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2022-10-12treewide: use prandom_u32_max() when possible, part 1Jason A. Donenfeld1-1/+1
Rather than incurring a division or requesting too many random bytes for the given range, use the prandom_u32_max() function, which only takes the minimum required bytes from the RNG and avoids divisions. This was done mechanically with this coccinelle script: @basic@ expression E; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u64; @@ ( - ((T)get_random_u32() % (E)) + prandom_u32_max(E) | - ((T)get_random_u32() & ((E) - 1)) + prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2) | - ((u64)(E) * get_random_u32() >> 32) + prandom_u32_max(E) | - ((T)get_random_u32() & ~PAGE_MASK) + prandom_u32_max(PAGE_SIZE) ) @multi_line@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; identifier RAND; expression E; @@ - RAND = get_random_u32(); ... when != RAND - RAND %= (E); + RAND = prandom_u32_max(E); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Add one to the literal. @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1: print("Skipping 0x%x for cleanup elsewhere" % (value)) cocci.include_match(False) elif value & (value + 1) != 0: print("Skipping 0x%x because it's not a power of two minus one" % (value)) cocci.include_match(False) elif literal.startswith('0x'): coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1)) else: coccinelle.RESULT = cocci.make_expr("%d" % (value + 1)) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; expression add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + prandom_u32_max(RESULT) @collapse_ret@ type T; identifier VAR; expression E; @@ { - T VAR; - VAR = (E); - return VAR; + return E; } @drop_var@ type T; identifier VAR; @@ { - T VAR; ... when != VAR } Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: KP Singh <kpsingh@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-08-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-3/+9
drivers/net/ethernet/mellanox/mlx5/core/en_fs.c 21234e3a84c7 ("net/mlx5e: Fix use after free in mlx5e_fs_init()") c7eafc5ed068 ("net/mlx5e: Convert ethtool_steering member of flow_steering struct to pointer") https://lore.kernel.org/all/20220825104410.67d4709c@canb.auug.org.au/ https://lore.kernel.org/all/20220823055533.334471-1-saeed@kernel.org/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-24net: neigh: don't call kfree_skb() under spin_lock_irqsave()Yang Yingliang1-3/+9
It is not allowed to call kfree_skb() from hardware interrupt context or with interrupts being disabled. So add all skb to a tmp list, then free them after spin_unlock_irqrestore() at once. Fixes: 66ba215cb513 ("neigh: fix possible DoS due to net iface start/stop loop") Suggested-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-22Remove DECnet support from kernelStephen Hemminger1-3/+0
DECnet is an obsolete network protocol that receives more attention from kernel janitors than users. It belongs in computer protocol history museum not in Linux kernel. It has been "Orphaned" in kernel since 2010. The iproute2 support for DECnet was dropped in 5.0 release. The documentation link on Sourceforge says it is abandoned there as well. Leave the UAPI alone to keep userspace programs compiling. This means that there is still an empty neighbour table for AF_DECNET. The table of /proc/sys/net entries was updated to match current directories and reformatted to be alphabetical. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Acked-by: David Ahern <dsahern@kernel.org> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-15neighbour: make proxy_queue.qlen limit per-deviceAlexander Mikhalitsyn1-3/+22
Right now we have a neigh_param PROXY_QLEN which specifies maximum length of neigh_table->proxy_queue. But in fact, this limitation doesn't work well because check condition looks like: tbl->proxy_queue.qlen > NEIGH_VAR(p, PROXY_QLEN) The problem is that p (struct neigh_parms) is a per-device thing, but tbl (struct neigh_table) is a system-wide global thing. It seems reasonable to make proxy_queue limit per-device based. v2: - nothing changed in this patch v3: - rebase to net tree Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@kernel.org> Cc: Yajun Deng <yajun.deng@linux.dev> Cc: Roopa Prabhu <roopa@nvidia.com> Cc: Christian Brauner <brauner@kernel.org> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com> Cc: Konstantin Khorenko <khorenko@virtuozzo.com> Cc: kernel@openvz.org Cc: devel@openvz.org Suggested-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com> Reviewed-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-15neigh: fix possible DoS due to net iface start/stop loopDenis V. Lunev1-8/+17
