summaryrefslogtreecommitdiff
path: root/net/ipv4
AgeCommit message (Collapse)AuthorFilesLines
3 daysarp: do not assume dev_hard_header() does not change skb->headEric Dumazet1-3/+4
[ Upstream commit c92510f5e3f82ba11c95991824a41e59a9c5ed81 ] arp_create() is the only dev_hard_header() caller making assumption about skb->head being unchanged. A recent commit broke this assumption. Initialize @arp pointer after dev_hard_header() call. Fixes: db5b4e39c4e6 ("ip6_gre: make ip6gre_header() robust") Reported-by: syzbot+58b44a770a1585795351@syzkaller.appspotmail.com Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260107212250.384552-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
3 daysudp: call skb_orphan() before skb_attempt_defer_free()Eric Dumazet1-0/+1
[ Upstream commit e5c8eda39a9fc1547d1398d707aa06c1d080abdd ] Standard UDP receive path does not use skb->destructor. But skmsg layer does use it, since it calls skb_set_owner_sk_safe() from udp_read_skb(). This then triggers this warning in skb_attempt_defer_free(): DEBUG_NET_WARN_ON_ONCE(skb->destructor); We must call skb_orphan() to fix this issue. Fixes: 6471658dc66c ("udp: use skb_attempt_defer_free()") Reported-by: syzbot+3e68572cf2286ce5ebe9@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/695b83bd.050a0220.1c9965.002b.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260105093630.1976085-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
3 daysinet: frags: drop fraglist conntrack referencesFlorian Westphal1-0/+2
[ Upstream commit 2ef02ac38d3c17f34a00c4b267d961a8d4b45d1a ] Jakub added a warning in nf_conntrack_cleanup_net_list() to make debugging leaked skbs/conntrack references more obvious. syzbot reports this as triggering, and I can also reproduce this via ip_defrag.sh selftest: conntrack cleanup blocked for 60s WARNING: net/netfilter/nf_conntrack_core.c:2512 [..] conntrack clenups gets stuck because there are skbs with still hold nf_conn references via their frag_list. net.core.skb_defer_max=0 makes the hang disappear. Eric Dumazet points out that skb_release_head_state() doesn't follow the fraglist. ip_defrag.sh can only reproduce this problem since commit 6471658dc66c ("udp: use skb_attempt_defer_free()"), but AFAICS this problem could happen with TCP as well if pmtu discovery is off. The relevant problem path for udp is: 1. netns emits fragmented packets 2. nf_defrag_v6_hook reassembles them (in output hook) 3. reassembled skb is tracked (skb owns nf_conn reference) 4. ip6_output refragments 5. refragmented packets also own nf_conn reference (ip6_fragment calls ip6_copy_metadata()) 6. on input path, nf_defrag_v6_hook skips defragmentation: the fragments already have skb->nf_conn attached 7. skbs are reassembled via ipv6_frag_rcv() 8. skb_consume_udp -> skb_attempt_defer_free() -> skb ends up in pcpu freelist, but still has nf_conn reference. Possible solutions: 1 let defrag engine drop nf_conn entry, OR 2 export kick_defer_list_purge() and call it from the conntrack netns exit callback, OR 3 add skb_has_frag_list() check to skb_attempt_defer_free() 2 & 3 also solve ip_defrag.sh hang but share same drawback: Such reassembled skbs, queued to socket, can prevent conntrack module removal until userspace has consumed the packet. While both tcp and udp stack do call nf_reset_ct() before placing skb on socket queue, that function doesn't iterate frag_list skbs. Therefore drop nf_conn entries when they are placed in defrag queue. Keep the nf_conn entry of the first (offset 0) skb so that reassembled skb retains nf_conn entry for sake of TX path. Note that fixes tag is incorrect; it points to the commit introducing the 'ip_defrag.sh reproducible problem': no need to backport this patch to every stable kernel. Reported-by: syzbot+4393c47753b7808dac7d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/693b0fa7.050a0220.4004e.040d.GAE@google.com/ Fixes: 6471658dc66c ("udp: use skb_attempt_defer_free()") Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260102140030.32367-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
3 daysinet: ping: Fix icmp out countingyuan.gao1-3/+1
[ Upstream commit 4c0856c225b39b1def6c9a6bc56faca79550da13 ] When the ping program uses an IPPROTO_ICMP socket to send ICMP_ECHO messages, ICMP_MIB_OUTMSGS is counted twice. ping_v4_sendmsg ping_v4_push_pending_frames ip_push_pending_frames ip_finish_skb __ip_make_skb icmp_out_count(net, icmp_type); // first count icmp_out_count(sock_net(sk), user_icmph.type); // second count However, when the ping program uses an IPPROTO_RAW socket, ICMP_MIB_OUTMSGS is counted correctly only once. Therefore, the first count should be removed. Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Signed-off-by: yuan.gao <yuan.gao@ucloud.cn> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20251224063145.3615282-1-yuan.gao@ucloud.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
3 daysnet: do not write to msg_get_inq in calleeWillem de Bruijn1-5/+3
commit 7d11e047eda5f98514ae62507065ac961981c025 upstream. NULL pointer dereference fix. msg_get_inq is an input field from caller to callee. Don't set it in the callee, as the caller may not clear it on struct reuse. This is a kernel-internal variant of msghdr only, and the only user does reinitialize the field. So this is not critical for that reason. But it is more robust to avoid the write, and slightly simpler code. And it fixes a bug, see below. Callers set msg_get_inq to request the input queue length to be returned in msg_inq. This is equivalent to but independent from the SO_INQ request to return that same info as a cmsg (tp->recvmsg_inq). To reduce branching in the hot path the second also sets the msg_inq. That is WAI. This is a fix to commit 4d1442979e4a ("af_unix: don't post cmsg for SO_INQ unless explicitly asked for"), which fixed the inverse. Also avoid NULL pointer dereference in unix_stream_read_generic if state->msg is NULL and msg->msg_get_inq is written. A NULL state->msg can happen when splicing as of commit 2b514574f7e8 ("net: af_unix: implement splice for stream af_unix sockets"). Also collapse two branches using a bitwise or. Cc: stable@vger.kernel.org Fixes: 4d1442979e4a ("af_unix: don't post cmsg for SO_INQ unless explicitly asked for") Link: https://lore.kernel.org/netdev/willemdebruijn.kernel.24d8030f7a3de@gmail.com/ Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260106150626.3944363-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
12 dayserspan: Initialize options_len before referencing options.Frode Nordahl1-2/+4
commit 35ddf66c65eff93fff91406756ba273600bf61a3 upstream. The struct ip_tunnel_info has a flexible array member named options that is protected by a counted_by(options_len) attribute. The compiler will use this information to enforce runtime bounds checking deployed by FORTIFY_SOURCE string helpers. As laid out in the GCC documentation, the counter must be initialized before the first reference to the flexible array member. After scanning through the files that use struct ip_tunnel_info and also refer to options or options_len, it appears the normal case is to use the ip_tunnel_info_opts_set() helper. Said helper would initialize options_len properly before copying data into options, however in the GRE ERSPAN code a partial update is done, preventing the use of the helper function. Before this change the handling of ERSPAN traffic in GRE tunnels would cause a kernel panic when the kernel is compiled with GCC 15+ and having FORTIFY_SOURCE configured: memcpy: detected buffer overflow: 4 byte write of buffer size 0 Call Trace: <IRQ> __fortify_panic+0xd/0xf erspan_rcv.cold+0x68/0x83 ? ip_route_input_slow+0x816/0x9d0 gre_rcv+0x1b2/0x1c0 gre_rcv+0x8e/0x100 ? raw_v4_input+0x2a0/0x2b0 ip_protocol_deliver_rcu+0x1ea/0x210 ip_local_deliver_finish+0x86/0x110 ip_local_deliver+0x65/0x110 ? ip_rcv_finish_core+0xd6/0x360 ip_rcv+0x186/0x1a0 Cc: stable@vger.kernel.org Link: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-counted_005fby-variable-attribute Reported-at: https://launchpad.net/bugs/2129580 Fixes: bb5e62f2d547 ("net: Add options as a flexible array to struct ip_tunnel_info") Signed-off-by: Frode Nordahl <fnordahl@ubuntu.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20251213101338.4693-1-fnordahl@ubuntu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
12 daysnet: fib: restore ECMP balance from loopbackVadim Fedorenko1-16/+10
