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2024-10-29ipv4: Convert devinet_ioctl to per-netns RTNL.Kuniyuki Iwashima1-2/+2
ioctl(SIOCGIFCONF) calls dev_ifconf() that operates on the current netns. Let's use per-netns RTNL helpers in dev_ifconf() and inet_gifconf(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Convert devinet_ioctl() to per-netns RTNL except for SIOCSIFFLAGS.Kuniyuki Iwashima1-8/+9
Basically, devinet_ioctl() operates on a single netns. However, ioctl(SIOCSIFFLAGS) will trigger the netdev notifier that could touch another netdev in different netns. Let's use per-netns RTNL helper in devinet_ioctl() and place ASSERT_RTNL() for SIOCSIFFLAGS. We will remove ASSERT_RTNL() once RTM_SETLINK and RTM_DELLINK are converted. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Convert devinet_sysctl_forward() to per-netns RTNL.Kuniyuki Iwashima1-3/+3
devinet_sysctl_forward() touches only a single netns. Let's use rtnl_trylock() and __in_dev_get_rtnl_net(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Convert check_lifetime() to per-netns RTNL.Kuniyuki Iwashima1-4/+5
Since commit 1675f385213e ("ipv4: Namespacify IPv4 address GC."), check_lifetime() works on a per-netns basis. Let's use rtnl_net_lock() and rtnl_net_dereference(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Convert RTM_DELADDR to per-netns RTNL.Kuniyuki Iwashima1-9/+15
Let's push down RTNL into inet_rtm_deladdr() as rtnl_net_lock(). Now, ip_mc_autojoin_config() is always called under per-netns RTNL, so ASSERT_RTNL() can be replaced with ASSERT_RTNL_NET(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Use per-netns RTNL helpers in inet_rtm_newaddr().Kuniyuki Iwashima1-4/+4
inet_rtm_to_ifa() and find_matching_ifa() are called under rtnl_net_lock(). __in_dev_get_rtnl() and in_dev_for_each_ifa_rtnl() there can use per-netns RTNL helpers. Let's define and use __in_dev_get_rtnl_net() and in_dev_for_each_ifa_rtnl_net(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Convert RTM_NEWADDR to per-netns RTNL.Kuniyuki Iwashima1-10/+18
The address hash table and GC are already namespacified. Let's push down RTNL into inet_rtm_newaddr() as rtnl_net_lock(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Don't allocate ifa for 0.0.0.0 in inet_rtm_newaddr().Kuniyuki Iwashima1-8/+9
When we pass 0.0.0.0 to __inet_insert_ifa(), it frees ifa and returns 0. We can do this check much earlier for RTM_NEWADDR even before allocating struct in_ifaddr. Let's move the validation to 1. inet_insert_ifa() for ioctl() 2. inet_rtm_newaddr() for RTM_NEWADDR Now, we can remove the same check in find_matching_ifa(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Factorise RTM_NEWADDR validation to inet_validate_rtm().Kuniyuki Iwashima1-35/+44
rtm_to_ifaddr() validates some attributes, looks up a netdev, allocates struct in_ifaddr, and validates IFA_CACHEINFO. There is no reason to delay IFA_CACHEINFO validation. We will push RTNL down to inet_rtm_newaddr(), and then we want to complete rtnetlink validation before rtnl_net_lock(). Let's factorise the validation parts. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netPaolo Abeni1-22/+18
Cross-merge networking fixes after downstream PR. No conflicts and no adjacent changes. Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-24Merge tag 'ipsec-2024-10-22' of ↵Paolo Abeni1-22/+18
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2024-10-22 1) Fix routing behavior that relies on L4 information for xfrm encapsulated packets. From Eyal Birger. 2) Remove leftovers of pernet policy_inexact lists. From Florian Westphal. 3) Validate new SA's prefixlen when the selector family is not set from userspace. From Sabrina Dubroca. 4) Fix a kernel-infoleak when dumping an auth algorithm. From Petr Vaganov. Please pull or let me know if there are problems. ipsec-2024-10-22 * tag 'ipsec-2024-10-22' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec: xfrm: fix one more kernel-infoleak in algo dumping xfrm: validate new SA's prefixlen using SA family when sel.family is unset xfrm: policy: remove last remnants of pernet inexact list xfrm: respect ip protocols rules criteria when performing dst lookups xfrm: extract dst lookup parameters into a struct ==================== Link: https://patch.msgid.link/20241022092226.654370-1-steffen.klassert@secunet.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-23ipv4: Switch inet_addr_hash() to less predictable hash.Kuniyuki Iwashima1-1/+1