Normal processing of ARP request (usually this is Ethernet broadcast packet) coming to the host is looking like the following: * the packet comes to arp_process() call and is passed through routing procedure * the request is put into the queue using pneigh_enqueue() if corresponding ARP record is not local (common case for container records on the host) * the request is processed by timer (within 80 jiffies by default) and ARP reply is sent from the same arp_process() using NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED condition (flag is set inside pneigh_enqueue()) And here the problem comes. Linux kernel calls pneigh_queue_purge() which destroys the whole queue of ARP requests on ANY network interface start/stop event through __neigh_ifdown(). This is actually not a problem within the original world as network interface start/stop was accessible to the host 'root' only, which could do more destructive things. But the world is changed and there are Linux containers available. Here container 'root' has an access to this API and could be considered as untrusted user in the hosting (container's) world. Thus there is an attack vector to other containers on node when container's root will endlessly start/stop interfaces. We have observed similar situation on a real production node when docker container was doing such activity and thus other containers on the node become not accessible. The patch proposed doing very simple thing. It drops only packets from the same namespace in the pneigh_queue_purge() where network interface state change is detected. This is enough to prevent the problem for the whole node preserving original semantics of the code. v2: - do del_timer_sync() if queue is empty after pneigh_queue_purge() v3: - rebase to net tree Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@kernel.org> Cc: Yajun Deng <yajun.deng@linux.dev> Cc: Roopa Prabhu <roopa@nvidia.com> Cc: Christian Brauner <brauner@kernel.org> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com> Cc: Konstantin Khorenko <khorenko@virtuozzo.com> Cc: kernel@openvz.org Cc: devel@openvz.org Investigated-by: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-30net, neigh: introduce interval_probe_time_ms for periodic probeYuwei Wang1-2/+30
commit ed6cd6a17896 ("net, neigh: Set lower cap for neigh_managed_work rearming") fixed a case when DELAY_PROBE_TIME is configured to 0, the processing of the system work queue hog CPU to 100%, and further more we should introduce a new option used by periodic probe Signed-off-by: Yuwei Wang <wangyuweihx@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-06-10net: rename reference+tracking helpersJakub Kicinski1-9/+9
Netdev reference helpers have a dev_ prefix for historic reasons. Renaming the old helpers would be too much churn but we can rename the tracking ones which are relatively recent and should be the default for new code. Rename: dev_hold_track() -> netdev_hold() dev_put_track() -> netdev_put() dev_replace_track() -> netdev_ref_replace() Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-26net, neigh: Set lower cap for neigh_managed_work rearmingDaniel Borkmann1-1/+1
Yuwei reported that plain reuse of DELAY_PROBE_TIME to rearm work queue in neigh_managed_work is problematic if user explicitly configures the DELAY_PROBE_TIME to 0 for a neighbor table. Such misconfig can then hog CPU to 100% processing the system work queue. Instead, set lower interval bound to HZ which is totally sufficient. Yuwei is additionally looking into making the interval separately configurable from DELAY_PROBE_TIME. Reported-by: Yuwei Wang <wangyuweihx@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/netdev/797c3c53-ce1b-9f60-e253-cda615788f4a@iogearbox.net Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://lore.kernel.org/r/3b8c5aa906c52c3a8c995d1b2e8ccf650ea7c716.1653432794.git.daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-05memcg: accounting for objects allocated for new netdeviceVasily Averin1-1/+1
Creating a new netdevice allocates at least ~50Kb of memory for various kernel objects, but only ~5Kb of them are accounted to memcg. As a result, creating an unlimited number of netdevice inside a memcg-limited container does not fall within memcg restrictions, consumes a significant part of the host's memory, can cause global OOM and lead to random kills of host processes. The main consumers of non-accounted memory are: ~10Kb 80+ kernfs nodes ~6Kb ipv6_add_dev() allocations 6Kb __register_sysctl_table() allocations 4Kb neigh_sysctl_register() allocations 4Kb __devinet_sysctl_register() allocations 4Kb __addrconf_sysctl_register() allocations Accounting of these objects allows to increase the share of memcg-related memory up to 60-70% (~38Kb accounted vs ~54Kb total for dummy netdevice on typical VM with default Fedora 35 kernel) and this should be enough to somehow protect the host from misuse inside container. Other related objects are quite small and may not be taken into account to minimize the expected performance degradation. It should be separately mentonied ~300 bytes of percpu allocation of struct ipstats_mib in snmp6_alloc_dev(), on huge multi-cpu nodes it can become the main consumer of memory. This patch does not enables kernfs accounting as it affects other parts of the kernel and should be discussed separately. However, even without kernfs, this patch significantly improves the current situation and allows to take into account more than half of all netdevice allocations. Signed-off-by: Vasily Averin <vvs@openvz.org> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/354a0a5f-9ec3-a25c-3215-304eab2157bc@openvz.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-26net: neigh: use kfree_skb_reason() for __neigh_event_send()Menglong Dong1-3/+3