[ Upstream commit 6e17474aa9fe15015c9921a5081c7ca71783aac6 ] Preference of nexthop with source address broke ECMP for packets with source addresses which are not in the broadcast domain, but rather added to loopback/dummy interfaces. Original behaviour was to balance over nexthops while now it uses the latest nexthop from the group. To fix the issue introduce next hop scoring system where next hops with source address equal to requested will always have higher priority. For the case with 198.51.100.1/32 assigned to dummy0 and routed using 192.0.2.0/24 and 203.0.113.0/24 networks: 2: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether d6:54:8a:ff:78:f5 brd ff:ff:ff:ff:ff:ff inet 198.51.100.1/32 scope global dummy0 valid_lft forever preferred_lft forever 7: veth1@if6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 06:ed:98:87:6d:8a brd ff:ff:ff:ff:ff:ff link-netnsid 0 inet 192.0.2.2/24 scope global veth1 valid_lft forever preferred_lft forever inet6 fe80::4ed:98ff:fe87:6d8a/64 scope link proto kernel_ll valid_lft forever preferred_lft forever 9: veth3@if8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether ae:75:23:38:a0:d2 brd ff:ff:ff:ff:ff:ff link-netnsid 0 inet 203.0.113.2/24 scope global veth3 valid_lft forever preferred_lft forever inet6 fe80::ac75:23ff:fe38:a0d2/64 scope link proto kernel_ll valid_lft forever preferred_lft forever ~ ip ro list: default nexthop via 192.0.2.1 dev veth1 weight 1 nexthop via 203.0.113.1 dev veth3 weight 1 192.0.2.0/24 dev veth1 proto kernel scope link src 192.0.2.2 203.0.113.0/24 dev veth3 proto kernel scope link src 203.0.113.2 before: for i in {1..255} ; do ip ro get 10.0.0.$i; done | grep veth | awk ' {print $(NF-2)}' | sort | uniq -c: 255 veth3 after: for i in {1..255} ; do ip ro get 10.0.0.$i; done | grep veth | awk ' {print $(NF-2)}' | sort | uniq -c: 122 veth1 133 veth3 Fixes: 32607a332cfe ("ipv4: prefer multipath nexthop that matches source address") Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20251221192639.3911901-1-vadim.fedorenko@linux.dev Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
12 daysipv4: Fix reference count leak when using error routes with nexthop objectsIdo Schimmel1-3/+4
[ Upstream commit ac782f4e3bfcde145b8a7f8af31d9422d94d172a ] When a nexthop object is deleted, it is marked as dead and then fib_table_flush() is called to flush all the routes that are using the dead nexthop. The current logic in fib_table_flush() is to only flush error routes (e.g., blackhole) when it is called as part of network namespace dismantle (i.e., with flush_all=true). Therefore, error routes are not flushed when their nexthop object is deleted: # ip link add name dummy1 up type dummy # ip nexthop add id 1 dev dummy1 # ip route add 198.51.100.1/32 nhid 1 # ip route add blackhole 198.51.100.2/32 nhid 1 # ip nexthop del id 1 # ip route show blackhole 198.51.100.2 nhid 1 dev dummy1 As such, they keep holding a reference on the nexthop object which in turn holds a reference on the nexthop device, resulting in a reference count leak: # ip link del dev dummy1 [ 70.516258] unregister_netdevice: waiting for dummy1 to become free. Usage count = 2 Fix by flushing error routes when their nexthop is marked as dead. IPv6 does not suffer from this problem. Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Closes: https://lore.kernel.org/netdev/d943f806-4da6-4970-ac28-b9373b0e63ac@I-love.SAKURA.ne.jp/ Reported-by: syzbot+881d65229ca4f9ae8c84@syzkaller.appspotmail.com Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20251221144829.197694-1-idosch@nvidia.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-02inet: frags: flush pending skbs in fqdir_pre_exit()Jakub Kicinski2-5/+43
[ Upstream commit 006a5035b495dec008805df249f92c22c89c3d2e ] We have been seeing occasional deadlocks on pernet_ops_rwsem since September in NIPA. The stuck task was usually modprobe (often loading a driver like ipvlan), trying to take the lock as a Writer. lockdep does not track readers for rwsems so the read wasn't obvious from the reports. On closer inspection the Reader holding the lock was conntrack looping forever in nf_conntrack_cleanup_net_list(). Based on past experience with occasional NIPA crashes I looked thru the tests which run before the crash and noticed that the crash follows ip_defrag.sh. An immediate red flag. Scouring thru (de)fragmentation queues reveals skbs sitting around, holding conntrack references. The problem is that since conntrack depends on nf_defrag_ipv6, nf_defrag_ipv6 will load first. Since nf_defrag_ipv6 loads first its netns exit hooks run _after_ conntrack's netns exit hook. Flush all fragment queue SKBs during fqdir_pre_exit() to release conntrack references before conntrack cleanup runs. Also flush the queues in timer expiry handlers when they discover fqdir->dead is set, in case packet sneaks in while we're running the pre_exit flush. The commit under Fixes is not exactly the culprit, but I think previously the timer firing would eventually unblock the spinning conntrack. Fixes: d5dd88794a13 ("inet: fix various use-after-free in defrags units") Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20251207010942.1672972-4-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-02inet: frags: add inet_frag_queue_flush()Jakub Kicinski2-8/+13
[ Upstream commit 1231eec6994be29d6bb5c303dfa54731ed9fc0e6 ] Instead of exporting inet_frag_rbtree_purge() which requires that caller takes care of memory accounting, add a new helper. We will need to call it from a few places in the next patch. Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20251207010942.1672972-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Stable-dep-of: 006a5035b495 ("inet: frags: flush pending skbs in fqdir_pre_exit()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-02inet: frags: avoid theoretical race in ip_frag_reinit()Jakub Kicinski2-4/+4
[ Upstream commit 8ef522c8a59a048117f7e05eb5213043c02f986f ] In ip_frag_reinit() we want to move the frag timeout timer into the future. If the timer fires in the meantime we inadvertently scheduled it again, and since the timer assumes a ref on frag_queue we need to acquire one to balance things out. This is technically racy, we should have acquired the reference _before_ we touch the timer, it may fire again before we take the ref. Avoid this entire dance by using mod_timer_pending() which only modifies the timer if its pending (and which exists since Linux v2.6.30) Note that this was the only place we ever took a ref on frag_queue since Eric's conversion to RCU. So we could potentially replace the whole refcnt field with an atomic flag and a bit more RCU. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20251207010942.1672972-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-19Merge tag 'ipsec-2025-11-18' of ↵Jakub Kicinski1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2025-11-18 1) Misc fixes for xfrm_state creation/modification/deletion. Patchset from Sabrina Dubroca. 2) Fix inner packet family determination for xfrm offloads. From Jianbo Liu. 3) Don't push locally generated packets directly to L2 tunnel mode offloading, they still need processing from the standard xfrm path. From Jianbo Liu. 4) Fix memory leaks in xfrm_add_acquire for policy offloads and policy security contexts. From Zilin Guan. * tag 'ipsec-2025-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec: xfrm: fix memory leak in xfrm_add_acquire() xfrm: Prevent locally generated packets from direct output in tunnel mode xfrm: Determine inner GSO type from packet inner protocol xfrm: Check inner packet family directly from skb_dst xfrm: check all hash buckets for leftover states during netns deletion xfrm: set err and extack on failure to create pcpu SA xfrm: call xfrm_dev_state_delete when xfrm_state_migrate fails to add the state xfrm: make state as DEAD before final put when migrate fails xfrm: also call xfrm_state_delete_tunnel at destroy time for states that were never added xfrm: drop SA reference in xfrm_state_update if dir doesn't match ==================== Link: https://patch.msgid.link/20251118085344.2199815-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-11-12ipv4: route: Prevent rt_bind_exception() from rebinding stale fnheChuang Wang1-0/+5
