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2026-06-14netfilter: nf_conncount: callers must hold rcu read lockFlorian Westphal2-4/+4
rcu_derefence_raw() should not have been used here, it concealed this bug. Its used because struct rb_node lacks __rcu annotated pointers, so plain rcu_derefence causes sparse warnings. The major tradeoff is that rcu_derefence_raw() doesn't warn when the caller isn't in a rcu read section. Extend the rcu read lock scope accordingly and cause sparse warnings, those warnings are the lesser evil. Fixes: 11efd5cb04a1 ("openvswitch: Support conntrack zone limit") Closes: https://sashiko.dev/#/patchset/20260603230610.7900-1-fw%40strlen.de Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-06-14netfilter: nf_tables: use DEBUG_NET_WARN_ON_ONCE in packet and control pathsFernando Fernandez Mancera22-46/+76
Replace raw warning macros with DEBUG_NET_WARN_ON_ONCE across the nf_tables API, core engine, and expression evaluations. 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>
2026-06-14ipvs: Replace use of system_unbound_wq with system_dfl_long_wqMarco Crivellari2-7/+7
This patch continues the effort to refactor workqueue APIs, which has begun with the changes introducing new workqueues and a new alloc_workqueue flag: commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") The point of the refactoring is to eventually alter the default behavior of workqueues to become unbound by default so that their workload placement is optimized by the scheduler. Before that to happen, workqueue users must be converted to the better named new workqueues with no intended behaviour changes: system_wq -> system_percpu_wq system_unbound_wq -> system_dfl_wq This way the old obsolete workqueues (system_wq, system_unbound_wq) can be removed in the future. This specific work is considered long, so enqueue it using system_dfl_long_wq instead of system_dfl_wq. Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/ Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Marco Crivellari <marco.crivellari@suse.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-06-14batman-adv: tvlv: avoid race of cifsnotfound handler stateSven Eckelmann2-13/+57
TVLV handlers can have the flag BATADV_TVLV_HANDLER_OGM_CIFNOTFND set to signal that the OGM handler should be called (with NULL for data) when the specific TVLV container was not found in the OGM. This is used by: * DAT * GW * Multicast (OGM + Tracker) The state whether the handler was executed was stored in the struct batadv_tvlv_handler. But the TVLV processing is started without any lock. Multiple parallel contexts processing TVLVs would therefore overwrite each others BATADV_TVLV_HANDLER_OGM_CALLED flag in the shared batadv_tvlv_handler. Drop the shared BATADV_TVLV_HANDLER_OGM_CALLED flag and instead determine, per TVLV buffer, whether a matching container was present by scanning the packet's buffer. Cc: stable@kernel.org Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-14batman-adv: tvlv: enforce 2-byte alignmentSven Eckelmann4-2/+32
The fields of an aggregated OGM(v2) are accessed assuming (at least) 2-byte alignment, so a following OGM must start at an even offset. As the header length is even, an odd tvlv_len would misalign it and trigger unaligned accesses on strict-alignment architectures. Such a misaligned TVLV/OGM/OGMv2 is not created by a normal participant in the mesh. Therefore, reject such malformed packets. Cc: stable@kernel.org Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-14kcm: use WRITE_ONCE() when changing lower socket callbacksRunyu Xiao1-4/+4
kcm_attach() replaces a live lower TCP socket's sk_data_ready and sk_write_space callbacks with KCM handlers, and kcm_unattach() restores them later. Those callback-pointer updates are still plain stores even though the same fields can be read and invoked concurrently on other CPUs. If another CPU observes an older callback snapshot after the live field has already been restored, callback execution can run with a mismatched target and sk_user_data state, leading to stale or misdirected wakeups. Use WRITE_ONCE() for the callback replacement and restore operations so these shared callback fields follow the same visibility contract already established by the earlier 4022 fixes. Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module") Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn> Link: https://patch.msgid.link/20260611053543.2429462-1-runyu.xiao@seu.edu.cn Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-06-14batman-adv: dat: prevent false sharing between VLANsSven Eckelmann1-3/+9
The local hash of DAT entries is supposed to be VLAN (VID) aware. But the adding to the hash and the search in the hash were not checking the VID information of the hash entries. The entries would therefore only be correctly separated when batadv_hash_dat() didn't select the same buckets for different VIDs. Cc: stable@kernel.org Fixes: be1db4f6615b ("batman-adv: make the Distributed ARP Table vlan aware") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-14batman-adv: tt: track roam count per VIDSven Eckelmann2-2/+10
batadv_tt_check_roam_count() is supposed to track roaming of a TT entry. But TT entries are for a MAC + VID. The VID was completely missed and thus leads to incorrect detection of ROAM counts when a client MAC exists in multiple VLANs. Cc: stable@kernel.org Fixes: c018ad3de61a ("batman-adv: add the VLAN ID attribute to the TT entry") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-14batman-adv: tt: don't merge change entries with different VIDsSven Eckelmann1-0/+3
batadv_tt_local_event() merges/cancels events for the same client which would conflict or be duplicates. The matching of the queued events only compares the MAC address - the VLAN ID stored in each event is ignored. If a MAC would now appear on multiple VID, the two ADD change events (for VID 1 and VID 2) would be merged to a single vid event. The remote can therefore not calculate the correct TT table and desync. A full translation table exchange is required to recover from this state. A check of VID is therefore necessary to avoid such wrong merges/cancels. Cc: stable@kernel.org Fixes: c018ad3de61a ("batman-adv: add the VLAN ID attribute to the TT entry") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13net: ife: require ETH_HLEN to be pullable in ife_decode()Yong Wang1-1/+1