Replace kfree_skb() used in __neigh_event_send() with kfree_skb_reason(). Following drop reasons are added: SKB_DROP_REASON_NEIGH_FAILED SKB_DROP_REASON_NEIGH_QUEUEFULL SKB_DROP_REASON_NEIGH_DEAD The first two reasons above should be the hot path that skb drops in neighbour subsystem. Reviewed-by: Mengen Sun <mengensun@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-03net, neigh: Do not trigger immediate probes on NUD_FAILED from ↵Daniel Borkmann1-6/+12
neigh_managed_work syzkaller was able to trigger a deadlock for NTF_MANAGED entries [0]: kworker/0:16/14617 is trying to acquire lock: ffffffff8d4dd370 (&tbl->lock){++-.}-{2:2}, at: ___neigh_create+0x9e1/0x2990 net/core/neighbour.c:652 [...] but task is already holding lock: ffffffff8d4dd370 (&tbl->lock){++-.}-{2:2}, at: neigh_managed_work+0x35/0x250 net/core/neighbour.c:1572 The neighbor entry turned to NUD_FAILED state, where __neigh_event_send() triggered an immediate probe as per commit cd28ca0a3dd1 ("neigh: reduce arp latency") via neigh_probe() given table lock was held. One option to fix this situation is to defer the neigh_probe() back to the neigh_timer_handler() similarly as pre cd28ca0a3dd1. For the case of NTF_MANAGED, this deferral is acceptable given this only happens on actual failure state and regular / expected state is NUD_VALID with the entry already present. The fix adds a parameter to __neigh_event_send() in order to communicate whether immediate probe is allowed or disallowed. Existing call-sites of neigh_event_send() default as-is to immediate probe. However, the neigh_managed_work() disables it via use of neigh_event_send_probe(). [0] <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:334 ___neigh_create+0x9e1/0x2990 net/core/neighbour.c:652 ip6_finish_output2+0x1070/0x14f0 net/ipv6/ip6_output.c:123 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline] __ip6_finish_output+0x61e/0xe90 net/ipv6/ip6_output.c:170 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:451 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xa99/0x17f0 net/ipv6/ndisc.c:508 ndisc_send_ns+0x3a9/0x840 net/ipv6/ndisc.c:650 ndisc_solicit+0x2cd/0x4f0 net/ipv6/ndisc.c:742 neigh_probe+0xc2/0x110 net/core/neighbour.c:1040 __neigh_event_send+0x37d/0x1570 net/core/neighbour.c:1201 neigh_event_send include/net/neighbour.h:470 [inline] neigh_managed_work+0x162/0x250 net/core/neighbour.c:1574 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> Fixes: 7482e3841d52 ("net, neigh: Add NTF_MANAGED flag for managed neighbor entries") Reported-by: syzbot+5239d0e1778a500d477a@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Roopa Prabhu <roopa@nvidia.com> Tested-by: syzbot+5239d0e1778a500d477a@syzkaller.appspotmail.com Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20220201193942.5055-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-22proc: remove PDE_DATA() completelyMuchun Song1-3/+3
Remove PDE_DATA() completely and replace it with pde_data(). [akpm@linux-foundation.org: fix naming clash in drivers/nubus/proc.c] [akpm@linux-foundation.org: now fix it properly] Link: https://lkml.kernel.org/r/20211124081956.87711-2-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Alexey Gladkov <gladkov.alexey@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-12net: Enable neighbor sysctls that is save for userns rootxu xin1-4/+0
Inside netns owned by non-init userns, sysctls about ARP/neighbor is currently not visible and configurable. For the attributes these sysctls correspond to, any modifications make effects on the performance of networking(ARP, especilly) only in the scope of netns, which does not affect other netns. Actually, some tools via netlink can modify these attribute. iproute2 is an example. see as follows: $ unshare -ur -n $ cat /proc/sys/net/ipv4/neigh/lo/retrans_time cat: can't open '/proc/sys/net/ipv4/neigh/lo/retrans_time': No such file or directory $ ip ntable show dev lo inet arp_cache dev lo refcnt 1 reachable 19494 base_reachable 30000 retrans 1000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 1000 inet6 ndisc_cache dev lo refcnt 1 reachable 42394 base_reachable 30000 retrans 1000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 0 $ ip ntable change name arp_cache dev <if> retrans 2000 inet arp_cache dev lo refcnt 1 reachable 22917 base_reachable 30000 retrans 2000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 1000 inet6 ndisc_cache dev lo refcnt 1 reachable 35524 base_reachable 30000 retrans 1000 gc_stale 60000 delay_probe 5000 queue 101 app_probes 0 ucast_probes 3 mcast_probes 3 anycast_delay 1000 proxy_delay 800 proxy_queue 64 locktime 0 Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: xu xin <xu.xin16@zte.com.cn> Acked-by: Joanne Koong <joannekoong@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-2/+1
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09net, neigh: clear whole pneigh_entry at alloc timeEric Dumazet1-2/+1