The sit driver's packet transmission path calls: sit_tunnel_xmit() -> update_or_create_fnhe(), which lead to fnhe_remove_oldest() being called to delete entries exceeding FNHE_RECLAIM_DEPTH+random. The race window is between fnhe_remove_oldest() selecting fnheX for deletion and the subsequent kfree_rcu(). During this time, the concurrent path's __mkroute_output() -> find_exception() can fetch the soon-to-be-deleted fnheX, and rt_bind_exception() then binds it with a new dst using a dst_hold(). When the original fnheX is freed via RCU, the dst reference remains permanently leaked. CPU 0 CPU 1 __mkroute_output() find_exception() [fnheX] update_or_create_fnhe() fnhe_remove_oldest() [fnheX] rt_bind_exception() [bind dst] RCU callback [fnheX freed, dst leak] This issue manifests as a device reference count leak and a warning in dmesg when unregistering the net device: unregister_netdevice: waiting for sitX to become free. Usage count = N Ido Schimmel provided the simple test validation method [1]. The fix clears 'oldest->fnhe_daddr' before calling fnhe_flush_routes(). Since rt_bind_exception() checks this field, setting it to zero prevents the stale fnhe from being reused and bound to a new dst just before it is freed. [1] ip netns add ns1 ip -n ns1 link set dev lo up ip -n ns1 address add 192.0.2.1/32 dev lo ip -n ns1 link add name dummy1 up type dummy ip -n ns1 route add 192.0.2.2/32 dev dummy1 ip -n ns1 link add name gretap1 up arp off type gretap \ local 192.0.2.1 remote 192.0.2.2 ip -n ns1 route add 198.51.0.0/16 dev gretap1 taskset -c 0 ip netns exec ns1 mausezahn gretap1 \ -A 198.51.100.1 -B 198.51.0.0/16 -t udp -p 1000 -c 0 -q & taskset -c 2 ip netns exec ns1 mausezahn gretap1 \ -A 198.51.100.1 -B 198.51.0.0/16 -t udp -p 1000 -c 0 -q & sleep 10 ip netns pids ns1 | xargs kill ip netns del ns1 Cc: stable@vger.kernel.org Fixes: 67d6d681e15b ("ipv4: make exception cache less predictible") Signed-off-by: Chuang Wang <nashuiliang@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20251111064328.24440-1-nashuiliang@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-30xfrm: Determine inner GSO type from packet inner protocolJianbo Liu1-2/+4
The GSO segmentation functions for ESP tunnel mode (xfrm4_tunnel_gso_segment and xfrm6_tunnel_gso_segment) were determining the inner packet's L2 protocol type by checking the static x->inner_mode.family field from the xfrm state. This is unreliable. In tunnel mode, the state's actual inner family could be defined by x->inner_mode.family or by x->inner_mode_iaf.family. Checking only the former can lead to a mismatch with the actual packet being processed, causing GSO to create segments with the wrong L2 header type. This patch fixes the bug by deriving the inner mode directly from the packet's inner protocol stored in XFRM_MODE_SKB_CB(skb)->protocol. Instead of replicating the code, this patch modifies the xfrm_ip2inner_mode helper function. It now correctly returns &x->inner_mode if the selector family (x->sel.family) is already specified, thereby handling both specific and AF_UNSPEC cases appropriately. With this change, ESP GSO can use xfrm_ip2inner_mode to get the correct inner mode. It doesn't affect existing callers, as the updated logic now mirrors the checks they were already performing externally. Fixes: 26dbd66eab80 ("esp: choose the correct inner protocol for GSO on inter address family tunnels") Signed-off-by: Jianbo Liu <jianbol@nvidia.com> Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2025-10-30tcp: fix too slow tcp_rcvbuf_grow() actionEric Dumazet1-2/+9
While the blamed commits apparently avoided an overshoot, they also limited how fast a sender can increase BDP at each RTT. This is not exactly a revert, we do not add the 16 * tp->advmss cushion we had, and we are keeping the out_of_order_queue contribution. Do the same in mptcp_rcvbuf_grow(). Tested: emulated 50ms rtt (tcp_stream --tcp-tx-delay 50000), cubic 20 second flow. net.ipv4.tcp_rmem set to "4096 131072 67000000" perf record -a -e tcp:tcp_rcvbuf_grow sleep 20 perf script Before: We can see we fail to roughly double RWIN at each RTT. Sender is RWIN limited while CWND is ramping up (before getting tcp_wmem limited). tcp_stream 33793 [010] 825.717525: tcp:tcp_rcvbuf_grow: time=100869 rtt_us=50428 copied=49152 inq=0 space=40960 ooo=0 scaling_ratio=219 rcvbuf=131072 rcv_ssthresh=103970 window_clamp=112128 rcv_wnd=106496 tcp_stream 33793 [010] 825.768966: tcp:tcp_rcvbuf_grow: time=51447 rtt_us=50362 copied=86016 inq=0 space=49152 ooo=0 scaling_ratio=219 rcvbuf=131072 rcv_ssthresh=107474 window_clamp=112128 rcv_wnd=106496 tcp_stream 33793 [010] 825.821539: tcp:tcp_rcvbuf_grow: time=52577 rtt_us=50243 copied=114688 inq=0 space=86016 ooo=0 scaling_ratio=219 rcvbuf=201096 rcv_ssthresh=167377 window_clamp=172031 rcv_wnd=167936 tcp_stream 33793 [010] 825.871781: tcp:tcp_rcvbuf_grow: time=50248 rtt_us=50237 copied=167936 inq=0 space=114688 ooo=0 scaling_ratio=219 rcvbuf=268129 rcv_ssthresh=224722 window_clamp=229375 rcv_wnd=225280 tcp_stream 33793 [010] 825.922475: tcp:tcp_rcvbuf_grow: time=50698 rtt_us=50183 copied=241664 inq=0 space=167936 ooo=0 scaling_ratio=219 rcvbuf=392617 rcv_ssthresh=331217 window_clamp=335871 rcv_wnd=323584 tcp_stream 33793 [010] 825.973326: tcp:tcp_rcvbuf_grow: time=50855 rtt_us=50213 copied=339968 inq=0 space=241664 ooo=0 scaling_ratio=219 rcvbuf=564986 rcv_ssthresh=478674 window_clamp=483327 rcv_wnd=462848 tcp_stream 33793 [010] 826.023970: tcp:tcp_rcvbuf_grow: time=50647 rtt_us=50248 copied=491520 inq=0 space=339968 ooo=0 scaling_ratio=219 rcvbuf=794811 rcv_ssthresh=671778 window_clamp=679935 rcv_wnd=651264 tcp_stream 33793 [010] 826.074612: tcp:tcp_rcvbuf_grow: time=50648 rtt_us=50227 copied=700416 inq=0 space=491520 ooo=0 scaling_ratio=219 rcvbuf=1149124 rcv_ssthresh=974881 window_clamp=983039 rcv_wnd=942080 tcp_stream 33793 [010] 826.125452: tcp:tcp_rcvbuf_grow: time=50845 rtt_us=50225 copied=987136 inq=8192 space=700416 ooo=0 scaling_ratio=219 rcvbuf=1637502 rcv_ssthresh=1392674 window_clamp=1400831 rcv_wnd=1339392 tcp_stream 33793 [010] 826.175698: tcp:tcp_rcvbuf_grow: time=50250 rtt_us=50198 copied=1347584 inq=0 space=978944 ooo=0 scaling_ratio=219 rcvbuf=2288672 rcv_ssthresh=1949729 window_clamp=1957887 rcv_wnd=1945600 tcp_stream 33793 [010] 826.225947: tcp:tcp_rcvbuf_grow: time=50252 rtt_us=50240 copied=1945600 inq=0 space=1347584 ooo=0 scaling_ratio=219 rcvbuf=3150516 rcv_ssthresh=2687010 window_clamp=2695167 rcv_wnd=2691072 tcp_stream 33793 [010] 826.276175: tcp:tcp_rcvbuf_grow: time=50233 rtt_us=50224 copied=2691072 inq=0 space=1945600 ooo=0 scaling_ratio=219 rcvbuf=4548617 rcv_ssthresh=3883041 window_clamp=3891199 rcv_wnd=3887104 tcp_stream 33793 [010] 826.326403: tcp:tcp_rcvbuf_grow: time=50233 rtt_us=50229 copied=3887104 inq=0 space=2691072 ooo=0 scaling_ratio=219 rcvbuf=6291456 rcv_ssthresh=5370482 window_clamp=5382144 rcv_wnd=5373952 tcp_stream 33793 [010] 826.376723: tcp:tcp_rcvbuf_grow: time=50323 rtt_us=50218 copied=5373952 inq=0 space=3887104 ooo=0 scaling_ratio=219 rcvbuf=9087658 rcv_ssthresh=7755537 window_clamp=7774207 rcv_wnd=7757824 tcp_stream 33793 [010] 826.426991: tcp:tcp_rcvbuf_grow: time=50274 rtt_us=50196 copied=7757824 inq=180224 space=5373952 ooo=0 scaling_ratio=219 rcvbuf=12563759 rcv_ssthresh=10729233 window_clamp=10747903 rcv_wnd=10575872 tcp_stream 33793 [010] 826.477229: tcp:tcp_rcvbuf_grow: time=50241 rtt_us=50078 copied=10731520 inq=180224 space=7577600 ooo=0 scaling_ratio=219 rcvbuf=17715667 rcv_ssthresh=15136529 window_clamp=15155199 rcv_wnd=14983168 tcp_stream 33793 [010] 826.527482: tcp:tcp_rcvbuf_grow: time=50258 rtt_us=50153 copied=15138816 inq=360448 space=10551296 ooo=0 scaling_ratio=219 rcvbuf=24667870 rcv_ssthresh=21073410 window_clamp=21102591 rcv_wnd=20766720 tcp_stream 33793 [010] 826.577712: tcp:tcp_rcvbuf_grow: time=50234 rtt_us=50228 copied=21073920 inq=0 space=14778368 ooo=0 scaling_ratio=219 rcvbuf=34550339 rcv_ssthresh=29517041 window_clamp=29556735 rcv_wnd=29519872 tcp_stream 33793 [010] 826.627982: tcp:tcp_rcvbuf_grow: time=50275 rtt_us=50220 copied=29519872 inq=540672 space=21073920 ooo=0 scaling_ratio=219 rcvbuf=49268707 rcv_ssthresh=42090625 window_clamp=42147839 rcv_wnd=41627648 tcp_stream 33793 [010] 826.678274: tcp:tcp_rcvbuf_grow: time=50296 rtt_us=50185 copied=42053632 inq=761856 space=28979200 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57238168 window_clamp=57316406 rcv_wnd=56606720 tcp_stream 33793 [010] 826.728627: tcp:tcp_rcvbuf_grow: time=50357 rtt_us=50128 copied=43913216 inq=851968 space=41291776 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57290728 window_clamp=57316406 rcv_wnd=56524800 tcp_stream 33793 [010] 827.131364: tcp:tcp_rcvbuf_grow: time=50239 rtt_us=50127 copied=43843584 inq=655360 space=43061248 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57290728 window_clamp=57316406 rcv_wnd=56696832 tcp_stream 33793 [010] 827.181613: tcp:tcp_rcvbuf_grow: time=50254 rtt_us=50115 copied=43843584 inq=524288 space=43188224 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57290728 window_clamp=57316406 rcv_wnd=56807424 tcp_stream 33793 [010] 828.339635: tcp:tcp_rcvbuf_grow: time=50283 rtt_us=50110 copied=43843584 inq=458752 space=43319296 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57290728 window_clamp=57316406 rcv_wnd=56864768 tcp_stream 33793 [010] 828.440350: tcp:tcp_rcvbuf_grow: time=50404 rtt_us=50099 copied=43843584 inq=393216 space=43384832 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57290728 