Recently, commit 4a0ec2aa0704 ("ipv6: switch inet6_addr_hash() to less predictable hash") and commit 4daf4dc275f1 ("ipv6: switch inet6_acaddr_hash() to less predictable hash") hardened IPv6 address hash functions. inet_addr_hash() is also highly predictable, and a malicious use could abuse a specific bucket. Let's follow the change on IPv4 by using jhash_1word(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241018014100.93776-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-22tools: ynl-gen: use big-endian netlink attribute typesAsbjørn Sloth Tønnesen1-2/+2
Change ynl-gen-c.py to use NLA_BE16 and NLA_BE32 types to represent big-endian u16 and u32 ynl types. Doing this enables those attributes to have range checks applied, as the validator will then convert to host endianness prior to validation. The autogenerated kernel/uapi code have been regenerated by running: ./tools/net/ynl/ynl-regen.sh -f This changes the policy types of the following attributes: FOU_ATTR_PORT (NLA_U16 -> NLA_BE16) FOU_ATTR_PEER_PORT (NLA_U16 -> NLA_BE16) These two are used with nla_get_be16/nla_put_be16(). MPTCP_PM_ADDR_ATTR_ADDR4 (NLA_U32 -> NLA_BE32) This one is used with nla_get_in_addr/nla_put_in_addr(), which uses nla_get_be32/nla_put_be32(). IOWs the generated changes are AFAICT aligned with their implementations. The generated userspace code remains identical, and have been verified by comparing the output generated by the following command: make -C tools/net/ynl/generated Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20241017094704.3222173-1-ast@fiberby.net Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-22rtnetlink: Return int from rtnl_af_register().Kuniyuki Iwashima1-1/+2
The next patch will add init_srcu_struct() in rtnl_af_register(), then we need to handle its error. Let's add the error handling in advance to make the following patch cleaner. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Matt Johnston <matt@codeconstruct.com.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netPaolo Abeni3-16/+44
Cross-merge networking fixes after downstream PR (net-6.12-rc4). Conflicts: 107a034d5c1e ("net/mlx5: qos: Store rate groups in a qos domain") 1da9cfd6c41c ("net/mlx5: Unregister notifier on eswitch init failure") Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-16ipmr: Use rtnl_register_many().Kuniyuki Iwashima1-9/+13
We will remove rtnl_register() and rtnl_register_module() in favour of rtnl_register_many(). When it succeeds for built-in callers, rtnl_register_many() guarantees all rtnetlink types in the passed array are supported, and there is no chance that a part of message types is not supported. Let's use rtnl_register_many() instead. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241014201828.91221-9-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-16ipv4: Use rtnl_register_many().Kuniyuki Iwashima4-26/+45
We will remove rtnl_register() in favour of rtnl_register_many(). When it succeeds, rtnl_register_many() guarantees all rtnetlink types in the passed array are supported, and there is no chance that a part of message types is not supported. Let's use rtnl_register_many() instead. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241014201828.91221-7-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-16net: inet: do not leave a dangling sk pointer in inet_create()Ignat Korchagin1-12/+10
sock_init_data() attaches the allocated sk object to the provided sock object. If inet_create() fails later, the sk object is freed, but the sock object retains the dangling pointer, which may create use-after-free later. Clear the sk pointer in the sock object on error. Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241014153808.51894-7-ignat@cloudflare.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-16udp: Compute L4 checksum as usual when not segmenting the skbJakub Sitnicki1-1/+3