Commit 2c611ad97a82 ("net, neigh: Extend neigh->flags to 32 bit to allow for extensions") enables a new KMSAM warning [1] I think the bug is actually older, because the following intruction only occurred if ndm->ndm_flags had NTF_PROXY set. pn->flags = ndm->ndm_flags; Let's clear all pneigh_entry fields at alloc time. [1] BUG: KMSAN: uninit-value in pneigh_fill_info+0x986/0xb30 net/core/neighbour.c:2593 pneigh_fill_info+0x986/0xb30 net/core/neighbour.c:2593 pneigh_dump_table net/core/neighbour.c:2715 [inline] neigh_dump_info+0x1e3f/0x2c60 net/core/neighbour.c:2832 netlink_dump+0xaca/0x16a0 net/netlink/af_netlink.c:2265 __netlink_dump_start+0xd1c/0xee0 net/netlink/af_netlink.c:2370 netlink_dump_start include/linux/netlink.h:254 [inline] rtnetlink_rcv_msg+0x181b/0x18c0 net/core/rtnetlink.c:5534 netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2491 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5589 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x1095/0x1360 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x16f3/0x1870 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] sock_write_iter+0x594/0x690 net/socket.c:1057 call_write_iter include/linux/fs.h:2162 [inline] new_sync_write fs/read_write.c:503 [inline] vfs_write+0x1318/0x2030 fs/read_write.c:590 ksys_write+0x28c/0x520 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0xdb/0x120 fs/read_write.c:652 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:3251 [inline] slab_alloc mm/slub.c:3259 [inline] __kmalloc+0xc3c/0x12d0 mm/slub.c:4437 kmalloc include/linux/slab.h:595 [inline] pneigh_lookup+0x60f/0xd70 net/core/neighbour.c:766 arp_req_set_public net/ipv4/arp.c:1016 [inline] arp_req_set+0x430/0x10a0 net/ipv4/arp.c:1032 arp_ioctl+0x8d4/0xb60 net/ipv4/arp.c:1232 inet_ioctl+0x4ef/0x820 net/ipv4/af_inet.c:947 sock_do_ioctl net/socket.c:1118 [inline] sock_ioctl+0xa3f/0x13e0 net/socket.c:1235 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0x2df/0x4a0 fs/ioctl.c:860 __x64_sys_ioctl+0xd8/0x110 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae CPU: 1 PID: 20001 Comm: syz-executor.0 Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 62dd93181aaa ("[IPV6] NDISC: Set per-entry is_router flag in Proxy NA.") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Roopa Prabhu <roopa@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20211206165329.1049835-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07net: add net device refcount tracker to struct neigh_parmsEric Dumazet1-3/+3
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07net: add net device refcount tracker to struct pneigh_entryEric Dumazet1-4/+4
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07net: add net device refcount tracker to struct neighbourEric Dumazet1-2/+2
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-22net, neigh: Fix crash in v6 module initialization error pathDaniel Borkmann1-0/+1
When IPv6 module gets initialized, but it's hitting an error in inet6_init() where it then needs to undo all the prior initialization work, it also might do a call to ndisc_cleanup() which then calls neigh_table_clear(). In there is a missing timer cancellation of the table's managed_work item. The kernel test robot explicitly triggered this error path and caused a UAF crash similar to the below: [...] [ 28.833183][ C0] BUG: unable to handle page fault for address: f7a43288 [ 28.833973][ C0] #PF: supervisor write access in kernel mode [ 28.834660][ C0] #PF: error_code(0x0002) - not-present page [ 28.835319][ C0] *pde = 06b2c067 *pte = 00000000 [ 28.835853][ C0] Oops: 0002 [#1] PREEMPT [ 28.836367][ C0] CPU: 0 PID: 303 Comm: sed Not tainted 5.16.0-rc1-00233-g83ff5faa0d3b #7 [ 28.837293][ C0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1 04/01/2014 [ 28.838338][ C0] EIP: __run_timers.constprop.0+0x82/0x440 [...] [ 28.845607][ C0] Call Trace: [ 28.845942][ C0] <SOFTIRQ> [ 28.846333][ C0] ? check_preemption_disabled.isra.0+0x2a/0x80 [ 28.846975][ C0] ? __this_cpu_preempt_check+0x8/0xa [ 28.847570][ C0] run_timer_softirq+0xd/0x40 [ 28.848050][ C0] __do_softirq+0xf5/0x576 [ 28.848547][ C0] ? __softirqentry_text_start+0x10/0x10 [ 28.849127][ C0] do_softirq_own_stack+0x2b/0x40 [ 28.849749][ C0] </SOFTIRQ> [ 28.850087][ C0] irq_exit_rcu+0x7d/0xc0 [ 28.850587][ C0] common_interrupt+0x2a/0x40 [ 28.851068][ C0] asm_common_interrupt+0x119/0x120 [...] Note that IPv6 module cannot be unloaded as per 8ce440610357 ("ipv6: do not allow ipv6 module to be removed") hence this can only be seen during module initialization error. Tested with kernel test robot's reproducer. Fixes: 7482e3841d52 ("net, neigh: Add NTF_MANAGED flag for managed neighbor entries") Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Li Zhijian <zhijianx.li@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-15net, neigh: Reject creating NUD_PERMANENT with NTF_MANAGED entriesDaniel Borkmann1-3/+8
The combination of NUD_PERMANENT + NTF_MANAGED is not supported and does not make sense either given the former indicates a static/fixed neighbor entry whereas the latter a dynamically resolved one. While it is possible to transition from one over to the other, we should however reject such creation attempts. Fixes: 7482e3841d52 ("net, neigh: Add NTF_MANAGED flag for managed neighbor entries") Suggested-by: David Ahern <dsahern@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-15net, neigh: Use NLA_POLICY_MASK helper for NDA_FLAGS_EXT attributeDaniel Borkmann1-5/+1