window_clamp=57316406 rcv_wnd=56922112 tcp_stream 33793 [010] 829.195106: tcp:tcp_rcvbuf_grow: time=50154 rtt_us=50077 copied=43843584 inq=196608 space=43450368 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57290728 window_clamp=57316406 rcv_wnd=57090048 After: It takes few steps to increase RWIN. Sender is no longer RWIN limited. tcp_stream 50826 [010] 935.634212: tcp:tcp_rcvbuf_grow: time=100788 rtt_us=50315 copied=49152 inq=0 space=40960 ooo=0 scaling_ratio=219 rcvbuf=131072 rcv_ssthresh=103970 window_clamp=112128 rcv_wnd=106496 tcp_stream 50826 [010] 935.685642: tcp:tcp_rcvbuf_grow: time=51437 rtt_us=50361 copied=86016 inq=0 space=49152 ooo=0 scaling_ratio=219 rcvbuf=160875 rcv_ssthresh=132969 window_clamp=137623 rcv_wnd=131072 tcp_stream 50826 [010] 935.738299: tcp:tcp_rcvbuf_grow: time=52660 rtt_us=50256 copied=139264 inq=0 space=86016 ooo=0 scaling_ratio=219 rcvbuf=502741 rcv_ssthresh=411497 window_clamp=430079 rcv_wnd=413696 tcp_stream 50826 [010] 935.788544: tcp:tcp_rcvbuf_grow: time=50249 rtt_us=50233 copied=307200 inq=0 space=139264 ooo=0 scaling_ratio=219 rcvbuf=728690 rcv_ssthresh=618717 window_clamp=623371 rcv_wnd=618496 tcp_stream 50826 [010] 935.838796: tcp:tcp_rcvbuf_grow: time=50258 rtt_us=50202 copied=618496 inq=0 space=307200 ooo=0 scaling_ratio=219 rcvbuf=2450338 rcv_ssthresh=1855709 window_clamp=2096187 rcv_wnd=1859584 tcp_stream 50826 [010] 935.889140: tcp:tcp_rcvbuf_grow: time=50347 rtt_us=50166 copied=1261568 inq=0 space=618496 ooo=0 scaling_ratio=219 rcvbuf=4376503 rcv_ssthresh=3725291 window_clamp=3743961 rcv_wnd=3706880 tcp_stream 50826 [010] 935.939435: tcp:tcp_rcvbuf_grow: time=50300 rtt_us=50185 copied=2478080 inq=24576 space=1261568 ooo=0 scaling_ratio=219 rcvbuf=9082648 rcv_ssthresh=7733731 window_clamp=7769921 rcv_wnd=7692288 tcp_stream 50826 [010] 935.989681: tcp:tcp_rcvbuf_grow: time=50251 rtt_us=50221 copied=4915200 inq=114688 space=2453504 ooo=0 scaling_ratio=219 rcvbuf=16574936 rcv_ssthresh=14108110 window_clamp=14179339 rcv_wnd=14024704 tcp_stream 50826 [010] 936.039967: tcp:tcp_rcvbuf_grow: time=50289 rtt_us=50279 copied=9830400 inq=114688 space=4800512 ooo=0 scaling_ratio=219 rcvbuf=32695050 rcv_ssthresh=27896187 window_clamp=27969593 rcv_wnd=27815936 tcp_stream 50826 [010] 936.090172: tcp:tcp_rcvbuf_grow: time=50211 rtt_us=50200 copied=19841024 inq=114688 space=9715712 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57245176 window_clamp=57316406 rcv_wnd=57163776 tcp_stream 50826 [010] 936.140430: tcp:tcp_rcvbuf_grow: time=50262 rtt_us=50197 copied=39501824 inq=114688 space=19726336 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57245176 window_clamp=57316406 rcv_wnd=57163776 tcp_stream 50826 [010] 936.190527: tcp:tcp_rcvbuf_grow: time=50101 rtt_us=50071 copied=43655168 inq=262144 space=39387136 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57259192 window_clamp=57316406 rcv_wnd=57032704 tcp_stream 50826 [010] 936.240719: tcp:tcp_rcvbuf_grow: time=50197 rtt_us=50057 copied=43843584 inq=262144 space=43393024 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57259192 window_clamp=57316406 rcv_wnd=57032704 tcp_stream 50826 [010] 936.341271: tcp:tcp_rcvbuf_grow: time=50297 rtt_us=50123 copied=43843584 inq=131072 space=43581440 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57259192 window_clamp=57316406 rcv_wnd=57147392 tcp_stream 50826 [010] 936.642503: tcp:tcp_rcvbuf_grow: time=50131 rtt_us=50084 copied=43843584 inq=0 space=43712512 ooo=0 scaling_ratio=219 rcvbuf=67000000 rcv_ssthresh=57259192 window_clamp=57316406 rcv_wnd=57262080 Fixes: 65c5287892e9 ("tcp: fix sk_rcvbuf overshoot") Fixes: e118cdc34dd1 ("mptcp: rcvbuf auto-tuning improvement") Reported-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/589 Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20251028-net-tcp-recv-autotune-v3-4-74b43ba4c84c@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-30tcp: add newval parameter to tcp_rcvbuf_grow()Eric Dumazet1-7/+7
This patch has no functional change, and prepares the following one. tcp_rcvbuf_grow() will need to have access to tp->rcvq_space.space old and new values. Change mptcp_rcvbuf_grow() in a similar way. Signed-off-by: Eric Dumazet <edumazet@google.com> [ Moved 'oldval' declaration to the next patch to avoid warnings at build time. ] Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20251028-net-tcp-recv-autotune-v3-3-74b43ba4c84c@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-16udp: do not use skb_release_head_state() before skb_attempt_defer_free()Eric Dumazet1-2/+0
Michal reported and bisected an issue after recent adoption of skb_attempt_defer_free() in UDP. The issue here is that skb_release_head_state() is called twice per skb, one time from skb_consume_udp(), then a second time from skb_defer_free_flush() and napi_consume_skb(). As Sabrina suggested, remove skb_release_head_state() call from skb_consume_udp(). Add a DEBUG_NET_WARN_ON_ONCE(skb_nfct(skb)) in skb_attempt_defer_free() Many thanks to Michal, Sabrina, Paolo and Florian for their help. Fixes: 6471658dc66c ("udp: use skb_attempt_defer_free()") Reported-and-bisected-by: Michal Kubecek <mkubecek@suse.cz> Closes: https://lore.kernel.org/netdev/gpjh4lrotyephiqpuldtxxizrsg6job7cvhiqrw72saz2ubs3h@g6fgbvexgl3r/ Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Michal Kubecek <mkubecek@suse.cz> Cc: Sabrina Dubroca <sd@queasysnail.net> Cc: Florian Westphal <fw@strlen.de> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://patch.msgid.link/20251015052715.4140493-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-10-14tcp: fix tcp_tso_should_defer() vs large RTTEric Dumazet1-4/+15
Neal reported that using neper tcp_stream with TCP_TX_DELAY set to 50ms would often lead to flows stuck in a small cwnd mode, regardless of the congestion control. While tcp_stream sets TCP_TX_DELAY too late after the connect(), it highlighted two kernel bugs. The following heuristic in tcp_tso_should_defer() seems wrong for large RTT: delta = tp->tcp_clock_cache - head->tstamp; /* If next ACK is likely to come too late (half srtt), do not defer */ if ((s64)(delta - (u64)NSEC_PER_USEC * (tp->srtt_us >> 4)) < 0) goto send_now; If next ACK is expected to come in more than 1 ms, we should not defer because we prefer a smooth ACK clocking. While blamed commit was a step in the good direction, it was not generic enough. Another patch fixing TCP_TX_DELAY for established flows will be proposed when net-next reopens. Fixes: 50c8339e9299 ("tcp: tso: restore IW10 after TSO autosizing") Reported-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Tested-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20251011115742.1245771-1-edumazet@google.com [pabeni@redhat.com: fixed whitespace issue] Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-10-14net/ip6_tunnel: Prevent perpetual tunnel growthDmitry Safonov1-14/+0
Similarly to ipv4 tunnel, ipv6 version updates dev->needed_headroom, too. While ipv4 tunnel headroom adjustment growth was limited in commit 5ae1e9922bbd ("net: ip_tunnel: prevent perpetual headroom growth"), ipv6 tunnel yet increases the headroom without any ceiling. Reflect ipv4 tunnel headroom adjustment limit on ipv6 version. Credits to Francesco Ruggeri, who was originally debugging this issue and wrote local Arista-specific patch and a reproducer. Fixes: 8eb30be0352d ("ipv6: Create ip6_tnl_xmit") Cc: Florian Westphal <fw@strlen.de> Cc: Francesco Ruggeri <fruggeri05@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Link: https://patch.msgid.link/20251009-ip6_tunnel-headroom-v2-1-8e4dbd8f7e35@arista.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-06tcp: take care of zero tp->window_clamp in tcp_set_rcvlowat()Eric Dumazet1-1/+4
Some applications (like selftests/net/tcp_mmap.c) call SO_RCVLOWAT on their listener, before accept(). This has an unfortunate effect on wscale selection in tcp_select_initial_window() during 3WHS. For instance, tcp_mmap was negotiating wscale 4, regardless of tcp_rmem[2] and sysctl_rmem_max. Do not change tp->window_clamp if it is zero or bigger than our computed value. Zero value is special, it allows tcp_select_initial_window() to enable autotuning. Note that SO_RCVLOWAT use on listener is probably not wise, because tp->scaling_ratio has a default value, possibly wrong. Fixes: d1361840f8c5 ("tcp: fix SO_RCVLOWAT and RCVBUF autotuning") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20251003184119.2526655-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-06tcp: Don't call reqsk_fastopen_remove() in tcp_conn_request().Kuniyuki Iwashima1-1/+0
