error paths - ena: fix potential use-after-free in get_timestamp" * tag 'net-7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (88 commits) net: phy: DP83TC811: add reading of abilities net: tls: prevent chain-after-chain in plain text SG net: tls: fix off-by-one in sg_chain entry count for wrapped sk_msg ring net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot macsec: use rcu_work to defer TX SA crypto cleanup out of softirq macsec: use rcu_work to defer RX SA crypto cleanup out of softirq macsec: introduce dedicated workqueue for SA crypto cleanup net: net_failover: Fix the deadlock in slave register MAINTAINERS: update atlantic driver maintainer selftests/tc-testing: Add QFQ/CBS qlen underflow test net/sched: sch_cbs: Call qdisc_reset for child qdisc FDDI: defza: Sanitise the reset safety timer net: ethernet: ravb: Do not check URAM suspension when WoL is active ethtool: fix ethnl_bitmap32_not_zero() bit interval semantics net/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint net/smc: fix sleep-inside-lock in __smc_setsockopt() causing local DoS net: atm: fix skb leak in sigd_send() default branch net: ethtool: phy: avoid NULL deref when PHY driver is unbound net: atlantic: preserve PCI wake-from-D3 on shutdown when WOL enabled net: shaper: reject QUEUE scope handle with missing id ...
2026-05-14net: net_failover: Fix the deadlock in slave registerFaicker Mo1-1/+5
There is netdev_lock_ops() before the NETDEV_REGISTER notifier in register_netdevice(), so use the non-locking functions in net_failover_slave_register(). failover_slave_register() in failover_existing_slave_register() adds lock and unlock ops too. Call Trace: <TASK> __schedule+0x30d/0x7a0 schedule+0x27/0x90 schedule_preempt_disabled+0x15/0x30 __mutex_lock.constprop.0+0x538/0x9e0 __mutex_lock_slowpath+0x13/0x20 mutex_lock+0x3b/0x50 dev_set_mtu+0x40/0xe0 net_failover_slave_register+0x24/0x280 failover_slave_register+0x103/0x1b0 failover_event+0x15e/0x210 ? dropmon_net_event+0xac/0xe0 notifier_call_chain+0x5e/0xe0 raw_notifier_call_chain+0x16/0x30 call_netdevice_notifiers_info+0x52/0xa0 register_netdevice+0x5f4/0x7c0 register_netdev+0x1e/0x40 _mlx5e_probe+0xe2/0x370 [mlx5_core] mlx5e_probe+0x59/0x70 [mlx5_core] ? __pfx_mlx5e_probe+0x10/0x10 [mlx5_core] Fixes: 4c975fd70002 ("net: hold instance lock during NETDEV_REGISTER/UP") Signed-off-by: Faicker Mo <faicker.mo@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-10Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds3-27/+81
Pull bpf fixes from Alexei Starovoitov: - Fix sk_local_storage diag dump via netlink (Amery Hung) - Fix off-by-one in arena direct-value access (Junyoung Jang) - Reject TCP_NODELAY in bpf-tcp congestion control (KaFai Wan) - Fix type confusion in bpf_*_sock() (Kuniyuki Iwashima) - Reject TX-only AF_XDP sockets (Linpu Yu) - Don't run arg-tracking analysis twice on main subprog (Paul Chaignon) - Fix NULL pointer dereference in bpf_sk_storage_clone and fib lookup (Weiming Shi) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Fix off-by-one boundary validation in arena direct-value access xskmap: reject TX-only AF_XDP sockets bpf: Don't run arg-tracking analysis twice on main subprog bpf: Free reuseport cBPF prog after RCU grace period. bpf: tcp: Fix type confusion in sol_tcp_sockopt(). bpf: tcp: Fix type confusion in bpf_skc_to_tcp6_sock(). bpf: tcp: Fix type confusion in bpf_skc_to_tcp_sock(). mptcp: bpf: Fix type confusion in bpf_mptcp_sock_from_subflow() selftest: bpf: Add test for bpf_tcp_sock() and RAW socket. bpf: tcp: Fix type confusion in bpf_tcp_sock(). tools/headers: Regenerate stddef.h to fix BPF selftests bpf: Fix sk_local_storage diag dumping uninitialized special fields bpf: Fix NULL pointer dereference in bpf_skb_fib_lookup() sockmap: Fix sk_psock_drop() race vs sock_map_{unhash,close,destroy}(). bpf: Fix NULL pointer dereference in bpf_sk_storage_clone and diag paths selftests/bpf: Verify bpf-tcp-cc rejects TCP_NODELAY selftests/bpf: Test TCP_NODELAY in TCP hdr opt callbacks bpf: Reject TCP_NODELAY in bpf-tcp-cc bpf: Reject TCP_NODELAY in TCP header option callbacks
2026-05-09net: napi: Avoid gro timer misfiring at end of busypollDragos Tatulea1-9/+12
When in irq deferral mode (defer-hard-irqs > 0), a short enough gro-flush timeout can trigger before NAPI_STATE_SCHED is cleared if the last poll in busy_poll_stop() takes too long. This can have the effect of leaving the queue stuck with interrupts disabled and no timer armed which results in a tx timeout if there is no subsequent busypoll cycle. To prevent this, defer the gro-flush timer arm after the last poll. Fixes: 7fd3253a7de6 ("net: Introduce preferred busy-polling") Co-developed-by: Martin Karsten <mkarsten@uwaterloo.ca> Signed-off-by: Martin Karsten <mkarsten@uwaterloo.ca> Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com> Reviewed-by: Joe Damato <joe@dama.to> Link: https://patch.msgid.link/20260506090808.820559-2-dtatulea@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-08bpf: Free reuseport cBPF prog after RCU grace period.Kuniyuki Iwashima1-3/+12