Instead of open-coding a check for invalid bits in NTF_EXT_MASK, we can just use the NLA_POLICY_MASK() helper instead, and simplify NDA_FLAGS_EXT sanity check this way. Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-15net, neigh: Add build-time assertion to avoid neigh->flags overflowDaniel Borkmann1-0/+3
Currently, NDA_FLAGS_EXT flags allow a maximum of 24 bits to be used for extended neighbor flags. These are eventually fed into neigh->flags by shifting with NTF_EXT_SHIFT as per commit 2c611ad97a82 ("net, neigh: Extend neigh->flags to 32 bit to allow for extensions"). If really ever needed in future, the full 32 bits from NDA_FLAGS_EXT can be used, it would only require to move neigh->flags from u32 to u64 inside the kernel. Add a build-time assertion such that when extending the NTF_EXT_MASK with new bits, we'll trigger an error once we surpass the 24th bit. This assumes that no bit holes in new NTF_EXT_* flags will slip in from UAPI, but I think this is reasonable to assume. Suggested-by: David Ahern <dsahern@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12net, neigh: Add NTF_MANAGED flag for managed neighbor entriesDaniel Borkmann1-30/+83
Allow a user space control plane to insert entries with a new NTF_EXT_MANAGED flag. The flag then indicates to the kernel that the neighbor entry should be periodically probed for keeping the entry in NUD_REACHABLE state iff possible. The use case for this is targeting XDP or tc BPF load-balancers which use the bpf_fib_lookup() BPF helper in order to piggyback on neighbor resolution for their backends. Given they cannot be resolved in fast-path, a control plane inserts the L3 (without L2) entries manually into the neighbor table and lets the kernel do the neighbor resolution either on the gateway or on the backend directly in case the latter resides in the same L2. This avoids to deal with L2 in the control plane and to rebuild what the kernel already does best anyway. NTF_EXT_MANAGED can be combined with NTF_EXT_LEARNED in order to avoid GC eviction. The kernel then adds NTF_MANAGED flagged entries to a per-neighbor table which gets triggered by the system work queue to periodically call neigh_event_send() for performing the resolution. The implementation allows migration from/to NTF_MANAGED neighbor entries, so that already existing entries can be converted by the control plane if needed. Potentially, we could make the interval for periodically calling neigh_event_send() configurable; right now it's set to DELAY_PROBE_TIME which is also in line with mlxsw which has similar driver-internal infrastructure c723c735fa6b ("mlxsw: spectrum_router: Periodically update the kernel's neigh table"). In future, the latter could possibly reuse the NTF_MANAGED neighbors as well. Example: # ./ip/ip n replace 192.168.178.30 dev enp5s0 managed extern_learn # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a managed extern_learn REACHABLE [...] Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Roopa Prabhu <roopa@nvidia.com> Link: https://linuxplumbersconf.org/event/11/contributions/953/ Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12net, neigh: Extend neigh->flags to 32 bit to allow for extensionsRoopa Prabhu1-15/+40
Currently, all bits in struct ndmsg's ndm_flags are used up with the most recent addition of 435f2e7cc0b7 ("net: bridge: add support for sticky fdb entries"). This makes it impossible to extend the neighboring subsystem with new NTF_* flags: struct ndmsg { __u8 ndm_family; __u8 ndm_pad1; __u16 ndm_pad2; __s32 ndm_ifindex; __u16 ndm_state; __u8 ndm_flags; __u8 ndm_type; }; There are ndm_pad{1,2} attributes which are not used. However, due to uncareful design, the kernel does not enforce them to be zero upon new neighbor entry addition, and given they've been around forever, it is not possible to reuse them today due to risk of breakage. One option to overcome this limitation is to add a new NDA_FLAGS_EXT attribute for extended flags. In struct neighbour, there is a 3 byte hole between protocol and ha_lock, which allows neigh->flags to be extended from 8 to 32 bits while still being on the same cacheline as before. This also allows for all future NTF_* flags being in neigh->flags rather than yet another flags field. Unknown flags in NDA_FLAGS_EXT will be rejected by the kernel. Co-developed-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Roopa Prabhu <roopa@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12net, neigh: Enable state migration between NUD_PERMANENT and NTF_USEDaniel Borkmann1-9/+13
