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4 dayssctp: validate chunk length in the inqueue parserCharles Vosburgh1-2/+4
SCTP chunks always include a four-byte generic header, but sctp_inq_pop() currently accepts shorter declared lengths. A zero-length chunk leaves chunk_end at the current header. When ASCONF is covered by the association's SCTP-AUTH policy, sctp_assoc_bh_rcv() can continue before the state machine performs its normal chunk-length check. sctp_inq_pop() then returns the same malformed chunk repeatedly and the receive softirq can lock up. A remote SCTP peer can trigger this after establishing an association on a kernel built with CONFIG_IP_SCTP and configured with net.sctp.addip_enable=1 and net.sctp.auth_enable=1. The reproducer did not require application credentials, a shared SCTP AUTH key, or net.sctp.addip_noauth_enable=1. On commit f967455fb2a5 ("seg6: reset IP6CB after IPv6 decapsulation"), one zero-length ASCONF caused repeated watchdog soft-lockup reports in a two-vCPU KVM guest. All 3 pre-trigger health probes succeeded, while 36 of 37 post-trigger probes failed. With this change, all 37 post-trigger probes succeeded and no equivalent soft-lockup signature appeared. Reject chunks shorter than the generic SCTP header at the shared inqueue parser boundary. Mark the packet for discard before either caller can continue processing it, while preserving the four-byte generic minimum. Declared-length 1 through 4 controls and kernel-generated ASCONF traffic remained healthy. The patched sctp_hello selftest passed for IPv4 and IPv6. The complete private reproducer and validation evidence are available directly to maintainers on request. Fixes: bbd0d59809f9 ("[SCTP]: Implement the receive and verification of AUTH chunk") Cc: stable@vger.kernel.org Signed-off-by: Charles Vosburgh <theminershive@gmail.com> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/20260827-sctp-zero-chunk-inqueue-v2-1-2e7669c6a6cb@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
4 daysraw: annotate disconnect-side IPv4 match writersXuanqiang Luo1-2/+2
raw_v4_match() reads inet_daddr, inet_rcv_saddr and sk_bound_dev_if locklessly under RCU. Bind and connect writers are annotated, but __udp_disconnect() still clears the same fields using plain stores. Commit 18f116931f52e ("raw: annotate lockless match fields in raw_v4_match()") added the lockless readers and annotated the raw bind and datagram connect writers. Its v4 revision intentionally left the shared disconnect-side IPv4 writers for follow-up cleanup. Complete that follow-up by using WRITE_ONCE() for the disconnect-side stores, including the inet_rcv_saddr reset in inet_reset_saddr(), to pair with the lockless raw socket matcher. Fixes: 0daf07e52709 ("raw: convert raw sockets to RCU") Link: https://lore.kernel.org/netdev/20260716142958.3064224-1-runyu.xiao@seu.edu.cn/ Suggested-by: Runyu Xiao <runyu.xiao@seu.edu.cn> Signed-off-by: Jackie Liu <liuyun01@kylinos.cn> Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260828012918.1461-1-xuanqiang.luo@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
4 dayssctp: fix soft lockup from unpadded ASCONF-ACK parameter iterationHenry Martin1-8/+6
sctp_verify_asconf() walks ASCONF-ACK parameters with sctp_walk_params(), which advances by SCTP_PAD4(length), while the consumer sctp_get_asconf_response() iterates the same parameters advancing by the raw length, without padding. A single odd-length parameter desynchronises the two walks and makes the consumer interpret attacker-controlled bytes at a misaligned offset. When those bytes yield a length of zero, the while loop over asconf_ack_len makes no progress, spinning forever in softirq context, and the watchdog reports a soft lockup. All reads stay within the received skb, so the lockup is a pure remote denial of service. A remote peer can trigger it with a crafted ASCONF-ACK on an ADD-IP enabled association with an outstanding ASCONF (RFC 5061 section 4.1.2 requires the chunk to be authenticated, but the predefined empty key id 0 allows the peer to compute the same association HMAC from publicly exchanged parameters, so the gate does not help). The SCTP_PARAM_ERR_CAUSE case of sctp_verify_asconf() also performs no length check, letting a parameter without a complete error header reach the consumer, which reads errhdr.cause past the end of the parameter, an out-of-bounds read. Reject SCTP_PARAM_ERR_CAUSE parameters shorter than sizeof(struct sctp_addip_param) + sizeof(struct sctp_errhdr) at the verifier, and advance the consumer iterator with the same padding rule as the verifier to keep the two walks in lockstep. The verifier change guarantees a complete error header in every ERR_CAUSE parameter the consumer can see, so the consumer's asconf_ack_len check is dropped and it returns err_param->cause directly. The consumer padding fix is still required because odd lengths remain valid for SCTP_PARAM_ERR_CAUSE per RFC 5061. The issue was found by ZeroHive, a vulnerability hunting agent at Tencent Yunding Lab. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/20260828042431.3873725-1-bsdhenrymartin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 dayssctp: fix a TOCTOU race in SCTP_CMD_TIMER_STARTXin Long1-10/+1
The SCTP_CMD_TIMER_START handler checks timer_pending() before calling timer_reduce(). The timer can expire and detach between these operations, causing timer_reduce() to rearm the timer without taking the association reference required for the newly armed timer. The timer callback later unconditionally drops its association reference, which can leave the association reference count unbalanced and result in use-after-free during association teardown. Use the return value of timer_reduce() to determine whether the timer was actually armed. Take the association reference only when timer_reduce() successfully starts a new timer, closing the race between checking the timer state and rearming it. This issue was reported by Nico Yip (@_cyeaa_) working with TrendAI Zero Day Initiative. Fixes: 20a785aa52c8 ("sctp: Don't add the shutdown timer if its already been added") Reported-by: Zero Day Initiative <zdi-disclosures@trendmicro.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/9d8f1b5c50329d5ea7c642128d35681abaa9ed20.1787773744.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daystcp: fix use-after-free in do_tcp_getsockopt(TCP_CC_INFO)Cen Zhang (Microsoft Security FORGE Labs)2-2/+4
do_tcp_getsockopt() reads icsk->icsk_ca_ops and dereferences the get_info function pointer without rcu_read_lock(). With BPF struct_ops congestion control, ca_ops can point to dynamically allocated memory that is freed concurrently, resulting in a use-after-free when the kernel dereferences or calls through the stale pointer. BUG: KASAN: slab-use-after-free in do_tcp_getsockopt+0x2037/0x23e0 Read of size 8 at addr ffff888013701258 by task exploit/149 do_tcp_getsockopt+0x2037/0x23e0 (net/ipv4/tcp.c:4564) tcp_getsockopt+0x91/0xf0 __sys_getsockopt+0xf7/0x170 Fix this by wrapping the ca_ops load and get_info call within rcu_read_lock()/rcu_read_unlock(), and using READ_ONCE() to load the icsk_ca_ops pointer. Fixes: 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf") Suggested-by: Eric Dumazet <edumazet@google.com> Cc: AutonomousCodeSecurity@microsoft.com Cc: stable@vger.kernel.org Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Cen Zhang (Microsoft Security FORGE Labs) <blbllhy@gmail.com> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/65fd3816ed5d541d9edd4bf4fcf97104a2cf907a.1787870710.git.blbllhy@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daystcp: fix use-after-free in do_tcp_getsockopt(TCP_CONGESTION)Cen Zhang (Microsoft Security FORGE Labs)5-8/+16
do_tcp_getsockopt() reads icsk->icsk_ca_ops->name without holding rcu_read_lock(). Since commit 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf"), icsk_ca_ops can point to dynamically allocated BPF struct_ops memory that may be freed concurrently via setsockopt(TCP_CONGESTION), leading to a use-after-free. BUG: KASAN: slab-use-after-free in _copy_to_user+0x37/0x60 Read of size 16 at addr ffff888013505260 by task exploit/149 _copy_to_user+0x37/0x60 do_tcp_getsockopt+0x158a/0x2460 (net/ipv4/tcp.c:4585) tcp_getsockopt+0x91/0xf0 __sys_getsockopt+0xf7/0x170 Fix this by holding rcu_read_lock() around the ca_ops->name access, using READ_ONCE() to load icsk_ca_ops, and copying the name to a stack buffer before releasing the lock. Also annotate the relevant icsk_ca_ops stores with WRITE_ONCE() to fix the accompanying KCSAN data-race issue. Fixes: 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf") Suggested-by: Eric Dumazet <edumazet@google.com> Reported-by: Xiang Mei (Microsoft) <xmei5@asu.edu> Link: https://lore.kernel.org/all/20260821182449.79785-2-blbllhy@gmail.com/ Cc: AutonomousCodeSecurity@microsoft.com Cc: stable@vger.kernel.org Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Cen Zhang (Microsoft Security FORGE Labs) <blbllhy@gmail.com> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Breno Leitao <leitao@debian.org> Link: https://patch.msgid.link/d3f97f1acbf0010898148be6e6406e4b8b4a5c84.1787870710.git.blbllhy@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daysnet/sched: act_api: fix skb sizing and action leak on reoffload deleteVictor Nogueira1-6/+11