Eulgyu Kim reported the splat below with a repro. [0] The repro sets up a UDP reuseport group with a cBPF prog and replaces it with a new one while another thread is sending a UDP packet to the group. The reuseport prog is freed by sk_reuseport_prog_free(). bpf_prog_put() is called for "e"BPF prog to destruct through multiple stages while cBPF prog is freed immediately by bpf_release_orig_filter() and bpf_prog_free(). If a reuseport prog is detached from the setsockopt() path (reuseport_attach_prog() or reuseport_detach_prog()), sk_reuseport_prog_free() is called without waiting for RCU readers to complete, resulting in various bugs. Let's defer freeing the reuseport cBPF prog after one RCU grace period. Note "e"BPF prog is safe as is unless the fast path starts to touch fields destroyed in bpf_prog_put_deferred() and __bpf_prog_put_noref(). [0]: BUG: KASAN: vmalloc-out-of-bounds in reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596 Read of size 4 at addr ffffc9000051e004 by task slowme/10208 CPU: 6 UID: 1000 PID: 10208 Comm: slowme Not tainted 7.0.0-geb7ac95ff75e #32 PREEMPT(full) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <IRQ> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596 udp4_lib_lookup2+0x3bc/0x950 net/ipv4/udp.c:495 __udp4_lib_lookup+0x768/0xe20 net/ipv4/udp.c:723 __udp4_lib_lookup_skb+0x297/0x390 net/ipv4/udp.c:752 __udp4_lib_rcv+0x1312/0x2620 net/ipv4/udp.c:2752 ip_protocol_deliver_rcu+0x282/0x440 net/ipv4/ip_input.c:207 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6181 [inline] __netif_receive_skb net/core/dev.c:6294 [inline] process_backlog+0xaa4/0x1960 net/core/dev.c:6645 __napi_poll+0xae/0x340 net/core/dev.c:7709 napi_poll net/core/dev.c:7772 [inline] net_rx_action+0x5d7/0xf50 net/core/dev.c:7929 handle_softirqs+0x22b/0x870 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 </IRQ> <TASK> __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline] __dev_queue_xmit+0x1dd7/0x3710 net/core/dev.c:4890 neigh_output include/net/neighbour.h:556 [inline] ip_finish_output2+0xca9/0x1070 net/ipv4/ip_output.c:237 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip_output+0x29f/0x450 net/ipv4/ip_output.c:438 ip_send_skb+0x45/0xc0 net/ipv4/ip_output.c:1508 udp_send_skb+0xb04/0x1510 net/ipv4/udp.c:1195 udp_sendmsg+0x1a71/0x2350 net/ipv4/udp.c:1485 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] __sys_sendto+0x554/0x680 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x160/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x415a2d Code: b3 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6bc31e41e8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f6bc31e4cdc RCX: 0000000000415a2d RDX: 0000000000000001 RSI: 00007f6bc31e421f RDI: 0000000000000003 RBP: 00007f6bc31e4240 R08: 00007f6bc31e4220 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000212 R12: 00007f6bc31e46c0 R13: ffffffffffffffb8 R14: 0000000000000000 R15: 00007ffc9b0d70b0 </TASK> Fixes: 538950a1b752 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF") Reported-by: Eulgyu Kim <eulgyukim@snu.ac.kr> Reported-by: Taeyang Lee <0wn@theori.io> Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20260426012647.3233119-1-kuniyu@google.com
2026-05-08bpf: tcp: Fix type confusion in sol_tcp_sockopt().Kuniyuki Iwashima1-1/+1
sol_tcp_sockopt() only checks if sk->sk_protocol is IPPROTO_TCP, but RAW socket can bypass it: socket(AF_INET, SOCK_RAW, IPPROTO_TCP) Let's use sk_is_tcp(). Note that initially sol_tcp_sockopt() checked sk->sk_prot->setsockopt. Fixes: 2ab42c7b871f ("bpf: Check the protocol of a sock to agree the calls to bpf_setsockopt().") Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20260504210610.180150-7-kuniyu@google.com
2026-05-08bpf: tcp: Fix type confusion in bpf_skc_to_tcp6_sock().Kuniyuki Iwashima1-1/+1
bpf_skc_to_tcp6_sock() only checks if sk->sk_protocol is IPPROTO_TCP and sk->sk_family is AF_INET6, but RAW socket can bypass it: socket(AF_INET6, SOCK_RAW, IPPROTO_TCP) Let's check sk->sk_type too. Fixes: af7ec1383361 ("bpf: Add bpf_skc_to_tcp6_sock() helper") Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20260504210610.180150-6-kuniyu@google.com
2026-05-08bpf: tcp: Fix type confusion in bpf_skc_to_tcp_sock().Kuniyuki Iwashima1-1/+1
bpf_skc_to_tcp_sock() only checks if sk->sk_protocol is IPPROTO_TCP, but RAW socket can bypass it: socket(AF_INET, SOCK_RAW, IPPROTO_TCP) Let's use sk_is_tcp(). Fixes: 478cfbdf5f13 ("bpf: Add bpf_skc_to_{tcp, tcp_timewait, tcp_request}_sock() helpers") Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20260504210610.180150-5-kuniyu@google.com
2026-05-08bpf: tcp: Fix type confusion in bpf_tcp_sock().Kuniyuki Iwashima1-1/+1
bpf_tcp_sock() only checks if sk->sk_protocol is IPPROTO_TCP, but RAW socket can bypass it: socket(AF_INET, SOCK_RAW, IPPROTO_TCP) Calling bpf_setsockopt() in SOCKOPT prog triggers out-of-bounds access to another slab object. [0] Let's use sk_is_tcp(). [0]: BUG: KASAN: slab-out-of-bounds in sol_tcp_sockopt (net/core/filter.c:5519) Read of size 8 at addr ffff88801083d760 by task test_progs/1259 CPU: 1 UID: 0 PID: 1259 Comm: test_progs Tainted: G OE 7.0.0-11175-gb5c111f4967b #1 PREEMPT(full) Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120) print_report (mm/kasan/report.c:378 mm/kasan/report.c:482) kasan_report (mm/kasan/report.c:595) sol_tcp_sockopt (net/core/filter.c:5519) __bpf_getsockopt (net/core/filter.c:5633) bpf_sk_getsockopt (net/core/filter.c:5654) bpf_prog_629ba00a1601e9f2__setsockopt+0x86/0x22c __cgroup_bpf_run_filter_setsockopt (./include/linux/bpf.h:1402 ./include/linux/filter.h:722 ./include/linux/filter.h:729 kernel/bpf/cgroup.c:81 kernel/bpf/cgroup.c:2026) do_sock_setsockopt (net/socket.c:2363) __x64_sys_setsockopt (net/socket.c:2406) do_syscall_64 (arch/x86/entry/syscall_64.c:63) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) RIP: 0033:0x7f85f82fe7de Code: 55 48 63 c9 48 63 ff 45 89 c9 48 89 e5 48 83 ec 08 6a 2c e8 34 69 f7 ff c9 c3 66 90 f3 0f 1e fa 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 0a c3 66 0f 1f 84 00 00 00 00 00 48 8b 15 e1 RSP: 002b:00007ffe59dcecd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f85f82fe7de RDX: 000000000000001c RSI: 0000000000000006 RDI: 000000000000000d RBP: 00007ffe59dcef20 R08: 000000000000003c R09: 0000000000000000 R10: 00007ffe59dcef00 R11: 0000000000000202 R12: 00007ffe59dcf268 R13: 0000000000000003 R14: 00007f85f9da5000 R15: 000055b2f3201400 </TASK> The buggy address belongs to the object at ffff88801083d280 which belongs to the cache RAW of size 1792 The buggy address is located 1248 bytes inside of allocated 1792-byte region [ffff88801083d280, ffff88801083d980) Fixes: 655a51e536c0 ("bpf: Add struct bpf_tcp_sock and BPF_FUNC_tcp_sock") Reported-by: Damiano Melotti <melotti@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://patch.msgid.link/20260504210610.180150-2-kuniyu@google.com