ife decode may return after making only the outer IFE header and metadata pullable. The caller then passes the decapsulated packet to eth_type_trans(), which expects the inner Ethernet header to be accessible from the linear data area. With a malformed IFE frame, the inner Ethernet header may still be shorter than ETH_HLEN in the linear area, which can lead to a crash in the original code. Fix this by extending the pull check in ife_decode() so that the inner Ethernet header is also guaranteed to be pullable before returning. Fixes: ef6980b6becb ("introduce IFE action") Cc: stable@vger.kernel.org Reported-by: Yuan Tan <yuantan098@gmail.com> Reported-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Yong Wang <edragain@163.com> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Link: https://patch.msgid.link/20260610183814.1648888-2-n05ec@lzu.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13devlink: Implement devlink param multi attribute nested data valuesSaeed Mahameed2-1/+34
Devlink param value attribute is not defined since devlink is handling the value validating and parsing internally, this allows us to implement multi attribute values without breaking any policies. Devlink param multi-attribute values are considered to be dynamically sized arrays of u64 values, by introducing a new devlink param type DEVLINK_PARAM_TYPE_U64_ARRAY, driver and user space can set a variable count of u64 values into the DEVLINK_ATTR_PARAM_VALUE_DATA attribute. Implement get/set parsing and add to the internal value structure passed to drivers. This is useful for devices that need to configure a list of values for a specific configuration. example: $ devlink dev param show pci/... name multi-value-param name multi-value-param type driver-specific values: cmode permanent value: 0,1,2,3,4,5,6,7 $ devlink dev param set pci/... name multi-value-param \ value 4,5,6,7,0,1,2,3 cmode permanent Signed-off-by: Saeed Mahameed <saeedm@nvidia.com> Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com> Link: https://patch.msgid.link/20260609040453.711932-5-rkannoth@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13devlink: heap-allocate param fill buffers in devlink_nl_param_fillRatheesh Kannoth1-16/+46
devlink_nl_param_fill() kept two per-configuration-mode copies of union devlink_param_value plus a struct devlink_param_gset_ctx on the stack while building the Netlink reply. Allocate those with kcalloc() and kzalloc_obj() instead, and route failures through a single cleanup path so temporary buffers are always freed. Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com> Link: https://patch.msgid.link/20260609040453.711932-4-rkannoth@marvell.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13tipc: restrict socket queue dumps in enqueue tracepointsLi Xiasong1-3/+3
tipc_sk_enqueue() runs with sk->sk_lock.slock held while the socket is owned by user context. The spinlock protects the backlog queue in this path, but it does not serialize against the socket owner consuming or purging sk_receive_queue. KASAN reported: CPU: 14 UID: 0 PID: 1050 Comm: tipc3 Not tainted 7.1.0-rc6+ #126 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x76/0xa0 lib/dump_stack.c:123 print_report+0xce/0x5b0 mm/kasan/report.c:482 kasan_report+0xc6/0x100 mm/kasan/report.c:597 __asan_report_load4_noabort+0x14/0x30 mm/kasan/report_generic.c:380 tipc_skb_dump+0x1327/0x16f0 net/tipc/trace.c:73 tipc_list_dump+0x208/0x2e0 net/tipc/trace.c:187 tipc_sk_dump+0xaf6/0xd60 net/tipc/socket.c:3996 trace_event_raw_event_tipc_sk_class+0x312/0x5a0 net/tipc/trace.h:188 tipc_sk_rcv+0xb1d/0x1d50 net/tipc/socket.c:2497 tipc_node_xmit+0x1c3/0x1440 net/tipc/node.c:1689 __tipc_sendmsg+0x97a/0x1440 net/tipc/socket.c:1512 tipc_sendmsg+0x52/0x80 net/tipc/socket.c:1400 sock_sendmsg+0x2f6/0x3e0 net/socket.c:825 splice_to_socket+0x7f9/0x1010 fs/splice.c:884 do_splice+0xe21/0x2330 fs/splice.c:936 __do_splice+0x153/0x260 fs/splice.c:1431 __x64_sys_splice+0x150/0x230 fs/splice.c:1616 x64_sys_call+0xeb5/0x2790 arch/x86/entry/syscall_64.c:41 do_syscall_64+0xf3/0x620 arch/x86/entry/syscall_64.c:63 entry_SYSCALL_64_after_hwframe+0x76/0x7e arch/x86/entry/entry_64.S:130 RIP: 0033:0x71624e8aafe2 Code: 08 0f 85 71 3a ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 66 2e 0f 1f 84 00 00 00 00 00 66 RSP: 002b:0000716157ffed68 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 0000716157fff6c0 RCX: 000071624e8aafe2 RDX: 000000000000005f RSI: 0000000000000000 RDI: 0000000000000066 RBP: 0000716157ffed90 R08: 0000000000008000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffff00 R13: 0000000000000021 R14: 0000000000000000 R15: 00007fff89799c40 </TASK> The TIPC_DUMP_ALL tracepoints in tipc_sk_enqueue() also dump sk_receive_queue and can therefore dereference skbs that the socket owner has already dequeued or freed. Restrict these dumps to TIPC_DUMP_SK_BKLGQ, which matches the queue protected by the held spinlock. Keep the change limited to the enqueue path, where the unsafe queue dump is reachable while the socket is owned by user context. Fixes: 01e661ebfbad ("tipc: add trace_events for tipc socket") Cc: stable@vger.kernel.org Signed-off-by: Li Xiasong <lixiasong1@huawei.com> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Link: https://patch.msgid.link/20260611135647.3666727-1-lixiasong1@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13ipv4: handle devconf post-set actions on netlink updatesFernando Fernandez Mancera1-2/+27
When IPv4 device configuration parameters are updated via netlink, the kernel currently only updates the value. This bypasses several post-modification actions that occur when these same parameters are updated via sysctl, such as flushing the routing cache or emitting RTM_NEWNETCONF notifications. This patch addresses the inconsistency by calling the devinet_conf_post_set() helper inside inet_set_link_af(). If a flush is required, we defer it until the netlink attribute parsing loop completes. This ensures consistent behavior and side-effects for devconf changes, regardless of whether they are initiated via sysctl or netlink. Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de> Link: https://patch.msgid.link/20260609204520.4670-2-fmancera@suse.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13ipv4: centralize devconf sysctl handlingFernando Fernandez Mancera1-59/+68
