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2024-06-12net: give more chances to rcu in netdev_wait_allrefs_any()Eric Dumazet1-1/+2
[ Upstream commit cd42ba1c8ac9deb9032add6adf491110e7442040 ] This came while reviewing commit c4e86b4363ac ("net: add two more call_rcu_hurry()"). Paolo asked if adding one synchronize_rcu() would help. While synchronize_rcu() does not help, making sure to call rcu_barrier() before msleep(wait) is definitely helping to make sure lazy call_rcu() are completed. Instead of waiting ~100 seconds in my tests, the ref_tracker splats occurs one time only, and netdev_wait_allrefs_any() latency is reduced to the strict minimum. Ideally we should audit our call_rcu() users to make sure no refcount (or cascading call_rcu()) is held too long, because rcu_barrier() is quite expensive. Fixes: 0e4be9e57e8c ("net: use exponential backoff in netdev_wait_allrefs") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/all/28bbf698-befb-42f6-b561-851c67f464aa@kernel.org/T/#m76d73ed6b03cd930778ac4d20a777f22a08d6824 Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-27net: report RCU QS on threaded NAPI repollingYan Zhai1-0/+3
[ Upstream commit d6dbbb11247c71203785a2c9da474c36f4b19eae ] NAPI threads can keep polling packets under load. Currently it is only calling cond_resched() before repolling, but it is not sufficient to clear out the holdout of RCU tasks, which prevent BPF tracing programs from detaching for long period. This can be reproduced easily with following set up: ip netns add test1 ip netns add test2 ip -n test1 link add veth1 type veth peer name veth2 netns test2 ip -n test1 link set veth1 up ip -n test1 link set lo up ip -n test2 link set veth2 up ip -n test2 link set lo up ip -n test1 addr add 192.168.1.2/31 dev veth1 ip -n test1 addr add 1.1.1.1/32 dev lo ip -n test2 addr add 192.168.1.3/31 dev veth2 ip -n test2 addr add 2.2.2.2/31 dev lo ip -n test1 route add default via 192.168.1.3 ip -n test2 route add default via 192.168.1.2 for i in `seq 10 210`; do for j in `seq 10 210`; do ip netns exec test2 iptables -I INPUT -s 3.3.$i.$j -p udp --dport 5201 done done ip netns exec test2 ethtool -K veth2 gro on ip netns exec test2 bash -c 'echo 1 > /sys/class/net/veth2/threaded' ip netns exec test1 ethtool -K veth1 tso off Then run an iperf3 client/server and a bpftrace script can trigger it: ip netns exec test2 iperf3 -s -B 2.2.2.2 >/dev/null& ip netns exec test1 iperf3 -c 2.2.2.2 -B 1.1.1.1 -u -l 1500 -b 3g -t 100 >/dev/null& bpftrace -e 'kfunc:__napi_poll{@=count();} interval:s:1{exit();}' Report RCU quiescent states periodically will resolve the issue. Fixes: 29863d41bb6e ("net: implement threaded-able napi poll loop support") Reviewed-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Link: https://lore.kernel.org/r/4c3b0d3f32d3b18949d75b18e5e1d9f13a24f025.1710877680.git.yan@cloudflare.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-27packet: annotate data-races around ignore_outgoingEric Dumazet1-1/+1
[ Upstream commit 6ebfad33161afacb3e1e59ed1c2feefef70f9f97 ] ignore_outgoing is read locklessly from dev_queue_xmit_nit() and packet_getsockopt() Add appropriate READ_ONCE()/WRITE_ONCE() annotations. syzbot reported: BUG: KCSAN: data-race in dev_queue_xmit_nit / packet_setsockopt write to 0xffff888107804542 of 1 bytes by task 22618 on cpu 0: packet_setsockopt+0xd83/0xfd0 net/packet/af_packet.c:4003 do_sock_setsockopt net/socket.c:2311 [inline] __sys_setsockopt+0x1d8/0x250 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0x66/0x80 net/socket.c:2340 do_syscall_64+0xd3/0x1d0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 read to 0xffff888107804542 of 1 bytes by task 27 on cpu 1: dev_queue_xmit_nit+0x82/0x620 net/core/dev.c:2248 xmit_one net/core/dev.c:3527 [inline] dev_hard_start_xmit+0xcc/0x3f0 net/core/dev.c:3547 __dev_queue_xmit+0xf24/0x1dd0 net/core/dev.c:4335 dev_queue_xmit include/linux/netdevice.h:3091 [inline] batadv_send_skb_packet+0x264/0x300 net/batman-adv/send.c:108 batadv_send_broadcast_skb+0x24/0x30 net/batman-adv/send.c:127 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:392 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x3f0/0x4b0 net/batman-adv/bat_iv_ogm.c:1700 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335 worker_thread+0x526/0x730 kernel/workqueue.c:3416 kthread+0x1d1/0x210 kernel/kthread.c:388 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 value changed: 0x00 -> 0x01 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 27 Comm: kworker/u8:1 Tainted: G W 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Fixes: fa788d986a3a ("packet: add sockopt to ignore outgoing packets") Reported-by: syzbot+c669c1136495a2e7c31f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/CANn89i+Z7MfbkBLOv=p7KZ7=K1rKHO4P1OL5LYDCtBiyqsa9oQ@mail.gmail.com/T/#t Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01net: dev: Convert sa_data to flexible array in struct sockaddrKees Cook1-1/+1
[ Upstream commit b5f0de6df6dce8d641ef58ef7012f3304dffb9a1 ] One of the worst offenders of "fake flexible arrays" is struct sockaddr, as it is the classic example of why GCC and Clang have been traditionally forced to treat all trailing arrays as fake flexible arrays: in the distant misty past, sa_data became too small, and code started just treating it as a flexible array, even though it was fixed-size. The special case by the compiler is specifically that sizeof(sa->sa_data) and FORTIFY_SOURCE (which uses __builtin_object_size(sa->sa_data, 1)) do not agree (14 and -1 respectively), which makes FORTIFY_SOURCE treat it as a flexible array. However, the coming -fstrict-flex-arrays compiler flag will remove these special cases so that FORTIFY_SOURCE can gain coverage over all the trailing arrays in the kernel that are _not_ supposed to be treated as a flexible array. To deal with this change, convert sa_data to a true flexible array. To keep the structure size the same, move sa_data into a union with a newly introduced sa_data_min with the original size. The result is that FORTIFY_SOURCE can continue to have no idea how large sa_data may actually be, but anything using sizeof(sa->sa_data) must switch to sizeof(sa->sa_data_min). Cc: Jens Axboe <axboe@kernel.dk> Cc: Pavel Begunkov <asml.silence@gmail.com> Cc: David Ahern <dsahern@kernel.org> Cc: Dylan Yudaken <dylany@fb.com> Cc: Yajun Deng <yajun.deng@linux.dev> Cc: Petr Machata <petrm@nvidia.com> Cc: Hangbin Liu <liuhangbin@gmail.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: syzbot <syzkaller@googlegroups.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221018095503.never.671-kees@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Stable-dep-of: a7d6027790ac ("arp: Prevent overflow in arp_req_get().") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-01net: fix removing a namespace with conflicting altnamesJakub Kicinski1-0/+9
[ Upstream commit d09486a04f5da0a812c26217213b89a3b1acf836 ] Mark reports a BUG() when a net namespace is removed. kernel BUG at net/core/dev.c:11520! Physical interfaces moved outside of init_net get "refunded" to init_net when that namespace disappears. The main interface name may get overwritten in the process if it would have conflicted. We need to also discard all conflicting altnames. Recent fixes addressed ensuring that altnames get moved with the main interface, which surfaced this problem. Reported-by: Марк Коренберг <socketpair@gmail.com> Link: https://lore.kernel.org/all/CAEmTpZFZ4Sv3KwqFOY2WKDHeZYdi0O7N5H1nTvcGp=SAEavtDg@mail.gmail.com/ Fixes: 7663d522099e ("net: check for altname conflicts when changing netdev's netns") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-01net: check dev->gso_max_size in gso_features_check()Eric Dumazet1-0/+3
[ Upstream commit 24ab059d2ebd62fdccc43794796f6ffbabe49ebc ] Some drivers might misbehave if TSO packets get too big. GVE for instance uses a 16bit field in its TX descriptor, and will do bad things if a packet is bigger than 2^16 bytes. Linux TCP stack honors dev->gso_max_size, but there are other ways for too big packets to reach an ndo_start_xmit() handler : virtio_net, af_packet, GRO... Add a generic check in gso_features_check() and fallback to GSO when needed. gso_max_size was added in the blamed commit. Fixes: 82cc1a7a5687 ("[NET]: Add per-connection option to set max TSO frame size") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20231219125331.4127498-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25net: move altnames together with the netdeviceJakub Kicinski1-4/+9