2026-05-05net: prevent possible UAF in rtnl_prop_list_size()Eric Dumazet1-1/+1
I was mistaken by synchronize_rcu() [1] call in netdev_name_node_alt_destroy(), giving a false sense of RCU safety at delete times. We have to use list_del_rcu() to not confuse potential readers in rtnl_prop_list_size(). [1] This synchronize_rcu() call was later removed in commit 723de3ebef03 ("net: free altname using an RCU callback"). Fixes: 9f30831390ed ("net: add rcu safety to rtnl_prop_list_size()") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260502124102.499204-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05netpoll: pass buffer size to egress_dev() to avoid MAC truncationBreno Leitao1-10/+13
egress_dev() formats np->dev_mac via snprintf() but receives buf as a bare char *, so it cannot derive the buffer size from the pointer. The size argument was hardcoded to MAC_ADDR_STR_LEN (3 * ETH_ALEN - 1 = 17), which is silly wrong in two ways: 1) misleading kernel log output on the MAC-selected target path (np->dev_name[0] == '\0'); for example "aa:bb:cc:dd:ee:ff doesn't exist, aborting" was logged as "aa:bb:cc:dd:ee:f doesn't exist, aborting". 2) the second argument of snprintf is the size of the buffer, not the size of what you want to write. Add a bufsz parameter to egress_dev() and pass sizeof(buf) from each caller, matching the standard snprintf() idiom and removing the hardcoded size from the helper. Every caller already declares "char buf[MAC_ADDR_STR_LEN + 1]" so the formatted MAC continues to fit. Tested by booting with netconsole=6665@/aa:bb:cc:dd:ee:ff,6666@10.0.0.1/00:11:22:33:44:55 on a kernel without a matching device. Pre-fix dmesg shows "aa:bb:cc:dd:ee:f doesn't exist, aborting"; post-fix shows the full "aa:bb:cc:dd:ee:ff doesn't exist, aborting". Fixes: f8a10bed32f5 ("netconsole: allow selection of egress interface via MAC address") Cc: stable@vger.kernel.org Signed-off-by: Breno Leitao <leitao@debian.org> Link: https://patch.msgid.link/20260501-netpoll_snprintf_fix-v1-1-84b0566e6597@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-02net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in ↵Kai Zen1-0/+1
rtnl_fill_vfinfo rtnl_fill_vfinfo() declares struct ifla_vf_broadcast on the stack without initialisation: struct ifla_vf_broadcast vf_broadcast; The struct contains a single fixed 32-byte field: /* include/uapi/linux/if_link.h */ struct ifla_vf_broadcast { __u8 broadcast[32]; }; The function then copies dev->broadcast into it using dev->addr_len as the length: memcpy(vf_broadcast.broadcast, dev->broadcast, dev->addr_len); On Ethernet devices (the overwhelming majority of SR-IOV NICs) dev->addr_len is 6, so only the first 6 bytes of broadcast[] are written. The remaining 26 bytes retain whatever was previously on the kernel stack. The full struct is then handed to userspace via: nla_put(skb, IFLA_VF_BROADCAST, sizeof(vf_broadcast), &vf_broadcast) leaking up to 26 bytes of uninitialised kernel stack per VF per RTM_GETLINK request, repeatable. The other vf_* structs in the same function are explicitly zeroed for exactly this reason - see the memset() calls for ivi, vf_vlan_info, node_guid and port_guid a few lines above. vf_broadcast was simply missed when it was added. Reachability: any unprivileged local process can open AF_NETLINK / NETLINK_ROUTE without capabilities and send RTM_GETLINK with an IFLA_EXT_MASK attribute carrying RTEXT_FILTER_VF. The kernel walks each VF and emits IFLA_VF_BROADCAST, leaking 26 bytes of stack per VF per request. Stack residue at this call site can include return addresses and transient sensitive data; KASAN with stack instrumentation, or KMSAN, will flag the nla_put() when reproduced. Zero the on-stack struct before the partial memcpy, matching the existing pattern used for the other vf_* structs in the same function. Fixes: 75345f888f70 ("ipoib: show VF broadcast address") Cc: stable@vger.kernel.org Signed-off-by: Kai Zen <kai.aizen.dev@gmail.com> Link: https://patch.msgid.link/3c506e8f936e52b57620269b55c348af05d413a2.1777557228.git.kai.aizen.dev@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-30page_pool: fix memory-provider leak in page_pool_create_percpu() error pathHasan Basbunar1-5/+5
When page_pool_create_percpu() fails on page_pool_list(), it falls through to its err_uninit: label, which calls page_pool_uninit(). At that point page_pool_init() has already taken two references when the user requested PP_FLAG_ALLOW_UNREADABLE_NETMEM: pool->mp_ops->init(pool) static_branch_inc(&page_pool_mem_providers); Neither is undone by page_pool_uninit(); both are only undone by __page_pool_destroy() (success-side teardown). The error path therefore leaks the per-provider reference taken by mp_ops->init (io_zcrx_ifq->refs in the io_uring zcrx provider, the dmabuf binding refcount in the devmem provider) plus one increment of the page_pool_mem_providers static branch on every failure of xa_alloc_cyclic() inside page_pool_list(). The leaked io_zcrx_ifq->refs in turn pins everything io_zcrx_ifq_free() would release on cleanup: ifq->user (uid), ifq->mm_account (mmdrop), ifq->dev (device refcount), ifq->netdev_tracker (netdev refcount), and the rbuf region. The leaked static branch increment forces all subsequent page_pool_alloc_netmems() and page_pool_return_page() callers to take the slow mp_ops branch for the lifetime of the kernel. Reachable via the io_uring zcrx path: io_uring_register(IORING_REGISTER_ZCRX_IFQ) /* CAP_NET_ADMIN */ -> __io_uring_register -> io_register_zcrx -> zcrx_register_netdev -> netif_mp_open_rxq -> driver ndo_queue_mem_alloc -> page_pool_create_percpu -> page_pool_init succeeds (mp_ops->init runs, branch++) -> page_pool_list fails (xa_alloc_cyclic -ENOMEM) -> goto err_uninit <-- leak The same shape applies to the devmem dmabuf provider via mp_dmabuf_devmem_init()/mp_dmabuf_devmem_destroy(). Restore the cleanup symmetry by moving the mp_ops->destroy() and static_branch_dec() calls out of __page_pool_destroy() and into page_pool_uninit(), so page_pool_uninit() is again the strict inverse of page_pool_init(). page_pool_uninit() has only two callers (the err_uninit: path and __page_pool_destroy()), so this preserves the single-call invariant on the success path while fixing the err path. The error path of page_pool_init() itself still skips the mp_ops cleanup correctly: mp_ops->init is the last action that takes a reference before page_pool_init() returns 0, so when it returns an error neither the refcount nor the static branch has been touched. Triggering the bug requires xa_alloc_cyclic() to fail with -ENOMEM, which under normal GFP_KERNEL retry behaviour is rare. It is deterministic under CONFIG_FAULT_INJECTION with fail_page_alloc / xa fault injection, or under sustained memory pressure. The leak is silent: there is no warning, and the released kernel build continues running with a permanently-incremented static branch. Fixes: 0f9214046893 ("memory-provider: dmabuf devmem memory provider") Signed-off-by: Hasan Basbunar <basbunarhasan@gmail.com> Link: https://patch.msgid.link/20260428170739.34881-1-basbunarhasan@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-30net: add net_iov_init() and use it to initialize ->page_typeJakub Kicinski1-2/+1
Commit db359fccf212 ("mm: introduce a new page type for page pool in page type") added a page_type field to struct net_iov at the same offset as struct page::page_type, so that page_pool_set_pp_info() can call __SetPageNetpp() uniformly on both pages and net_iovs. The page-type API requires the field to hold the UINT_MAX "no type" sentinel before a type can be set; for real struct page that invariant is established by the page allocator on free. struct net_iov is not allocated through the page allocator, so the field is left as zero (io_uring zcrx, which uses __GFP_ZERO) or as slab garbage (devmem, which uses kvmalloc_objs() without zeroing). When the page pool then calls page_pool_set_pp_info() on a freshly-bound niov, __SetPageNetpp()'s VM_BUG_ON_PAGE(page->page_type != UINT_MAX) fires and the kernel BUGs. Triggered in selftests by io_uring zcrx setup through the fbnic queue restart path: kernel BUG at ./include/linux/page-flags.h:1062! RIP: 0010:page_pool_set_pp_info (./include/linux/page-flags.h:1062 net/core/page_pool.c:716) Call Trace: <TASK> net_mp_niov_set_page_pool (net/core/page_pool.c:1360) io_pp_zc_alloc_netmems (io_uring/zcrx.c:1089 io_uring/zcrx.c:1110) fbnic_fill_bdq (./include/net/page_pool/helpers.h:160 drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:906) __fbnic_nv_restart (drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2470 drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2874) fbnic_queue_start (drivers/net/ethernet/meta/fbnic/fbnic_txrx.c:2903) netdev_rx_queue_reconfig (net/core/netdev_rx_queue.c:137) __netif_mp_open_rxq (net/core/netdev_rx_queue.c:234) io_register_zcrx (io_uring/zcrx.c:818 io_uring/zcrx.c:903) __io_uring_register (io_uring/register.c:931) __do_sys_io_uring_register (io_uring/register.c:1029) do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) </TASK> The same path is reachable through devmem dmabuf binding via netdev_nl_bind_rx_doit() -> net_devmem_bind_dmabuf_to_queue(). Add a net_iov_init() helper that stamps ->owner, ->type and the ->page_type sentinel, and use it from both the devmem and io_uring zcrx niov init loops. Fixes: db359fccf212 ("mm: introduce a new page type for page pool in page type") Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Acked-by: Byungchul Park <byungchul@sk.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/20260428025320.853452-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28netpoll: fix IPv6 local-address corruptionBreno Leitao1-1/+18
netpoll_setup() decides whether to auto-populate the local source address by testing np->local_ip.ip, which only inspects the first 4 bytes of the union inet_addr storage. For an IPv6 netpoll whose caller-supplied local address has a zero high-32 bits (::1, ::<suffix>, IPv4-mapped ::ffff:a.b.c.d, etc.), this misdetects the address as unset (which they are not, but the first 4 bytes are empty), calls netpoll_take_ipv6() and overwrites it with whatever matching link-local/global address the device happens to expose first. Introduce a helper netpoll_local_ip_unset() that picks the correct family-aware test (ipv6_addr_any() for IPv6, !.ip for IPv4) and use it from netpoll_setup(). Reproducer is something like: echo "::2" > local_ip echo 1 > enabled cat local_ip # before this fix: 2001:db8::1 (caller-supplied ::2 was clobbered) # after this fix: ::2 Fixes: b7394d2429c1 ("netpoll: prepare for ipv6") Signed-off-by: Breno Leitao <leitao@debian.org> Link: https://patch.msgid.link/20260424-netpoll_fix-v1-1-3a55348c625f@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-28neigh: let neigh_xmit take skb ownershipFlorian Westphal1-5/+5
neigh_xmit always releases the skb, except when no neighbour table is found. But even the first added user of neigh_xmit (mpls) relied on neigh_xmit to release the skb (or queue it for tx). sashiko reported: If neigh_xmit() is called with an uninitialized neighbor table (for example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT and bypasses its internal out_kfree_skb error path. Because the return value of neigh_xmit() is ignored here, does this leak the SKB? Assume full ownership and remove the last code path that doesn't xmit or free skb. Fixes: 4fd3d7d9e868 ("neigh: Add helper function neigh_xmit") Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260424145843.74055-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-24bpf: Fix sk_local_storage diag dumping uninitialized special fieldsAmery Hung1-0/+1