syzbot reported the splat below in tcp_conn_request(). [0] If a listener is close()d while a TFO socket is being processed in tcp_conn_request(), inet_csk_reqsk_queue_add() does not set reqsk->sk and calls inet_child_forget(), which calls tcp_disconnect() for the TFO socket. After the cited commit, tcp_disconnect() calls reqsk_fastopen_remove(), where reqsk_put() is called due to !reqsk->sk. Then, reqsk_fastopen_remove() in tcp_conn_request() decrements the last req->rsk_refcnt and frees reqsk, and __reqsk_free() at the drop_and_free label causes the refcount underflow for the listener and double-free of the reqsk. Let's remove reqsk_fastopen_remove() in tcp_conn_request(). Note that other callers make sure tp->fastopen_rsk is not NULL. [0]: refcount_t: underflow; use-after-free. WARNING: CPU: 12 PID: 5563 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28) Modules linked in: CPU: 12 UID: 0 PID: 5563 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:refcount_warn_saturate (lib/refcount.c:28) Code: ab e8 8e b4 98 ff 0f 0b c3 cc cc cc cc cc 80 3d a4 e4 d6 01 00 75 9c c6 05 9b e4 d6 01 01 48 c7 c7 e8 df fb ab e8 6a b4 98 ff <0f> 0b e9 03 5b 76 00 cc 80 3d 7d e4 d6 01 00 0f 85 74 ff ff ff c6 RSP: 0018:ffffa79fc0304a98 EFLAGS: 00010246 RAX: d83af4db1c6b3900 RBX: ffff9f65c7a69020 RCX: d83af4db1c6b3900 RDX: 0000000000000000 RSI: 00000000ffff7fff RDI: ffffffffac78a280 RBP: 000000009d781b60 R08: 0000000000007fff R09: ffffffffac6ca280 R10: 0000000000017ffd R11: 0000000000000004 R12: ffff9f65c7b4f100 R13: ffff9f65c7d23c00 R14: ffff9f65c7d26000 R15: ffff9f65c7a64ef8 FS: 00007f9f962176c0(0000) GS:ffff9f65fcf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000180 CR3: 000000000dbbe006 CR4: 0000000000372ef0 Call Trace: <IRQ> tcp_conn_request (./include/linux/refcount.h:400 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/sock.h:1965 ./include/net/request_sock.h:131 net/ipv4/tcp_input.c:7301) tcp_rcv_state_process (net/ipv4/tcp_input.c:6708) tcp_v6_do_rcv (net/ipv6/tcp_ipv6.c:1670) tcp_v6_rcv (net/ipv6/tcp_ipv6.c:1906) ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:438) ip6_input (net/ipv6/ip6_input.c:500) ipv6_rcv (net/ipv6/ip6_input.c:311) __netif_receive_skb (net/core/dev.c:6104) process_backlog (net/core/dev.c:6456) __napi_poll (net/core/dev.c:7506) net_rx_action (net/core/dev.c:7569 net/core/dev.c:7696) handle_softirqs (kernel/softirq.c:579) do_softirq (kernel/softirq.c:480) </IRQ> Fixes: 45c8a6cc2bcd ("tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect().") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20251001233755.1340927-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-03net: psp: don't assume reply skbs will have a socketJakub Kicinski1-1/+1
Rx path may be passing around unreferenced sockets, which means that skb_set_owner_edemux() may not set skb->sk and PSP will crash: KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:psp_reply_set_decrypted (./include/net/psp/functions.h:132 net/psp/psp_sock.c:287) tcp_v6_send_response.constprop.0 (net/ipv6/tcp_ipv6.c:979) tcp_v6_send_reset (net/ipv6/tcp_ipv6.c:1140 (discriminator 1)) tcp_v6_do_rcv (net/ipv6/tcp_ipv6.c:1683) tcp_v6_rcv (net/ipv6/tcp_ipv6.c:1912) Fixes: 659a2899a57d ("tcp: add datapath logic for PSP with inline key exchange") Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20251001022426.2592750-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-03Merge tag 'net-next-6.18' of ↵Linus Torvalds53-1167/+1752
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "Core & protocols: - Improve drop account scalability on NUMA hosts for RAW and UDP sockets and the backlog, almost doubling the Pps capacity under DoS - Optimize the UDP RX performance under stress, reducing contention, revisiting the binary layout of the involved data structs and implementing NUMA-aware locking. This improves UDP RX performance by an additional 50%, even more under extreme conditions - Add support for PSP encryption of TCP connections; this mechanism has some similarities with IPsec and TLS, but offers superior HW offloads capabilities - Ongoing work to support Accurate ECN for TCP. AccECN allows more than one congestion notification signal per RTT and is a building block for Low Latency, Low Loss, and Scalable Throughput (L4S) - Reorganize the TCP socket binary layout for data locality, reducing the number of touched cachelines in the fastpath - Refactor skb deferral free to better scale on large multi-NUMA hosts, this improves TCP and UDP RX performances significantly on such HW - Increase the default socket memory buffer limits from 256K to 4M to better fit modern link speeds - Improve handling of setups with a large number of nexthop, making dump operating scaling linearly and avoiding unneeded synchronize_rcu() on delete - Improve bridge handling of VLAN FDB, storing a single entry per bridge instead of one entry per port; this makes the dump order of magnitude faster on large switches - Restore IP ID correctly for encapsulated packets at GSO segmentation time, allowing GRO to merge packets in more scenarios - Improve netfilter matching performance on large sets - Improve MPTCP receive path performance by leveraging recently introduced core infrastructure (skb deferral free) and adopting recent TCP autotuning changes - Allow bridges to redirect to a backup port when the bridge port is administratively down - Introduce MPTCP 'laminar' endpoint that con be used only once per connection and simplify common MPTCP setups - Add RCU safety to dst->dev, closing a lot of possible races - A significant crypto library API for SCTP, MPTCP and IPv6 SR, reducing code duplication - Supports pulling data from an skb frag into the linear area of an XDP buffer Things we sprinkled into general kernel code: - Generate netlink documentation from YAML using an integrated YAML parser Driver API: - Support using IPv6 Flow Label in Rx hash computation and RSS queue selection - Introduce API for fetching the DMA device for a given queue, allowing TCP zerocopy RX on more H/W setups - Make XDP helpers compatible with unreadable memory, allowing more easily building DevMem-enabled drivers with a unified XDP/skbs datapath - Add a new dedicated ethtool callback enabling drivers to provide the number of RX rings directly, improving efficiency and clarity in RX ring queries and RSS configuration - Introduce a burst period for the health reporter, allowing better handling of multiple errors due to the same root cause - Support for DPLL phase offset exponential moving average, controlling the average smoothing factor Device drivers: - Add a new Huawei driver for 3rd gen NIC (hinic3) - Add a new SpacemiT driver for K1 ethernet MAC - Add a generic abstraction for shared memory communication devices (dibps) - Ethernet high-speed NICs: - nVidia/Mellanox: - Use multiple per-queue doorbell, to avoid MMIO contention issues - support adjacent functions, allowing them to delegate their SR-IOV VFs to sibling PFs - support RSS for IPSec offload - support exposing raw cycle counters in PTP and mlx5 - support for disabling host PFs. - Intel (100G, ice, idpf): - ice: support for SRIOV VFs over an Active-Active link aggregate - ice: support for firmware logging via debugfs - ice: support for Earliest TxTime First (ETF) hardware offload - idpf: support basic XDP functionalities and XSk - Broadcom (bnxt): - support Hyper-V VF ID - dynamic SRIOV resource allocations for RoCE - Meta (fbnic): - support queue API, zero-copy Rx and Tx - support basic XDP functionalities - devlink health support for FW crashes and OTP mem corruptions - expand hardware stats coverage to FEC, PHY, and Pause - Wangxun: - support ethtool coalesce options - support for multiple RSS contexts - Ethernet virtual: - Macsec: - replace custom netlink attribute checks with policy-level checks - Bonding: - support aggregator selection based on port priority - Microsoft vNIC: - use page pool fragments for RX buffers instead of full pages to improve memory efficiency - Ethernet NICs consumer, and embedded: - Qualcomm: support Ethernet function for IPQ9574 SoC - Airoha: implement wlan offloading via NPU - Freescale - enetc: add NETC timer PTP driver and add PTP support - fec: enable the Jumbo frame support for i.MX8QM - Renesas (R-Car S4): - support HW offloading for layer 2 switching - support for RZ/{T2H, N2H} SoCs - Cadence (macb): support TAPRIO traffic scheduling - TI: - support for Gigabit ICSS ethernet SoC (icssm-prueth) - Synopsys (stmmac): a lot of cleanups - Ethernet PHYs: - Support 10g-qxgmi phy-mode for AQR412C, Felix DSA and Lynx PCS driver - Support bcm63268 GPHY power control - Support for Micrel lan8842 PHY and PTP - Support for Aquantia AQR412 and AQR115 - CAN: - a large CAN-XL preparation work - reorganize raw_sock and uniqframe struct to minimize memory usage - rcar_canfd: update the CAN-FD handling - WiFi: - extended Neighbor Awareness Networking (NAN) support - S1G channel representation cleanup - improve S1G support - WiFi drivers: - Intel (iwlwifi): - major refactor and cleanup - Broadcom (brcm80211): - support for AP isolation - RealTek (rtw88/89) rtw88/89: - preparation work for RTL8922DE support - MediaTek (mt76): - HW restart improvements - MLO support - Qualcomm/Atheros (ath10k): - GTK rekey fixes - Bluetooth drivers: - btusb: support for several new IDs for MT7925 - btintel: support for BlazarIW core - btintel_pcie: support for _suspend() / _resume() - btintel_pcie: support for Scorpious, Panther Lake-H484 IDs" * tag 'net-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1536 commits) net: stmmac: Add support for Allwinner A523 GMAC200 dt-bindings: net: sun8i-emac: Add A523 GMAC200 compatible Revert "Documentation: net: add flow control guide and document ethtool API" octeontx2-pf: fix bitmap leak octeontx2-vf: fix bitmap leak net/mlx5e: Use extack in set rxfh callback net/mlx5e: Introduce mlx5e_rss_params for RSS configuration net/mlx5e: Introduce mlx5e_rss_init_params net/mlx5e: Remove unused mdev param from RSS indir init net/mlx5: Improve QoS error messages with actual depth values net/mlx5e: Prevent entering switchdev mode with inconsistent netns net/mlx5: HWS, Generalize complex matchers net/mlx5: Improve write-combining test reliability for ARM64 Grace CPUs selftests/net: add tcp_port_share to .gitignore Revert "net/mlx5e: Update and set Xon/Xoff upon MTU set" net: add NUMA awareness to skb_attempt_defer_free() net: use llist for sd->defer_list net: make softnet_data.defer_count an atomic selftests: drv-net: psp: add tests for destroying devices selftests: drv-net: psp: add test for auto-adjusting TCP MSS ...
2025-09-30tcp: make tcp_rcvbuf_grow() accessible to mptcp codePaolo Abeni1-1/+1
To leverage the auto-tuning improvements brought by commit 2da35e4b4df9 ("Merge branch 'tcp-receive-side-improvements'"), the MPTCP stack need to access the mentioned helper. Acked-by: Geliang Tang <geliang@kernel.org> Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20250927-net-next-mptcp-rcv-path-imp-v1-2-5da266aa9c1a@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-30tcp: use skb->len instead of skb->truesize in tcp_can_ingest()Eric Dumazet1-2/+13
Some applications are stuck to the 20th century and still use small SO_RCVBUF values. After the blamed commit, we can drop packets especially when using LRO/hw-gro enabled NIC and small MSS (1500) values. LRO/hw-gro NIC pack multiple segments into pages, allowing tp->scaling_ratio to be set to a high value. Whenever the receive queue gets full, we can receive a small packet filling RWIN, but with a high skb->truesize, because most NIC use 4K page plus sk_buff metadata even when receiving less than 1500 bytes of payload. Even if we refine how tp->scaling_ratio is estimated, we could have an issue at the start of the flow, because the first round of packets (IW10) will be sent based on the initial tp->scaling_ratio (1/2) Relax tcp_can_ingest() to use skb->len instead of skb->truesize, allowing the peer to use final RWIN, assuming a 'perfect' scaling_ratio of 1. Fixes: 1d2fbaad7cd8 ("tcp: stronger sk_rcvbuf checks") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250927092827.2707901-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-29Merge tag 'namespace-6.18-rc1' of ↵Linus Torvalds2-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull namespace updates from Christian Brauner: "This contains a larger set of changes around the generic namespace infrastructure of the kernel. Each specific namespace type (net, cgroup, mnt, ...) embedds a struct ns_common which carries the reference count of the namespace and so on. We open-coded and cargo-culted so many quirks for each namespace type that it just wasn't scalable anymore. So given there's a bunch of new changes coming in that area I've started cleaning all of this up. The core change is to make it possible to correctly initialize every namespace uniformly and derive the correct initialization settings from the type of the namespace such as namespace operations, namespace type and so on. This leaves the new ns_common_init() function with a single parameter which is the specific namespace type which derives the correct parameters statically. This also means the compiler will yell as soon as someone does something remotely fishy. The ns_common_init() addition also allows us to remove ns_alloc_inum() and drops any special-casing of the initial network namespace in the network namespace initialization code that Linus complained about. Another part is reworking the reference counting. The reference counting was open-coded and copy-pasted for each namespace type even though they all followed the same rules. This also removes all open accesses to the reference count and makes it private and only uses a very small set of dedicated helpers to manipulate them just like we do for e.g., files. In addition this generalizes the mount namespace iteration infrastructure introduced a few cycles ago. As reminder, the vfs makes it possible to iterate sequentially and bidirectionally through all mount namespaces on the system or all mount namespaces that the caller holds privilege over. This allow userspace to iterate over all mounts in all mount namespaces using the listmount() and statmount() system call. Each mount namespace has a unique identifier for the lifetime of the systems that is exposed to userspace. The network namespace also has a unique identifier working exactly the same way. This extends the concept to all other namespace types. The new nstree type makes it possible to lookup namespaces purely by their identifier and to walk the namespace list sequentially and bidirectionally for all namespace types, allowing userspace to iterate through all namespaces. Looking up namespaces in the namespace tree works completely locklessly. This also means we can move the mount namespace onto the generic infrastructure and remove a bunch of code and members from struct mnt_namespace itself. There's a bunch of stuff coming on top of this in the future but for now this uses the generic namespace tree to extend a concept introduced first for pidfs a few cycles ago. For a while now we have supported pidfs file handles for pidfds. This has proven to be very useful. This extends the concept to cover namespaces as well. It is possible to encode and decode namespace file handles using the common name_to_handle_at() and open_by_handle_at() apis. As with pidfs file handles, namespace file handles are exhaustive, meaning it is not required to actually hold a reference to nsfs in able to decode aka open_by_handle_at() a namespace file handle. Instead the FD_NSFS_ROOT constant can be passed which will let the kernel grab a reference to the root of nsfs internally and thus decode the file handle. Namespaces file descriptors can already be derived from pidfds which means they aren't subject to overmount protection bugs. IOW, it's irrelevant if the caller would not have access to an appropriate /proc/<pid>/ns/ directory as they could always just derive the namespace based on a pidfd already. It has the same advantage as pidfds. It's possible to reliably and for the lifetime of the system refer to a namespace without pinning any resources and to compare them trivially. Permission checking is kept simple. If the caller is located in the namespace the file handle refers to they are able to open it otherwise they must hold privilege over the owning namespace of the relevant namespace. The namespace file handle layout is exposed as uapi and has a stable and extensible format. For now it simply contains the namespace identifier, the namespace type, and the inode number. The stable format means that userspace may construct its own namespace file handles without going through name_to_handle_at() as they are already allowed for pidfs and cgroup file handles" * tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (65 commits) ns: drop assert ns: move ns type into struct ns_common nstree: make struct ns_tree private ns: add ns_debug() ns: simplify ns_common_init() further cgroup: add missing ns_common include ns: use inode initializer for initial namespaces selftests/namespaces: verify initial namespace inode numbers ns: rename to __ns_ref nsfs: port to ns_ref_*() helpers net: port to ns_ref_*() helpers uts: port to ns_ref_*() helpers ipv4: use check_net() net: use check_net() net-sysfs: use check_net() user: port to ns_ref_*() helpers time: port to ns_ref_*() helpers pid: port to ns_ref_*() helpers ipc: port to ns_ref_*() helpers cgroup: port to ns_ref_*() helpers ...