commit 8e15aee621618a3ee3abecaf1fd8c1428098b7ef upstream. The altname nodes are currently not moved to the new netns when netdevice itself moves: [ ~]# ip netns add test [ ~]# ip -netns test link add name eth0 type dummy [ ~]# ip -netns test link property add dev eth0 altname some-name [ ~]# ip -netns test link show dev some-name 2: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 1e:67:ed:19:3d:24 brd ff:ff:ff:ff:ff:ff altname some-name [ ~]# ip -netns test link set dev eth0 netns 1 [ ~]# ip link ... 3: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 02:40:88:62:ec:b8 brd ff:ff:ff:ff:ff:ff altname some-name [ ~]# ip li show dev some-name Device "some-name" does not exist. Remove them from the hash table when device is unlisted and add back when listed again. Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25net: check for altname conflicts when changing netdev's netnsJakub Kicinski1-1/+8
commit 7663d522099ecc464512164e660bc771b2ff7b64 upstream. It's currently possible to create an altname conflicting with an altname or real name of another device by creating it in another netns and moving it over: [ ~]$ ip link add dev eth0 type dummy [ ~]$ ip netns add test [ ~]$ ip -netns test link add dev ethX netns test type dummy [ ~]$ ip -netns test link property add dev ethX altname eth0 [ ~]$ ip -netns test link set dev ethX netns 1 [ ~]$ ip link ... 3: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 02:40:88:62:ec:b8 brd ff:ff:ff:ff:ff:ff ... 5: ethX: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 26:b7:28:78:38:0f brd ff:ff:ff:ff:ff:ff altname eth0 Create a macro for walking the altnames, this hopefully makes it clearer that the list we walk contains only altnames. Which is otherwise not entirely intuitive. Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25net: fix ifname in netlink ntf during netns moveJakub Kicinski1-13/+31
commit 311cca40661f428b7aa114fb5af578cfdbe3e8b6 upstream. dev_get_valid_name() overwrites the netdev's name on success. This makes it hard to use in prepare-commit-like fashion, where we do validation first, and "commit" to the change later. Factor out a helper which lets us save the new name to a buffer. Use it to fix the problem of notification on netns move having incorrect name: 5: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default link/ether be:4d:58:f9:d5:40 brd ff:ff:ff:ff:ff:ff 6: eth1: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default link/ether 1e:4a:34:36:e3:cd brd ff:ff:ff:ff:ff:ff [ ~]# ip link set dev eth0 netns 1 name eth1 ip monitor inside netns: Deleted inet eth0 Deleted inet6 eth0 Deleted 5: eth1: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default link/ether be:4d:58:f9:d5:40 brd ff:ff:ff:ff:ff:ff new-netnsid 0 new-ifindex 7 Name is reported as eth1 in old netns for ifindex 5, already renamed. Fixes: d90310243fd7 ("net: device name allocation cleanups") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25net: avoid UAF on deleted altnameJakub Kicinski1-1/+6
commit 1a83f4a7c156fa6bbd6b530e89fa3270bf3d9d1b upstream. Altnames are accessed under RCU (dev_get_by_name_rcu()) but freed by kfree() with no synchronization point. Each node has one or two allocations (node and a variable-size name, sometimes the name is netdev->name). Adding rcu_heads here is a bit tedious. Besides most code which unlists the names already has rcu barriers - so take the simpler approach of adding synchronize_rcu(). Note that the one on the unregistration path (which matters more) is removed by the next fix. Fixes: ff92741270bf ("net: introduce name_node struct to be used in hashlist") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-20net: refine debug info in skb_checksum_help()Eric Dumazet1-2/+6
[ Upstream commit 26c29961b142444cd99361644c30fa1e9b3da6be ] syzbot uses panic_on_warn. This means that the skb_dump() I added in the blamed commit are not even called. Rewrite this so that we get the needed skb dump before syzbot crashes. Fixes: eeee4b77dc52 ("net: add more debug info in skb_checksum_help()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20231006173355.2254983-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-14net: sched: add rcu annotations around qdisc->qdisc_sleepingEric Dumazet1-1/+1
[ Upstream commit d636fc5dd692c8f4e00ae6e0359c0eceeb5d9bdb ] syzbot reported a race around qdisc->qdisc_sleeping [1] It is time we add proper annotations to reads and writes to/from qdisc->qdisc_sleeping. [1] BUG: KCSAN: data-race in dev_graft_qdisc / qdisc_lookup_rcu read to 0xffff8881286fc618 of 8 bytes by task 6928 on cpu 1: qdisc_lookup_rcu+0x192/0x2c0 net/sched/sch_api.c:331 __tcf_qdisc_find+0x74/0x3c0 net/sched/cls_api.c:1174 tc_get_tfilter+0x18f/0x990 net/sched/cls_api.c:2547 rtnetlink_rcv_msg+0x7af/0x8c0 net/core/rtnetlink.c:6386 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2546 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6413 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1913 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x375/0x4c0 net/socket.c:2503 ___sys_sendmsg net/socket.c:2557 [inline] __sys_sendmsg+0x1e3/0x270 net/socket.c:2586 __do_sys_sendmsg net/socket.c:2595 [inline] __se_sys_sendmsg net/socket.c:2593 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2593 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd write to 0xffff8881286fc618 of 8 bytes by task 6912 on cpu 0: dev_graft_qdisc+0x4f/0x80 net/sched/sch_generic.c:1115 qdisc_graft+0x7d0/0xb60 net/sched/sch_api.c:1103 tc_modify_qdisc+0x712/0xf10 net/sched/sch_api.c:1693 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6395 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2546 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6413 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1913 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x375/0x4c0 net/socket.c:2503 ___sys_sendmsg net/socket.c:2557 [inline] __sys_sendmsg+0x1e3/0x270 net/socket.c:2586 __do_sys_sendmsg net/socket.c:2595 [inline] __se_sys_sendmsg net/socket.c:2593 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2593 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 6912 Comm: syz-executor.5 Not tainted 6.4.0-rc3-syzkaller-00190-g0d85b27b0cc6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023 Fixes: 3a7d0d07a386 ("net: sched: extend Qdisc with rcu") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Vlad Buslov <vladbu@nvidia.com> Acked-by: Jamal Hadi Salim<jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-14rfs: annotate lockless accesses to RFS sock flow tableEric Dumazet1-2/+4
[ Upstream commit 5c3b74a92aa285a3df722bf6329ba7ccf70346d6 ] Add READ_ONCE()/WRITE_ONCE() on accesses to the sock flow table. This also prevents a (smart ?) compiler to remove the condition in: if (table->ents[index] != newval) table->ents[index] = newval; We need the condition to avoid dirtying a shared cache line. Fixes: fec5e652e58f ("rfs: Receive Flow Steering") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-24net: Catch invalid index in XPS mappingNick Child1-0/+2
[ Upstream commit 5dd0dfd55baec0742ba8f5625a0dd064aca7db16 ] When setting the XPS value of a TX queue, warn the user once if the index of the queue is greater than the number of allocated TX queues. Previously, this scenario went uncaught. In the best case, it resulted in unnecessary allocations. In the worst case, it resulted in out-of-bounds memory references through calls to `netdev_get_tx_queue( dev, index)`. Therefore, it is important to inform the user but not worth returning an error and risk downing the netdevice. Signed-off-by: Nick Child <nnac123@linux.ibm.com> Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com> Link: https://lore.kernel.org/r/20230321150725.127229-1-nnac123@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-24net: add vlan_get_protocol_and_depth() helperEric Dumazet1-1/+1