If: 1) the user requested USO, but 2) there is not enough payload for GSO to kick in, and 3) the egress device doesn't offer checksum offload, then we want to compute the L4 checksum in software early on. In the case when we are not taking the GSO path, but it has been requested, the software checksum fallback in skb_segment doesn't get a chance to compute the full checksum, if the egress device can't do it. As a result we end up sending UDP datagrams with only a partial checksum filled in, which the peer will discard. Fixes: 10154dbded6d ("udp: Allow GSO transmit from devices with no checksum offload") Reported-by: Ivan Babrou <ivan@cloudflare.com> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20241011-uso-swcsum-fixup-v2-1-6e1ddc199af9@cloudflare.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-16tcp/dccp: Don't use timer_pending() in reqsk_queue_unlink().Kuniyuki Iwashima1-5/+16
Martin KaFai Lau reported use-after-free [0] in reqsk_timer_handler(). """ We are seeing a use-after-free from a bpf prog attached to trace_tcp_retransmit_synack. The program passes the req->sk to the bpf_sk_storage_get_tracing kernel helper which does check for null before using it. """ The commit 83fccfc3940c ("inet: fix potential deadlock in reqsk_queue_unlink()") added timer_pending() in reqsk_queue_unlink() not to call del_timer_sync() from reqsk_timer_handler(), but it introduced a small race window. Before the timer is called, expire_timers() calls detach_timer(timer, true) to clear timer->entry.pprev and marks it as not pending. If reqsk_queue_unlink() checks timer_pending() just after expire_timers() calls detach_timer(), TCP will miss del_timer_sync(); the reqsk timer will continue running and send multiple SYN+ACKs until it expires. The reported UAF could happen if req->sk is close()d earlier than the timer expiration, which is 63s by default. The scenario would be 1. inet_csk_complete_hashdance() calls inet_csk_reqsk_queue_drop(), but del_timer_sync() is missed 2. reqsk timer is executed and scheduled again 3. req->sk is accept()ed and reqsk_put() decrements rsk_refcnt, but reqsk timer still has another one, and inet_csk_accept() does not clear req->sk for non-TFO sockets 4. sk is close()d 5. reqsk timer is executed again, and BPF touches req->sk Let's not use timer_pending() by passing the caller context to __inet_csk_reqsk_queue_drop(). Note that reqsk timer is pinned, so the issue does not happen in most use cases. [1] [0] BUG: KFENCE: use-after-free read in bpf_sk_storage_get_tracing+0x2e/0x1b0 Use-after-free read at 0x00000000a891fb3a (in kfence-#1): bpf_sk_storage_get_tracing+0x2e/0x1b0 bpf_prog_5ea3e95db6da0438_tcp_retransmit_synack+0x1d20/0x1dda bpf_trace_run2+0x4c/0xc0 tcp_rtx_synack+0xf9/0x100 reqsk_timer_handler+0xda/0x3d0 run_timer_softirq+0x292/0x8a0 irq_exit_rcu+0xf5/0x320 sysvec_apic_timer_interrupt+0x6d/0x80 asm_sysvec_apic_timer_interrupt+0x16/0x20 intel_idle_irq+0x5a/0xa0 cpuidle_enter_state+0x94/0x273 cpu_startup_entry+0x15e/0x260 start_secondary+0x8a/0x90 secondary_startup_64_no_verify+0xfa/0xfb kfence-#1: 0x00000000a72cc7b6-0x00000000d97616d9, size=2376, cache=TCPv6 allocated by task 0 on cpu 9 at 260507.901592s: sk_prot_alloc+0x35/0x140 sk_clone_lock+0x1f/0x3f0 inet_csk_clone_lock+0x15/0x160 tcp_create_openreq_child+0x1f/0x410 tcp_v6_syn_recv_sock+0x1da/0x700 tcp_check_req+0x1fb/0x510 tcp_v6_rcv+0x98b/0x1420 ipv6_list_rcv+0x2258/0x26e0 napi_complete_done+0x5b1/0x2990 mlx5e_napi_poll+0x2ae/0x8d0 net_rx_action+0x13e/0x590 irq_exit_rcu+0xf5/0x320 common_interrupt+0x80/0x90 asm_common_interrupt+0x22/0x40 cpuidle_enter_state+0xfb/0x273 cpu_startup_entry+0x15e/0x260 start_secondary+0x8a/0x90 secondary_startup_64_no_verify+0xfa/0xfb freed by task 0 on cpu 9 at 260507.927527s: rcu_core_si+0x4ff/0xf10 irq_exit_rcu+0xf5/0x320 sysvec_apic_timer_interrupt+0x6d/0x80 asm_sysvec_apic_timer_interrupt+0x16/0x20 cpuidle_enter_state+0xfb/0x273 cpu_startup_entry+0x15e/0x260 start_secondary+0x8a/0x90 secondary_startup_64_no_verify+0xfa/0xfb Fixes: 83fccfc3940c ("inet: fix potential deadlock in reqsk_queue_unlink()") Reported-by: Martin KaFai Lau <martin.lau@kernel.org> Closes: https://lore.kernel.org/netdev/eb6684d0-ffd9-4bdc-9196-33f690c25824@linux.dev/ Link: https://lore.kernel.org/netdev/b55e2ca0-42f2-4b7c-b445-6ffd87ca74a0@linux.dev/ [1] Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20241014223312.4254-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-15inetpeer: replace call_rcu by kfree_rcu for simple kmem_cache_free callbackJulia Lawall1-7/+2