tcf_reoffload_del_notify_msg() sizes the RTM_DELACTION skb with tcf_action_fill_size(action) alone. Unlike every other notification path it never wraps that in tcf_action_full_attrs_size(), so the nlmsg_put() header, struct tcamsg and the TCA_ACT_TAB nest that tca_get_fill() emits - 24 bytes on x86_64 - are not budgeted. As long as the single action stays well under NLMSG_GOODSIZE the floor in alloc_skb() hides this, but once its fill size crosses NLMSG_GOODSIZE the allocation is exactly 24 bytes short and tca_get_fill() runs out of tailroom. That is now easy to reach for an offloadable act_pedit with a large tcfp_nkeys, which commit 8e2efb3f45a5 ("net/sched: add get_fill_size callbacks for actions missing them") started accounting for properly. When that happens tcf_reoffload_del_notify() returns early, before tcf_idr_release_unsafe(), and tcf_action_reoffload_cb() discards the return value: if (tc_act_skip_sw(p->tcfa_flags) && !tc_act_in_hw(p)) tcf_reoffload_del_notify(net, p); The action has just lost its last hardware instance and is skip_sw, so it is left installed while processing no packets, and with no notification to tell userspace about it. An -ENOBUFS from alloc_skb() gets the same treatment. Fix this by budgeting the message header the way the add and delete paths do, and release the action even when the notification cannot be built - dropping the notification is strictly better than leaking a dead action, and there is no caller left to report the error to. Fixes: 13926d19a11e ("flow_offload: add reoffload process to update hw_count") Reported-by: Sashiko <sashiko-bot@kernel.org> Closes: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260810164357.1653956-1-victor%40mojatatu.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Reviewed-by: Pedro Tammela <pctammela@mojatatu.com> Link: https://patch.msgid.link/20260824153903.4143642-4-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daysnet/sched: act_api: size the RTM_GETACTION reply from the actionsVictor Nogueira1-3/+4
tca_action_gd() already walks every requested action and accumulates attr_size += tcf_action_fill_size(act), then wraps the result in tcf_action_full_attrs_size(). For RTM_DELACTION that value is handed to tcf_del_notify_msg(), which allocates max(attr_size, NLMSG_GOODSIZE). For RTM_GETACTION it is silently discarded and tcf_get_notify() allocates a fixed NLMSG_GOODSIZE skb instead. Any action whose dump exceeds that fixed budget therefore cannot be read back. For example, act_pedit overruns the budget with 32 actions of four munge keys each, act_police with 32 policers once the optional rate/peakrate/result/avrate attributes are present Fix this by passing attr_size through and allocate the reply the way the add and delete paths do. Note on exposure: RTM_GETACTION is the only one of the three action commands that is not capability checked - tc_ctl_action() requires CAP_NET_ADMIN for RTM_NEWACTION and RTM_DELACTION only - so this turns a fixed NLMSG_GOODSIZE reply into a user sized allocation on an unprivileged path. It is bounded by TCA_ACT_MAX_PRIO actions per request, and tca_action_gd() does not reject duplicate indices, so a single large action can be requested 32 times; an act_bpf program near BPF_MAXINSNS is about 32KB of dump, or roughly 1MB for one request. Creating such an action still requires CAP_NET_ADMIN, and the add and delete paths have sized their skbs this way since the Fixes commit. Should this ever need bounding, GFP_KERNEL_ACCOUNT would charge the reply to the caller's memcg. Fixes: 4e76e75d6aba ("net sched actions: calculate add/delete event message size") Reported-by: Sashiko <sashiko-bot@kernel.org> Closes: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260810164357.1653956-1-victor%40mojatatu.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260824153903.4143642-3-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daysnet/sched: act_api: budget all shared attributes in notify skbsVictor Nogueira1-2/+11
tcf_action_shared_attrs_size() is supposed to return an upper bound on the netlink attributes every action dump emits outside of TCA_ACT_OPTIONS, so that tcf_add_notify_msg(), tcf_del_notify_msg() and friends can allocate an skb large enough for the reply. It has fallen behind the dump path and is now an underestimate for every single action. Attributes, such as, TCA_ACT_IN_HW_COUNT and TCA_STATS_BASIC_HW are emitted unconditionally and never accounted for. TCA_STATS_PKT64, TCA_ACT_USED_HW_STATS, TCA_STATS_RATE_EST, TCA_STATS_RATE_EST64 require specific conditions, but are also not accounted for. Fix the issue by budgeting all of them so that we have a legitimate upper bound. Even tough for of them require specific conditions, they are cheap so, to avoid overcomplicating, we opted to account for them unconditionally as well to account for a real worst case scenario. Fixes: 4e76e75d6aba ("net sched actions: calculate add/delete event message size") Reported-by: Sashiko <sashiko-bot@kernel.org> Closes: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260810164357.1653956-1-victor%40mojatatu.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260824153903.4143642-2-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daysnet: iptunnel: fix stale transport header during tunnel decapsulationDong Chenchen1-0/+2
Syzbot reported a crash in qdisc_pkt_len_segs_init() caused by a stale transport_header offset after tunnel decapsulation. BUG: unable to handle page fault for address: ffffed102091a42e Oops: Oops: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 340 Comm: qdisc_uaf_repro Not tainted 7.2.0-rc4-00061-g248951ddc14d #256 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:__asan_load2 <IRQ> qdisc_pkt_len_segs_init (net/core/dev.c:4145) __dev_queue_xmit (net/core/dev.c:4787) br_dev_queue_push_xmit (net/bridge/br_forward.c:53) br_handle_frame_finish (net/bridge/br_input.c:229) br_handle_frame (net/bridge/br_input.c:315) __netif_receive_skb_core.constprop.0 (net/core/dev.c:6099) __netif_receive_skb_list_core (net/core/dev.c:6287) netif_receive_skb_list_internal (net/core/dev.c:6445) napi_complete_done (net/core/dev.c:6813) gro_cell_poll (net/core/gro_cells.c:74) __napi_poll (net/core/dev.c:7735) net_rx_action (net/core/dev.c:7798 net/core/dev.c:7955) handle_softirqs (kernel/softirq.c:622) do_softirq (kernel/softirq.c:523 kernel/softirq.c:510 ) __local_bh_enable_ip (kernel/softirq.c:450) tun_get_user (drivers/net/tun.c:1986 (discriminator 1)) tun_chr_write_iter (drivers/net/tun.c:2032) The issue is completely latent until qdisc read transport header in commit 7fb4c1967011 ("net: pull headers in qdisc_pkt_len_segs_init()"). The crash requires four conditions to line up: 1. The incoming packet is encapsulated and carries GSO metadata. The outer transport header offset is stored in skb->transport_header while the packet is still in the outer tunnel context. 2. The tunnel receiver strips the outer headers. skb->data is advanced to the inner frame, but skb->transport_header is left pointing to the now-removed outer L4 header, so it becomes a negative offset relative to the new data. 3. The inner frame is not delivered to the local IP stack. Instead, it is forwarded at L2 by a bridge or HSR, so ip_rcv_core() never runs and the transport header is not reset to the inner L4 offset. 4. The forwarding path calls __dev_queue_xmit(), which enters qdisc_pkt_len_segs_init(). That function computes the GSO header length from skb_transport_offset(skb). Because the offset is negative, the unsigned cast overflows and pskb_may_pull(skb, hdr_len + sizeof(struct tcphdr)) reads past the end of the skb, triggering a KASAN fault or page fault. The issue specifically requires GSO packets (shinfo->gso_size != 0), which are processed/aggregated through gro_cells. Fix this by clearing transport_header to the ~0U sentinel in gro_cell for all tunnnel driver. GTP does not support GRO/GSO, drop the evil GSO packets in GTP directly. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+83181a31faf9455499c5@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69de2bee.a00a0220.475f0.0041.GAE@google.com/T/ Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260825123909.1463121-1-dongchenchen2@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daystcp: use GFP_ATOMIC in tcp_send_active_reset()Eric Dumazet5-16/+13
tcp_send_active_reset() can be called from contexts where gfp_any() (in tcp_disconnect()) or sk->sk_allocation (in __tcp_close() and mptcp_do_fastclose()) evaluates to GFP_KERNEL, which includes __GFP_FS and __GFP_DIRECT_RECLAIM. Allocating with GFP_KERNEL while holding the socket lock (sk_lock) creates a lockdep dependency: sk_lock -> fs_reclaim This causes false-positive lockdep circular locking warnings with storage subsystems (such as nvme-tcp) that acquire socket locks in block I/O paths and invoke tcp_disconnect() or close sockets upon teardown: set->srcu -> sk_lock -> fs_reclaim -> elevator_lock -> set->srcu Active resets are small RST packet headers that should never enter direct reclaim or block while holding socket locks. Use sk_gfp_mask(sk, GFP_ATOMIC | __GFP_NOWARN) inside tcp_send_active_reset() and remove its priority argument. This preserves __GFP_MEMALLOC access for SOCK_MEMALLOC sockets, suppresses allocation failure warnings, and aligns with other control packet allocations (e.g. tcp_send_fin(), __tcp_send_ack(), tcp_xmit_probe_skb()). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20260827095936.551524-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daystipc: protect node reset trace dump with node lockChengfeng Ye1-0/+2