The logic for handling IPv4 devconf sysctls is scattered. Notification and cache flushes are managed in devinet_conf_proc(), while a separate ipv4_doint_and_flush() function and DEVINET_SYSCTL_FLUSHING_ENTRY macro is used for properties that solely require a cache flush. This patch refactors the sysctl handling by introducing a centralized helper, devinet_conf_post_set(). This new function evaluates the changed attribute and handles all necessary operations like triggering netlink notifications. It returns a boolean indicating whether a routing cache flush is required. Note that the boolean is necessary as this function will be re-used for netlink IPv4 devconf handling where the cache flushing must wait until all the attributes have been processed. Finally, this is introducing a small change in behavior for IPV4_DEVCONF_ROUTE_LOCALNET. As commit d0daebc3d622 ("ipv4: Add interface option to enable routing of 127.0.0.0/8") intended, the cache flush should only be performed when ROUTE_LOCALNET changes from 1 to 0. Unfortunately, this was not true because while implementing it the DEVINET_SYSCTL_FLUSHING_ENTRY was used for the attribute, making the code related to it on devinet_conf_proc() dead. IPV4_DEVCONF_FORWARDING is still being handled separately as it requires more operations. Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de> Link: https://patch.msgid.link/20260609204520.4670-1-fmancera@suse.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13tcp: refine tcp_sequence() for the FIN exceptionEric Dumazet1-3/+5
Commit 0e24d17bd966 ("tcp: implement RFC 7323 window retraction receiver requirements") removed the special FIN case that was added in commit 1e3bb184e941 ("tcp: re-enable acceptance of FIN packets when RWIN is 0"). If a peer sends a segment containing data and a FIN flag before it learns about our window retraction and has a buggy TCP stack, it might place the FIN one byte beyond what it thinks is the right edge of the window (i.e., max_window_edge + 1). The data portion (end_seq - th->fin) will end exactly at max_window_edge. In this case, we will drop the packet if our receive queue is not empty, even though the data was sent within the window we previously allowed. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Simon Baatz <gmbnomis@gmail.com> Link: https://patch.msgid.link/20260608151452.706822-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13Merge tag 'ipsec-next-2026-06-12' of ↵Jakub Kicinski8-125/+548
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2026-06-12 1) Replace the open-coded manual cleanup in xfrm_add_policy() error path with xfrm_policy_destroy() for consistency with xfrm_policy_construct(). From Deepanshu Kartikey. 2) Limit XFRMA_TFCPAD to a sensible maximum (max IP length, 64k) since u32 is excessive for traffic flow confidentiality padding. From David Ahern. 3) Add a new netlink message XFRM_MSG_MIGRATE_STATE that allows migrating individual IPsec SAs independently of their policies. The existing XFRM_MSG_MIGRATE is tightly coupled to policy+SA migration, lacks SPI for unique SA identification, and cannot express reqid changes or migrate Transport mode selectors. The new interface identifies the SA via SPI and mark, supports reqid changes, address family changes, encap removal, and uses an atomic create+install flow under x->lock to prevent SN/IV reuse during AEAD SA migration. From Antony Antony. * tag 'ipsec-next-2026-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next: xfrm: add documentation for XFRM_MSG_MIGRATE_STATE xfrm: restrict netlink attributes for XFRM_MSG_MIGRATE_STATE xfrm: add XFRM_MSG_MIGRATE_STATE for single SA migration xfrm: make xfrm_dev_state_add xuo parameter const xfrm: extract address family and selector validation helpers xfrm: refactor XFRMA_MTIMER_THRESH validation into a helper xfrm: move encap and xuo into struct xfrm_migrate xfrm: add error messages to state migration xfrm: add state synchronization after migration xfrm: check family before comparing addresses in migrate xfrm: split xfrm_state_migrate into create and install functions xfrm: rename reqid in xfrm_migrate xfrm: fix NAT-related field inheritance in SA migration xfrm: allow migration from UDP encapsulated to non-encapsulated ESP xfrm: add extack to xfrm_init_state xfrm: remove redundant assignments xfrm: Reject excessive values for XFRMA_TFCPAD xfrm: cleanup error path in xfrm_add_policy() ==================== Link: https://patch.msgid.link/20260612074725.1760473-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13vsock: fold sk_acceptq_removed() into vsock_remove_pending()Raf Dickson2-5/+2
Callers of vsock_remove_pending() must also call sk_acceptq_removed() to keep sk_ack_backlog consistent. Move the call into vsock_remove_pending() itself to make it automatic and prevent future callers from forgetting it. Suggested-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Raf Dickson <rafdog35@gmail.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Luigi Leonardi <leonardi@redhat.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Link: https://patch.msgid.link/20260612045216.105796-5-rafdog35@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13vsock: fold sk_acceptq_added() into vsock_enqueue_accept()Raf Dickson3-2/+1
virtio and hyperv call sk_acceptq_added() immediately before vsock_enqueue_accept(). Move the call into vsock_enqueue_accept() itself so callers cannot forget it and the accounting is consistent. Suggested-by: Paolo Abeni <pabeni@redhat.com> Suggested-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Raf Dickson <rafdog35@gmail.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Luigi Leonardi <leonardi@redhat.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Link: https://patch.msgid.link/20260612045216.105796-4-rafdog35@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13vsock: fold sk_acceptq_added() into vsock_add_pending()Raf Dickson2-1/+1
Move sk_acceptq_added() into vsock_add_pending() so callers cannot forget it. vmci is the only transport using the pending list and is updated accordingly. Suggested-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Raf Dickson <rafdog35@gmail.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Luigi Leonardi <leonardi@redhat.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Link: https://patch.msgid.link/20260612045216.105796-3-rafdog35@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13vsock: introduce vsock_pending_to_accept() helperRaf Dickson2-2/+11
Add vsock_pending_to_accept() to move a socket directly from the pending list to the accept queue in a single operation, avoiding the sock_put/sock_hold dance and the sk_acceptq_removed()/ sk_acceptq_added() pair that would otherwise be needed when calling vsock_remove_pending() followed by vsock_enqueue_accept(). Use it in vmci_transport_recv_connecting_server() where a completed handshake transitions the socket from pending to accept queue. Suggested-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Raf Dickson <rafdog35@gmail.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Luigi Leonardi <leonardi@redhat.com> Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com> Link: https://patch.msgid.link/20260612045216.105796-2-rafdog35@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13vsock: use sk_acceptq_is_full() helper in all transportsRaf Dickson2-2/+2