[ Upstream commit 4063384ef762cc5946fc7a3f89879e76c6ec51e2 ] Before blamed commit, pskb_may_pull() was used instead of skb_header_pointer() in __vlan_get_protocol() and friends. Few callers depended on skb->head being populated with MAC header, syzbot caught one of them (skb_mac_gso_segment()) Add vlan_get_protocol_and_depth() to make the intent clearer and use it where sensible. This is a more generic fix than commit e9d3f80935b6 ("net/af_packet: make sure to pull mac header") which was dealing with a similar issue. kernel BUG at include/linux/skbuff.h:2655 ! invalid opcode: 0000 [#1] SMP KASAN CPU: 0 PID: 1441 Comm: syz-executor199 Not tainted 6.1.24-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:__skb_pull include/linux/skbuff.h:2655 [inline] RIP: 0010:skb_mac_gso_segment+0x68f/0x6a0 net/core/gro.c:136 Code: fd 48 8b 5c 24 10 44 89 6b 70 48 c7 c7 c0 ae 0d 86 44 89 e6 e8 a1 91 d0 00 48 c7 c7 00 af 0d 86 48 89 de 31 d2 e8 d1 4a e9 ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 RSP: 0018:ffffc90001bd7520 EFLAGS: 00010286 RAX: ffffffff8469736a RBX: ffff88810f31dac0 RCX: ffff888115a18b00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001bd75e8 R08: ffffffff84697183 R09: fffff5200037adf9 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000012 R13: 000000000000fee5 R14: 0000000000005865 R15: 000000000000fed7 FS: 000055555633f300(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 0000000116fea000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> [<ffffffff847018dd>] __skb_gso_segment+0x32d/0x4c0 net/core/dev.c:3419 [<ffffffff8470398a>] skb_gso_segment include/linux/netdevice.h:4819 [inline] [<ffffffff8470398a>] validate_xmit_skb+0x3aa/0xee0 net/core/dev.c:3725 [<ffffffff84707042>] __dev_queue_xmit+0x1332/0x3300 net/core/dev.c:4313 [<ffffffff851a9ec7>] dev_queue_xmit+0x17/0x20 include/linux/netdevice.h:3029 [<ffffffff851b4a82>] packet_snd net/packet/af_packet.c:3111 [inline] [<ffffffff851b4a82>] packet_sendmsg+0x49d2/0x6470 net/packet/af_packet.c:3142 [<ffffffff84669a12>] sock_sendmsg_nosec net/socket.c:716 [inline] [<ffffffff84669a12>] sock_sendmsg net/socket.c:736 [inline] [<ffffffff84669a12>] __sys_sendto+0x472/0x5f0 net/socket.c:2139 [<ffffffff84669c75>] __do_sys_sendto net/socket.c:2151 [inline] [<ffffffff84669c75>] __se_sys_sendto net/socket.c:2147 [inline] [<ffffffff84669c75>] __x64_sys_sendto+0xe5/0x100 net/socket.c:2147 [<ffffffff8551d40f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff8551d40f>] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80 [<ffffffff85600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 469aceddfa3e ("vlan: consolidate VLAN parsing code and limit max parsing depth") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Toke Høiland-Jørgensen <toke@redhat.com> Cc: Willem de Bruijn <willemb@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-20net: openvswitch: fix race on port outputFelix Huettner1-0/+1
[ Upstream commit 066b86787fa3d97b7aefb5ac0a99a22dad2d15f8 ] assume the following setup on a single machine: 1. An openvswitch instance with one bridge and default flows 2. two network namespaces "server" and "client" 3. two ovs interfaces "server" and "client" on the bridge 4. for each ovs interface a veth pair with a matching name and 32 rx and tx queues 5. move the ends of the veth pairs to the respective network namespaces 6. assign ip addresses to each of the veth ends in the namespaces (needs to be the same subnet) 7. start some http server on the server network namespace 8. test if a client in the client namespace can reach the http server when following the actions below the host has a chance of getting a cpu stuck in a infinite loop: 1. send a large amount of parallel requests to the http server (around 3000 curls should work) 2. in parallel delete the network namespace (do not delete interfaces or stop the server, just kill the namespace) there is a low chance that this will cause the below kernel cpu stuck message. If this does not happen just retry. Below there is also the output of bpftrace for the functions mentioned in the output. The series of events happening here is: 1. the network namespace is deleted calling `unregister_netdevice_many_notify` somewhere in the process 2. this sets first `NETREG_UNREGISTERING` on both ends of the veth and then runs `synchronize_net` 3. it then calls `call_netdevice_notifiers` with `NETDEV_UNREGISTER` 4. this is then handled by `dp_device_event` which calls `ovs_netdev_detach_dev` (if a vport is found, which is the case for the veth interface attached to ovs) 5. this removes the rx_handlers of the device but does not prevent packages to be sent to the device 6. `dp_device_event` then queues the vport deletion to work in background as a ovs_lock is needed that we do not hold in the unregistration path 7. `unregister_netdevice_many_notify` continues to call `netdev_unregister_kobject` which sets `real_num_tx_queues` to 0 8. port deletion continues (but details are not relevant for this issue) 9. at some future point the background task deletes the vport If after 7. but before 9. a packet is send to the ovs vport (which is not deleted at this point in time) which forwards it to the `dev_queue_xmit` flow even though the device is unregistering. In `skb_tx_hash` (which is called in the `dev_queue_xmit`) path there is a while loop (if the packet has a rx_queue recorded) that is infinite if `dev->real_num_tx_queues` is zero. To prevent this from happening we update `do_output` to handle devices without carrier the same as if the device is not found (which would be the code path after 9. is done). Additionally we now produce a warning in `skb_tx_hash` if we will hit the infinite loop. bpftrace (first word is function name): __dev_queue_xmit server: real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1 netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 2, reg_state: 1 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 6, reg_state: 2 ovs_netdev_detach_dev server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, reg_state: 2 netdev_rx_handler_unregister server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 netdev_rx_handler_unregister ret server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 27, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 22, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 18, reg_state: 2 netdev_unregister_kobject: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 ovs_vport_send server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 __dev_queue_xmit server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 broken device server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024 ovs_dp_detach_port server: real_num_tx_queues: 0 cpu 9, pid: 9124, tid: 9124, reg_state: 2 synchronize_rcu_expedited: cpu 9, pid: 33604, tid: 33604 stuck message: watchdog: BUG: soft lockup - CPU#5 stuck for 26s! [curl:1929279] Modules linked in: veth pktgen bridge stp llc ip_set_hash_net nft_counter xt_set nft_compat nf_tables ip_set_hash_ip ip_set nfnetlink_cttimeout nfnetlink openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 tls binfmt_misc nls_iso8859_1 input_leds joydev serio_raw dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua sch_fq_codel drm efi_pstore virtio_rng ip_tables x_tables autofs4 btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel virtio_net ahci net_failover crypto_simd cryptd psmouse libahci virtio_blk failover CPU: 5 PID: 1929279 Comm: curl Not tainted 5.15.0-67-generic #74-Ubuntu Hardware name: OpenStack Foundation OpenStack Nova, BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:netdev_pick_tx+0xf1/0x320 Code: 00 00 8d 48 ff 0f b7 c1 66 39 ca 0f 86 e9 01 00 00 45 0f b7 ff 41 39 c7 0f 87 5b 01 00 00 44 29 f8 41 39 c7 0f 87 4f 01 00 00 <eb> f2 0f 1f 44 00 00 49 8b 94 24 28 04 00 00 48 85 d2 0f 84 53 01 RSP: 0018:ffffb78b40298820 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff9c8773adc2e0 RCX: 000000000000083f RDX: 0000000000000000 RSI: ffff9c8773adc2e0 RDI: ffff9c870a25e000 RBP: ffffb78b40298858 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff9c870a25e000 R13: ffff9c870a25e000 R14: ffff9c87fe043480 R15: 0000000000000000 FS: 00007f7b80008f00(0000) GS:ffff9c8e5f740000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7b80f6a0b0 CR3: 0000000329d66000 CR4: 0000000000350ee0 Call Trace: <IRQ> netdev_core_pick_tx+0xa4/0xb0 __dev_queue_xmit+0xf8/0x510 ? __bpf_prog_exit+0x1e/0x30 dev_queue_xmit+0x10/0x20 ovs_vport_send+0xad/0x170 [openvswitch] do_output+0x59/0x180 [openvswitch] do_execute_actions+0xa80/0xaa0 [openvswitch] ? kfree+0x1/0x250 ? kfree+0x1/0x250 ? kprobe_perf_func+0x4f/0x2b0 ? flow_lookup.constprop.0+0x5c/0x110 [openvswitch] ovs_execute_actions+0x4c/0x120 [openvswitch] ovs_dp_process_packet+0xa1/0x200 [openvswitch] ? ovs_ct_update_key.isra.0+0xa8/0x120 [openvswitch] ? ovs_ct_fill_key+0x1d/0x30 [openvswitch] ? ovs_flow_key_extract+0x2db/0x350 [openvswitch] ovs_vport_receive+0x77/0xd0 [openvswitch] ? __htab_map_lookup_elem+0x4e/0x60 ? bpf_prog_680e8aff8547aec1_kfree+0x3b/0x714 ? trace_call_bpf+0xc8/0x150 ? kfree+0x1/0x250 ? kfree+0x1/0x250 ? kprobe_perf_func+0x4f/0x2b0 ? kprobe_perf_func+0x4f/0x2b0 ? __mod_memcg_lruvec_state+0x63/0xe0 