The tipc_node_reset_links trace event asks tipc_node_dump() to walk the node's link entries. Unlike the other node events that request link data, this event runs without the node lock. This permits bearer teardown to free a link while the trace callback is dumping it: CPU 0 CPU 1 trace_tipc_node_reset_links() tipc_node_dump() l = n->links[0].link tipc_node_write_lock() kfree(l) n->links[0].link = NULL tipc_node_write_unlock() tipc_link_dump(l) tipc_link_dump() then dereferences the stale pointer. KASAN reported: BUG: KASAN: slab-use-after-free in tipc_link_dump Read of size 4 by task poc/115 Call Trace: tipc_link_dump+0x10cb/0x16b0 tipc_node_dump+0x4bb/0x740 trace_event_raw_event_tipc_node_class+0x258/0x360 tipc_node_reset_links+0x14d/0x1a0 tipc_rcv+0x13f5/0x3030 tipc_udp_recv+0x4e3/0x670 Allocated by task 0: tipc_link_create+0x1e1/0x1020 tipc_node_check_dest+0x7d2/0x11a0 tipc_disc_rcv+0xdbf/0x1430 Freed by task 89: kfree+0x131/0x3c0 tipc_node_link_down+0x267/0x4b0 tipc_node_delete_links+0xec/0x160 bearer_disable+0x107/0x260 Take the node write lock around the trace event. This serializes the dump against tipc_node_link_down(delete=true), which frees the link under the same write lock. Fixes: eb18a510b5cd ("tipc: add trace_events for tipc node") Cc: stable@vger.kernel.org Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Link: https://patch.msgid.link/20260825190141.242219-1-nicoyip.dev@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
6 daysipv4: avoid divide by zero in fib_rebalanceZihan Xi1-1/+1
fib_rebalance() computes the total eligible nexthop weight in one pass and programs upper bounds in a second pass. A concurrent change to ignore_routes_with_linkdown can make the first pass return zero while the second pass sees an eligible nexthop, resulting in division by zero. If the first pass reports a zero total, set each nexthop upper bound to -1 and skip the division. This matches the IPv6 fix in commit d2c26c2911dd ("ipv6: avoid divide by zero in rt6_multipath_rebalance") and preserves the lock-free rebalance path. Fixes: 0e884c78ee19 ("ipv4: L3 hash-based multipath") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Zihan Xi <zihanx@nebusec.ai> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260827182514.4667-2-zihanx@nebusec.ai Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daysMerge tag 'net-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds135-862/+1662
Pull networking fixes from Jakub Kicinski: "Including fixes from Bluetooth, IPSec and Netfilter. Current release - fix to a fix: - netfilter: ipset: remove need to allocate memory on delete operations Current release - regressions: - macb: drop CONFIG_OF #if block, fix build Previous releases - always broken: - stream of fixes for SCTP continues - inet: frags: strip GSO state from fragments before reassembly - virtio-net: ensure that TCP packets don't overflow gso_segs - tcp-ao: fix use-after-free of current_key on reconnect to another peer - page_pool: remove zone/policy GFP flags when allocating XArray entries - Bluetooth: L2CAP: reject accept queue add unless BT_LISTEN - tls: device: fix out-of-bounds write in tls_append_frag() - eth: bnxt: - ring the doorbell when SW USO exits early, avoid packets stuck in Tx - gate TPH enablement behind BNXT_SUPPORTS_QUEUE_API check, avoid users of older NICs seeing non-actionable warning messages - eth: qede: fix NULL pointer dereference in TPA fragment processing" * tag 'net-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (216 commits) inet: frags: strip GSO state from fragments before reassembly net/sched: sch_htb: limit htb_classify inner-class filter hops selftests/net: packetdrill: add tcp_urg_ptr_retransmit tcp: fix corruption of urgent data on multi-segment retransmit usb: atm: usbatm: fix invalid ci_range initialization net: fec: only stop PTP if it was initialized slip: remove slip_hangup() to fix use-after-free in slip_receive_buf() net: bridge: mcast: fix use-after-free of a master VLAN's multicast context net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup net: dsa: mxl862xx: enable assisted learning on CPU port net: stmmac: restore NET_IP_ALIGN in the RX DMA offset net: stmmac: drop gso_enabled_types and rely on netdev features net: stmmac: selftests: Don't test flow control for small rx fifos net: stmmac: selftests: Account for the UC filter list for filtering tests net: stmmac: dwxgmac: Account for the primary MAC address for UC filtering net: stmmac: dwmac4: Account for the primary MAC address for UC filtering net: stmmac: dwmac1000: Account for the primary MAC address for UC filtering net: stmmac: selftests: Check multiple MMC counters selftests: net: Fix slow configurations in big_tcp_tunnels.sh selftests: net: Lower threshold with csum offload off in big_tcp_tunnels.sh ...
7 daysMerge tag 'nf-26-08-27' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nfJakub Kicinski26-319/+118
Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: 1) Use DEBUG_NET_WARN_ON_ONCE() instead of WARN_ON() from the tproxy datapath, a recent bug found a way to reach WARN_ON from datapath due to insufficient validation of xt_TPROTO checkentry. From Fernando F. Mancera. 2) Similar to previous patch to replace WARN_ON_ONCE by DEBUG_NET_WARN_ON_ONCE() for connlimit. Not known issue, but since this patch has been around for a while, let's merge it. Also from Fernando. 3) Move nf_tables harware offload commit path after chain blob and audit to reduce chances of leaving the hardware in inconsistent state. 4) Add missing vzeroupper to nf_tables pipapo AVX2 to address performace degradation to later user of SSE code, from Eric Biggers. 5) Remove pr_debug() in x_tables extensions, a recent bogus found a way to print a unsanitized string in xt_IDLETIMER, many of these pr_debug() calls are there for historical reasons. 6) Use pr_info_ratelimited() in x_tables .checkentry. 7) Fix an imbalance in module refcount due to incorrect override expression logic with sets. Remove unnecessary clone in control plane, use the existing expressions provided by set or dynset expression. Release override expressions only. 8) Tigthen nf_tables device name removal, it is possible to remove prefix strings with exact device name. From Fernando F. Mancera. 9) Set on the set dead bit earlier, otherwise it is possible to call .commit on deleted sets. This also addresses the re-introduction of a bug. * tag 'nf-26-08-27' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nf_tables: remove leftover set_update_list netfilter: nf_tables: set on dead bit when performing early element removal netfilter: nf_tables: skip double clone set expressions on element insert netfilter: x_tables: replace pr_{info,err}() by pr_info_ratelimited() netfilter: x_tables: remove pr_debug netfilter: nft_set_pipapo_avx2: add missing vzeroupper netfilter: nf_tables: move hardware offload step after building the chain blob netfilter: conncount: use DEBUG_NET_WARN_ON_ONCE on reaching count limit netfilter: tproxy: use DEBUG_NET_WARN_ON_ONCE for protocol fallbacks ==================== Link: https://patch.msgid.link/20260827141733.423453-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daysinet: frags: strip GSO state from fragments before reassemblyXinyang Ge1-0/+7
A virtio_net_hdr (tun/tap, or AF_PACKET with PACKET_VNET_HDR) can mark an IPv4 or IPv6 fragment as GSO; nothing relates gso_type to frag_off. inet_frag_reasm_prepare()/inet_frag_reasm_finish() keep the first fragment's skb as the head of the reassembled datagram, including its shinfo->gso_size/gso_type/gso_segs, and chain the remaining fragments on frag_list with whatever linear/paged layout they arrived with. After ip_defrag() (ip_local_deliver(), nf_defrag_ipv4, ...) the reassembled skb therefore still claims to be GSO (SKB_GSO_DODGY), and the next software segmentation point - udp_rcv_segment() on local delivery, validate_xmit_skb(), or the ip_finish_output_gso() slow path - hands it to skb_segment(). skb_segment()'s frag_list walk assumes GRO-shaped input and hits one of its BUG_ON()s. Two writes to a tap by an unprivileged user in its own userns are enough: kernel BUG at net/core/skbuff.c:4899! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 1000 PID: 82 Comm: poc Not tainted 7.2.0-pentest+ #2 RIP: 0010:skb_segment+0x20ca/0x48b0 Call Trace: <TASK> __udp_gso_segment+0x29a/0x27d0 udp4_ufo_fragment+0x458/0x6c0 inet_gso_segment+0x429/0x1340 skb_mac_gso_segment+0x233/0x4f0 __skb_gso_segment+0x308/0x660 udp_queue_rcv_skb+0x440/0xad0 udp_unicast_rcv_skb+0xc7/0x2c0 udp_rcv+0x16ce/0x2260 ip_protocol_deliver_rcu+0x197/0x2d0 ip_local_deliver+0x430/0x690 ip_rcv+0x16f/0x1f0 __netif_receive_skb_one_core+0x15e/0x1c0 __netif_receive_skb+0x1e/0x110 netif_receive_skb+0xf6/0x5c0 tun_rx_batched.isra.0+0x3ab/0x790 tun_get_user+0x17c3/0x3550 tun_chr_write_iter+0xba/0x1b0 vfs_write+0x646/0x1130 </TASK> Kernel panic - not syncing: Fatal exception in interrupt This runs with BH disabled, so it is a panic rather than an oops. The same is reachable with CAP_NET_RAW in a netns where a defrag point precedes a GSO point, and from a guest whose VMM forwards virtio_net_hdr to a tap. The SKB_GSO_DODGY frag_list checks added by commit 3dcbdb134f32 ("net: gso: Fix skb_segment splat when splitting gso_size mangled skb having linear-headed frag_list") and by commit 9e4b7a99a03a ("net: gso: fix panic on frag_list with mixed head alloc types") do not cover it: page-backed heads skip them, and kmalloc heads skip them when gso_size == skb_headlen(head), which the sender controls. An skb entering a frag queue is an IP fragment by definition and cannot legitimately carry GSO state: GRO does not merge fragments and the stack segments before it fragments, so only untrusted sources are affected. This has been reachable since commit f43798c27684 ("tun: Allow GSO using virtio_net_hdr"), the first path that let userspace attach GSO metadata to an IP fragment. Reset the GSO fields of every fragment as it is queued, in inet_frag_queue_insert(), which IPv4, IPv6, nf_conntrack_reasm and 6lowpan reassembly share; then neither the head nor the frag_list members of the reassembled skb carry them (the members matter too: the ip_do_fragment()/ip6_fragment() fast paths send them out as they are). The head may remain CHECKSUM_PARTIAL; that is already accepted on receive and resolved by skb_checksum_help() in ip_do_fragment()/ip6_fragment() on forward. Tested on top of net.git (dc4b95b8fee9), x86_64: the tap reproducer above, two further IPv4 frag_list geometries that reach BUG_ON(i >= nfrags) and BUG_ON(!list_skb->head_frag), and an IPv6 fragment-header variant (udp6_ufo_fragment()) each panic the unpatched kernel; with this patch all four datagrams are delivered intact and nothing is logged. Fixes: f43798c27684 ("tun: Allow GSO using virtio_net_hdr") Cc: stable@kernel.org Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Xinyang Ge <xinyang@anthropic.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/937926e509f2acd8e0e66520dc2b30fd6b4d1687.1787839506.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daysnet/sched: sch_htb: limit htb_classify inner-class filter hopsJamal Hadi Salim1-2/+5
htb_classify() follows each filter-selected inner class by switching to cl->filter_list, but never bounds the number of hops. A filter on an inner class can point back to itself or to another inner class that points back, creating an infinite loop in the packet classification path with the qdisc lock held and BH disabled — a soft lockup / panic from a single packet. Bound the traversal with a hop counter and drop the packet with a rate-limited warning once the bound is exceeded. The counter is incremented at the point the inner filter chain is picked up, after the TC_ACT_* switch has consumed the classifier verdict, so a terminal TC_ACT_QUEUED/STOLEN/TRAP on the last permitted chain still sets *qerr to __NET_XMIT_STOLEN and the packet is not charged as a drop by this qdisc or its parent. The bound is TC_HTB_MAXDEPTH, taken from HTB's own parameters rather than from the qdisc hierarchy depth limit. Class levels run from 0 to TC_HTB_MAXDEPTH - 1, so a traversal that strictly descends in level can take at most TC_HTB_MAXDEPTH hops. That descent is what a sane configuration does, but it is assumed here rather than enforced: htb_find() resolves a classid against every class in the qdisc, so a filter may equally select a sibling or an ancestor. The normal root -> inner -> leaf path takes a single hop, so the bound does not affect legitimate classification. htb_classify() can now return NULL irrespective of CONFIG_NET_CLS_ACT, whereas previously every NULL return sat inside that ifdef. The NULL handler in htb_enqueue() therefore cannot stay conditional either, so drop the ifdef around it. This matches hfsc_enqueue(), which has always handled a NULL class unconditionally. Without it, a kernel built without actions would dereference a NULL class instead of dropping. Conditions to recreate the bug: - CONFIG_NET_SCHED, CONFIG_NET_SCH_HTB, CONFIG_NET_CLS_U32, CONFIG_LOCKUP_DETECTOR. - Create an HTB qdisc on a device (e.g. lo), add an inner class 1:1 with a leaf child 1:10, install a root u32 filter selecting 1:1, and an inner-class u32 filter on 1:1 also selecting 1:1. - Send one packet (ping). On the unfixed kernel the classify loop spins with the qdisc lock held; with softlockup_panic=1 it panics. - Reachable from unprivileged user via unshare -Urn (CAP_NET_ADMIN). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Vega <vega@nebusec.ai> Co-developed-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260826143339.271935-1-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daystcp: fix corruption of urgent data on multi-segment retransmitJiayuan Chen1-1/+1
On the normal xmit path, while in urgent mode we refuse to build a multi-segment TSO packet, so every segment gets its own urg_ptr: /* tcp_write_xmit() */ limit = mss_now; if (tso_segs > 1 && !tcp_urg_mode(tp)) limit = tcp_mss_split_point(...); The retransmit path has no such guard. __tcp_retransmit_skb() builds a segs > 1 skb and hands it to the GSO layer, which only advances th->seq per segment and copies urg_ptr verbatim: /* __tcp_retransmit_skb() */ len = cur_mss * segs; /* segs > 1, no urg_mode check */ ... /* tcp_gso_segment(): bumps seq only, urg_ptr is copied */ urg_ptr is an offset from the segment's own seq, so a copied value points at a different place on each segment. The receiver rebuilds the absolute urgent seq as seg.seq + urg_ptr, so it walks a moving urgent point instead of the one OOB byte: seg1 seq 1 urg_ptr 5001 -> urgent @ 5001 (ok) seg2 seq 1001 urg_ptr 5001 -> urgent @ 6001 (wrong, +MSS) seg3 seq 2001 urg_ptr 5001 -> urgent @ 7001 (wrong, +2*MSS) The real OOB byte is never pointed at, so the receiver stops splicing it out and delivers it as normal in-band data, corrupting the stream. Guard the retransmit length like the xmit path: keep segs = 1 while in urgent mode. Fixes: 10d3be569243 ("tcp-tso: do not split TSO packets at retransmit time") Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260826141145.67823-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daysnet: bridge: mcast: fix use-after-free of a master VLAN's multicast contextNorbert Szetei1-2/+2
br_multicast_toggle_one_vlan() clears BR_VLFLAG_MCAST_ENABLED under br->multicast_lock before stopping a VLAN's multicast context. That is the teardown handshake: lockless readers gate on the flag through br_multicast_ctx_should_use() -> br_multicast_ctx_vlan_disabled(), so once it is cleared under the lock no reader can arm the context again. For a master VLAN the handshake never runs. __vlan_del() clears BRIDGE_VLAN_INFO_BRENTRY before calling br_vlan_put_master(), so br_multicast_toggle_one_vlan(masterv, false) returns early on !br_vlan_is_brentry(vlan): the flag stays set and br->multicast_lock is never taken. br_vlan_put_master() then drains the context in br_multicast_ctx_deinit() and frees the VLAN through call_rcu(), while a reader still inside rcu_read_lock() sees the context as enabled and re-arms it. The port and port-VLAN branch of the function has no br_vlan_is_brentry() test and flips the flag under br->multicast_lock, so it is not affected. The reader is the bridge transmit path. For a master VLAN br_multicast_rcv() selects brmctx = &vlan->br_mcast_ctx with pmctx = NULL, so IGMP sent to the bridge device re-arms the context's timers after br_multicast_ctx_deinit() has already stopped them. BUG: KASAN: slab-use-after-free in detach_if_pending+0x412/0x4a0 Write of size 8 at addr ffff88810ac39918 by task brmc/601 __mod_timer+0x51a/0xc50 br_multicast_host_join+0x25b/0x390 __br_multicast_add_group+0x468/0x530 br_ip4_multicast_add_group+0x1a0/0x260 br_multicast_rcv+0x2cda/0x61e0 br_dev_xmit+0x6c4/0x1540 Allocated by task 610: br_vlan_add+0x111/0xb40 br_vlan_info+0x370/0x3e0 Freed by task 0: kfree+0x1a7/0x4f0 rcu_core+0x7dc/0x10a0 Only test br_vlan_is_brentry() when enabling, like the br_multicast_ctx_vlan_global_disabled() test next to it. Disabling then always clears BR_VLFLAG_MCAST_ENABLED under br->multicast_lock before br_multicast_ctx_deinit() drains the context. Fixes: 7b54aaaf53cb ("net: bridge: multicast: add vlan state initialization and control") Cc: stable@vger.kernel.org Signed-off-by: Norbert Szetei <norbert@doyensec.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/D400F6C7-543A-4B79-9E5B-D1D8974DE5C9@doyensec.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
7 daysnet/sched: bound qdisc_pkt_len to prevent qdisc soft lockupJamal Hadi Salim1-2/+5