Replace the open-coded backlog check with sk_acceptq_is_full(). The helper uses > instead of >=, which is the correct comparison per commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes."), and adds READ_ONCE() for proper memory ordering. Suggested-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Raf Dickson <rafdog35@gmail.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Luigi Leonardi <leonardi@redhat.com> Link: https://patch.msgid.link/20260612045842.122207-1-rafdog35@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-13batman-adv: tp_meter: handle overlapping packetsSven Eckelmann1-14/+11
If the size of the packets would change during the transmission, it could happen that some retries of packets are overlapping. In this case, precise comparisons of sequence numbers by the receiver would be wrong. It is then necessary to check if the start sequence number to the end sequence number ("seqno + length") would contain a new range. If this is the case then this is enough to accept this packet. In all other cases, the packet still has to be dropped (and not acked). Cc: stable@kernel.org Fixes: 33a3bb4a3345 ("batman-adv: throughput meter implementation") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: tp_meter: prevent parallel modifications of last_recvSven Eckelmann2-10/+14
When last_recv is updated to store the last receive sequence number, it is assuming that nothing is modifying in parallel while: * check for outdated packets is done * out of order check is performed (and packets are stored in out-of-order queue) * the out-of-order queue was searched for closed gaps * sequence number for next ack is calculated Nothing of that was actually protected. It could therefore happen that the last_recv was updated multiple times in parallel and the final sequence number was calculated with deltas which had no connection to the sequence number they were added to. Lock this whole region with the same lock which was already used to protect the unacked (out-of-order) list. Cc: stable@kernel.org Fixes: 33a3bb4a3345 ("batman-adv: throughput meter implementation") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: tp_meter: annotate last_recv_time access with READ/WRITE_ONCESven Eckelmann1-4/+4
The last_recv_time field for batadv_tp_receiver tracks the jiffies value of the most recent activity and is used to detect timeouts. These accesses are not consistently protected by a lock, so READ_ONCE/WRITE_ONCE must be used to prevent data races caused by compiler optimizations. Cc: stable@kernel.org Fixes: 33a3bb4a3345 ("batman-adv: throughput meter implementation") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: tp_meter: restrict number of unacked list entriesSven Eckelmann2-1/+25
When the unacked_list is unbound, an attacker could send messages with small lengths and appropriated seqno + gaps to force the receiver to allocate more and more unacked_list entries. And the end either causing an out-of-memory situation or increase the management overhead for the (large) list that significant portions of CPU cycles are wasted in searching through the list. When limiting the list to a specific number, it is important to still correctly add a new entry to the list. But if the list became larger than the limit, the last entry of the list (with the highest seqno) must be dropped to still allow the earlier seqnos to finish and therefore to continue the process. Otherwise, the process might get stuck with too high seqnos which are not handled by batadv_tp_ack_unordered(). Cc: stable@kernel.org Fixes: 33a3bb4a3345 ("batman-adv: throughput meter implementation") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: v: prevent OGM aggregation on disabled hardifSven Eckelmann3-0/+19
When an interface gets disabled, the worker is correctly disabled by batadv_hardif_disable_interface() -> ... -> batadv_v_ogm_iface_disable(). In this process, the skb aggr_list is also freed. But batadv_v_ogm_send_meshif() can still queue new skbs (via batadv_v_ogm_queue_on_if()) to the aggr_list. This will only stop after all cores can no longer find the RCU protected list of hard interfaces. These queued skbs will never be freed or consumed by batadv_v_ogm_aggr_work. The batadv_v_ogm_iface_disable() function must block batadv_v_ogm_queue_on_if() to avoid leak of skbs. Cc: stable@kernel.org Fixes: f89255a02f1d ("batman-adv: BATMAN_V: introduce per hard-iface OGMv2 queues") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: frag: avoid underflow of TTLSven Eckelmann1-0/+7
Packets with a TTL are using it to limit the amount of time this packet can be forwarded. But for batadv_frag_packet, the TTL was always only reduced but it was never evaluated. It could even underflow without any effect. Check the TTL in batadv_frag_skb_fwd() before attempting to prepare it for forwarding. This keeps it in sync with the not fragmented unicast packet. Cc: stable@kernel.org Fixes: 610bfc6bc99b ("batman-adv: Receive fragmented packets and merge") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: frag: ensure fragment is writable before modifying TTLSven Eckelmann3-4/+17
Before batman-adv is allowed to write to an skb, it either has to have its own copy of the skb or use skb_cow() to ensure that the data part is not shared. But batadv_frag_skb_fwd() modifies the TTL even when it is shared. Adding a skb_cow() right before this operation avoids this and can at the same time prepare it for the modifications required to forward the fragment. Cc: stable@kernel.org Fixes: 610bfc6bc99b ("batman-adv: Receive fragmented packets and merge") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: fix (m|b)cast csum after decrementing TTLSven Eckelmann1-2/+56