Currently, it is not possible to migrate a neighbor entry between NUD_PERMANENT state and NTF_USE flag with a dynamic NUD state from a user space control plane. Similarly, it is not possible to add/remove NTF_EXT_LEARNED flag from an existing neighbor entry in combination with NTF_USE flag. This is due to the latter directly calling into neigh_event_send() without any meta data updates as happening in __neigh_update(). Thus, to enable this use case, extend the latter with a NEIGH_UPDATE_F_USE flag where we break the NUD_PERMANENT state in particular so that a latter neigh_event_send() is able to re-resolve a neighbor entry. Before fix, NUD_PERMANENT -> NUD_* & NTF_USE: # ./ip/ip n replace 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT [...] # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT [...] As can be seen, despite the admin-triggered replace, the entry remains in the NUD_PERMANENT state. After fix, NUD_PERMANENT -> NUD_* & NTF_USE: # ./ip/ip n replace 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT [...] # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn REACHABLE [...] # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn STALE [...] # ./ip/ip n replace 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT [...] After the fix, the admin-triggered replace switches to a dynamic state from the NTF_USE flag which triggered a new neighbor resolution. Likewise, we can transition back from there, if needed, into NUD_PERMANENT. Similar before/after behavior can be observed for below transitions: Before fix, NTF_USE -> NTF_USE | NTF_EXT_LEARNED -> NTF_USE: # ./ip/ip n replace 192.168.178.30 dev enp5s0 use # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE [...] # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE [...] After fix, NTF_USE -> NTF_USE | NTF_EXT_LEARNED -> NTF_USE: # ./ip/ip n replace 192.168.178.30 dev enp5s0 use # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE [...] # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn REACHABLE [...] # ./ip/ip n replace 192.168.178.30 dev enp5s0 use # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE [..] Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Roopa Prabhu <roopa@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12net, neigh: Fix NTF_EXT_LEARNED in combination with NTF_USEDaniel Borkmann1-12/+14
The NTF_EXT_LEARNED neigh flag is usually propagated back to user space upon dump of the neighbor table. However, when used in combination with NTF_USE flag this is not the case despite exempting the entry from the garbage collector. This results in inconsistent state since entries are typically marked in neigh->flags with NTF_EXT_LEARNED, but here they are not. Fix it by propagating the creation flag to ___neigh_create(). Before fix: # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE [...] After fix: # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn # ./ip/ip n 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn REACHABLE [...] Fixes: 9ce33e46531d ("neighbour: support for NTF_EXT_LEARNED flag") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Roopa Prabhu <roopa@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11net: Support filtering interfaces on no masterLahav Schlesinger1-0/+7
Currently there's support for filtering neighbours/links for interfaces which have a specific master device (using the IFLA_MASTER/NDA_MASTER attributes). This patch adds support for filtering interfaces/neighbours dump for interfaces that *don't* have a master. Signed-off-by: Lahav Schlesinger <lschlesinger@drivenets.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20210810090658.2778960-1-lschlesinger@drivenets.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-05net: Remove redundant if statementsYajun Deng1-10/+5
The 'if (dev)' statement already move into dev_{put , hold}, so remove redundant if statements. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03net: Keep vertical alignmentYajun Deng1-3/+4
Those files under /proc/net/stat/ don't have vertical alignment, it looks very difficult. Modify the seq_printf statement, keep vertical alignment. v2: - Use seq_puts() and seq_printf() correctly. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+1
Trivial conflicts in net/can/isotp.c and tools/testing/selftests/net/mptcp/mptcp_connect.sh scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c to include/linux/ptp_clock_kernel.h in -next so re-apply the fix there. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-08neighbour: allow NUD_NOARP entries to be forced GCedDavid Ahern1-0/+1
IFF_POINTOPOINT interfaces use NUD_NOARP entries for IPv6. It's possible to fill up the neighbour table with enough entries that it will overflow for valid connections after that. This behaviour is more prevalent after commit 58956317c8de ("neighbor: Improve garbage collection") is applied, as it prevents removal from entries that are not NUD_FAILED, unless they are more than 5s old. Fixes: 58956317c8de (neighbor: Improve garbage collection) Reported-by: Kasper Dupont <kasperd@gjkwv.06.feb.2021.kasperd.net> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-11neighbour: Remove redundant initialization of 'bucket'Yang Li1-1/+1
Integer variable 'bucket' is being initialized however this value is never read as 'bucket' is assigned zero in for statement. Remove the redundant assignment. Cleans up clang warning: net/core/neighbour.c:3144:6: warning: Value stored to 'bucket' during its initialization is never read [clang-analyzer-deadcode.DeadStores] Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-22neighbour: Prevent Race condition in neighbour subsytemChinmay Agarwal1-0/+4