2025-09-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+7
Cross-merge networking fixes after downstream PR (net-6.17-rc8). Conflicts: drivers/net/can/spi/hi311x.c 6b6968084721 ("can: hi311x: fix null pointer dereference when resuming from sleep before interface was enabled") 27ce71e1ce81 ("net: WQ_PERCPU added to alloc_workqueue users") https://lore.kernel.org/72ce7599-1b5b-464a-a5de-228ff9724701@kernel.org net/smc/smc_loopback.c drivers/dibs/dibs_loopback.c a35c04de2565 ("net/smc: fix warning in smc_rx_splice() when calling get_page()") cc21191b584c ("dibs: Move data path to dibs layer") https://lore.kernel.org/74368a5c-48ac-4f8e-a198-40ec1ed3cf5f@kernel.org Adjacent changes: drivers/net/dsa/lantiq/lantiq_gswip.c c0054b25e2f1 ("net: dsa: lantiq_gswip: move gswip_add_single_port_br() call to port_setup()") 7a1eaef0a791 ("net: dsa: lantiq_gswip: support model-specific mac_select_pcs()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-25net: gro: remove unnecessary df checksRichard Gobert1-3/+0
Currently, packets with fixed IDs will be merged only if their don't-fragment bit is set. This restriction is unnecessary since packets without the don't-fragment bit will be forwarded as-is even if they were merged together. The merged packets will be segmented into their original forms before being forwarded, either by GSO or by TSO. The IDs will also remain identical unless NETIF_F_TSO_MANGLEID is set, in which case the IDs can become incrementing, which is also fine. Clean up the code by removing the unnecessary don't-fragment checks. Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250923085908.4687-5-richardbgobert@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-25net: gso: restore ids of outer ip headers correctlyRichard Gobert2-11/+8
Currently, NETIF_F_TSO_MANGLEID indicates that the inner-most ID can be mangled. Outer IDs can always be mangled. Make GSO preserve outer IDs by default, with NETIF_F_TSO_MANGLEID allowing both inner and outer IDs to be mangled. This commit also modifies a few drivers that use SKB_GSO_FIXEDID directly. Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Edward Cree <ecree.xilinx@gmail.com> # for sfc Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250923085908.4687-4-richardbgobert@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-25net: gro: only merge packets with incrementing or fixed outer idsRichard Gobert1-1/+4
Only merge encapsulated packets if their outer IDs are either incrementing or fixed, just like for inner IDs and IDs of non-encapsulated packets. Add another ip_fixedid bit for a total of two bits: one for outer IDs (and for unencapsulated packets) and one for inner IDs. This commit preserves the current behavior of GSO where only the IDs of the inner-most headers are restored correctly. Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250923085908.4687-3-richardbgobert@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-25net: gro: remove is_ipv6 from napi_gro_cbRichard Gobert2-20/+14
Remove is_ipv6 from napi_gro_cb and use sk->sk_family instead. This frees up space for another ip_fixedid bit that will be added in the next commit. udp_sock_create always creates either a AF_INET or a AF_INET6 socket, so using sk->sk_family is reliable. In IPv6-FOU, cfg->ipv6_v6only is always enabled. Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250923085908.4687-2-richardbgobert@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-24nexthop: Forbid FDB status change while nexthop is in a groupIdo Schimmel1-0/+7
The kernel forbids the creation of non-FDB nexthop groups with FDB nexthops: # ip nexthop add id 1 via 192.0.2.1 fdb # ip nexthop add id 2 group 1 Error: Non FDB nexthop group cannot have fdb nexthops. And vice versa: # ip nexthop add id 3 via 192.0.2.2 dev dummy1 # ip nexthop add id 4 group 3 fdb Error: FDB nexthop group can only have fdb nexthops. However, as long as no routes are pointing to a non-FDB nexthop group, the kernel allows changing the type of a nexthop from FDB to non-FDB and vice versa: # ip nexthop add id 5 via 192.0.2.2 dev dummy1 # ip nexthop add id 6 group 5 # ip nexthop replace id 5 via 192.0.2.2 fdb # echo $? 0 This configuration is invalid and can result in a NPD [1] since FDB nexthops are not associated with a nexthop device: # ip route add 198.51.100.1/32 nhid 6 # ping 198.51.100.1 Fix by preventing nexthop FDB status change while the nexthop is in a group: # ip nexthop add id 7 via 192.0.2.2 dev dummy1 # ip nexthop add id 8 group 7 # ip nexthop replace id 7 via 192.0.2.2 fdb Error: Cannot change nexthop FDB status while in a group. [1] BUG: kernel NULL pointer dereference, address: 00000000000003c0 [...] Oops: Oops: 0000 [#1] SMP CPU: 6 UID: 0 PID: 367 Comm: ping Not tainted 6.17.0-rc6-virtme-gb65678cacc03 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 RIP: 0010:fib_lookup_good_nhc+0x1e/0x80 [...] Call Trace: <TASK> fib_table_lookup+0x541/0x650 ip_route_output_key_hash_rcu+0x2ea/0x970 ip_route_output_key_hash+0x55/0x80 __ip4_datagram_connect+0x250/0x330 udp_connect+0x2b/0x60 __sys_connect+0x9c/0xd0 __x64_sys_connect+0x18/0x20 do_syscall_64+0xa4/0x2a0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Fixes: 38428d68719c ("nexthop: support for fdb ecmp nexthops") Reported-by: syzbot+6596516dd2b635ba2350@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/68c9a4d2.050a0220.3c6139.0e63.GAE@google.com/ Tested-by: syzbot+6596516dd2b635ba2350@syzkaller.appspotmail.com Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250921150824.149157-2-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-24udp: remove busylock and add per NUMA queuesEric Dumazet1-46/+71
busylock was protecting UDP sockets against packet floods, but unfortunately was not protecting the host itself. Under stress, many cpus could spin while acquiring the busylock, and NIC had to drop packets. Or packets would be dropped in cpu backlog if RPS/RFS were in place. This patch replaces the busylock by intermediate lockless queues. (One queue per NUMA node). This means that fewer number of cpus have to acquire the UDP receive queue lock. Most of the cpus can either: - immediately drop the packet. - or queue it in their NUMA aware lockless queue. Then one of the cpu is chosen to process this lockless queue in a batch. The batch only contains packets that were cooked on the same NUMA node, thus with very limited latency impact. Tested: DDOS targeting a victim UDP socket, on a platform with 6 NUMA nodes (Intel(R) Xeon(R) 6985P-C) Before: nstat -n ; sleep 1 ; nstat | grep Udp Udp6InDatagrams 1004179 0.0 Udp6InErrors 3117 0.0 Udp6RcvbufErrors 3117 0.0 After: nstat -n ; sleep 1 ; nstat | grep Udp Udp6InDatagrams 1116633 0.0 Udp6InErrors 14197275 0.0 Udp6RcvbufErrors 14197275 0.0 We can see this host can now proces 14.2 M more packets per second while under attack, and the victim socket can receive 11 % more packets. I used a small bpftrace program measuring time (in us) spent in __udp_enqueue_schedule_skb(). Before: @udp_enqueue_us[398]: [0] 24901 |@@@ | [1] 63512 |@@@@@@@@@ | [2, 4) 344827 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [4, 8) 244673 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | [8, 16) 54022 |@@@@@@@@ | [16, 32) 222134 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | [32, 64) 232042 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | [64, 128) 4219 | | [128, 256) 188 | | After: @udp_enqueue_us[398]: [0] 5608855 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [1] 1111277 |@@@@@@@@@@ | [2, 4) 501439 |@@@@ | [4, 8) 102921 | | [8, 16) 29895 | | [16, 32) 43500 | | [32, 64) 31552 | | [64, 128) 979 | | [128, 256) 13 | | Note that the remaining bottleneck for this platform is in udp_drops_inc() because we limited struct numa_drop_counters to only two nodes so far. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250922104240.2182559-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-23tcp: Update bind bucket state on port releaseJakub Sitnicki3-5/+52
Today, once an inet_bind_bucket enters a state where fastreuse >= 0 or fastreuseport >= 0 after a socket is explicitly bound to a port, it remains in that state until all sockets are removed and the bucket is destroyed. In this state, the bucket is skipped during ephemeral port selection in connect(). For applications using a reduced ephemeral port range (IP_LOCAL_PORT_RANGE socket option), this can cause faster port exhaustion since blocked buckets are excluded from reuse. The reason the bucket state isn't updated on port release is unclear. Possibly a performance trade-off to avoid scanning bucket owners, or just an oversight. Fix it by recalculating the bucket state when a socket releases a port. To limit overhead, each inet_bind2_bucket stores its own (fastreuse, fastreuseport) state. On port release, only the relevant port-addr bucket is scanned, and the overall state is derived from these. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250917-update-bind-bucket-state-on-unhash-v5-1-57168b661b47@cloudflare.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-23tcp: reclaim 8 bytes in struct request_sock_queueEric Dumazet1-2/+2
synflood_warned had to be u32 for xchg(), but ensuring atomicity is not really needed. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250919204856.2977245-9-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-23tcp: move tcp_clean_acked to tcp_sock_read_tx groupEric Dumazet1-3/+3
tp->tcp_clean_acked is fetched in tx path when snd_una is updated. This field thus belongs to tcp_sock_read_tx group. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250919204856.2977245-7-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-23tcp: move tcp->rcv_tstamp to tcp_sock_write_txrx groupEric Dumazet1-1/+1
tcp_ack() writes this field, it belongs to tcp_sock_write_txrx. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250919204856.2977245-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-23tcp: remove CACHELINE_ASSERT_GROUP_SIZE() usesEric Dumazet1-12/+0