netdev_port_receive+0xc4/0x180 [openvswitch] ? netdev_port_receive+0x180/0x180 [openvswitch] netdev_frame_hook+0x1f/0x40 [openvswitch] __netif_receive_skb_core.constprop.0+0x23d/0xf00 __netif_receive_skb_one_core+0x3f/0xa0 __netif_receive_skb+0x15/0x60 process_backlog+0x9e/0x170 __napi_poll+0x33/0x180 net_rx_action+0x126/0x280 ? ttwu_do_activate+0x72/0xf0 __do_softirq+0xd9/0x2e7 ? rcu_report_exp_cpu_mult+0x1b0/0x1b0 do_softirq+0x7d/0xb0 </IRQ> <TASK> __local_bh_enable_ip+0x54/0x60 ip_finish_output2+0x191/0x460 __ip_finish_output+0xb7/0x180 ip_finish_output+0x2e/0xc0 ip_output+0x78/0x100 ? __ip_finish_output+0x180/0x180 ip_local_out+0x5e/0x70 __ip_queue_xmit+0x184/0x440 ? tcp_syn_options+0x1f9/0x300 ip_queue_xmit+0x15/0x20 __tcp_transmit_skb+0x910/0x9c0 ? __mod_memcg_state+0x44/0xa0 tcp_connect+0x437/0x4e0 ? ktime_get_with_offset+0x60/0xf0 tcp_v4_connect+0x436/0x530 __inet_stream_connect+0xd4/0x3a0 ? kprobe_perf_func+0x4f/0x2b0 ? aa_sk_perm+0x43/0x1c0 inet_stream_connect+0x3b/0x60 __sys_connect_file+0x63/0x70 __sys_connect+0xa6/0xd0 ? setfl+0x108/0x170 ? do_fcntl+0xe8/0x5a0 __x64_sys_connect+0x18/0x20 do_syscall_64+0x5c/0xc0 ? __x64_sys_fcntl+0xa9/0xd0 ? exit_to_user_mode_prepare+0x37/0xb0 ? syscall_exit_to_user_mode+0x27/0x50 ? do_syscall_64+0x69/0xc0 ? __sys_setsockopt+0xea/0x1e0 ? exit_to_user_mode_prepare+0x37/0xb0 ? syscall_exit_to_user_mode+0x27/0x50 ? __x64_sys_setsockopt+0x1f/0x30 ? do_syscall_64+0x69/0xc0 ? irqentry_exit+0x1d/0x30 ? exc_page_fault+0x89/0x170 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f7b8101c6a7 Code: 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 18 89 54 24 0c 48 89 34 24 89 RSP: 002b:00007ffffd6b2198 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7b8101c6a7 RDX: 0000000000000010 RSI: 00007ffffd6b2360 RDI: 0000000000000005 RBP: 0000561f1370d560 R08: 00002795ad21d1ac R09: 0030312e302e302e R10: 00007ffffd73f080 R11: 0000000000000246 R12: 0000561f1370c410 R13: 0000000000000000 R14: 0000000000000005 R15: 0000000000000000 </TASK> Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action") Co-developed-by: Luca Czesla <luca.czesla@mail.schwarz> Signed-off-by: Luca Czesla <luca.czesla@mail.schwarz> Signed-off-by: Felix Huettner <felix.huettner@mail.schwarz> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Link: https://lore.kernel.org/r/ZC0pBXBAgh7c76CA@kernel-bug-kernel-bug Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11net: fix __dev_kfree_skb_any() vs drop monitorEric Dumazet1-1/+3
[ Upstream commit ac3ad19584b26fae9ac86e4faebe790becc74491 ] dev_kfree_skb() is aliased to consume_skb(). When a driver is dropping a packet by calling dev_kfree_skb_any() we should propagate the drop reason instead of pretending the packet was consumed. Note: Now we have enum skb_drop_reason we could remove enum skb_free_reason (for linux-6.4) v2: added an unlikely(), suggested by Yunsheng Lin. Fixes: e6247027e517 ("net: introduce dev_consume_skb_any()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yunsheng Lin <linyunsheng@huawei.com> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-22net: Fix unwanted sign extension in netdev_stats_to_stats64()Felix Riemann1-1/+1
commit 9b55d3f0a69af649c62cbc2633e6d695bb3cc583 upstream. When converting net_device_stats to rtnl_link_stats64 sign extension is triggered on ILP32 machines as 6c1c509778 changed the previous "ulong -> u64" conversion to "long -> u64" by accessing the net_device_stats fields through a (signed) atomic_long_t. This causes for example the received bytes counter to jump to 16EiB after having received 2^31 bytes. Casting the atomic value to "unsigned long" beforehand converting it into u64 avoids this. Fixes: 6c1c5097781f ("net: add atomic_long_t to net_device_stats fields") Signed-off-by: Felix Riemann <felix.riemann@sma.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-31net: add atomic_long_t to net_device_stats fieldsEric Dumazet1-11/+3
[ Upstream commit 6c1c5097781f563b70a81683ea6fdac21637573b ] Long standing KCSAN issues are caused by data-race around some dev->stats changes. Most performance critical paths already use per-cpu variables, or per-queue ones. It is reasonable (and more correct) to use atomic operations for the slow paths. This patch adds an union for each field of net_device_stats, so that we can convert paths that are not yet protected by a spinlock or a mutex. netdev_stats_to_stats64() no longer has an #if BITS_PER_LONG==64 Note that the memcpy() we were using on 64bit arches had no provision to avoid load-tearing, while atomic_long_read() is providing the needed protection at no cost. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-19net: Fix return value of qdisc ingress handling on successPaul Blakey1-0/+4
Currently qdisc ingress handling (sch_handle_ingress()) doesn't set a return value and it is left to the old return value of the caller (__netif_receive_skb_core()) which is RX drop, so if the packet is consumed, caller will stop and return this value as if the packet was dropped. This causes a problem in the kernel tcp stack when having a egress tc rule forwarding to a ingress tc rule. The tcp stack sending packets on the device having the egress rule will see the packets as not successfully transmitted (although they actually were), will not advance it's internal state of sent data, and packets returning on such tcp stream will be dropped by the tcp stack with reason ack-of-unsent-data. See reproduction in [0] below. Fix that by setting the return value to RX success if the packet was handled successfully. [0] Reproduction steps: $ ip link add veth1 type veth peer name peer1 $ ip link add veth2 type veth peer name peer2 $ ifconfig peer1 5.5.5.6/24 up $ ip netns add ns0 $ ip link set dev peer2 netns ns0 $ ip netns exec ns0 ifconfig peer2 5.5.5.5/24 up $ ifconfig veth2 0 up $ ifconfig veth1 0 up #ingress forwarding veth1 <-> veth2 $ tc qdisc add dev veth2 ingress $ tc qdisc add dev veth1 ingress $ tc filter add dev veth2 ingress prio 1 proto all flower \ action mirred egress redirect dev veth1 $ tc filter add dev veth1 ingress prio 1 proto all flower \ action mirred egress redirect dev veth2 #steal packet from peer1 egress to veth2 ingress, bypassing the veth pipe $ tc qdisc add dev peer1 clsact $ tc filter add dev peer1 egress prio 20 proto ip flower \ action mirred ingress redirect dev veth1 #run iperf and see connection not running $ iperf3 -s& $ ip netns exec ns0 iperf3 -c 5.5.5.6 -i 1 #delete egress rule, and run again, now should work $ tc filter del dev peer1 egress $ ip netns exec ns0 iperf3 -c 5.5.5.6 -i 1 Fixes: f697c3e8b35c ("[NET]: Avoid unnecessary cloning for ingress filtering") Signed-off-by: Paul Blakey <paulb@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-30net: skb: introduce and use a single page frag cachePaolo Abeni1-17/+0
After commit 3226b158e67c ("net: avoid 32 x truesize under-estimation for tiny skbs") we are observing 10-20% regressions in performance tests with small packets. The perf trace points to high pressure on the slab allocator. This change tries to improve the allocation schema for small packets using an idea originally suggested by Eric: a new per CPU page frag is introduced and used in __napi_alloc_skb to cope with small allocation requests. To ensure that the above does not lead to excessive truesize underestimation, the frag size for small allocation is inflated to 1K and all the above is restricted to build with 4K page size. Note that we need to update accordingly the run-time check introduced with commit fd9ea57f4e95 ("net: add napi_get_frags_check() helper"). Alex suggested a smart page refcount schema to reduce the number of atomic operations and deal properly with pfmemalloc pages. Under small packet UDP flood, I measure a 15% peak tput increases. Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Suggested-by: Alexander H Duyck <alexanderduyck@fb.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Link: https://lore.kernel.org/r/6b6f65957c59f86a353fc09a5127e83a32ab5999.1664350652.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-10/+10
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: Fix a data-race around netdev_unregister_timeout_secs.Kuniyuki Iwashima1-1/+1
While reading netdev_unregister_timeout_secs, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 5aa3afe107d9 ("net: make unregister netdev warning timeout configurable") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24net: Fix a data-race around netdev_budget_usecs.Kuniyuki Iwashima1-1/+1