Call check_and_init_map_value() after the copy_map_value() to zero out special field regions. diag_get() copies sk_local_storage map values into a netlink message using copy_map_value{_locked}(), which intentionally skip special fields. However, the destination buffer from nla_reserve_64bit() is not zeroed and the skipped regions contain uninitialized skb data can be sent to userspace. Fixes: 1ed4d92458a9 ("bpf: INET_DIAG support in bpf_sk_storage") Signed-off-by: Amery Hung <ameryhung@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20260423222356.155387-1-ameryhung@gmail.com
2026-04-24Merge tag 'net-deletions' of ↵Linus Torvalds1-7/+0
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking deletions from Jakub Kicinski: "Delete some obsolete networking code Old code like amateur radio and NFC have long been a burden to core networking developers. syzbot loves to find bugs in BKL-era code, and noobs try to fix them. If we want to have a fighting chance of surviving the LLM-pocalypse this code needs to find a dedicated owner or get deleted. We've talked about these deletions multiple times in the past and every time someone wanted the code to stay. It is never very clear to me how many of those people actually use the code vs are just nostalgic to see it go. Amateur radio did have occasional users (or so I think) but most users switched to user space implementations since its all super slow stuff. Nobody stepped up to maintain the kernel code. We were lucky enough to find someone who wants to help with NFC so we're giving that a chance. Let's try to put the rest of this code behind us" * tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: drivers: net: 8390: wd80x3: Remove this driver drivers: net: 8390: ultra: Remove this driver drivers: net: 8390: AX88190: Remove this driver drivers: net: fujitsu: fmvj18x: Remove this driver drivers: net: smsc: smc91c92: Remove this driver drivers: net: smsc: smc9194: Remove this driver drivers: net: amd: nmclan: Remove this driver drivers: net: amd: lance: Remove this driver drivers: net: 3com: 3c589: Remove this driver drivers: net: 3com: 3c574: Remove this driver drivers: net: 3com: 3c515: Remove this driver drivers: net: 3com: 3c509: Remove this driver net: packetengines: remove obsolete yellowfin driver and vendor dir net: packetengines: remove obsolete hamachi driver net: remove unused ATM protocols and legacy ATM device drivers net: remove ax25 and amateur radio (hamradio) subsystem net: remove ISDN subsystem and Bluetooth CMTP caif: remove CAIF NETWORK LAYER
2026-04-24bpf: Fix NULL pointer dereference in bpf_skb_fib_lookup()Weiming Shi1-0/+2
When tot_len is not provided by the user, bpf_skb_fib_lookup() resolves the FIB result's output device via dev_get_by_index_rcu() to check skb forwardability and fill in mtu_result. The returned pointer is dereferenced without a NULL check. If the device is concurrently unregistered, dev_get_by_index_rcu() returns NULL and is_skb_forwardable() crashes at dev->flags: KASAN: null-ptr-deref in range [0x00000000000000b0-0x00000000000000b7] Call Trace: is_skb_forwardable (include/linux/netdevice.h:4365) bpf_skb_fib_lookup (net/core/filter.c:6446) bpf_prog_test_run_skb (net/bpf/test_run.c) __sys_bpf (kernel/bpf/syscall.c) Add the missing NULL check, returning -ENODEV to be consistent with how bpf_ipv4_fib_lookup() and bpf_ipv6_fib_lookup() handle the same condition. Fixes: 4f74fede40df ("bpf: Add mtu checking to FIB forwarding helper") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Acked-by: Paul Chaignon <paul.chaignon@gmail.com> Link: https://patch.msgid.link/20260423183831.1325480-2-bestswngs@gmail.com
2026-04-24sockmap: Fix sk_psock_drop() race vs sock_map_{unhash,close,destroy}().Kuniyuki Iwashima1-14/+25
syzbot reported a splat in sock_map_destroy() [0], where psock was NULL even though sk->sk_prot still pointed to tcp_bpf_prots[][]. The stack trace shows how badly the path was excercised, see inet_release() calls tcp_close(), not sock_map_close() yet, but finally reaching sock_map_destroy(). The root cause is a lack of synchronisation. Even if sk_psock_get() fails to bump psock->refcnt, it does not guarantee that sk_psock_drop() has finished, and thus sk->sk_prot might not have been restored to the original one. Commit 4b4647add7d3 ("sock_map: avoid race between sock_map_close and sk_psock_put") attempted to address this, but it was insufficient for two reasons. It did not cover sock_map_unhash() and sock_map_destroy(), and it missed the corner case where sk_psock() is NULL. On non-x86 platforms, sk_psock_restore_proto(sk, psock) and rcu_assign_sk_user_data(sk, NULL) can be reordered because there is no address dependency between sk->sk_prot and sk->sk_user_data. sk_psock_get() returning NULL implies nothing about sk->sk_prot. Let's simply retry sk_psock_get() in the unlikely case. Note that we cannot avoid loop even if we added memory barrier in sk_psock_drop() and sock_map_psock_get_checked(). Also note that sock_map_destroy() cannot be called from softirq while sock_map_close() has also been running. It is because sock_map_destroy() requires SOCK_DEAD, so sock_map_destroy() cannot happen until sock_map_close() has finished the saved_close() (which is tcp_close()). [0]: WARNING: CPU: 1 PID: 8459 at net/core/sock_map.c:1667 sock_map_destroy+0x28b/0x2b0 net/core/sock_map.c:1667 Modules linked in: CPU: 1 UID: 0 PID: 8459 Comm: syz.0.1109 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:sock_map_destroy+0x28b/0x2b0 net/core/sock_map.c:1667 Code: 8b 36 49 83 c6 38 