Following Race Condition was detected: <CPU A, t0>: Executing: __netif_receive_skb() ->__netif_receive_skb_core() -> arp_rcv() -> arp_process().arp_process() calls __neigh_lookup() which takes a reference on neighbour entry 'n'. Moves further along, arp_process() and calls neigh_update()-> __neigh_update(). Neighbour entry is unlocked just before a call to neigh_update_gc_list. This unlocking paves way for another thread that may take a reference on the same and mark it dead and remove it from gc_list. <CPU B, t1> - neigh_flush_dev() is under execution and calls neigh_mark_dead(n) marking the neighbour entry 'n' as dead. Also n will be removed from gc_list. Moves further along neigh_flush_dev() and calls neigh_cleanup_and_release(n), but since reference count increased in t1, 'n' couldn't be destroyed. <CPU A, t3>- Code hits neigh_update_gc_list, with neighbour entry set as dead. <CPU A, t4> - arp_process() finally calls neigh_release(n), destroying the neighbour entry and we have a destroyed ntry still part of gc_list. Fixes: eb4e8fac00d1("neighbour: Prevent a dead entry from updating gc_list") Signed-off-by: Chinmay Agarwal <chinagar@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-01neighbour: Disregard DEAD dst in neigh_updateTong Zhu1-1/+1
After a short network outage, the dst_entry is timed out and put in DST_OBSOLETE_DEAD. We are in this code because arp reply comes from this neighbour after network recovers. There is a potential race condition that dst_entry is still in DST_OBSOLETE_DEAD. With that, another neighbour lookup causes more harm than good. In best case all packets in arp_queue are lost. This is counterproductive to the original goal of finding a better path for those packets. I observed a worst case with 4.x kernel where a dst_entry in DST_OBSOLETE_DEAD state is associated with loopback net_device. It leads to an ethernet header with all zero addresses. A packet with all zero source MAC address is quite deadly with mac80211, ath9k and 802.11 block ack. It fails ieee80211_find_sta_by_ifaddr in ath9k (xmit.c). Ath9k flushes tx queue (ath_tx_complete_aggr). BAW (block ack window) is not updated. BAW logic is damaged and ath9k transmission is disabled. Signed-off-by: Tong Zhu <zhutong@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-3/+4
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-30neighbour: Prevent a dead entry from updating gc_listChinmay Agarwal1-3/+4
Following race condition was detected: <CPU A, t0> - neigh_flush_dev() is under execution and calls neigh_mark_dead(n) marking the neighbour entry 'n' as dead. <CPU B, t1> - Executing: __netif_receive_skb() -> __netif_receive_skb_core() -> arp_rcv() -> arp_process().arp_process() calls __neigh_lookup() which takes a reference on neighbour entry 'n'. <CPU A, t2> - Moves further along neigh_flush_dev() and calls neigh_cleanup_and_release(n), but since reference count increased in t2, 'n' couldn't be destroyed. <CPU B, t3> - Moves further along, arp_process() and calls neigh_update()-> __neigh_update() -> neigh_update_gc_list(), which adds the neighbour entry back in gc_list(neigh_mark_dead(), removed it earlier in t0 from gc_list) <CPU B, t4> - arp_process() finally calls neigh_release(n), destroying the neighbour entry. This leads to 'n' still being part of gc_list, but the actual neighbour structure has been freed. The situation can be prevented from happening if we disallow a dead entry to have any possibility of updating gc_list. This is what the patch intends to achieve. Fixes: 9c29a2f55ec0 ("neighbor: Fix locking order for gc_list changes") Signed-off-by: Chinmay Agarwal <chinagar@codeaurora.org> Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20210127165453.GA20514@chinagar-linux.qualcomm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-16neighbor: remove definition of DEBUGTom Rix1-1/+0
Defining DEBUG should only be done in development. So remove DEBUG. Signed-off-by: Tom Rix <trix@redhat.com> Link: https://lore.kernel.org/r/20210114212917.48174-1-trix@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-29net: neighbor: fix a crash caused by mod zeroweichenchen1-4/+2
pneigh_enqueue() tries to obtain a random delay by mod NEIGH_VAR(p, PROXY_DELAY). However, NEIGH_VAR(p, PROXY_DELAY) migth be zero at that point because someone could write zero to /proc/sys/net/ipv4/neigh/[device]/proxy_delay after the callers check it. This patch uses prandom_u32_max() to get a random delay instead which avoids potential division by zero. Signed-off-by: weichenchen <weichen.chen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-11-14net: Exempt multicast addresses from five-second neighbor lifetimeJeff Dike1-0/+2
Commit 58956317c8de ("neighbor: Improve garbage collection") guarantees neighbour table entries a five-second lifetime. Processes which make heavy use of multicast can fill the neighour table with multicast addresses in five seconds. At that point, neighbour entries can't be GC-ed because they aren't five seconds old yet, the kernel log starts to fill up with "neighbor table overflow!" messages, and sends start to fail. This patch allows multicast addresses to be thrown out before they've lived out their five seconds. This makes room for non-multicast addresses and makes messages to all addresses more reliable in these circumstances. Fixes: 58956317c8de ("neighbor: Improve garbage collection") Signed-off-by: Jeff Dike <jdike@akamai.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20201113015815.31397-1-jdike@akamai.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-06-25net: neighbor: add fdb extended attributeNikolay Aleksandrov1-0/+1