The broadcast and multicast packets can be received at the same time by the local system and forwarded to other nodes. Both are simply decrementing the TTL at the beginning of the receive path - independent of chosen paths (receive/forward). But such a modification of the data conflicts with the hw csum. This is not a problem when the packet is directly forwarded but can cause errors in the local receive path. Such a problem can then trigger a "hw csum failure". The receiver path must therefore ensure that the csum is fixed for each modification of the payload before batadv_interface_rx() is reached. Since all batman-adv packet types with a ttl have it as u8 at offset 2, a helper can be used for all of them. But it is only used at the moment for batadv_bcast_packet and batadv_mcast_packet because they are the only ones which deliver the packet locally but unconditionally modify the TTL. Cc: stable@kernel.org Fixes: 3f69339068f9 ("batman-adv: bcast: queue per interface, if needed") Fixes: 07afe1ba288c ("batman-adv: mcast: implement multicast packet reception and forwarding") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: ensure bcast is writable before modifying TTLSven Eckelmann1-0/+6
Before batman-adv is allowed to write to an skb, it either has to have its own copy of the skb or used skb_cow() to ensure that the data part is not shared. The old implementation used a shared queue and created copies before attempting to write to it. But with the new implementation, the broadcast packet is already modified when it gets received. Potentially writing to shared buffers in this process. Adding a skb_cow() right before this operation avoids this and can at the same time prepare it for the modifications required to rebroadcast the packet. Cc: stable@kernel.org Fixes: 3f69339068f9 ("batman-adv: bcast: queue per interface, if needed") Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-13batman-adv: gw: don't deselect gateway with active hardifSven Eckelmann1-26/+2
The batadv_hardif_cnt() was previously checking if there is an batadv_hard_iface->mesh_iface which is has the same mesh_iface. And since batadv_hardif_disable_interface() was resetting the batadv_hard_iface->mesh_iface after this check, it had to verify whether *1* interface was still part of the mesh_iface before it started the gateway deselection. But after batadv_hardif_cnt() is now checking the lower interfaces of mesh_iface and batadv_hardif_disable_interface() already removed the interface via netdev_upper_dev_unlink() earlier in this function, the check must now make sure that *0* interfaces can be found by batadv_hardif_cnt() before selected gateway must be deselected. Otherwise the deselection would already happen one batadv_hard_iface too early. Because a 0 hardif count from batadv_hardif_cnt() is equal to an empty list, it is possible to replace the counting with a simple list_empty(). Cc: stable@kernel.org Fixes: 7dc284702bcd ("batman-adv: store hard_iface as iflink private data") Reviewed-by: Nora Schiffer <neocturne@universe-factory.net> Signed-off-by: Sven Eckelmann <sven@narfation.org>
2026-06-12net: qrtr: fix 32-bit integer overflow in qrtr_endpoint_post()Michael Bommarito1-1/+1
qrtr_endpoint_post() validates an incoming packet with if (!size || len != ALIGN(size, 4) + hdrlen) goto err; where size comes from the wire. On 32-bit, size_t is 32 bits and ALIGN(size, 4) wraps to 0 for size >= 0xfffffffd, so the check passes and skb_put_data(skb, data + hdrlen, size) writes past the hdrlen-sized skb and oopses the kernel. 64-bit is unaffected. This is the 32-bit residual of ad9d24c9429e2 ("net: qrtr: fix OOB Read in qrtr_endpoint_post"), which fixed only the 64-bit case. Reject any size that cannot fit the buffer before the ALIGN. Fixes: ad9d24c9429e2 ("net: qrtr: fix OOB Read in qrtr_endpoint_post") Cc: stable@vger.kernel.org Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260611125455.2352279-1-michael.bommarito@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12psp: add a new netdev event for dev unregisterWei Wang5-1/+109
Add a new netdev event for dev unregister and handle the removal of this dev from psp->assoc_dev_list, upon the first dev-assoc operation. Signed-off-by: Wei Wang <weibunny@fb.com> Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com> Link: https://patch.msgid.link/20260608233118.2694144-4-weibunny.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12psp: add new netlink cmd for dev-assoc and dev-disassocWei Wang5-10/+365
The main purpose of this cmd is to be able to associate a non-psp-capable device (e.g. veth or netkit) with a psp device. One use case is if we create a pair of veth/netkit, and assign 1 end inside a netns, while leaving the other end within the default netns, with a real PSP device, e.g. netdevsim or a physical PSP-capable NIC. With this command, we could associate the veth/netkit inside the netns with PSP device, so the virtual device could act as PSP-capable device to initiate PSP connections, and performs PSP encryption/decryption on the real PSP device. Signed-off-by: Wei Wang <weibunny@fb.com> Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com> Link: https://patch.msgid.link/20260608233118.2694144-3-weibunny.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12psp: add admin/non-admin version of psp_device_get_lockedWei Wang5-13/+35
Introduce 2 versions of psp_device_get_locked: 1. psp_device_get_locked_admin(): This version is used for operations that would change the status of the psd, and are currently used for dev-set and key-rotation. 2. psp_device_get_locked(): This is the non-admin version, which are used for broader user issued operations including: dev-get, rx-assoc, tx-assoc, get-stats. Following commit will be implementing both of the checks. Signed-off-by: Wei Wang <weibunny@fb.com> Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com> Link: https://patch.msgid.link/20260608233118.2694144-2-weibunny.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net: bridge: use atomic ops to read/change p->flags (III)Eric Dumazet6-11/+12
Use test_bit(), clear_bit(), set_bit() in: net/bridge/br_multicast.c net/bridge/br_netlink.c net/bridge/br_stp.c net/bridge/br_stp_bpdu.c net/bridge/br_switchdev.c net/bridge/br_vlan_options.c Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260611203453.3067462-6-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net: bridge: use atomic ops to read/change p->flags (II)Eric Dumazet4-21/+21
Use READ_ONCE(p->flags) in br_port_flag_is_set() to keep its ABI. Use test_bit(), clear_bit(), set_bit() in: net/bridge/br_input.c net/bridge/br_mrp.c net/bridge/br_mrp_netlink.c Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260611203453.3067462-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net: bridge: use atomic ops to read/change p->flags (I)Eric Dumazet3-23/+16
Use test_bit() in net/bridge/br_arp_nd_proxy.c, net/bridge/br_fdb.c and net/bridge/br_forward.c. Use READ_ONCE(p->flags) in br_recalculate_neigh_suppress_enabled() as we test two bits at once. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260611203453.3067462-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12bridge: use atomic ops to read/change p->flags in br_netlink.cEric Dumazet1-40/+51