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 93 62 22 f9 4d 8b 3e e9 79 ff ff ff e8 a6 2b c3 f8 90 <0f> 0b 90 eb 9c e8 9b 2b c3 f8 4c 89 e7 be 03 00 00 00 e8 0e 4e bc RSP: 0018:ffffc9000d067be8 EFLAGS: 00010293 RAX: ffffffff88fb30aa RBX: ffff888024832000 RCX: ffff888024283b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed100862e946 R12: dffffc0000000000 R13: ffff888024832000 R14: ffffffff995b2208 R15: ffffffff88fb2e20 FS: 0000555579a7d500(0000) GS:ffff8881269c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000000048c0 CR3: 000000003713a000 CR4: 00000000003526f0 Call Trace: <TASK> inet_csk_destroy_sock+0x166/0x3a0 net/ipv4/inet_connection_sock.c:1294 __tcp_close+0xcc1/0xfd0 net/ipv4/tcp.c:3262 tcp_close+0x28/0x110 net/ipv4/tcp.c:3274 inet_release+0x144/0x190 net/ipv4/af_inet.c:435 __sock_release net/socket.c:649 [inline] sock_close+0xc0/0x240 net/socket.c:1439 __fput+0x45b/0xa80 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f265847ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd158dfbd8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000002ddb0 RCX: 00007f265847ebe9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f26586a7da0 R08: 0000000000000001 R09: 0000000e158dfecf R10: 0000001b30a20000 R11: 0000000000000246 R12: 00007f26586a5fac R13: 00007f26586a5fa0 R14: ffffffffffffffff R15: 00007ffd158dfcf0 </TASK> Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Fixes: b05545e15e1f ("bpf: sockmap, fix transition through disconnect without close") Fixes: d8616ee2affc ("bpf, sockmap: Fix sk->sk_forward_alloc warn_on in sk_stream_kill_queues") Reported-by: syzbot+b0842d38af58376d1fdc@syzkaller.appspotmail.com Closes: https://lore.kernel.org/bpf/69cec5ef.050a0220.2dbe29.0009.GAE@google.com/ Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260420194846.1089595-1-kuniyu@google.com
2026-04-24bpf: Fix NULL pointer dereference in bpf_sk_storage_clone and diag pathsWeiming Shi1-6/+7
bpf_selem_unlink_nofail() sets SDATA(selem)->smap to NULL before removing the selem from the storage hlist. A concurrent RCU reader in bpf_sk_storage_clone() can observe the selem still on the list with smap already NULL, causing a NULL pointer dereference. general protection fault, probably for non-canonical address 0xdffffc000000000a: KASAN: null-ptr-deref in range [0x0000000000000050-0x0000000000000057] RIP: 0010:bpf_sk_storage_clone+0x1cd/0xaa0 net/core/bpf_sk_storage.c:174 Call Trace: <IRQ> sk_clone+0xfed/0x1980 net/core/sock.c:2591 inet_csk_clone_lock+0x30/0x760 net/ipv4/inet_connection_sock.c:1222 tcp_create_openreq_child+0x35/0x2680 net/ipv4/tcp_minisocks.c:571 tcp_v4_syn_recv_sock+0x123/0xf90 net/ipv4/tcp_ipv4.c:1729 tcp_check_req+0x8e1/0x2580 include/net/tcp.h:855 tcp_v4_rcv+0x1845/0x3b80 net/ipv4/tcp_ipv4.c:2347 Add a NULL check for smap in bpf_sk_storage_clone(). bpf_sk_storage_diag_put_all() has the same issue. Add a NULL check and pass the validated smap directly to diag_get(), which is refactored to take smap as a parameter instead of reading it internally. bpf_sk_storage_diag_put() uses diag->maps[i] which is always valid under its refcount, so diag->maps[i] is passed directly to diag_get(). Fixes: 5d800f87d0a5 ("bpf: Support lockless unlink when freeing map or local storage") Reported-by: Xiang Mei <xmei5@asu.edu> Acked-by: Amery Hung <ameryhung@gmail.com> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20260422065411.1007737-2-bestswngs@gmail.com
2026-04-24Merge tag 'net-7.1-rc1' of ↵Linus Torvalds9-67/+801
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from Netfilter. Steady stream of fixes. Last two weeks feel comparable to the two weeks before the merge window. Lots of AI-aided bug discovery. A newer big source is Sashiko/Gemini (Roman Gushchin's system), which points out issues in existing code during patch review (maybe 25% of fixes here likely originating from Sashiko). Nice thing is these are often fixed by the respective maintainers, not drive-bys. Current release - new code bugs: - kconfig: MDIO_PIC64HPSC should depend on ARCH_MICROCHIP Previous releases - regressions: - add async ndo_set_rx_mode and switch drivers which we promised to be called under the per-netdev mutex to it - dsa: remove duplicate netdev_lock_ops() for conduit ethtool ops - hv_sock: report EOF instead of -EIO for FIN - vsock/virtio: fix MSG_PEEK calculation on bytes to copy Previous releases - always broken: - ipv6: fix possible UAF in icmpv6_rcv() - icmp: validate reply type before using icmp_pointers - af_unix: drop all SCM attributes for SOCKMAP - netfilter: fix a number of bugs in the osf (OS fingerprinting) - eth: intel: fix timestamp interrupt configuration for E825C Misc: - bunch of data-race annotations" * tag 'net-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (148 commits) rxrpc: Fix error handling in rxgk_extract_token() rxrpc: Fix re-decryption of RESPONSE packets rxrpc: Fix rxrpc_input_call_event() to only unshare DATA packets rxrpc: Fix missing validation of ticket length in non-XDR key preparsing rxgk: Fix potential integer overflow in length check rxrpc: Fix conn-level packet handling to unshare RESPONSE packets rxrpc: Fix potential UAF after skb_unshare() failure rxrpc: Fix rxkad crypto unalignment handling rxrpc: Fix memory leaks in rxkad_verify_response() net: rds: fix MR cleanup on copy error m68k: mvme147: Make me the maintainer net: txgbe: fix firmware version check selftests/bpf: check epoll readiness during reuseport migration tcp: call sk_data_ready() after listener migration vhost_net: fix sleeping with preempt-disabled in vhost_net_busy_poll() ipv6: Cap TLV scan in ip6_tnl_parse_tlv_enc_lim tipc: fix double-free in tipc_buf_append() llc: Return -EINPROGRESS from llc_ui_connect() ipv4: icmp: validate reply type before using icmp_pointers selftests/net: packetdrill: cover RFC 5961 5.2 challenge ACK on both edges ...