Since SLOB was removed and since commit 6c6c47b063b5 ("mm, slab: call kvfree_rcu_barrier() from kmem_cache_destroy()"), it is not necessary to use call_rcu when the callback only performs kmem_cache_free. Use kfree_rcu() directly. The changes were made using Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Link: https://patch.msgid.link/20241013201704.49576-4-Julia.Lawall@inria.fr Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-15ipv4: replace call_rcu by kfree_rcu for simple kmem_cache_free callbackJulia Lawall1-7/+1
Since SLOB was removed and since commit 6c6c47b063b5 ("mm, slab: call kvfree_rcu_barrier() from kmem_cache_destroy()"), it is not necessary to use call_rcu when the callback only performs kmem_cache_free. Use kfree_rcu() directly. The changes were made using Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Link: https://patch.msgid.link/20241013201704.49576-3-Julia.Lawall@inria.fr Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-15netfilter: Make legacy configs user selectableBreno Leitao1-2/+14
This option makes legacy Netfilter Kconfig user selectable, giving users the option to configure iptables without enabling any other config. Make the following KConfig entries user selectable: * BRIDGE_NF_EBTABLES_LEGACY * IP_NF_ARPTABLES * IP_NF_IPTABLES_LEGACY * IP6_NF_IPTABLES_LEGACY Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-10-15ipv4: tcp: give socket pointer to control skbsEric Dumazet2-3/+6
ip_send_unicast_reply() send orphaned 'control packets'. These are RST packets and also ACK packets sent from TIME_WAIT. Some eBPF programs would prefer to have a meaningful skb->sk pointer as much as possible. This means that TCP can now attach TIME_WAIT sockets to outgoing skbs. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Brian Vazquez <brianvv@google.com> Link: https://patch.msgid.link/20241010174817.1543642-6-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-15net: add skb_set_owner_edemux() helperEric Dumazet1-1/+1
This can be used to attach a socket to an skb, taking a reference on sk->sk_refcnt. This helper might be a NOP if sk->sk_refcnt is zero. Use it from tcp_make_synack(). Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Brian Vazquez <brianvv@google.com> Link: https://patch.msgid.link/20241010174817.1543642-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-12ipv4: give an IPv4 dev to blackhole_netdevXin Long1-10/+25
After commit 8d7017fd621d ("blackhole_netdev: use blackhole_netdev to invalidate dst entries"), blackhole_netdev was introduced to invalidate dst cache entries on the TX path whenever the cache times out or is flushed. When two UDP sockets (sk1 and sk2) send messages to the same destination simultaneously, they are using the same dst cache. If the dst cache is invalidated on one path (sk2) while the other (sk1) is still transmitting, sk1 may try to use the invalid dst entry. CPU1 CPU2 udp_sendmsg(sk1) udp_sendmsg(sk2) udp_send_skb() ip_output() <--- dst timeout or flushed dst_dev_put() ip_finish_output2() ip_neigh_for_gw() This results in a scenario where ip_neigh_for_gw() returns -EINVAL because blackhole_dev lacks an in_dev, which is needed to initialize the neigh in arp_constructor(). This error is then propagated back to userspace, breaking the UDP application. The patch fixes this issue by assigning an in_dev to blackhole_dev for IPv4, similar to what was done for IPv6 in commit e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"). This ensures that even when the dst entry is invalidated with blackhole_dev, it will not fail to create the neigh entry. As devinet_init() is called ealier than blackhole_netdev_init() in system booting, it can not assign the in_dev to blackhole_dev in devinet_init(). As Paolo suggested, add a separate late_initcall() in devinet.c to ensure inet_blackhole_dev_init() is called after blackhole_netdev_init(). Fixes: 8d7017fd621d ("blackhole_netdev: use blackhole_netdev to invalidate dst entries") Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/3000792d45ca44e16c785ebe2b092e610e5b3df1.1728499633.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-12net: do not acquire rtnl in fib_seq_sum()Eric Dumazet2-2/+2