Change net/bridge/br_netlink.c to use atomic operations to read/change bits in p->flags. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260611203453.3067462-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12bridge: use atomic ops to read/change p->flags in sysfsEric Dumazet1-28/+32
Change net/bridge/br_sysfs_if.c to use atomic operations to read/change bits in p->flags. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260611203453.3067462-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net/sched: sch_dualpi2: Add missing module aliasVictor Nogueira1-0/+1
When a qdisc is added by name, the kernel tries to autoload its module via request_qdisc_module(), which calls: request_module(NET_SCH_ALIAS_PREFIX "%s", name); i.e. it asks modprobe to resolve the "net-sch-<kind>" alias (e.g. "net-sch-dualpi2") rather than the module's file name. Since dualpi2 was shipped without this alias, the autoload fails: tc qdisc add dev lo root handle 1: dualpi2 Error: Specified qdisc kind is unknown. Fix this by adding the missing alias so the qdisc is autoloaded on demand like the others. Fixes: 320d031ad6e4 ("sched: Struct definition and parsing of dualpi2 qdisc") Signed-off-by: Victor Nogueira <victor@mojatatu.com> Reviewed-by: Pedro Tammela <pctammela@mojatatu.com> Link: https://patch.msgid.link/20260611205849.3287640-1-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12ipv6: Honor oif when choosing nexthop for locally generated trafficIdo Schimmel1-1/+4
Commit 741a11d9e410 ("net: ipv6: Add RT6_LOOKUP_F_IFACE flag if oif is set") made the kernel honor the oif parameter when specified as part of output route lookup: # ip route add 2001:db8:1::/64 dev dummy1 # ip route add ::/0 dev dummy2 # ip route get 2001:db8:1::1 oif dummy2 fibmatch default dev dummy2 metric 1024 pref medium Due to regression reports, the behavior was partially reverted in commit d46a9d678e4c ("net: ipv6: Dont add RT6_LOOKUP_F_IFACE flag if saddr set") to only honor the oif if source address is not specified: # ip route get 2001:db8:1::1 from 2001:db8:2::1 oif dummy2 fibmatch 2001:db8:1::/64 dev dummy1 metric 1024 pref medium That is, when source address is specified, the kernel will choose the most specific route even if its nexthop device does not match the specified oif. This creates a problem for multipath routes. After looking up a route, when source address is not specified, the kernel will choose a nexthop whose nexthop device matches the specified oif: # sysctl -wq net.ipv6.conf.all.forwarding=1 # ip route add 2001:db8:10::/64 nexthop via fe80::1 dev dummy1 nexthop via fe80::2 dev dummy2 # for i in {1..100}; do ip route get 2001:db8:10::${i} oif dummy2; done | grep -o dummy[0-9] | sort | uniq -c 100 dummy2 But will disregard the oif when source address is specified despite the fact that a matching nexthop exists: # for i in {1..100}; do ip route get 2001:db8:10::${i} from 2001:db8:2::1 oif dummy2; done | grep -o dummy[0-9] | sort | uniq -c 53 dummy1 47 dummy2 This behavior differs from IPv4: # ip address add 192.0.2.1/32 dev lo # ip route add 198.51.100.0/24 nexthop via inet6 fe80::1 dev dummy1 nexthop via inet6 fe80::2 dev dummy2 # for i in {1..100}; do ip route get 198.51.100.${i} from 192.0.2.1 oif dummy2; done | grep -o dummy[0-9] | sort | uniq -c 100 dummy2 What happens is that fib6_table_lookup() returns a route with a matching nexthop device (assuming it exists): # perf record -e fib6:fib6_table_lookup -- bash -c "for i in {1..100}; do ip route get 2001:db8:10::${i} from 2001:db8:2::1 oif dummy2; done > /dev/null" # perf script | grep -o dummy[0-9] | sort | uniq -c 100 dummy2 But it is later overwritten during path selection in fib6_select_path() which instead chooses a nexthop according to the calculated hash. Solve this by telling fib6_select_path() to skip path selection if we have an oif match during output route lookup (iif being LOOPBACK_IFINDEX). Behavior after the change: # sysctl -wq net.ipv6.conf.all.forwarding=1 # ip route add 2001:db8:10::/64 nexthop via fe80::1 dev dummy1 nexthop via fe80::2 dev dummy2 # for i in {1..100}; do ip route get 2001:db8:10::${i} from 2001:db8:2::1 oif dummy2; done | grep -o dummy[0-9] | sort | uniq -c 100 dummy2 Note that enabling forwarding is only needed because we did not add neighbor entries for the gateway addresses. When forwarding is disabled and CONFIG_IPV6_ROUTER_PREF is not enabled in kernel config, the kernel will treat non-existing neighbor entries as errors and perform round-robin between the nexthops: # sysctl -wq net.ipv6.conf.all.forwarding=0 # for i in {1..100}; do ip route get 2001:db8:10::${i} from 2001:db8:2::1 oif dummy2; done | grep -o dummy[0-9] | sort | uniq -c 50 dummy1 50 dummy2 Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260611154605.992528-3-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12ipv6: Select best matching nexthop object in fib6_table_lookup()Ido Schimmel1-8/+9
Currently, when using multipath routes without nexthop objects, fib6_table_lookup() selects the nexthop with the highest score. This means that when both a source address and an oif are specified, the nexthop that is chosen is the one that matches in terms of oif: # sysctl -wq net.ipv6.conf.all.forwarding=1 # ip address add 2001:db8:2::1/64 dev lo # ip route add 2001:db8:10::/64 nexthop via fe80::1 dev dummy1 nexthop via fe80::2 dev dummy2 # perf record -e fib6:fib6_table_lookup -- bash -c "for i in {1..100}; do ip route get 2001:db8:10::${i} from 2001:db8:2::1 oif dummy1; done > /dev/null" # perf script | grep -o dummy[0-9] | sort | uniq -c 100 dummy1 # perf record -e fib6:fib6_table_lookup -- bash -c "for i in {1..100}; do ip route get 2001:db8:10::${i} from 2001:db8:2::1 oif dummy2; done > /dev/null" # perf script | grep -o dummy[0-9] | sort | uniq -c 100 dummy2 When using nexthop objects, fib6_table_lookup() selects the first matching nexthop and not necessarily the one with the highest score: # ip nexthop add id 1 via fe80::1 dev dummy1 # ip nexthop add id 2 via fe80::2 dev dummy2 # ip nexthop add id 3 group 1/2 # ip route add 2001:db8:20::/64 nhid 3 # perf record -e fib6:fib6_table_lookup -- bash -c "for i in {1..100}; do ip route get 2001:db8:20::${i} from 2001:db8:2::1 oif dummy1; done > /dev/null" # perf script | grep -o dummy[0-9] | sort | uniq -c 100 dummy1 # perf record -e fib6:fib6_table_lookup -- bash -c "for i in {1..100}; do ip route get 