qdisc_get_stab() accepts a user-supplied size table, and __qdisc_calculate_pkt_len() amplifies qdisc_pkt_len() through the overhead, the size-table data (u16), and size_log (up to STAB_SIZE_LOG_MAX). A crafted stab can therefore set qdisc_pkt_len() to ~1 GiB for an ordinary skb. Per-flow deficit schedulers such as DRR and ETS replenish one quantum per loop iteration; with a tiny quantum (1) they spin billions of times under the qdisc lock, producing a soft lockup / RCU stall as illustrated by vega@nebusec.ai. Cap the final qdisc_pkt_len() to QDISC_PKT_LEN_MAX so the size-table amplification cannot drive deficit schedulers into an unbounded loop. A legitimate size table (e.g. qfq's overhead 999999999, which is handled by dropping) is still accepted. Introduce cap QDISC_PKT_LEN_MAX (1 << 20) = 1 MiB which is well above any legitimate single-skb wire length: the largest current skb->len is GSO_MAX_SIZE (524280), and an ATM-style size table (53/48 cell tax) amplifies that to ~578 KB, both comfortably below 1 MiB. At the same time, 1 MiB bounds the deficit refill loop to ~1M iterations per packet with quantum=1, which completes in a few milliseconds well under the demonstrated softlockup threshold (~10^9 iterations). Conditions to recreate the bug: - CONFIG_NET_SCHED=y, CONFIG_NET_SCH_DRR=y (or CONFIG_NET_SCH_ETS=y). - Attach a DRR (or ETS) root qdisc with a crafted TCA_STAB that amplifies qdisc_pkt_len to ~1 GiB (e.g. size_log=15, data=[32768]). - Add a class with a tiny quantum of 1 and send one small packet; the deficit loop spins billions of times under the qdisc lock and trips the softlockup detector (panic with kernel.softlockup_panic=1). - Reachable as root or from an unprivileged user in a fresh user+net namespace (unshare -Urn) with namespace-local CAP_NET_ADMIN. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260825081403.133992-1-jhs@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
8 daysnetfilter: nf_tables: remove leftover set_update_listPablo Neira Ayuso1-1/+0
This list has been moved to per-netns, remove onstack list which is not used anymore. Fixes: b343ededb3f9 ("netfilter: nf_tables: move set_update_list to nftables per-netns") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnetfilter: nf_tables: set on dead bit when performing early element removalPablo Neira Ayuso1-0/+4
.commit call for sets is skipped if set->dead flag is set on, but this flag is set on later in the commit path. This also reintroduces the bug fixed in commit 7315dc1e122c8 ("netfilter: nf_tables: skip set commit for deleted/destroyed sets"). Fixes: 1e3b9e1c77fe ("netfilter: nf_tables: call set ops .commit when building new ruleset blob") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnetfilter: nf_tables: skip double clone set expressions on element insertPablo Neira Ayuso2-48/+33
Both the dynset and newsetelem path clone the existing set expressions when setting set element expressions if no override expressions are provided. This results in a double clone, once to clone the template set expressions then another clone on the new element. Add a flag to annotate if userspace provides a override expression (ie. expression of the same type of the set but different configuration), otherwise borrow the existing expression from the set. Add conditionals to release expression iif they represent an override. Use this new override_exprs flag to dump the dynset expression override to userspace. This simplifies the existing logic and it also fixes a bug with the connlimit expression which results in a module refcount imbalance WARNING splat when resorting on the default set expressions. Fixes: 65038428b2c6 ("netfilter: nf_tables: allow to specify stateful expression in set definition") Fixes: fca05d4d61e6 ("netfilter: nft_dynset: honor stateful expressions in set definition") Reported-by: Xingyuan Mo <hdthky0@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnetfilter: x_tables: replace pr_{info,err}() by pr_info_ratelimited()Pablo Neira Ayuso2-8/+8
Several xtables extension still use pr_err() or pr_info() without ratelimit. For xt_cgroup, while at this, remove redundant "xt_cgroup:" prefix since pr_fmt is already set on. Fixes: c38c4597e4bf ("netfilter: implement xt_cgroup cgroup2 path match") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnetfilter: x_tables: remove pr_debugPablo Neira Ayuso18-246/+51
Remove pr_debug() for these xtables extensions, these have no use these days. Still, turn pr_debug() into pr_info_ratelimited() in the .checkentry path since this helps provide a hint via dmesg in legacy iptables. Exception is xt_IDLETIMER in the module init path, where pr_err() is used. Add missing pr_fmt() definition in xt_REDIRECT, xt_NETMAP and xt_MASQUERADE. Add missing \n to several pr_debug() that were translated to use pr_info_ratelimited(). Link: https://patch.msgid.link/cover.1786933680.git.rakukuip@gmail.com/ Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnetfilter: nft_set_pipapo_avx2: add missing vzeroupperEric Biggers1-9/+8
Since pipapo_get_avx2() uses YMM registers, execute vzeroupper before returning from it. This is needed to avoid degrading the performance of any later SSE code that may happen to be executed. Fixes: 7400b063969b ("nft_set_pipapo: Introduce AVX2-based lookup implementation") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnetfilter: nf_tables: move hardware offload step after building the chain blobPablo Neira Ayuso1-4/+10
Allocate the chain blob before the ruleset offload to reduce chances of entering an inconsistent state where the offloaded ruleset in the nic and the software ruleset differ. Fixes: c9626a2cbdb2 ("netfilter: nf_tables: add hardware offload support") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnet: Guard for gso_segs overflow in skb_segmentAlice Mikityanska1-1/+2
skb_segment calculates 32-bit partial_segs as len / gso_size, and then assigns it to the 16-bit gso_segs field. The division might overflow in some edge cases where the SKB is BIG TCP (65536 <= len <= 8*65535), and gso_size < TCP_MIN_GSO_SIZE = 8. While normally this can't happen due to TCP_MIN_GSO_SIZE, an AF_PACKET PACKET_VNET_HDR socket could generate such a malformed packet until the previous patch. Blocking malformed virtio_net packets was implemented in the previous patch, but this patch clamps partial_segs in skb_segment itself for more generic robustness. Should len / gso_size happen to be bigger than 65535 in partial GSO, skb_segment will now just produce more than two output SKBs, all of which will be valid with gso_segs <= 65535. In order to catch possible other cases of too many partial_segs, add a DEBUG_NET_WARN_ON_ONCE when len / gso_size happens to be too big. Signed-off-by: Alice Mikityanska <alice@isovalent.com> Link: https://patch.msgid.link/20260822120117.1163423-3-alice.kernel@fastmail.im Signed-off-by: Paolo Abeni <pabeni@redhat.com>
8 daysnetfilter: conncount: use DEBUG_NET_WARN_ON_ONCE on reaching count limitFernando Fernandez Mancera1-1/+2
Replace WARN_ON_ONCE with DEBUG_NET_WARN_ON_ONCE in __nf_conncount_add. The function handles count limit breaches safely by returning -EOVERFLOW, so a production backtrace is not needed. This prevents unnecessary system panics when panic_on_warn=1 is enabled in production systems. Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daysnetfilter: tproxy: use DEBUG_NET_WARN_ON_ONCE for protocol fallbacksFernando Fernandez Mancera2-2/+2
Replace WARN_ON calls with DEBUG_NET_WARN_ON_ONCE in the default switch blocks of nf_tproxy_get_sock_v4 and v6. Unsupported transport protocols are already safely handled by returning a NULL socket pointer. This prevents unnecessary system panics when panic_on_warn=1 is enabled in production systems. Link: https://patch.msgid.link/cover.1786968834.git.zhilinz@nebusec.ai/ Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
8 daystcp: fix AO info use-after-free in tcp_ao_connect_init()Qing Ming1-6/+1
tcp_v4_connect() adds a SYN-SENT socket to the ehash before calling tcp_connect(). If TCP-AO is configured, tcp_connect() first verifies that a key matches the peer and the bound device's current L3 master. tcp_ao_connect_init() later resolves the L3 master again and removes keys which do not match it. The socket lock does not stabilize the bound device's VRF membership. Detaching the device from its VRF between the initial validation and the L3-master calculation in tcp_ao_connect_init() can therefore make the validation succeed while initialization observes the default L3 domain and removes the only key. The subsequent AO lookup then fails, so the no-key path clears tp->ao_info and frees it directly. The receive path can find the socket in the ehash and load tp->ao_info under RCU before acquiring the socket lock. A reader which loaded the old pointer can thus continue into tcp_inbound_ao_hash() after the direct free. The issue was found during a static audit of TCP-AO object lifetime. An unprivileged reproducer in self-created user and network namespaces raced connect() with detaching a veth from its VRF while sending TCP-AO segments. It triggered the same KASAN report on two fresh boots: BUG: KASAN: slab-use-after-free in tcp_inbound_ao_hash+0x585/0x19f0 Write of size 8 at addr ffff88800bf88128 by task tcp_ao_vrf_race/232 Call Trace: tcp_inbound_ao_hash+0x585/0x19f0 tcp_inbound_hash+0x677/0xa80 tcp_v4_rcv+0x1c3e/0x3ab0 Allocated by task 235: tcp_ao_alloc_info+0x43/0xf0 tcp_ao_add_cmd+0xdf7/0x13b0 do_tcp_setsockopt+0x168c/0x2640 Freed by task 235: kfree+0x1b8/0x550 tcp_connect+0x252/0x4f00 tcp_v4_connect+0x1114/0x1720 The bad address is 40 bytes inside the freed 128-byte object, matching the tcp_ao_info counters.key_not_found field. The two runs used 1000 attempts each, reached the no-key path 366 and 411 times, and produced one and two KASAN reports respectively. With this change, the same reproducer reached the no-key path 366 times in 1000 attempts without a KASAN report or oops. Use tcp_ao_destroy_sock() for the no-key path. It unpublishes the AO info, updates the socket memory and static-key accounting, and defers the free until after an RCU grace period. Also drop the WARN_ON_ONCE() and its stale comment. The VRF detach race makes the no-key state reachable during normal operation, so it is a handled condition rather than an impossible assertion. On panic_on_warn kernels the WARN would turn this handled race into a kernel panic. Fixes: 248411b8cb89 ("net/tcp: Wire up l3index to TCP-AO") Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-5 Signed-off-by: Qing Ming <a0yami@mailbox.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260825072033.6921-1-a0yami@mailbox.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