After we made sure no fib_seq_read() handlers needs RTNL anymore, we can remove RTNL from fib_seq_sum(). Note that after RTNL was dropped, fib_seq_sum() result was possibly outdated anyway. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20241009184405.3752829-6-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-12ipmr: use READ_ONCE() to read net->ipv[46].ipmr_seqEric Dumazet1-5/+3
mr_call_vif_notifiers() and mr_call_mfc_notifiers() already uses WRITE_ONCE() on the write side. Using RTNL to protect the reads seems a big hammer. Constify 'struct net' argument of ip6mr_rules_seq_read() and ipmr_rules_seq_read(). Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20241009184405.3752829-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-12ipv4: use READ_ONCE()/WRITE_ONCE() on net->ipv4.fib_seqEric Dumazet2-5/+5
Using RTNL to protect ops->fib_rules_seq reads seems a big hammer. Writes are protected by RTNL. We can use READ_ONCE() when reading it. Constify 'struct net' argument of fib4_rules_seq_read() Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20241009184405.3752829-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-11/+40
Cross-merge networking fixes after downstream PR (net-6.12-rc3). No conflicts and no adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10Merge tag 'nf-24-10-09' of ↵Paolo Abeni1-3/+1
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: 1) Restrict xtables extensions to families that are safe, syzbot found a way to combine ebtables with extensions that are never used by userspace tools. From Florian Westphal. 2) Set l3mdev inconditionally whenever possible in nft_fib to fix lookup mismatch, also from Florian. netfilter pull request 24-10-09 * tag 'nf-24-10-09' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: selftests: netfilter: conntrack_vrf.sh: add fib test case netfilter: fib: check correct rtable in vrf setups netfilter: xtables: avoid NFPROTO_UNSPEC where needed ==================== Link: https://patch.msgid.link/20241009213858.3565808-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-10ipv4: Retire global IPv4 hash table inet_addr_lst.Kuniyuki Iwashima1-10/+0
No one uses inet_addr_lst anymore, so let's remove it. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20241008172906.1326-5-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Namespacify IPv4 address GC.Kuniyuki Iwashima1-14/+18
Each IPv4 address could have a lifetime, which is useful for DHCP, and GC is periodically executed as check_lifetime_work. check_lifetime() does the actual GC under RTNL. 1. Acquire RTNL 2. Iterate inet_addr_lst 3. Remove IPv4 address if expired 4. Release RTNL Namespacifying the GC is required for per-netns RTNL, but using the per-netns hash table will shorten the time on the hash bucket iteration under RTNL. Let's add per-netns GC work and use the per-netns hash table. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20241008172906.1326-4-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Use per-netns hash table in inet_lookup_ifaddr_rcu().Kuniyuki Iwashima1-3/+2
Now, all IPv4 addresses are put in the per-netns hash table. Let's use it in inet_lookup_ifaddr_rcu(). Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20241008172906.1326-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Link IPv4 address to per-netns hash table.Kuniyuki Iwashima1-3/+19