2001:db8:20::${i} from 2001:db8:2::1 oif dummy2; done > /dev/null" # perf script | grep -o dummy[0-9] | sort | uniq -c 100 dummy1 This is not very significant right now because the nexthop is later overwritten during path selection in fib6_select_path(). However, the next patch is going to skip path selection when we have an oif match during output route lookup. As a preparation for this change, align the nexthop object behavior with the legacy one and make sure that fib6_table_lookup() always selects the best matching nexthop. Do that by always returning 0 from rt6_nh_find_match() in order not to terminate the loop in nexthop_for_each_fib6_nh() and storing in arg->nh the best matching nexthop so far. Behavior after the change: # perf record -e fib6:fib6_table_lookup -- bash -c "for i in {1..100}; do ip route get 2001:db8:20::${i} from 2001:db8:2::1 oif dummy1; done > /dev/null" # perf script | grep -o dummy[0-9] | sort | uniq -c 100 dummy1 # perf record -e fib6:fib6_table_lookup -- bash -c "for i in {1..100}; do ip route get 2001:db8:20::${i} from 2001:db8:2::1 oif dummy2; done > /dev/null" # perf script | grep -o dummy[0-9] | sort | uniq -c 100 dummy2 Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20260611154605.992528-2-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net: watchdog: fix refcount tracking racesEric Dumazet2-12/+35
Blamed commit converted the untracked dev_hold()/dev_put() calls in the watchdog code to use the tracked dev_hold_track()/dev_put_track() (which were later renamed/interfaced to netdev_hold() and netdev_put()). By introducing dev->watchdog_dev_tracker to store the reference tracking information without adding synchronization between netdev_watchdog_up() and dev_watchdog(), it enabled the race condition where this pointer could be overwritten or freed concurrently, leading to the list corruption crash syzbot reported: list_del corruption, ffff888114a18c00->next is NULL kernel BUG at lib/list_debug.c:52 ! Oops: invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 1 UID: 0 PID: 91 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_unbound linkwatch_event RIP: 0010:__list_del_entry_valid_or_report.cold+0x22/0x2a lib/list_debug.c:52 Call Trace: <TASK> __list_del_entry_valid include/linux/list.h:132 [inline] __list_del_entry include/linux/list.h:246 [inline] list_move_tail include/linux/list.h:341 [inline] ref_tracker_free+0x1a7/0x6c0 lib/ref_tracker.c:329 netdev_tracker_free include/linux/netdevice.h:4491 [inline] netdev_put include/linux/netdevice.h:4508 [inline] netdev_put include/linux/netdevice.h:4504 [inline] netdev_watchdog_down net/sched/sch_generic.c:600 [inline] dev_deactivate_many+0x28c/0xfe0 net/sched/sch_generic.c:1363 dev_deactivate+0x109/0x1d0 net/sched/sch_generic.c:1397 linkwatch_do_dev net/core/link_watch.c:184 [inline] linkwatch_do_dev+0xd3/0x120 net/core/link_watch.c:166 __linkwatch_run_queue+0x3a5/0x810 net/core/link_watch.c:240 linkwatch_event+0x8f/0xc0 net/core/link_watch.c:314 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314 process_scheduled_works kernel/workqueue.c:3397 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 This patch has three coordinated parts: 1) Add dev->watchdog_lock and dev->watchdog_ref_held to serialize watchdog operations. 2) Remove netdev_watchdog_up() call from netif_carrier_on(): This ensures netdev_watchdog_up() is only called from process/BH context (via linkwatch workqueue dev_activate()), allowing us to use spin_lock_bh() for synchronization. 3) Synchronize watchdog up and watchdog timer: Protect netdev_watchdog_up() with tx_global_lock and watchdog_lock. Only allocate a new tracker in netdev_watchdog_up() if one is not already present. In dev_watchdog(), ensure we don't release the tracker if the timer was rescheduled either by dev_watchdog() itself or concurrently by netdev_watchdog_up(). Fixes: f12bf6f3f942 ("net: watchdog: add net device refcount tracker") Reported-by: syzbot+381d82bbf0253710b35d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a26b751.c25708ab.1b19ef.0013.GAE@google.com/T/#u Tested-by: syzbot+3479efbc2821cb2a79f2@syzkaller.appspotmail.com Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260611152737.2580480-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net/sched: sch_dualpi2: Do not call qdisc_tree_reduce_backlog during peek ↵Victor Nogueira1-2/+39
before restoring qlen Whenever dualpi2 drops packets during peek, it calls qdisc_tree_reduce_backlog. An issue arises because it calls qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops to zero, but peek returns an skb, the parent's qlen_notify callback will be executed even though dualpi2 still has 1 packet on the queue and, thus, mistakenly deactivates the parent's class which leads to a null-ptr-deref: [ 101.427314][ T599] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000009: 0000 [#1] SMP KASAN NOPTI [ 101.427755][ T599] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f] [ 101.428048][ T599] CPU: 2 UID: 0 PID: 599 Comm: ping Not tainted 7.1.0-rc5-00284-gbce53c430ed7 #102 PREEMPT(full) [ 101.428400][ T599] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 101.428608][ T599] RIP: 0010:qfq_dequeue (net/sched/sch_qfq.c:1150) sch_qfq [ 101.428821][ T599] Code: 00 fc ff df 80 3c 02 00 0f 85 46 0c 00 00 4c 8d 73 48 48 89 9d b8 02 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 2d 0c 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b All code [ 101.429348][ T599] RSP: 0018:ffff8881110df4f0 EFLAGS: 00010216 [ 101.429541][ T599] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: dffffc0000000000 [ 101.429763][ T599] RDX: 0000000000000009 RSI: 00000024c0000000 RDI: ffff88811436c2b0 [ 101.429985][ T599] RBP: ffff88811436c000 R08: ffff88811436c280 R09: 1ffff11021277523 [ 101.430206][ T599] R10: 1ffff11021277526 R11: 1ffff11021277527 R12: 00000024c0000000 [ 101.430423][ T599] R13: ffff88811436c2b8 R14: 0000000000000048 R15: 0000000020000000 [ 101.430642][ T599] FS: 00007f61813e1c40(0000) GS:ffff8881691ef000(0000) knlGS:0000000000000000 [ 101.430913][ T599] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 101.431100][ T599] CR2: 00005651650850a8 CR3: 000000010ca0b000 CR4: 0000000000750ef0 [ 101.431320][ T599] PKRU: 55555554 [ 101.431433][ T599] Call Trace: [ 101.431544][ T599] <TASK> [ 101.431628][ T599] __qdisc_run (net/sched/sch_generic.c:322 net/sched/sch_generic.c:427 net/sched/sch_generic.c:445) [ 101.431792][ T599] ? dev_qdisc_enqueue (./include/trace/events/qdisc.h:49 (discriminator 22) net/core/dev.c:4176 (discriminator 22)) [ 101.431941][ T599] __dev_queue_xmit (./include/net/pkt_sched.h:120 ./include/net/pkt_sched.h:117 net/core/dev.c:4292 net/core/dev.c:4831) Fix this by only calling qdisc_tree_reduce_backlog in peek after the qlen is restored. Fixes: 8f9516daedd6 ("sched: Add enqueue/dequeue of dualpi2 qdisc") Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260610192855.3121513-4-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net/sched: sch_codel: Do not call qdisc_tree_reduce_backlog during peek ↵Victor Nogueira1-5/+43