While reading netdev_budget_usecs, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 7acf8a1e8a28 ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24net: Fix a data-race around netdev_budget.Kuniyuki Iwashima1-1/+1
While reading netdev_budget, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 51b0bdedb8e7 ("[NET]: Separate two usages of netdev_max_backlog.") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24net: Fix data-races around netdev_tstamp_prequeue.Kuniyuki Iwashima1-4/+4
While reading netdev_tstamp_prequeue, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 3b098e2d7c69 ("net: Consistent skb timestamping") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24net: Fix data-races around netdev_max_backlog.Kuniyuki Iwashima1-2/+2
While reading netdev_max_backlog, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. While at it, we remove the unnecessary spaces in the doc. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24net: Fix data-races around weight_p and dev_weight_[rt]x_bias.Kuniyuki Iwashima1-1/+1
While reading weight_p, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Also, dev_[rt]x_weight can be read/written at the same time. So, we need to use READ_ONCE() and WRITE_ONCE() for its access. Moreover, to use the same weight_p while changing dev_[rt]x_weight, we add a mutex in proc_do_dev_weight(). Fixes: 3d48b53fb2ae ("net: dev_weight: TX/RX orthogonality") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-23net: move from strlcpy with unused retval to strscpyWolfram Sang1-2/+2
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20220818210215.8395-1-wsa+renesas@sang-engineering.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-22Remove DECnet support from kernelStephen Hemminger1-3/+1
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>
2022-07-23Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski1-0/+1
Daniel Borkmann says: ==================== bpf-next 2022-07-22 We've added 73 non-merge commits during the last 12 day(s) which contain a total of 88 files changed, 3458 insertions(+), 860 deletions(-). The main changes are: 1) Implement BPF trampoline for arm64 JIT, from Xu Kuohai. 2) Add ksyscall/kretsyscall section support to libbpf to simplify tracing kernel syscalls through kprobe mechanism, from Andrii Nakryiko. 3) Allow for livepatch (KLP) and BPF trampolines to attach to the same kernel function, from Song Liu & Jiri Olsa. 4) Add new kfunc infrastructure for netfilter's CT e.g. to insert and change entries, from Kumar Kartikeya Dwivedi & Lorenzo Bianconi. 5) Add a ksym BPF iterator to allow for more flexible and efficient interactions with kernel symbols, from Alan Maguire. 6) Bug fixes in libbpf e.g. for uprobe binary path resolution, from Dan Carpenter. 7) Fix BPF subprog function names in stack traces, from Alexei Starovoitov. 8) libbpf support for writing custom perf event readers, from Jon Doron. 9) Switch to use SPDX tag for BPF helper man page, from Alejandro Colomar. 10) Fix xsk send-only sockets when in busy poll mode, from Maciej Fijalkowski. 11) Reparent BPF maps and their charging on memcg offlining, from Roman Gushchin. 12) Multiple follow-up fixes around BPF lsm cgroup infra, from Stanislav Fomichev. 13) Use bootstrap version of bpftool where possible to speed up builds, from Pu Lehui. 14) Cleanup BPF verifier's check_func_arg() handling, from Joanne Koong. 15) Make non-prealloced BPF map allocations low priority to play better with memcg limits, from Yafang Shao. 16) Fix BPF test runner to reject zero-length data for skbs, from Zhengchao Shao. 17) Various smaller cleanups and improvements all over the place. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (73 commits) bpf: Simplify bpf_prog_pack_[size|mask] bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch) bpf, x64: Allow to use caller address from stack ftrace: Allow IPMODIFY and DIRECT ops on the same function ftrace: Add modify_ftrace_direct_multi_nolock bpf/selftests: Fix couldn't retrieve pinned program in xdp veth test bpf: Fix build error in case of !CONFIG_DEBUG_INFO_BTF selftests/bpf: Fix test_verifier failed test in unprivileged mode selftests/bpf: Add negative tests for new nf_conntrack kfuncs selftests/bpf: Add tests for new nf_conntrack kfuncs selftests/bpf: Add verifier tests for trusted kfunc args net: netfilter: Add kfuncs to set and change CT status net: netfilter: Add kfuncs to set and change CT timeout net: netfilter: Add kfuncs to allocate and insert CT net: netfilter: Deduplicate code in bpf_{xdp,skb}_ct_lookup bpf: Add documentation for kfuncs bpf: Add support for forcing kfunc args to be trusted bpf: Switch to new kfunc flags infrastructure tools/resolve_btfids: Add support for 8-byte BTF sets bpf: Introduce 8-byte BTF set ... ==================== Link: https://lore.kernel.org/r/20220722221218.29943-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-19bpf: Don't redirect packets with invalid pkt_lenZhengchao Shao1-0/+1
Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any skbs, that is, the flow->head is null. The root cause, as the [2] says, is because that bpf_prog_test_run_skb() run a bpf prog which redirects empty skbs. So we should determine whether the length of the packet modified by bpf prog or others like bpf_prog_test is valid before forwarding it directly. LINK: [1] https://syzkaller.appspot.com/bug?id=0b84da80c2917757915afa89f7738a9d16ec96c5 LINK: [2] https://www.spinics.net/lists/netdev/msg777503.html Reported-by: syzbot+7a12909485b94426aceb@syzkaller.appspotmail.com Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20220715115559.139691-1-shaozhengchao@huawei.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-2/+6
include/net/sock.h 310731e2f161 ("net: Fix data-races around sysctl_mem.") e70f3c701276 ("Revert "net: set SK_MEM_QUANTUM to 4096"") https://lore.kernel.org/all/20220711120211.7c8b7cba@canb.auug.org.au/ net/ipv4/fib_semantics.c 747c14307214 ("ip: fix dflt addr selection for connected nexthop") d62607c3fe45 ("net: rename reference+tracking helpers") net/tls/tls.h include/net/tls.h 3d8c51b25a23 ("net/tls: Check for errors in tls_device_init") 587903142308 ("tls: create an internal header") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-06xdp: Fix spurious packet loss in generic XDP TX pathJohan Almbladh1-2/+6
The byte queue limits (BQL) mechanism is intended to move queuing from the driver to the network stack in order to reduce latency caused by excessive queuing in hardware. However, when transmitting or redirecting a packet using generic XDP, the qdisc layer is bypassed and there are no additional queues. Since netif_xmit_stopped() also takes BQL limits into account, but without having any alternative queuing, packets are silently dropped. This patch modifies the drop condition to only consider cases when the driver itself cannot accept any more packets. This is analogous to the condition in __dev_direct_xmit(). Dropped packets are also counted on the device. Bypassing the qdisc layer in the generic XDP TX path means that XDP packets are able to starve other packets going through a qdisc, and DDOS attacks will be more effective. In-driver-XDP use dedicated TX queues, so they do not have this starvation issue. Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220705082345.2494312-1-johan.almbladh@anyfinetworks.com
2022-06-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-10/+15
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-17net: fix data-race in dev_isalive()Eric Dumazet1-10/+15