8 daysnet/tcp: fix TCP-AO key deletion in VRFsRastislav Szabo1-0/+3
TCP-AO keys with TCP_AO_KEYF_IFINDEX store the VRF L3 interface index in l3index. tcp_ao_del_cmd() validates the supplied ifindex, but does not assign it to its local l3index before matching keys. As a result, deleting a key scoped to a non-default VRF always fails with ENOENT because it is matched against l3index 0. Fixes: 248411b8cb89 ("net/tcp: Wire up l3index to TCP-AO") Cc: stable@vger.kernel.org Signed-off-by: Rastislav Szabo <rastislav.szabo@isovalent.com> Reviewed-by: David Ahern <dsahern@kernel.org> Acked-by: Dmitry Safonov <0x7f454c46@gmail.com> Link: https://patch.msgid.link/20260822201119.272269-1-rastislav.szabo@isovalent.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
8 daysnet/smc: release the internal TCP sock on IPPROTO_SMC socket creation failureYifei Chu1-0/+16
IPPROTO_SMC sockets create an internal TCP sock ("clcsock") from the proto->init hook. When socket creation fails after proto->init has run - e.g. a cgroup BPF program attached to BPF_CGROUP_INET_SOCK_CREATE denies the socket - sk_common_release() only invokes sk_prot->destroy if it is set, but neither smc_inet_prot nor smc_inet6_prot defines it, and smc_destruct() returns early unless sk_state is SMC_CLOSED. As a result, every failing socket(AF_INET, SOCK_STREAM, IPPROTO_SMC) call leaks one tcp_sock, so an unprivileged task able to attach a deny-all BPF_CGROUP_INET_SOCK_CREATE program to its own cgroup can grow kernel memory unboundedly. Add a .destroy hook to both protos that releases the clcsock via smc_clcsock_release(). smc_sk_init() hashes the sock into the smc hashinfo before the clcsock is created, and smc_diag dumps walk that hash dereferencing smc->clcsock without taking clcsock_release_lock, while sk_common_release() calls .destroy before .unhash. Unhash the sock before releasing the clcsock, as __smc_release() does, so a concurrent dump cannot observe the release; the second unhash in sk_common_release() is a no-op. Fixes: d25a92ccae6b ("net/smc: Introduce IPPROTO_SMC") Reported-by: Abaci <abaci@linux.alibaba.com> Assisted-by: abaci:qwen3.8-max Signed-off-by: Yifei Chu <Chuyf26@linux.alibaba.com> Reviewed-by: Dust Li <dust.li@linux.alibaba.com> Link: https://patch.msgid.link/178753843966.342810.566471390946765094@linux.alibaba.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
8 daysnet: fix spurious TX timeout after dev_activate()Breno Leitao1-1/+1
While debugging another issue today, I found out that my TX queue is reported as stopped for 4294907392 ms (49.7 days), on a machine that had been up for four minutes. bnxt_en 0002:01:00.0 eth0: NETDEV WATCHDOG: CPU: 28: transmit queue 23 timed out 4294907392 ms 4294907392 is not an elapsed time. It is the value of jiffies at that moment: INITIAL_JIFFIES is 4294667296, which leaves jiffies 59 seconds short of wrapping. dev_activate() runs transition_one_qdisc() over every TX queue, which resets trans_start to 0, and then stamps only queue 0 through netif_trans_update(). Stamp jiffies instead. A queue stopped across dev_activate() now gets a full watchdog_timeo of grace, and is still reported if it is stopped that long. Fixes: 9b36627acecd ("net: remove dev->trans_start") Cc: stable@vger.kernel.org Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Nicolai Buchwitz <nb@tipi-net.de> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Link: https://patch.msgid.link/20260825-trans_start-v2-1-286b4d6d70cb@debian.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
8 daysMerge tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linuxLinus Torvalds1-3/+0
Pull hyperv updates from Wei Liu: - Decrypt netvsc buffer on contiguous direct-map addresses (Kameron Carr) - Drop WS2012/2012R2 & Win8/8.1 Hyper-V support (Michael Kelley) - Use more meaningful errnos for hypercall status code (Hardik Garg) - Fix lost interrupts on CPU hot-unplug for Hyper-V PCI/MSI (Naman Jain) - Reserve more MSHV vectors for Linux root partition (Wei Liu) * tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: clocksource: hyper-v: Remove support for stimer interrupts in message mode scsi: storvsc: Remove support for storvsc protocol of old Hyper-V hosts hv_netvsc: Remove GPADL teardown special case for old Hyper-V hosts hv_sock: Remove check for old Hyper-V hosts Drivers: hv: Remove support for WS2012/2012R2 & Win8/8.1 version of Hyper-V hv_netvsc: Allocate send/receive buffers using vmbus_alloc_buffer() Drivers: hv: vmbus: Add vmbus_alloc_buffer()/vmbus_free_buffer() for CoCo VMs Drivers: hv: vmbus: add vmbus_establish_gpadl_caller_decrypted() Drivers: hv: vmbus: Skip VMBus module cleanup for non-nested root partition x86/hyperv: reserve more vectors PCI: hv: Set irq_retrigger callback for the Hyper-V PCI MSI irqchip Drivers: hv: Use meaningful errnos for hypercall status codes
8 daysMerge tag 'nfs-for-7.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds3-15/+43
Pull NFS client updates from Trond Myklebust: "Highlights include: Stable fixes: - Use-after-free fixes for the sunrpc client code - Delegation hash table leak - NULL dereference on lockowner allocation failure - Fix a handshake completion race in the TLS code - Fix an error sign checking issue when deciding whether the pNFS layout is still in use, or can be returned - Fix a layout segment leak in pnfs_layout_process() Other bugfixes: - Fix a missing NULL check in the rpcbind client - annotate shared socket callbacks with READ_ONCE/WRITE_ONCE - nfs_inode_set_delegation() error paths should return the delegation - Use clear_and_wake_up_bit() in nfs_clear_invalid_mapping() and the pNFS code. - Fix the nfs4_alloc_client() error paths to free the IDR allocation - fix folio dereference before NULL check in nfs_inode_remove_request() - Fix delayed delegation return - Fix another state manager race with umount - Fix device leaks on parse failure - Avoid cancelling in-flight I/O during a layout recall if the server doesn't require it - flexfiles: report cancelled I/O as a layout error - flexfiles: fix NULL dereference for NFSv4.0 data servers - Fix incorrect argument passed to nfs4_delete_lease() - Fix several symlink issues resulting from nfs_atomic_open_v23() - Fix an uninitialised variable issue in the NFSv4.1 callback code - fix LAYOUTSTATS send buffer exhaustion Features and cleanups: - NFSv4.2: Allow the server to specify that file data may not be cached - localio: optimise I/O submission when when not doing memory reclaim - localio: Remove duplicate wait code in nfs_local_commit - flexfiles: support loosely coupled NFSv4.x data servers - pNFS: key the data server cache on the NFS version" * tag 'nfs-for-7.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (33 commits) NFSv4.1: fix layout segment leak on the pnfs_layout_process() forget path NFSv4/pnfs: key the data server cache on the NFS version NFSv4.2: fix LAYOUTSTATS send buffer exhaustion pNFS: Fix EBUSY check in pnfs_layout_need_return NFSv4.1: zero referring call lists before decoding nfs: fix ENXIO on O_CREAT open of existing symlink over NFSv3 SUNRPC: wait for in-flight client TLS handshake callback NFSv4: Fix incorrect argument passed to nfs4_delete_lease() in nfs4_add_lease() lockd: fix NULL dereference on lockowner allocation failure NFS: fix delegation_hash_table leak when nfs4_server_common_setup() fails NFSv4/flexfiles: support loosely coupled data servers NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers NFSv4: pin the superblock for active state owners sunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir NFS/localio: issue commit inline when not in a memory-reclaim context NFS/localio: remove dead FLUSH_SYNC handling from nfs_local_commit NFS/localio: issue IO inline when not in a memory-reclaim context NFS: Fix delayed delegation return list handling NFS: Verify symlink inode before caching target NFS: fix folio dereference before NULL check in nfs_inode_remove_request() ...