As a prep for per-netns RTNL conversion, we want to namespacify the IPv4 address hash table and the GC work. Let's allocate the per-netns IPv4 address hash table to net->ipv4.inet_addr_lst and link IPv4 addresses into it. The actual users will be converted later. Note that the IPv6 address hash table is already namespacified. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20241008172906.1326-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10tcp: fix mptcp DSS corruption due to large pmtu xmitPaolo Abeni1-4/+1
Syzkaller was able to trigger a DSS corruption: TCP: request_sock_subflow_v4: Possible SYN flooding on port [::]:20002. Sending cookies. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5227 at net/mptcp/protocol.c:695 __mptcp_move_skbs_from_subflow+0x20a9/0x21f0 net/mptcp/protocol.c:695 Modules linked in: CPU: 0 UID: 0 PID: 5227 Comm: syz-executor350 Not tainted 6.11.0-syzkaller-08829-gaf9c191ac2a0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:__mptcp_move_skbs_from_subflow+0x20a9/0x21f0 net/mptcp/protocol.c:695 Code: 0f b6 dc 31 ff 89 de e8 b5 dd ea f5 89 d8 48 81 c4 50 01 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc e8 98 da ea f5 90 <0f> 0b 90 e9 47 ff ff ff e8 8a da ea f5 90 0f 0b 90 e9 99 e0 ff ff RSP: 0018:ffffc90000006db8 EFLAGS: 00010246 RAX: ffffffff8ba9df18 RBX: 00000000000055f0 RCX: ffff888030023c00 RDX: 0000000000000100 RSI: 00000000000081e5 RDI: 00000000000055f0 RBP: 1ffff110062bf1ae R08: ffffffff8ba9cf12 R09: 1ffff110062bf1b8 R10: dffffc0000000000 R11: ffffed10062bf1b9 R12: 0000000000000000 R13: dffffc0000000000 R14: 00000000700cec61 R15: 00000000000081e5 FS: 000055556679c380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020287000 CR3: 0000000077892000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> move_skbs_to_msk net/mptcp/protocol.c:811 [inline] mptcp_data_ready+0x29c/0xa90 net/mptcp/protocol.c:854 subflow_data_ready+0x34a/0x920 net/mptcp/subflow.c:1490 tcp_data_queue+0x20fd/0x76c0 net/ipv4/tcp_input.c:5283 tcp_rcv_established+0xfba/0x2020 net/ipv4/tcp_input.c:6237 tcp_v4_do_rcv+0x96d/0xc70 net/ipv4/tcp_ipv4.c:1915 tcp_v4_rcv+0x2dc0/0x37f0 net/ipv4/tcp_ipv4.c:2350 ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5662 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcb/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 </IRQ> <TASK> __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline] __dev_queue_xmit+0x1764/0x3e80 net/core/dev.c:4451 dev_queue_xmit include/linux/netdevice.h:3094 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:236 ip_local_out net/ipv4/ip_output.c:130 [inline] __ip_queue_xmit+0x118c/0x1b80 net/ipv4/ip_output.c:536 __tcp_transmit_skb+0x2544/0x3b30 net/ipv4/tcp_output.c:1466 tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline] tcp_mtu_probe net/ipv4/tcp_output.c:2547 [inline] tcp_write_xmit+0x641d/0x6bf0 net/ipv4/tcp_output.c:2752 __tcp_push_pending_frames+0x9b/0x360 net/ipv4/tcp_output.c:3015 tcp_push_pending_frames include/net/tcp.h:2107 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5714 [inline] tcp_rcv_established+0x1026/0x2020 net/ipv4/tcp_input.c:6239 tcp_v4_do_rcv+0x96d/0xc70 net/ipv4/tcp_ipv4.c:1915 sk_backlog_rcv include/net/sock.h:1113 [inline] __release_sock+0x214/0x350 net/core/sock.c:3072 release_sock+0x61/0x1f0 net/core/sock.c:3626 mptcp_push_release net/mptcp/protocol.c:1486 [inline] __mptcp_push_pending+0x6b5/0x9f0 net/mptcp/protocol.c:1625 mptcp_sendmsg+0x10bb/0x1b10 net/mptcp/protocol.c:1903 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2603 ___sys_sendmsg net/socket.c:2657 [inline] __sys_sendmsg+0x2aa/0x390 net/socket.c:2686 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb06e9317f9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe2cfd4f98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fb06e97f468 RCX: 00007fb06e9317f9 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000005 RBP: 00007fb06e97f446 R08: 0000555500000000 R09: 0000555500000000 R10: 0000555500000000 R11: 0000000000000246 R12: 00007fb06e97f406 R13: 0000000000000001 R14: 00007ffe2cfd4fe0 R15: 0000000000000003 </TASK> Additionally syzkaller provided a nice reproducer. The repro enables pmtu on the loopback device, leading to tcp_mtu_probe() generating very large probe packets. tcp_can_coalesce_send_queue_head() currently does not check for mptcp-level invariants, and allowed the