dev_isalive() is called under RTNL or dev_base_lock protection. This means that changes to dev->reg_state should be done with both locks held. syzbot reported: BUG: KCSAN: data-race in register_netdevice / type_show write to 0xffff888144ecf518 of 1 bytes by task 20886 on cpu 0: register_netdevice+0xb9f/0xdf0 net/core/dev.c:10050 lapbeth_new_device drivers/net/wan/lapbether.c:414 [inline] lapbeth_device_event+0x4a0/0x6c0 drivers/net/wan/lapbether.c:456 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0x53/0xb0 kernel/notifier.c:455 __dev_notify_flags+0x1d6/0x3a0 dev_change_flags+0xa2/0xc0 net/core/dev.c:8607 do_setlink+0x778/0x2230 net/core/rtnetlink.c:2780 __rtnl_newlink net/core/rtnetlink.c:3546 [inline] rtnl_newlink+0x114c/0x16a0 net/core/rtnetlink.c:3593 rtnetlink_rcv_msg+0x811/0x8c0 net/core/rtnetlink.c:6089 netlink_rcv_skb+0x13e/0x240 net/netlink/af_netlink.c:2501 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:6107 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x58a/0x660 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x661/0x750 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] __sys_sendto+0x21e/0x2c0 net/socket.c:2119 __do_sys_sendto net/socket.c:2131 [inline] __se_sys_sendto net/socket.c:2127 [inline] __x64_sys_sendto+0x74/0x90 net/socket.c:2127 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 read to 0xffff888144ecf518 of 1 bytes by task 20423 on cpu 1: dev_isalive net/core/net-sysfs.c:38 [inline] netdev_show net/core/net-sysfs.c:50 [inline] type_show+0x24/0x90 net/core/net-sysfs.c:112 dev_attr_show+0x35/0x90 drivers/base/core.c:2095 sysfs_kf_seq_show+0x175/0x240 fs/sysfs/file.c:59 kernfs_seq_show+0x75/0x80 fs/kernfs/file.c:162 seq_read_iter+0x2c3/0x8e0 fs/seq_file.c:230 kernfs_fop_read_iter+0xd1/0x2f0 fs/kernfs/file.c:235 call_read_iter include/linux/fs.h:2052 [inline] new_sync_read fs/read_write.c:401 [inline] vfs_read+0x5a5/0x6a0 fs/read_write.c:482 ksys_read+0xe8/0x1a0 fs/read_write.c:620 __do_sys_read fs/read_write.c:630 [inline] __se_sys_read fs/read_write.c:628 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:628 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 value changed: 0x00 -> 0x01 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 20423 Comm: udevd Tainted: G W 5.19.0-rc2-syzkaller-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-10net: add napi_get_frags_check() helperEric Dumazet1-0/+18
This is a follow up of commit 3226b158e67c ("net: avoid 32 x truesize under-estimation for tiny skbs") When/if we increase MAX_SKB_FRAGS, we better make sure the old bug will not come back. Adding a check in napi_get_frags() would be costly, even if using DEBUG_NET_WARN_ON_ONCE(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-10net: use DEBUG_NET_WARN_ON_ONCE() in dev_loopback_xmit()Eric Dumazet1-1/+1
One check in dev_loopback_xmit() has not caught issues in the past. Keep it for CONFIG_DEBUG_NET=y builds only. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-10net: adopt u64_stats_t in struct pcpu_sw_netstatsEric Dumazet1-9/+9
As explained in commit 316580b69d0a ("u64_stats: provide u64_stats_t type") we should use u64_stats_t and related accessors to avoid load/store tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-10net: rename reference+tracking helpersJakub Kicinski1-5/+5
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>
2022-05-25Merge tag 'net-next-5.19' of ↵Linus Torvalds1-70/+162
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core ---- - Support TCPv6 segmentation offload with super-segments larger than 64k bytes using the IPv6 Jumbogram extension header (AKA BIG TCP). - Generalize skb freeing deferral to per-cpu lists, instead of per-socket lists. - Add a netdev statistic for packets dropped due to L2 address mismatch (rx_otherhost_dropped). - Continue work annotating skb drop reasons. - Accept alternative netdev names (ALT_IFNAME) in more netlink requests. - Add VLAN support for AF_PACKET SOCK_RAW GSO. - Allow receiving skb mark from the socket as a cmsg. - Enable memcg accounting for veth queues, sysctl tables and IPv6. BPF --- - Add libbpf support for User Statically-Defined Tracing (USDTs). - Speed up symbol resolution for kprobes multi-link attachments. - Support storing typed pointers to referenced and unreferenced objects in BPF maps. - Add support for BPF link iterator. - Introduce access to remote CPU map elements in BPF per-cpu map. - Allow middle-of-the-road settings for the kernel.unprivileged_bpf_disabled sysctl. - Implement basic types of dynamic pointers e.g. to allow for dynamically sized ringbuf reservations without extra memory copies. Protocols --------- - Retire port only listening_hash table, add a second bind table hashed by port and address. Avoid linear list walk when binding to very popular ports (e.g. 443). - Add bridge FDB bulk flush filtering support allowing user space to remove all FDB entries matching a condition. - Introduce accept_unsolicited_na sysctl for IPv6 to implement router-side changes for RFC9131. - Support for MPTCP path manager in user space. - Add MPTCP support for fallback to regular TCP for connections that have never connected additional subflows or transmitted out-of-sequence data (partial support for RFC8684 fallback). - Avoid races in MPTCP-level window tracking, stabilize and improve throughput. - Support lockless operation of GRE tunnels with seq numbers enabled. - WiFi support for host based BSS color collision detection. - Add support for SO_TXTIME/SCM_TXTIME on CAN sockets. - Support transmission w/o flow control in CAN ISOTP (ISO 15765-2). - Support zero-copy Tx with TLS 1.2 crypto offload (sendfile). - Allow matching on the number of VLAN tags via tc-flower. - Add tracepoint for tcp_set_ca_state(). Driver API ---------- - Improve error reporting from classifier and action offload. - Add support for listing line cards in switches (devlink). - Add helpers for reporting page pool statistics with ethtool -S. - Add support for reading clock cycles when using PTP virtual clocks, instead of having the driver convert to time before reporting. This makes it possible to report time from different vclocks. - Support configuring low-latency Tx descriptor push via ethtool. - Separate Clause 22 and Clause 45 MDIO accesses more explicitly. New hardware / drivers ---------------------- - Ethernet: - Marvell's Octeon NIC PCI Endpoint support (octeon_ep) - Sunplus SP7021 SoC (sp7021_emac) - Add support for Renesas RZ/V2M (in ravb) - Add support for MediaTek mt7986 switches (in mtk_eth_soc) - Ethernet PHYs: - ADIN1100 industrial PHYs (w/ 10BASE-T1L and SQI reporting) - TI DP83TD510 PHY - Microchip LAN8742/LAN88xx PHYs - WiFi: - Driver for pureLiFi X, XL, XC devices (plfxlc) - Driver for Silicon Labs devices (wfx) - Support for WCN6750 (in ath11k) - Support Realtek 8852ce devices (in rtw89) - Mobile: - MediaTek T700 modems (Intel 5G 5000 M.2 cards) - CAN: - ctucanfd: add support for CTU CAN FD open-source IP core from Czech Technical University in Prague Drivers ------- - Delete a number of old drivers still using virt_to_bus(). - Ethernet NICs: - intel: support TSO on tunnels MPLS - broadcom: support multi-buffer XDP - nfp: support VF rate limiting - sfc: use hardware tx timestamps for more than PTP - mlx5: multi-port eswitch support - hyper-v: add support for XDP_REDIRECT - atlantic: XDP support (including multi-buffer) - macb: improve real-time perf by deferring Tx processing to NAPI - High-speed Ethernet switches: - mlxsw: implement basic line card information querying - prestera: add support for traffic policing on ingress and egress - Embedded Ethernet switches: - lan966x: add support for packet DMA (FDMA) - lan966x: add support for PTP programmable pins - ti: cpsw_new: enable bc/mc storm prevention - Qualcomm 802.11ax WiFi (ath11k): - Wake-on-WLAN support for QCA6390 and WCN6855 - device recovery (firmware restart) support - support setting Specific Absorption Rate (SAR) for WCN6855 - read country code from SMBIOS for WCN6855/QCA6390 - enable keep-alive during WoWLAN suspend - implement remain-on-channel support - MediaTek WiFi (mt76): - support Wireless Ethernet Dispatch offloading packet movement between the Ethernet switch and WiFi interfaces - non-standard VHT MCS10-11 support - mt7921 AP mode support - mt7921 IPv6 NS offload support - Ethernet PHYs: - micrel: ksz9031/ksz9131: cabletest support - lan87xx: SQI support for T1 PHYs - lan937x: add interrupt support for link detection" * tag 'net-next-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1809 commits) ptp: ocp: Add firmware header checks ptp: ocp: fix PPS source selector debugfs reporting ptp: ocp: add .init function for sma_op vector ptp: ocp: vectorize the sma accessor functions ptp: ocp: constify selectors ptp: ocp: parameterize input/output sma selectors ptp: ocp: revise firmware display ptp: ocp: add Celestica timecard PCI ids ptp: ocp: Remove #ifdefs around PCI IDs ptp: ocp: 32-bit fixups for pci start address Revert "net/smc: fix listen processing for SMC-Rv2" ath6kl: Use cc-disable-warning to disable -Wdangling-pointer selftests/bpf: Dynptr tests bpf: Add dynptr data slices bpf: Add bpf_dynptr_read and bpf_dynptr_write bpf: Dynptr support for ring buffers bpf: Add bpf_dynptr_from_mem for local dynptrs bpf: Add verifier support for dynptrs bpf: Suppress 'passing zero to PTR_ERR' warning bpf: Introduce bpf_arch_text_invalidate for bpf_prog_pack ...
2022-05-24Merge tag 'random-5.19-rc1-for-linus' of ↵Linus Torvalds1-3/+0