9 daysseg6: reset IP6CB after IPv6 decapsulationZhiling Zou1-0/+9
decap_and_validate() pulls the outer SRv6 headers and makes the inner packet the skb network header. The IPv6 control block still contains values collected while parsing the outer packet, including nhoff and extension-header flags. End.DX6 and End.DT6 route the inner IPv6 packet directly to the IPv6 input path. An unprivileged user can reach End.DT6 from a user and net namespace by installing a local SID and injecting an outer packet with Hop-by-Hop and Destination Options headers followed by an SRH and a minimal inner IPv6 packet. The outer extension headers leave a large nhoff in IP6CB. After decapsulation, ip6_protocol_deliver_rcu() uses that stale offset on the inner packet and reads beyond the skb head. KASAN reports: BUG: KASAN: slab-out-of-bounds in ip6_protocol_deliver_rcu ip6_protocol_deliver_rcu+0x1118/0x1450 ip6_input_finish+0x11b/0x240 seg6_local_input_core+0xed/0x2e0 lwtunnel_input+0x1e9/0x4e0 ipv6_rthdr_rcv+0x525f/0x6c50 ip6_protocol_deliver_rcu+0xcb7/0x1450 Before clearing IP6CB for an inner IPv6 packet, save its incoming interface index and L3 slave state. Restore both after the clear and set nhoff to the inner IPv6 base-header nexthdr field. Use IP6CB(skb)->iif rather than skb->skb_iif because VRF processing can replace skb_iif with the L3 master while IP6CB keeps the receiving interface. Preserve IP6SKB_L3SLAVE for the same reason. Fixes: d7a669dd2f8b ("ipv6: sr: add helper functions for seg6local") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai> Reviewed-by: Andrea Mayer <andrea.mayer@uniroma2.it> Signed-off-by: David S. Miller <davem@davemloft.net>
10 daysnet/sched: sch_teql: restore skb->dev on the slave failure pathVictor Nogueira1-0/+1
teql_master_xmit() sets skb->dev = slave before calling the slave's ndo_start_xmit(), but never restores it when that transmit fails. The skb then walks on to the next slave still pointing at the previous one. If a later slave has no resolved neighbour, teql_resolve() hands the skb to neigh_event_send(), which queues it on that neighbour's arp_queue with the stale skb->dev. skb->dev holds no reference, so deleting the previous slave frees the net_device while the skb is still queued. Whatever runs next on that skb - arp_error_report() on timeout, or neigh_direct_output() -> dev_queue_xmit() once the neighbour resolves - causes a UAF like the one below: BUG: KASAN: slab-use-after-free in __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) Read of size 4 at addr ffff888106e100b0 by task flood_packet/527 CPU: 0 UID: 0 PID: 527 Comm: flood_packet Not tainted 7.2.0-rc6-g594d90519502 #1 PREEMPT(lazy) 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 (lib/dump_stack.c:94 lib/dump_stack.c:120) print_report (mm/kasan/report.c:378 mm/kasan/report.c:482) ? __pfx__raw_spin_lock_irqsave (./include/asm-generic/qrwlock.h:122 (discriminator 4)) ? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) kasan_report (mm/kasan/report.c:595) ? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) [...] ipv4_link_failure (net/ipv4/route.c:1251 net/ipv4/route.c:1258) ? __pfx_ipv4_link_failure (./include/linux/skbuff.h:4327) ? _raw_write_lock (./include/linux/instrumented.h:55 ./include/linux/atomic/atomic-instrumented.h:1301 ./include/asm-generic/qrwlock.h:98 ./include/linux/rwlock_api_smp.h:230 kernel/locking/spinlock.c:304) ? __pfx__raw_write_lock (kernel/locking/spinlock.c:175) arp_error_report (./include/net/dst.h:438 net/ipv4/arp.c:296) neigh_invalidate (net/core/neighbour.c:1077) neigh_timer_handler (net/core/neighbour.c:1169) [...] Allocated by task 505: kasan_save_stack (mm/kasan/common.c:57) kasan_save_track (mm/kasan/common.c:78) __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415) __kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5334 mm/slub.c:6905) alloc_netdev_mqs (net/core/dev.c:12055 (discriminator 2)) rtnl_create_link (net/core/rtnetlink.c:3721) rtnl_newlink (net/core/rtnetlink.c:3903 net/core/rtnetlink.c:4044 net/core/rtnetlink.c:4159) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) [...] Freed by task 536: kasan_save_stack (mm/kasan/common.c:57) kasan_save_track (mm/kasan/common.c:78) kasan_save_free_info (mm/kasan/generic.c:584) __kasan_slab_free (mm/kasan/common.c:253 mm/kasan/common.c:285) kfree (./include/linux/kasan.h:235 mm/slub.c:2677 mm/slub.c:6377 mm/slub.c:6692) device_release (drivers/base/core.c:2636) kobject_put (lib/kobject.c:689 lib/kobject.c:720 ./include/linux/kref.h:65 lib/kobject.c:737) netdev_run_todo (net/core/dev.c:11756) rtnl_dellink (net/core/rtnetlink.c:157 ./include/linux/rtnetlink.h:135 net/core/rtnetlink.c:3651) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) [...] Fix this by restoring skb->dev to the master at the end of each slave's iteration. Fixes: 0cc0c2e661af ("net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit") Reported-by: Vega <vega@nebusec.ai> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260824115928.4099988-1-victor@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 dayssctp: fix stream->outcnt underflow on duplicate RECONF responsesJun Yang1-11/+28
A cached RECONF chunk may contain more than one request parameter. A duplicate response can therefore find and process the same ADD_OUT request again while another parameter is still outstanding, rolling back outcnt twice and possibly underflowing it. Track outstanding request types as bits and clear each bit after its first response. Later responses for the same request are then ignored. Fixes: 11ae76e67a17 ("sctp: implement receiver-side procedures for the Reconf Response Parameter") Cc: stable@kernel.org Reported-by: TencentOS Corvus AI <corvus@tencent.com> Link: https://lore.kernel.org/netdev/20260730110225.37371-1-juny24602@gmail.com/ Suggested-by: Xin Long <lucien.xin@gmail.com> Assisted-by: tencentos-corvus-ai:kimi-k3 Signed-off-by: Jun Yang <junvyyang@tencent.com> Link: https://patch.msgid.link/20260824081832.98717-3-juny24602@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 dayssctp: distinguish sequence zero from wildcard in reconf lookupJun Yang1-5/+6
Zero is a valid response sequence after strreset_outseq wraps, but sctp_chunk_lookup_strreset_param() currently treats it as a wildcard. Add match_seq so response lookups match zero exactly while the one type-only lookup can still ignore the sequence. Fixes: 50a41591f110 ("sctp: implement receiver-side procedures for the Add Outgoing Streams Request Parameter") Cc: stable@kernel.org Suggested-by: Simon Horman <horms@kernel.org> Acked-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Jun Yang <junvyyang@tencent.com> Link: https://patch.msgid.link/20260824081832.98717-2-juny24602@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet/sched: sfq: clamp quantum to avoid signed overflow soft lockupJamal Hadi Salim1-1/+2
sfq_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) (unsigned). A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000, so slot->allot = INT_MIN and INT_MIN + INT_MIN toggles between INT_MIN and 0 forever, spinning sfq_dequeue() under the qdisc lock. Clamp the quantum to [256, 1 << 20] so the refill loop terminates. The lower bound also covers q->quantum == 0 (psched_mtu() returning 0), which spins sfq_dequeue() identically. sfq_change() already rejects a negative quantum, so only the init path was exposed. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260822195509.112717-7-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet/sched: hhf: clamp quantum before hhf_change() to avoid overflowJamal Hadi Salim1-0/+4
hhf_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) with no overflow check. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes weight * quantum overflow the signed deficit in hhf_dequeue(), spinning forever. Clamp q->quantum before hhf_change() so both the opt and !opt paths see a sane quantum. Without this, bare "tc qdisc add ... hhf" succeeds with a clamped quantum but "tc qdisc add ... hhf limit 1000" (any option present) fails with -EINVAL because hhf_change() re-validates the unclamped default (sch_hhf.c:559). 256 matches fq_codel's floor and is a sane minimum for a DRR quantum. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace. Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260822195509.112717-6-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet/sched: fq_pie: clamp default quantum to avoid signed overflowJamal Hadi Salim1-1/+2