2026-04-23net: remove unused ATM protocols and legacy ATM device driversJakub Kicinski1-7/+0
Remove the ATM protocol modules and PCI/SBUS ATM device drivers that are no longer in active use. The ATM core protocol stack, PPPoATM, BR2684, and USB DSL modem drivers (drivers/usb/atm/) are retained in-tree to maintain PPP over ATM (PPPoA) and PPPoE-over-BR2684 support for DSL connections. The Solos ADSL2+ PCI driver is also retained. Removed ATM protocol modules: - net/atm/clip.c - Classical IP over ATM (RFC 2225) - net/atm/lec.c - LAN Emulation Client (LANE) - net/atm/mpc.c, mpoa_caches.c, mpoa_proc.c - Multi-Protocol Over ATM Removed PCI/SBUS ATM device drivers (drivers/atm/): - adummy, atmtcp - software/testing ATM devices - eni - Efficient Networks ENI155P (OC-3, ~1995) - fore200e - FORE Systems 200E PCI/SBUS (OC-3, ~1999) - he - ForeRunner HE (OC-3/OC-12, ~2000) - idt77105 - IDT 77105 25 Mbps ATM PHY - idt77252 - IDT 77252 NICStAR II (OC-3, ~2000) - iphase - Interphase ATM PCI (OC-3/DS3/E3) - lanai - Efficient Networks Speedstream 3010 - nicstar - IDT 77201 NICStAR (155/25 Mbps, ~1999) - suni - PMC S/UNI SONET PHY library Also clean up references in: - net/bridge/ - remove ATM LANE hook (br_fdb_test_addr_hook, br_fdb_test_addr) - net/core/dev.c - remove br_fdb_test_addr_hook export - defconfig files - remove ATM driver config options The removed code is moved to an out-of-tree module package (mod-orphan). Acked-by: Andy Shevchenko <andriy.shevchenko@intel.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260422041846.2035118-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-22bpf: Reject TCP_NODELAY in bpf-tcp-ccKaFai Wan1-0/+24
A BPF TCP congestion control program can call bpf_setsockopt() from its callbacks. In current kernels, if it calls bpf_setsockopt(TCP_NODELAY) from cwnd_event_tx_start(), the call can re-enter the TCP transmit path before the outer tcp_transmit_skb() has completed and advanced the send head. This can re-trigger CA_EVENT_TX_START and lead to unbounded recursion: tcp_transmit_skb() -> tcp_event_data_sent() -> tcp_ca_event(sk, CA_EVENT_TX_START) -> cwnd_event_tx_start() -> bpf_setsockopt(TCP_NODELAY) -> tcp_push_pending_frames() -> tcp_write_xmit() -> tcp_transmit_skb() This leads to unbounded recursion and can overflow the kernel stack. Reject TCP_NODELAY with -EOPNOTSUPP for bpf-tcp-cc by introducing a dedicated setsockopt proto for BPF_PROG_TYPE_STRUCT_OPS TCP congestion control programs. To keep it simple, all tcp-cc ops is rejected for TCP_NODELAY. Fixes: 7e41df5dbba2 ("bpf: Add a few optnames to bpf_setsockopt") Suggested-by: Martin KaFai Lau <martin.lau@linux.dev> Signed-off-by: KaFai Wan <kafai.wan@linux.dev> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260421155804.135786-3-kafai.wan@linux.dev
2026-04-22bpf: Reject TCP_NODELAY in TCP header option callbacksKaFai Wan1-0/+6
A BPF_SOCK_OPS program can enable BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG and then call bpf_setsockopt(TCP_NODELAY) from BPF_SOCK_OPS_HDR_OPT_LEN_CB or BPF_SOCK_OPS_WRITE_HDR_OPT_CB. In these callbacks, bpf_setsockopt(TCP_NODELAY) can reach __tcp_sock_set_nodelay(), which can call tcp_push_pending_frames(). >From BPF_SOCK_OPS_HDR_OPT_LEN_CB, tcp_push_pending_frames() can call tcp_current_mss(), which calls tcp_established_options() and re-enters bpf_skops_hdr_opt_len(). BPF_SOCK_OPS_HDR_OPT_LEN_CB -> bpf_setsockopt(TCP_NODELAY) -> tcp_push_pending_frames() -> tcp_current_mss() -> tcp_established_options() -> bpf_skops_hdr_opt_len() -> BPF_SOCK_OPS_HDR_OPT_LEN_CB >From BPF_SOCK_OPS_WRITE_HDR_OPT_CB, tcp_push_pending_frames() can call tcp_write_xmit(), which calls tcp_transmit_skb(). That path recomputes header option length through tcp_established_options() and bpf_skops_hdr_opt_len() before re-entering bpf_skops_write_hdr_opt(). BPF_SOCK_OPS_WRITE_HDR_OPT_CB -> bpf_setsockopt(TCP_NODELAY) -> tcp_push_pending_frames() -> tcp_write_xmit() -> tcp_transmit_skb() -> tcp_established_options() -> bpf_skops_hdr_opt_len() -> bpf_skops_write_hdr_opt() -> BPF_SOCK_OPS_WRITE_HDR_OPT_CB This leads to unbounded recursion and can overflow the kernel stack. Reject TCP_NODELAY with -EOPNOTSUPP in bpf_sock_ops_setsockopt() when bpf_setsockopt() is called from BPF_SOCK_OPS_HDR_OPT_LEN_CB or BPF_SOCK_OPS_WRITE_HDR_OPT_CB. Fixes: 7e41df5dbba2 ("bpf: Add a few optnames to bpf_setsockopt") Closes: https://lore.kernel.org/bpf/d1d523c9-6901-4454-a183-94462b8f3e4e@std.uestc.edu.cn/ Reported-by: Quan Sun <2022090917019@std.uestc.edu.cn> Reported-by: Yinhao Hu <dddddd@hust.edu.cn> Reported-by: Kaiyan Mei <M202472210@hust.edu.cn> Signed-off-by: KaFai Wan <kafai.wan@linux.dev> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260421155804.135786-2-kafai.wan@linux.dev
2026-04-21net: warn ops-locked drivers still using ndo_set_rx_modeStanislav Fomichev2-1/+7
Now that all in-tree ops-locked drivers have been converted to ndo_set_rx_mode_async, add a warning in register_netdevice to catch any remaining or newly added drivers that use ndo_set_rx_mode with ops locking. This ensures future driver authors are guided toward the async path. Also route ops-locked devices through netdev_rx_mode_work even if they lack rx_mode NDOs, to ensure netdev_ops_assert_locked() does not fire on the legacy path where only RTNL is held. Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20260416185712.2155425-14-sdf@fomichev.me Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-21net: move promiscuity handling into netdev_rx_mode_workStanislav Fomichev2-34/+64
Move unicast promiscuity tracking into netdev_rx_mode_work so it runs under netdev_ops_lock instead of under the addr_lock spinlock. This is required because __dev_set_promiscuity calls dev_change_rx_flags and __dev_notify_flags, both of which may need to sleep. Change ASSERT_RTNL() to netdev_ops_assert_locked() in __dev_set_promiscuity, netif_set_allmulti and __dev_change_flags since these are now called from the work queue under the ops lock. Link: https://lore.kernel.org/netdev/20260214033859.43857-1-jiayuan.chen@linux.dev/ Fixes: 78cd408356fe ("net: add missing instance lock to dev_set_promiscuity") Reported-by: syzbot+2b3391f44313b3983e91@syzkaller.appspotmail.com Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20260416185712.2155425-5-sdf@fomichev.me Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-21net: cache snapshot entries for ndo_set_rx_mode_asyncStanislav Fomichev3-37/+92