Maintaining the CACHELINE_ASSERT_GROUP_SIZE() uses for struct tcp_sock has been painful. This had little benefit, so remove them. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250919204856.2977245-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-23net: move sk->sk_err_soft and sk->sk_sndbufEric Dumazet1-1/+2
sk->sk_sndbuf is read-mostly in tx path, so move it from sock_write_tx group to more appropriate sock_read_tx. sk->sk_err_soft was not identified previously, but is used from tcp_ack(). Move it to sock_write_tx group for better cache locality. Also change tcp_ack() to clear sk->sk_err_soft only if needed. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250919204856.2977245-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-23net: replace use of system_wq with system_percpu_wqMarco Crivellari1-1/+1
Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. system_unbound_wq should be the default workqueue so as not to enforce locality constraints for random work whenever it's not required. Adding system_dfl_wq to encourage its use when unbound work should be used. The old system_unbound_wq will be kept for a few release cycles. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Marco Crivellari <marco.crivellari@suse.com> Link: https://patch.msgid.link/20250918142427.309519-3-marco.crivellari@suse.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-22tcp: Remove redundant sk_unhashed() in inet_unhash().Kuniyuki Iwashima1-9/+0
inet_unhash() checks sk_unhashed() twice at the entry and after locking ehash/lhash bucket. The former was somehow added redundantly by commit 4f9bf2a2f5aa ("tcp: Don't acquire inet_listen_hashbucket::lock with disabled BH."). inet_unhash() is called for the full socket from 4 places, and it is always under lock_sock() or the socket is not yet published to other threads: 1. __sk_prot_rehash() -> called from inet_sk_reselect_saddr(), which has lockdep_sock_is_held() 2. sk_common_release() -> called when inet_create() or inet6_create() fail, then the socket is not yet published 3. tcp_set_state() -> calls tcp_call_bpf_2arg(), and tcp_call_bpf() has sock_owned_by_me() 4. inet_ctl_sock_create() -> creates a kernel socket and unhashes it immediately, but TCP socket is not hashed in sock_create_kern() (only SOCK_RAW is) So we do not need to check sk_unhashed() twice before/after ehash/lhash lock in inet_unhash(). Let's remove the 2nd one. Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250919083706.1863217-4-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-22tcp: Remove inet6_hash().Kuniyuki Iwashima1-12/+5
inet_hash() and inet6_hash() are exactly the same. Also, we do not need to export inet6_hash(). Let's consolidate the two into __inet_hash() and rename it to inet_hash(). Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250919083706.1863217-3-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-22tcp: Remove osk from __inet_hash() arg.Kuniyuki Iwashima1-3/+3
__inet_hash() is called from inet_hash() and inet6_hash with osk NULL. Let's remove the 2nd arg from __inet_hash(). Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250919083706.1863217-2-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-20net: ipv4: convert ip_rcv_options to drop reasonsAntoine Tenart1-12/+12
This converts the only path not returning drop reasons in ip_rcv_finish_core. Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250915091958.15382-4-atenart@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-20net: ipv4: simplify drop reason handling in ip_rcv_finish_coreAntoine Tenart1-4/+3
Instead of setting the drop reason to SKB_DROP_REASON_NOT_SPECIFIED early and having to reset it each time it is overridden by a function returned value, just set the drop reason to the expected value before returning from ip_rcv_finish_core. Signed-off-by: Antoine Tenart <atenart@kernel.org> Link: https://patch.msgid.link/20250915091958.15382-3-atenart@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-20net: ipv4: make udp_v4_early_demux explicitly return drop reasonAntoine Tenart2-7/+7
udp_v4_early_demux already returns drop reasons as it either returns 0 or ip_mc_validate_source, which itself returns drop reasons. Its return value is also already used as a drop reason itself. Makes this explicit by making it return drop reasons. Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250915091958.15382-2-atenart@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-20tcp: prefer sk_skb_reason_drop()Eric Dumazet1-1/+1
Replace two calls to kfree_skb_reason() with sk_skb_reason_drop(). Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Daniel Zahka <daniel.zahka@gmail.com> Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250918132007.325299-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-19ipv4: use check_net()Christian Brauner2-3/+3
Don't directly acess the namespace count. There's even a dedicated helper for this. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-1/+8
Cross-merge networking fixes after downstream PR (net-6.17-rc7). No conflicts. Adjacent changes: drivers/net/ethernet/mellanox/mlx5/core/en/fs.h 9536fbe10c9d ("net/mlx5e: Add PSP steering in local NIC RX") 7601a0a46216 ("net/mlx5e: Add a miss level for ipsec crypto offload") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-18Merge branch 'add-basic-psp-encryption-for-tcp-connections'Paolo Abeni7-10/+59
Daniel Zahka says: ================== add basic PSP encryption for TCP connections This is v13 of the PSP RFC [1] posted by Jakub Kicinski one year ago. General developments since v1 include a fork of packetdrill [2] with support for PSP added, as well as some test cases, and an implementation of PSP key exchange and connection upgrade [3] integrated into the fbthrift RPC library. Both [2] and [3] have been tested on server platforms with PSP-capable CX7 NICs. Below is the cover letter from the original RFC: Add support for PSP encryption of TCP connections. PSP is a protocol out of Google: https://github.com/google/psp/blob/main/doc/PSP_Arch_Spec.pdf which shares some similarities with IPsec. I added some more info in the first patch so I'll keep it short here. The protocol can work in multiple modes including tunneling. But I'm mostly interested in using it as TLS replacement because of its superior offload characteristics. So this patch does three things: - it adds "core" PSP code PSP is offload-centric, and requires some additional care and feeding, so first chunk of the code exposes device info. This part can be reused by PSP implementations in xfrm, tunneling etc. - TCP integration TLS style Reuse some of the existing concepts from TLS offload, such as attaching crypto state to a socket, marking skbs as "decrypted", egress validation. PSP does not prescribe key exchange protocols. To use PSP as a more efficient TLS offload we intend to perform a TLS handshake ("inline" in the same TCP connection) and negotiate switching to PSP based on capabilities of both endpoints. This is also why I'm not including a software implementation. Nobody would use it in production, software TLS is faster, it has larger crypto records. - mlx5 implementation That's mostly other people's work, not 100% sure those folks consider it ready hence the RFC in the title. But it works :) Not posted, queued a branch [4] are follow up pieces: - standard stats - netdevsim implementation and tests [1] https://lore.kernel.org/netdev/20240510030435.120935-1-kuba@kernel.org/ [2] https://github.com/danieldzahka/packetdrill [3] https://github.com/danieldzahka/fbthrift/tree/dzahka/psp [4] https://github.com/kuba-moo/linux/tree/psp Comments we intend to defer to future series: - we prefer to keep the version field in the tx-assoc netlink request, because it makes parsing keys require less state early on, but we are willing to change in the next version of this series. - using a static branch to wrap psp_enqueue_set_decrypted() and other functions called from tcp. - using INDIRECT_CALL for tls/psp in sk_validate_xmit_skb(). We prefer to address this in a dedicated patch series, so that this series does not need to modify the way tls_validate_xmit_skb() is declared and stubbed out. v12: https://lore.kernel.org/netdev/20250916000559.1320151-1-kuba@kernel.org/ v11: https://lore.kernel.org/20250911014735.118695-1-daniel.zahka@gmail.com v10: https://lore.kernel.org/netdev/20250828162953.2707727-1-daniel.zahka@gmail.com/ v9: https://lore.kernel.org/netdev/20250827155340.2738246-1-daniel.zahka@gmail.com/ v8: https://lore.kernel.org/netdev/20250825200112.1750547-1-daniel.zahka@gmail.com/ v7: https://lore.kernel.org/netdev/20250820113120.992829-1-daniel.zahka@gmail.com/ v6: https://lore.kernel.org/netdev/20250812003009.2455540-1-daniel.zahka@gmail.com/ v5: https://lore.kernel.org/netdev/20250723203454.519540-1-daniel.zahka@gmail.com/ v4: https://lore.kernel.org/netdev/20250716144551.3646755-1-daniel.zahka@gmail.com/ v3: https://lore.kernel.org/netdev/20250702171326.3265825-1-daniel.zahka@gmail.com/ v2: https://lore.kernel.org/netdev/20250625135210.2975231-1-daniel.zahka@gmail.com/ v1: https://lore.kernel.org/netdev/20240510030435.120935-1-kuba@kernel.org/ ================== Links: https://patch.msgid.link/20250917000954.859376-1-daniel.zahka@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> --- * add-basic-psp-encryption-for-tcp-connections: net/mlx5e: Implement PSP key_rotate operation net/mlx5e: Add Rx data path offload psp: provide decapsulation and receive helper for drivers net/mlx5e: Configure PSP Rx flow steering rules net/mlx5e: Add PSP steering in local NIC RX net/mlx5e: Implement PSP Tx data path psp: provide encapsulation helper for drivers net/mlx5e: Implement PSP operations .assoc_add and .assoc_del net/mlx5e: Support PSP offload functionality psp: track generations of device key net: psp: update the TCP MSS to reflect PSP packet overhead net: psp: add socket security association code net: tcp: allow tcp_timewait_sock to validate skbs before handing to device net: move sk_validate_xmit_skb() to net/core/dev.c psp: add op for rotation of device key tcp: add datapath logic for PSP with inline key exchange net: modify core data structures for PSP datapath support psp: base PSP device support psp: add documentation
generated by cgit v1.2.3 (git 2.39.0) at 2026-01-20 20:00:31 +0300