fq_pie_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000, which overflows the signed flow->deficit to INT_MIN in fq_pie_qdisc_dequeue(), causing an infinite loop and soft lockup. Emulate fq_pie_policy which is already bounded to [1, 1 << 20]; clamp the default to [256, 1 << 20]. 256 matches fq_codel's floor and is a sane minimum for a DRR quantum. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace. Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260822195509.112717-5-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet/sched: sch_codel: clamp default mtu to avoid disabling CoDelJamal Hadi Salim1-1/+1
codel_init() sets q->params.mtu = psched_mtu(qdisc_dev(sch)) without clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000. In codel_should_drop() the test "*backlog <= params->mtu" then compares the backlog against ~2 GiB; with the default sch->limit of DEFAULT_CODEL_LIMIT (1000) packets the backlog can never reach it, so the test is always true and CoDel is silently and completely disabled i.e no drops, no ECN marking, codel degrades to a tail-drop FIFO. codel_change() never updates params.mtu, so the init path is the only place to clamp it. Constrain to [256, 1 << 20], matching the fq_codel bound; 256 is a sane floor that only makes CoDel slightly more willing to act on very small queues, which is the safe direction. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace. Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260822195509.112717-4-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet/sched: fq_codel: clamp default quantum and mtuJamal Hadi Salim1-2/+4
fq_codel_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000, which overflows the signed flow->deficit to INT_MIN in fq_codel_dequeue(), causing an infinite loop and soft lockup. Emulate fq_codel_change() and constrain to [256, FQ_CODEL_QUANTUM_MAX]. The same unclamped psched_mtu() is assigned to q->cparams.mtu a bit below, and fq_codel_change() never updates it. codel_should_drop() tests "*backlog <= params->mtu"; with mtu == 0x80000000 (~2 GiB) and the default 32 MiB memory_limit, the test is always true, so CoDel is silently and completely disabled (no drops, no ECN). Declare a single clamped mtu and assign both q->quantum and q->cparams.mtu from it, which also removes the double psched_mtu() call. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace. Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260822195509.112717-3-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet/sched: fq: add overflow bounds to quantum and initial quantumJamal Hadi Salim1-2/+4
fq_init() computes quantum = 2 * psched_mtu() and initial_quantum = 10 * psched_mtu() with no overflow check. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000; the 2 * and 10 * multiplications wrap to 0 in 32-bit arithmetic, so q->quantum == 0. Then in fq_dequeue() the credit-refill loop adds 0 to f->credit (which stays <= 0) and goto begin loops forever under the qdisc lock, creating a soft lockup. Clamp psched_mtu() to [1, 1 << 20] before multiplying so the product cannot wrap, then cap the result at 1 << 20, matching the bound already enforced on TCA_FQ_QUANTUM in fq_change(). Conditions to recreate the bug: a device whose MTU (plus hard_header_len) is large enough that 2 * psched_mtu() wraps (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace. Fixes: afe4fd062416 ("pkt_sched: fq: Fair Queue packet scheduler") Reported-by: vega@nebusec.ai Tested-by: Victor Nogueira <victor@mojatatu.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260822195509.112717-2-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysvsock/virtio: flush works in dependency orderChengfeng Ye1-1/+1
virtio_vsock_remove() stops the virtqueues and then flushes each work item before freeing the enclosing virtio_vsock. The current order does not account for dependencies between those items: tx_work may queue send_pkt_work, and send_pkt_work may queue rx_work. In particular, send_pkt_work can set restart_rx and release tx_lock. The remove path can then stop the queues and flush rx_work before send_pkt_work queues it. Although the later send_pkt_work flush waits for that producer to finish, nothing waits for the newly queued rx_work, so kfree(vsock) can race with it. KASAN reported: BUG: KASAN: slab-use-after-free in virtio_transport_rx_work+0x487/0x4b0 Read of size 8 at addr ffff888114c2b008 by task kworker/1:1/47 Workqueue: virtio_vsock virtio_transport_rx_work Call Trace: virtio_transport_rx_work+0x487/0x4b0 process_one_work+0x688/0x1120 worker_thread+0x45b/0xd10 Allocated by task 1: virtio_vsock_probe+0xef/0x6b0 Freed by task 84: kfree+0x131/0x3c0 virtio_vsock_remove+0xd1/0x100 Flush the works in producer-to-consumer order. virtio_vsock_vqs_del() has already disabled the queue callbacks and cleared the run flags, so after tx_work and send_pkt_work are drained, no source remains that can queue rx_work after its flush. Fixes: 0ea9e1d3a9e3 ("VSOCK: Introduce virtio_transport.ko") Cc: stable@vger.kernel.org Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com> Link: https://patch.msgid.link/20260822164556.3750959-1-nicoyip.dev@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet: fix a resource leak in copy_net_ns() error handling pathTetsuo Handa1-12/+9
Currently, preinit_net() does two things: (1) call ns_common_init() which might fail (2) initialize resources which does not fail However, preinit_net() is returning early when (1) fails, and copy_net_ns() is jumping to the dec_ucounts: label. As a result, resources allocated by net_alloc() are leaking. We need to call key_remove_domain() and net_passive_dec() in order to release resources allocated by net_alloc(). We cannot simply jump to the put_userns: label when preinit_net() failed, for (2) is not yet done. But we can reorder (1) and (2), for there is no dependency between (1) and (2). Therefore, this patch decouples (1) from preinit_net() and changes preinit_net() back to a void function, and calls ns_common_init() after preinit_net() succeeded. Then, we can jump to immediately after ns_common_free() of the put_userns: label. Reported-by: sashiko (no mail address) Closes: https://sashiko.dev/#/patchset/af7dabf3-d0d7-46dc-a878-e1715b3c9ac6%40I-love.SAKURA.ne.jp Fixes: 08027f6b790b ("net: use ns_common_init()") Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://patch.msgid.link/c182cf90-1ed7-435b-88f7-9f00e88a0487@I-love.SAKURA.ne.jp Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet: core: fix head-page leak in skb_zerocopyMina Almasry1-2/+2
When skb_orphan_frags() throws -ENOMEM, skb_copy_ubufs() may have already reallocated and replaced 'from->head'. Accessing from->head to drop the old refcount leaks the original head page, and erroneously puts an unrelated new buffer. Use the local 'page' tracker variable instead to drop the reference properly. Fixes: 36d5fe6a0007 ("core, nfqueue, openvswitch: Orphan frags in skb_zerocopy and handle errors") Signed-off-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/20260823183602.1051453-2-almasrymina@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
10 daysnet: core: check skb_frags_readable before uncloning in skb_copy_ubufsMina Almasry1-3/+3
skb_copy_ubufs drops clones and modifies the SKB via pskb_expand_head() before checking for !skb_frags_readable(skb). This alters the SKB geometry prior to throwing an -EFAULT on an invalid SKB. Check readability first. Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags") Signed-off-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/20260823183602.1051453-1-almasrymina@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>