before restoring qlen Whenever codel drops packets during peek, it calls qdisc_tree_reduce_backlog. An issue arises because it calls qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops to zero, but peek returns an skb, the parent's qlen_notify callback will be executed even though codel still has 1 packet on the queue and, thus, will mistakenly deactivate the parent's class causing issues like a wild memory access when qfq has codel as a child: [ 36.339843][ T370] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI [ 36.340408][ T370] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127] [ 36.340737][ T370] CPU: 2 UID: 0 PID: 370 Comm: tc Not tainted 7.1.0-rc5-00287-g66e13b626592 #87 PREEMPT(full) [ 36.341113][ T370] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 36.341357][ T370] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq [ 36.342221][ T370] RSP: 0018:ffff8881100ef370 EFLAGS: 00010216 [ 36.342422][ T370] RAX: 0000000000000000 RBX: ffff8881058a9568 RCX: dffffc0000000000 [ 36.342664][ T370] RDX: 1ffff11021064dc3 RSI: ffff888108326e00 RDI: dffffc0000000000 [ 36.342905][ T370] RBP: ffff8881058a8280 R08: dead000000000122 R09: 1bd5a00000000024 [ 36.343140][ T370] R10: fffffbfff2940329 R11: fffffbfff2940329 R12: 0000000000000000 [ 36.343383][ T370] R13: dead000000000100 R14: ffff8881058a9580 R15: ffff8881058a9578 [ 36.343631][ T370] FS: 00007fc04b0ca780(0000) GS:ffff888184fef000(0000) knlGS:0000000000000000 [ 36.343911][ T370] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 36.344116][ T370] CR2: 0000557c02c02000 CR3: 000000010e0ba000 CR4: 0000000000750ef0 [ 36.344359][ T370] PKRU: 55555554 [ 36.344481][ T370] Call Trace: ... [ 36.345054][ T370] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1487) sch_qfq [ 36.345222][ T370] qdisc_reset (net/sched/sch_generic.c:1057) [ 36.345503][ T370] __qdisc_destroy (net/sched/sch_generic.c:1096) [ 36.345677][ T370] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159) [ 36.346335][ T370] tc_get_qdisc (net/sched/sch_api.c:1528 net/sched/sch_api.c:1556) Fix this by only calling qdisc_tree_reduce_backlog in peek after the qlen is restored. Fixes: 342debc12183 ("codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog()") Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260610192855.3121513-3-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12net/sched: sch_fq_codel: Do not call qdisc_tree_reduce_backlog during peek ↵Victor Nogueira1-2/+39
before restoring qlen Whenever fq_codel drops packets during peek, it calls qdisc_tree_reduce_backlog. An issue arises because it calls qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops to zero, but peek returns an skb, the parent's qlen_notify callback will be executed even though fq_codel still has 1 packet on the queue and, thus, will mistakenly deactivate the parent's class causing issues like a recent report [1] and a wild memory access in qfq: [ 29.371146][ T360] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI [ 29.371666][ T360] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127] [ 29.371987][ T360] CPU: 6 UID: 0 PID: 360 Comm: tc Not tainted 7.1.0-rc5-00285-gc530e5b2dbc6-dirty #82 PREEMPT(full) [ 29.372384][ T360] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 29.372620][ T360] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq [ 29.373544][ T360] RSP: 0018:ffff888102417370 EFLAGS: 00010216 [ 29.373800][ T360] RAX: 0000000000000000 RBX: ffff88811224d568 RCX: dffffc0000000000 [ 29.374079][ T360] RDX: 1ffff11021fe1543 RSI: ffff88810ff0aa00 RDI: dffffc0000000000 [ 29.374368][ T360] RBP: ffff88811224c280 R08: dead000000000122 R09: 1bd5a00000000024 [ 29.374649][ T360] R10: fffffbfff7940329 R11: fffffbfff7940329 R12: 0000000000000000 [ 29.374926][ T360] R13: dead000000000100 R14: ffff88811224d580 R15: ffff88811224d578 [ 29.375207][ T360] FS: 00007f5b794e5780(0000) GS:ffff88815d1e9000(0000) knlGS:0000000000000000 [ 29.375545][ T360] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 29.375823][ T360] CR2: 000055ffb091f000 CR3: 000000010a305000 CR4: 0000000000750ef0 [ 29.376103][ T360] PKRU: 55555554 [ 29.376258][ T360] Call Trace: [ 29.376401][ T360] <TASK> ... [ 29.376885][ T360] qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1487) sch_qfq [ 29.377074][ T360] qdisc_reset (net/sched/sch_generic.c:1057) [ 29.377414][ T360] __qdisc_destroy (net/sched/sch_generic.c:1096) [ 29.377600][ T360] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159) [ 29.378593][ T360] tc_get_qdisc (net/sched/sch_api.c:1528 net/sched/sch_api.c:1556) Fix this by only calling qdisc_tree_reduce_backlog in peek after the qlen is restored. [1] http://lore.kernel.org/netdev/CAN2cbVe79oj0O9==m4+4x3v+O+qzRagA=2=wkrp9i9=CqYvyZA@mail.gmail.com/ Fixes: 342debc12183 ("codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog()") Reported-by: Anirudh Gupta <anirudhrudr@gmail.com> Closes: https://lore.kernel.org/netdev/CAN2cbVe79oj0O9==m4+4x3v+O+qzRagA=2=wkrp9i9=CqYvyZA@mail.gmail.com/ Tested-by: Anirudh Gupta <anirudhrudr@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260610192855.3121513-2-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12ipv6: mcast: annotate igmp6 timer expiry raceYuyang Huang1-1/+2
/proc/net/igmp6 walks IPv6 multicast memberships under RCU and reads mca_work.timer.expires to print the remaining multicast timer. The delayed-work timer can be updated concurrently. Annotate the intentional lockless procfs snapshot with READ_ONCE(). Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260609081113.7613-3-sigefriedhyy@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-12ipv6: mcast: annotate data-races around mca_flagsYuyang Huang1-20/+32
/proc/net/igmp6 walks IPv6 multicast memberships under RCU and prints mca_flags without holding idev->mc_lock. The multicast paths update the field while holding idev->mc_lock. Annotate this intentional lockless snapshot with READ_ONCE() and the matching writers with WRITE_ONCE(). Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260609081113.7613-2-sigefriedhyy@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>