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull random number generator updates from Jason Donenfeld: "These updates continue to refine the work began in 5.17 and 5.18 of modernizing the RNG's crypto and streamlining and documenting its code. New for 5.19, the updates aim to improve entropy collection methods and make some initial decisions regarding the "premature next" problem and our threat model. The cloc utility now reports that random.c is 931 lines of code and 466 lines of comments, not that basic metrics like that mean all that much, but at the very least it tells you that this is very much a manageable driver now. Here's a summary of the various updates: - The random_get_entropy() function now always returns something at least minimally useful. This is the primary entropy source in most collectors, which in the best case expands to something like RDTSC, but prior to this change, in the worst case it would just return 0, contributing nothing. For 5.19, additional architectures are wired up, and architectures that are entirely missing a cycle counter now have a generic fallback path, which uses the highest resolution clock available from the timekeeping subsystem. Some of those clocks can actually be quite good, despite the CPU not having a cycle counter of its own, and going off-core for a stamp is generally thought to increase jitter, something positive from the perspective of entropy gathering. Done very early on in the development cycle, this has been sitting in next getting some testing for a while now and has relevant acks from the archs, so it should be pretty well tested and fine, but is nonetheless the thing I'll be keeping my eye on most closely. - Of particular note with the random_get_entropy() improvements is MIPS, which, on CPUs that lack the c0 count register, will now combine the high-speed but short-cycle c0 random register with the lower-speed but long-cycle generic fallback path. - With random_get_entropy() now always returning something useful, the interrupt handler now collects entropy in a consistent construction. - Rather than comparing two samples of random_get_entropy() for the jitter dance, the algorithm now tests many samples, and uses the amount of differing ones to determine whether or not jitter entropy is usable and how laborious it must be. The problem with comparing only two samples was that if the cycle counter was extremely slow, but just so happened to be on the cusp of a change, the slowness wouldn't be detected. Taking many samples fixes that to some degree. This, combined with the other improvements to random_get_entropy(), should make future unification of /dev/random and /dev/urandom maybe more possible. At the very least, were we to attempt it again today (we're not), it wouldn't break any of Guenter's test rigs that broke when we tried it with 5.18. So, not today, but perhaps down the road, that's something we can revisit. - We attempt to reseed the RNG immediately upon waking up from system suspend or hibernation, making use of the various timestamps about suspend time and such available, as well as the usual inputs such as RDRAND when available. - Batched randomness now falls back to ordinary randomness before the RNG is initialized. This provides more consistent guarantees to the types of random numbers being returned by the various accessors. - The "pre-init injection" code is now gone for good. I suspect you in particular will be happy to read that, as I recall you expressing your distaste for it a few months ago. Instead, to avoid a "premature first" issue, while still allowing for maximal amount of entropy availability during system boot, the first 128 bits of estimated entropy are used immediately as it arrives, with the next 128 bits being buffered. And, as before, after the RNG has been fully initialized, it winds up reseeding anyway a few seconds later in most cases. This resulted in a pretty big simplification of the initialization code and let us remove various ad-hoc mechanisms like the ugly crng_pre_init_inject(). - The RNG no longer pretends to handle the "premature next" security model, something that various academics and other RNG designs have tried to care about in the past. After an interesting mailing list thread, these issues are thought to be a) mainly academic and not practical at all, and b) actively harming the real security of the RNG by delaying new entropy additions after a potential compromise, making a potentially bad situation even worse. As well, in the first place, our RNG never even properly handled the premature next issue, so removing an incomplete solution to a fake problem was particularly nice. This allowed for numerous other simplifications in the code, which is a lot cleaner as a consequence. If you didn't see it before, https://lore.kernel.org/lkml/YmlMGx6+uigkGiZ0@zx2c4.com/ may be a thread worth skimming through. - While the interrupt handler received a separate code path years ago that avoids locks by using per-cpu data structures and a faster mixing algorithm, in order to reduce interrupt latency, input and disk events that are triggered in hardirq handlers were still hitting locks and more expensive algorithms. Those are now redirected to use the faster per-cpu data structures. - Rather than having the fake-crypto almost-siphash-based random32 implementation be used right and left, and in many places where cryptographically secure randomness is desirable, the batched entropy code is now fast enough to replace that. - As usual, numerous code quality and documentation cleanups. For example, the initialization state machine now uses enum symbolic constants instead of just hard coding numbers everywhere. - Since the RNG initializes once, and then is always initialized thereafter, a pretty heavy amount of code used during that initialization is never used again. It is now completely cordoned off using static branches and it winds up in the .text.unlikely section so that it doesn't reduce cache compactness after the RNG is ready. - A variety of functions meant for waiting on the RNG to be initialized were only used by vsprintf, and in not a particularly optimal way. Replacing that usage with a more ordinary setup made it possible to remove those functions. - A cleanup of how we warn userspace about the use of uninitialized /dev/urandom and uninitialized get_random_bytes() usage. Interestingly, with the change you merged for 5.18 that attempts to use jitter (but does not block if it can't), the majority of users should never see those warnings for /dev/urandom at all now, and the one for in-kernel usage is mainly a debug thing. - The file_operations struct for /dev/[u]random now implements .read_iter and .write_iter instead of .read and .write, allowing it to also implement .splice_read and .splice_write, which makes splice(2) work again after it was broken here (and in many other places in the tree) during the set_fs() removal. This was a bit of a last minute arrival from Jens that hasn't had as much time to bake, so I'll be keeping my eye on this as well, but it seems fairly ordinary. Unfortunately, read_iter() is around 3% slower than read() in my tests, which I'm not thrilled about. But Jens and Al, spurred by this observation, seem to be making progress in removing the bottlenecks on the iter paths in the VFS layer in general, which should remove the performance gap for all drivers. - Assorted other bug fixes, cleanups, and optimizations. - A small SipHash cleanup" * tag 'random-5.19-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (49 commits) random: check for signals after page of pool writes random: wire up fops->splice_{read,write}_iter() random: convert to using fops->write_iter() random: convert to using fops->read_iter() random: unify batched entropy implementations random: move randomize_page() into mm where it belongs random: remove mostly unused async readiness notifier random: remove get_random_bytes_arch() and add rng_has_arch_random() random: move initialization functions out of hot pages random: make consistent use of buf and len random: use proper return types on get_random_{int,long}_wait() random: remove extern from functions in header random: use static branch for crng_ready() random: credit architectural init the exact amount random: handle latent entropy and command line from random_init() random: use proper jiffies comparison macro random: remove ratelimiting for in-kernel unseeded randomness random: move initialization out of reseeding hot path random: avoid initializing twice in credit race random: use symbolic constants for crng_init states ...