Add an attribute to NDA which will contain all future fdb-specific attributes in order to avoid polluting the NDA namespace with e.g. bridge or vxlan specific attributes. The attribute is called NDA_FDB_EXT_ATTRS and the structure would look like: [NDA_FDB_EXT_ATTRS] = { [NFEA_xxx] } Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-2/+2
xdp_umem.c had overlapping changes between the 64-bit math fix for the calculation of npgs and the removal of the zerocopy memory type which got rid of the chunk_size_nohdr member. The mlx5 Kconfig conflict is a case where we just take the net-next copy of the Kconfig entry dependency as it takes on the ESWITCH dependency by one level of indirection which is what the 'net' conflicting change is trying to ensure. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-30neigh: fix ARP retransmit timer guardHangbin Liu1-2/+2
In commit 19e16d220f0a ("neigh: support smaller retrans_time settting") we add more accurate control for ARP and NS. But for ARP I forgot to update the latest guard in neigh_timer_handler(), then the next retransmit would be reset to jiffies + HZ/2 if we set the retrans_time less than 500ms. Fix it by setting the time_before() check to HZ/100. IPv6 does not have this issue. Reported-by: Jianwen Ji <jiji@redhat.com> Fixes: 19e16d220f0a ("neigh: support smaller retrans_time settting") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-23vxlan: ecmp support for mac fdb entriesRoopa Prabhu1-0/+2
Todays vxlan mac fdb entries can point to multiple remote ips (rdsts) with the sole purpose of replicating broadcast-multicast and unknown unicast packets to those remote ips. E-VPN multihoming [1,2,3] requires bridged vxlan traffic to be load balanced to remote switches (vteps) belonging to the same multi-homed ethernet segment (E-VPN multihoming is analogous to multi-homed LAG implementations, but with the inter-switch peerlink replaced with a vxlan tunnel). In other words it needs support for mac ecmp. Furthermore, for faster convergence, E-VPN multihoming needs the ability to update fdb ecmp nexthops independent of the fdb entries. New route nexthop API is perfect for this usecase. This patch extends the vxlan fdb code to take a nexthop id pointing to an ecmp nexthop group. Changes include: - New NDA_NH_ID attribute for fdbs - Use the newly added fdb nexthop groups - makes vxlan rdsts and nexthop handling code mutually exclusive - since this is a new use-case and the requirement is for ecmp nexthop groups, the fdb add and update path checks that the nexthop is really an ecmp nexthop group. This check can be relaxed in the future, if we want to introduce replication fdb nexthop groups and allow its use in lieu of current rdst lists. - fdb update requests with nexthop id's only allowed for existing fdb's that have nexthop id's - learning will not override an existing fdb entry with nexthop group - I have wrapped the switchdev offload code around the presence of rdst [1] E-VPN RFC https://tools.ietf.org/html/rfc7432 [2] E-VPN with vxlan https://tools.ietf.org/html/rfc8365 [3] http://vger.kernel.org/lpc_net2018_talks/scaling_bridge_fdb_database_slidesV3.pdf Includes a null check fix in vxlan_xmit from Nikolay v2 - Fixed build issue: Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-3/+3
Conflicts were all overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-05neigh: send protocol value in neighbor create notificationRoman Mashak1-3/+3
When a new neighbor entry has been added, event is generated but it does not include protocol, because its value is assigned after the event notification routine has run, so move protocol assignment code earlier. Fixes: df9b0e30d44c ("neighbor: Add protocol attribute") Cc: David Ahern <dsahern@gmail.com> Signed-off-by: Roman Mashak <mrv@mojatatu.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig1-15/+13
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-03neigh: support smaller retrans_time setttingHangbin Liu1-4/+6
Currently, we limited the retrans_time to be greater than HZ/2. i.e. setting retrans_time less than 500ms will not work. This makes the user unable to achieve a more accurate control for bonding arp fast failover. Update the sanity check to HZ/100, which is 10ms, to let users have more ability on the retrans_time control. v3: sync the behavior with IPv6 and update all the timer handler v2: use HZ instead of hard code number Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-20net: neigh: remove unused NEIGH_SYSCTL_MS_JIFFIES_ENTRYLi RongQing1-3/+0
this macro is never used, so remove it Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24neigh_stat_seq_next() should increase position indexVasily Averin1-0/+1
if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>