creation of cross-DSS probes, leading to the mentioned corruption. Address the issue teaching tcp_can_coalesce_send_queue_head() about mptcp using the tcp_skb_can_collapse(), also reducing the code duplication. Fixes: 85712484110d ("tcp: coalesce/collapse must respect MPTCP extensions") Cc: stable@vger.kernel.org Reported-by: syzbot+d1bff73460e33101f0e7@syzkaller.appspotmail.com Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/513 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20241008-net-mptcp-fallback-fixes-v1-2-c6fb8e93e551@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10tcp: remove unnecessary update for tp->write_seq in tcp_connect()xin.guo1-1/+4
Commit 783237e8daf13 ("net-tcp: Fast Open client - sending SYN-data") introduces tcp_connect_queue_skb() and it would overwrite tcp->write_seq, so it is no need to update tp->write_seq before invoking tcp_connect_queue_skb(). Signed-off-by: xin.guo <guoxin0309@gmail.com> Link: https://patch.msgid.link/1728289544-4611-1-git-send-email-guoxin0309@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Convert __fib_validate_source() to dscp_t.Guillaume Nault1-4/+4
Pass a dscp_t variable to __fib_validate_source(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Only fib_validate_source() actually calls __fib_validate_source(). Since it already has a dscp_t variable to pass as parameter, we only need to remove the inet_dscp_to_dsfield() conversion. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/8206b0a64a21a208ed94774e261a251c8d7bc251.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Convert fib_validate_source() to dscp_t.Guillaume Nault2-14/+12
Pass a dscp_t variable to fib_validate_source(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. All callers of fib_validate_source() already have a dscp_t variable to pass as parameter. We just need to remove the inet_dscp_to_dsfield() conversions. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/08612a4519bc5a3578bb493fbaad82437ebb73dc.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Convert ip_mc_validate_source() to dscp_t.Guillaume Nault2-6/+6
Pass a dscp_t variable to ip_mc_validate_source(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Callers of ip_mc_validate_source() to consider are: * ip_route_input_mc() which already has a dscp_t variable to pass as parameter. We just need to remove the inet_dscp_to_dsfield() conversion. * udp_v4_early_demux() which gets the DSCP directly from the IPv4 header and can simply use the ip4h_dscp() helper. Also, stop including net/inet_dscp.h in udp.c as we don't use any of its declarations anymore. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/c91b2cca04718b7ee6cf5b9c1d5b40507d65a8d4.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Convert ip_route_input_mc() to dscp_t.Guillaume Nault1-5/+6
Pass a dscp_t variable to ip_route_input_mc(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Only ip_route_input_rcu() actually calls ip_route_input_mc(). Since it already has a dscp_t variable to pass as parameter, we only need to remove the inet_dscp_to_dsfield() conversion. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/0cc653ef59bbc0a28881f706d34896c61eba9e01.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Convert __mkroute_input() to dscp_t.Guillaume Nault1-8/+6
Pass a dscp_t variable to __mkroute_input(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Only ip_mkroute_input() actually calls __mkroute_input(). Since it already has a dscp_t variable to pass as parameter, we only need to remove the inet_dscp_to_dsfield() conversion. While there, reorganise the function parameters to fill up horizontal space. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/40853c720aee4d608e6b1b204982164c3b76697d.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Convert ip_mkroute_input() to dscp_t.Guillaume Nault1-8/+6