Add a per-device netdev_hw_addr_list cache (rx_mode_addr_cache) that allows __hw_addr_list_snapshot() and __hw_addr_list_reconcile() to reuse previously allocated entries instead of hitting GFP_ATOMIC on every snapshot cycle. snapshot pops entries from the cache when available, falling back to __hw_addr_create(). reconcile splices both snapshot lists back into the cache via __hw_addr_splice(). The cache is flushed in free_netdev(). Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20260416185712.2155425-4-sdf@fomichev.me Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-21net: introduce ndo_set_rx_mode_async and netdev_rx_mode_workStanislav Fomichev6-43/+222
Add ndo_set_rx_mode_async callback that drivers can implement instead of the legacy ndo_set_rx_mode. The legacy callback runs under the netif_addr_lock spinlock with BHs disabled, preventing drivers from sleeping. The async variant runs from a work queue with rtnl_lock and netdev_lock_ops held, in fully sleepable context. When __dev_set_rx_mode() sees ndo_set_rx_mode_async, it schedules netdev_rx_mode_work instead of calling the driver inline. The work function takes two snapshots of each address list (uc/mc) under the addr_lock, then drops the lock and calls the driver with the work copies. After the driver returns, it reconciles the snapshots back to the real lists under the lock. Add netif_rx_mode_sync() to opportunistically execute the pending workqueue update inline, so that rx mode changes are committed before returning to userspace: - dev_change_flags (SIOCSIFFLAGS / RTM_NEWLINK) - dev_set_promiscuity - dev_set_allmulti - dev_ifsioc SIOCADDMULTI / SIOCDELMULTI - do_setlink (RTM_SETLINK) Note that some deep hierarchies still do skip the lower updates via: - dev_uc_sync - dev_mc_sync If we do end up hitting user-visible issues, we can add more calls to netif_rx_mode_sync in specific places. But hopefully we should not, the actual user-visible lists are still synced, it's that just HW state that might be lagging. Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20260416185712.2155425-3-sdf@fomichev.me Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-21net: add address list snapshot and reconciliation infrastructureStanislav Fomichev3-3/+470
Introduce __hw_addr_list_snapshot() and __hw_addr_list_reconcile() for use by the upcoming ndo_set_rx_mode_async callback. The async rx_mode path needs to snapshot the device's unicast and multicast address lists under the addr_lock, hand those snapshots to the driver (which may sleep), and then propagate any sync_cnt changes back to the real lists. Two identical snapshots are taken: a work copy for the driver to pass to __hw_addr_sync_dev() and a reference copy to compute deltas against. __hw_addr_list_reconcile() walks the reference snapshot comparing each entry against the work snapshot to determine what the driver synced or unsynced. It then applies those deltas to the real list, handling concurrent modifications: - If the real entry was concurrently removed but the driver synced it to hardware (delta > 0), re-insert a stale entry so the next work run properly unsyncs it from hardware. - If the entry still exists, apply the delta normally. An entry whose refcount drops to zero is removed. # dev_addr_test_snapshot_benchmark: 1024 addrs x 1000 snapshots: 89872802 ns total, 89872 ns/iter # dev_addr_test_snapshot_benchmark.speed: slow Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20260416185712.2155425-2-sdf@fomichev.me Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-20flow_dissector: do not dissect PPPoE PFC framesQingfang Deng1-8/+5
RFC 2516 Section 7 states that Protocol Field Compression (PFC) is NOT RECOMMENDED for PPPoE. In practice, pppd does not support negotiating PFC for PPPoE sessions, and the flow dissector driver has assumed an uncompressed frame until the blamed commit. During the review process of that commit [1], support for PFC is suggested. However, having a compressed (1-byte) protocol field means the subsequent PPP payload is shifted by one byte, causing 4-byte misalignment for the network header and an unaligned access exception on some architectures. The exception can be reproduced by sending a PPPoE PFC frame to an ethernet interface of a MIPS board, with RPS enabled, even if no PPPoE session is active on that interface: $ 0 : 00000000 80c40000 00000000 85144817 $ 4 : 00000008 00000100 80a75758 81dc9bb8 $ 8 : 00000010 8087ae2c 0000003d 00000000 $12 : 000000e0 00000039 00000000 00000000 $16 : 85043240 80a75758 81dc9bb8 00006488 $20 : 0000002f 00000007 85144810 80a70000 $24 : 81d1bda0 00000000 $28 : 81dc8000 81dc9aa8 00000000 805ead08 Hi : 00009d51 Lo : 2163358a epc : 805e91f0 __skb_flow_dissect+0x1b0/0x1b50 ra : 805ead08 __skb_get_hash_net+0x74/0x12c Status: 11000403 KERNEL EXL IE Cause : 40800010 (ExcCode 04) BadVA : 85144817 PrId : 0001992f (MIPS 1004Kc) Call Trace: [<805e91f0>] __skb_flow_dissect+0x1b0/0x1b50 [<805ead08>] __skb_get_hash_net+0x74/0x12c [<805ef330>] get_rps_cpu+0x1b8/0x3fc [<805fca70>] netif_receive_skb_list_internal+0x324/0x364 [<805fd120>] napi_complete_done+0x68/0x2a4 [<8058de5c>] mtk_napi_rx+0x228/0xfec [<805fd398>] __napi_poll+0x3c/0x1c4 [<805fd754>] napi_threaded_poll_loop+0x234/0x29c [<805fd848>] napi_threaded_poll+0x8c/0xb0 [<80053544>] kthread+0x104/0x12c [<80002bd8>] ret_from_kernel_thread+0x14/0x1c Code: 02d51821 1060045b 00000000 <8c640000> 3084000f 2c820005 144001a2 00042080 8e220000 To reduce the attack surface and maintain performance, do not process PPPoE PFC frames. [1] https://lore.kernel.org/r/20220630231016.GA392@debian.home Fixes: 46126db9c861 ("flow_dissector: Add PPPoE dissectors") Signed-off-by: Qingfang Deng <qingfang.deng@linux.dev> Link: https://patch.msgid.link/20260415022456.141758-1-qingfang.deng@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>