2022-05-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+1
drivers/net/ethernet/mellanox/mlx5/core/main.c b33886971dbc ("net/mlx5: Initialize flow steering during driver probe") 40379a0084c2 ("net/mlx5_fpga: Drop INNOVA TLS support") f2b41b32cde8 ("net/mlx5: Remove ipsec_ops function table") https://lore.kernel.org/all/20220519040345.6yrjromcdistu7vh@sx1/ 16d42d313350 ("net/mlx5: Drain fw_reset when removing device") 8324a02c342a ("net/mlx5: Add exit route when waiting for FW") https://lore.kernel.org/all/20220519114119.060ce014@canb.auug.org.au/ tools/testing/selftests/net/mptcp/mptcp_join.sh e274f7154008 ("selftests: mptcp: add subflow limits test-cases") b6e074e171bc ("selftests: mptcp: add infinite map testcase") 5ac1d2d63451 ("selftests: mptcp: Add tests for userspace PM type") https://lore.kernel.org/all/20220516111918.366d747f@canb.auug.org.au/ net/mptcp/options.c ba2c89e0ea74 ("mptcp: fix checksum byte order") 1e39e5a32ad7 ("mptcp: infinite mapping sending") ea66758c1795 ("tcp: allow MPTCP to update the announced window") https://lore.kernel.org/all/20220519115146.751c3a37@canb.auug.org.au/ net/mptcp/pm.c 95d686517884 ("mptcp: fix subflow accounting on close") 4d25247d3ae4 ("mptcp: bypass in-kernel PM restrictions for non-kernel PMs") https://lore.kernel.org/all/20220516111435.72f35dca@canb.auug.org.au/ net/mptcp/subflow.c ae66fb2ba6c3 ("mptcp: Do TCP fallback on early DSS checksum failure") 0348c690ed37 ("mptcp: add the fallback check") f8d4bcacff3b ("mptcp: infinite mapping receiving") https://lore.kernel.org/all/20220519115837.380bb8d4@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-18random32: use real rng for non-deterministic randomnessJason A. Donenfeld1-3/+0
random32.c has two random number generators in it: one that is meant to be used deterministically, with some predefined seed, and one that does the same exact thing as random.c, except does it poorly. The first one has some use cases. The second one no longer does and can be replaced with calls to random.c's proper random number generator. The relatively recent siphash-based bad random32.c code was added in response to concerns that the prior random32.c was too deterministic. Out of fears that random.c was (at the time) too slow, this code was anonymously contributed. Then out of that emerged a kind of shadow entropy gathering system, with its own tentacles throughout various net code, added willy nilly. Stop👏making👏bespoke👏random👏number👏generators👏. Fortunately, recent advances in random.c mean that we can stop playing with this sketchiness, and just use get_random_u32(), which is now fast enough. In micro benchmarks using RDPMC, I'm seeing the same median cycle count between the two functions, with the mean being _slightly_ higher due to batches refilling (which we can optimize further need be). However, when doing *real* benchmarks of the net functions that actually use these random numbers, the mean cycles actually *decreased* slightly (with the median still staying the same), likely because the additional prandom code means icache misses and complexity, whereas random.c is generally already being used by something else nearby. The biggest benefit of this is that there are many users of prandom who probably should be using cryptographically secure random numbers. This makes all of those accidental cases become secure by just flipping a switch. Later on, we can do a tree-wide cleanup to remove the static inline wrapper functions that this commit adds. There are also some low-ish hanging fruits for making this even faster in the future: a get_random_u16() function for use in the networking stack will give a 2x performance boost there, using SIMD for ChaCha20 will let us compute 4 or 8 or 16 blocks of output in parallel, instead of just one, giving us large buffers for cheap, and introducing a get_random_*_bh() function that assumes irqs are already disabled will shave off a few cycles for ordinary calls. These are things we can chip away at down the road. Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-05-16net: fix dev_fill_forward_path with pppoe + bridgeFelix Fietkau1-1/+1
When calling dev_fill_forward_path on a pppoe device, the provided destination address is invalid. In order for the bridge fdb lookup to succeed, the pppoe code needs to update ctx->daddr to the correct value. Fix this by storing the address inside struct net_device_path_ctx Fixes: f6efc675c9dd ("net: ppp: resolve forwarding path for bridge pppoe devices") Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-16net: call skb_defer_free_flush() before each napi_poll()Eric Dumazet1-2/+3
skb_defer_free_flush() can consume cpu cycles, it seems better to call it in the inner loop: - Potentially frees page/skb that will be reallocated while hot. - Account for the cpu cycles in the @time_limit determination. - Keep softnet_data.defer_count small to reduce chances for skb_attempt_defer_free() to send an IPI. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-16net: add skb_defer_max sysctlEric Dumazet1-0/+1
commit 68822bdf76f1 ("net: generalize skb freeing deferral to per-cpu lists") added another per-cpu cache of skbs. It was expected to be small, and an IPI was forced whenever the list reached 128 skbs. We might need to be able to control more precisely queue capacity and added latency. An IPI is generated whenever queue reaches half capacity. Default value of the new limit is 64. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-16net: use napi_consume_skb() in skb_defer_free_flush()Eric Dumazet1-1/+1
skb_defer_free_flush() runs from softirq context, we have the opportunity to refill the napi_alloc_cache, and/or use kmem_cache_free_bulk() when this cache is full. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-16net: fix possible race in skb_attempt_defer_free()Eric Dumazet1-2/+5
A cpu can observe sd->defer_count reaching 128, and call smp_call_function_single_async() Problem is that the remote CPU can clear sd->defer_count before the IPI is run/acknowledged. Other cpus can queue more packets and also decide to call smp_call_function_single_async() while the pending IPI was not yet delivered. This is a common issue with smp_call_function_single_async(). Callers must ensure correct synchronization and serialization. I triggered this issue while experimenting smaller threshold. Performing the call to smp_call_function_single_async() under sd->defer_lock protection did not solve the problem. Commit 5a18ceca6350 ("smp: Allow smp_call_function_single_async() to insert locked csd") replaced an informative WARN_ON_ONCE() with a return of -EBUSY, which is often ignored. Test of CSD_FLAG_LOCK presence is racy anyway. Fixes: 68822bdf76f1 ("net: generalize skb freeing deferral to per-cpu lists") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-16net: allow gro_max_size to exceed 65536Alexander Duyck1-1/+1
Allow the gro_max_size to exceed a value larger than 65536. There weren't really any external limitations that prevented this other than the fact that IPv4 only supports a 16 bit length field. Since we have the option of adding a hop-by-hop header for IPv6 we can allow IPv6 to exceed this value and for IPv4 and non-TCP flows we can cap things at 65536 via a constant rather than relying on gro_max_size. [edumazet] limit GRO_MAX_SIZE to (8 * 65535) to avoid overflows. Signed-off-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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