Pass a dscp_t variable to ip_mkroute_input(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Only ip_route_input_slow() actually calls ip_mkroute_input(). Since it already has a dscp_t variable to pass as parameter, we only need to remove the inet_dscp_to_dsfield() conversion. While there, reorganise the function parameters to fill up horizontal space. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/6aa71e28f9ff681cbd70847080e1ab6b526f94f1.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10ipv4: Convert ip_route_use_hint() to dscp_t.Guillaume Nault2-5/+5
Pass a dscp_t variable to ip_route_use_hint(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Only ip_rcv_finish_core() actually calls ip_route_use_hint(). Use the ip4h_dscp() helper to get the DSCP from the IPv4 header. While there, modify the declaration of ip_route_use_hint() in include/net/route.h so that it matches the prototype of its implementation in net/ipv4/route.c. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/c40994fdf804db7a363d04fdee01bf48dddda676.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10netfilter: fib: check correct rtable in vrf setupsFlorian Westphal1-3/+1
We need to init l3mdev unconditionally, else main routing table is searched and incorrect result is returned unless strict (iif keyword) matching is requested. Next patch adds a selftest for this. Fixes: 2a8a7c0eaa87 ("netfilter: nft_fib: Fix for rpath check with VRF devices") Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1761 Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-10-09net: ipv4: igmp: optimize ____ip_mc_inc_group() using mc_hashJonas Rebmann1-5/+21
The runtime cost of joining a single multicast group in the current implementation of ____ip_mc_inc_group grows linearly with the number of existing memberships. This is caused by the linear search for an existing group record in the multicast address list. This linear complexity results in quadratic complexity when successively adding memberships, which becomes a performance bottleneck when setting up large numbers of multicast memberships. If available, use the existing multicast hash map mc_hash to quickly search for an existing group membership record. This leads to near-constant complexity on the addition of a new multicast record, significantly improving performance for workloads involving many multicast memberships. On profiling with a loopback device, this patch presented a speedup of around 6 when successively setting up 2000 multicast groups using setsockopt without measurable drawbacks on smaller numbers of multicast groups. Signed-off-by: Jonas Rebmann <jre@pengutronix.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-10-08ipv4: remove fib_info_devhash[]Eric Dumazet1-20/+15
Upcoming per-netns RTNL conversion needs to get rid of shared hash tables. fib_info_devhash[] is one of them. It is unclear why we used a hash table, because a single hlist_head per net device was cheaper and scalable. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20241004134720.579244-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-08ipv4: remove fib_info_lockEric Dumazet1-12/+6
After the prior patch, fib_info_lock became redundant because all of its users are holding RTNL. BH protection is not needed. Remove the READ_ONCE()/WRITE_ONCE() annotations around fib_info_cnt, since it is protected by RTNL. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20241004134720.579244-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-08ipv4: use rcu in ip_fib_check_default()Eric Dumazet1-9/+4
fib_info_devhash[] is not resized in fib_info_hash_move(). fib_nh structs are already freed after an rcu grace period. This will allow to remove fib_info_lock in the following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20241004134720.579244-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-08ipv4: remove fib_devindex_hashfn()Eric Dumazet1-9/+4
fib_devindex_hashfn() converts a 32bit ifindex value to a 8bit hash. It makes no sense doing this from fib_info_hashfn() and fib_find_info_nh(). It is better to keep as many bits as possible to let fib_info_hashfn_result() have better spread. Only fib_info_devhash_bucket() needs to make this operation, we can 'inline' trivial fib_devindex_hashfn() in it. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20241004134720.579244-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>