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2021-12-03tcp: fix another uninit-value (sk_rx_queue_mapping)Eric Dumazet1-0/+13
KMSAN is still not happy [1]. I missed that passive connections do not inherit their sk_rx_queue_mapping values from the request socket, but instead tcp_child_process() is calling sk_mark_napi_id(child, skb) We have many sk_mark_napi_id() callers, so I am providing a new helper, forcing the setting sk_rx_queue_mapping and sk_napi_id. Note that we had no KMSAN report for sk_napi_id because passive connections got a copy of this field from the listener. sk_rx_queue_mapping in the other hand is inside the sk_dontcopy_begin/sk_dontcopy_end so sk_clone_lock() leaves this field uninitialized. We might remove dead code populating req->sk_rx_queue_mapping in the future. [1] BUG: KMSAN: uninit-value in __sk_rx_queue_set include/net/sock.h:1924 [inline] BUG: KMSAN: uninit-value in sk_rx_queue_update include/net/sock.h:1938 [inline] BUG: KMSAN: uninit-value in sk_mark_napi_id include/net/busy_poll.h:136 [inline] BUG: KMSAN: uninit-value in tcp_child_process+0xb42/0x1050 net/ipv4/tcp_minisocks.c:833 __sk_rx_queue_set include/net/sock.h:1924 [inline] sk_rx_queue_update include/net/sock.h:1938 [inline] sk_mark_napi_id include/net/busy_poll.h:136 [inline] tcp_child_process+0xb42/0x1050 net/ipv4/tcp_minisocks.c:833 tcp_v4_rcv+0x3d83/0x4ed0 net/ipv4/tcp_ipv4.c:2066 ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline] ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609 ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5505 [inline] __netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553 __netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605 netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696 gro_normal_list net/core/dev.c:5850 [inline] napi_complete_done+0x579/0xdd0 net/core/dev.c:6587 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x824/0x1880 net/core/dev.c:7174 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558 run_ksoftirqd+0x33/0x50 kernel/softirq.c:920 smpboot_thread_fn+0x616/0xbf0 kernel/smpboot.c:164 kthread+0x721/0x850 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 Uninit was created at: __alloc_pages+0xbc7/0x10a0 mm/page_alloc.c:5409 alloc_pages+0x8a5/0xb80 alloc_slab_page mm/slub.c:1810 [inline] allocate_slab+0x287/0x1c20 mm/slub.c:1947 new_slab mm/slub.c:2010 [inline] ___slab_alloc+0xbdf/0x1e90 mm/slub.c:3039 __slab_alloc mm/slub.c:3126 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3259 [inline] kmem_cache_alloc+0xbb3/0x11c0 mm/slub.c:3264 sk_prot_alloc+0xeb/0x570 net/core/sock.c:1914 sk_clone_lock+0xd6/0x1940 net/core/sock.c:2118 inet_csk_clone_lock+0x8d/0x6a0 net/ipv4/inet_connection_sock.c:956 tcp_create_openreq_child+0xb1/0x1ef0 net/ipv4/tcp_minisocks.c:453 tcp_v4_syn_recv_sock+0x268/0x2710 net/ipv4/tcp_ipv4.c:1563 tcp_check_req+0x207c/0x2a30 net/ipv4/tcp_minisocks.c:765 tcp_v4_rcv+0x36f5/0x4ed0 net/ipv4/tcp_ipv4.c:2047 ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline] ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609 ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5505 [inline] __netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553 __netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605 netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696 gro_normal_list net/core/dev.c:5850 [inline] napi_complete_done+0x579/0xdd0 net/core/dev.c:6587 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x824/0x1880 net/core/dev.c:7174 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558 Fixes: 342159ee394d ("net: avoid dirtying sk->sk_rx_queue_mapping") Fixes: a37a0ee4d25c ("net: avoid uninit-value from tcp_conn_request") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Tested-by: Alexander Potapenko <glider@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-02net: avoid uninit-value from tcp_conn_requestEric Dumazet1-1/+1
A recent change triggers a KMSAN warning, because request sockets do not initialize @sk_rx_queue_mapping field. Add sk_rx_queue_update() helper to make our intent clear. BUG: KMSAN: uninit-value in sk_rx_queue_set include/net/sock.h:1922 [inline] BUG: KMSAN: uninit-value in tcp_conn_request+0x3bcc/0x4dc0 net/ipv4/tcp_input.c:6922 sk_rx_queue_set include/net/sock.h:1922 [inline] tcp_conn_request+0x3bcc/0x4dc0 net/ipv4/tcp_input.c:6922 tcp_v4_conn_request+0x218/0x2a0 net/ipv4/tcp_ipv4.c:1528 tcp_rcv_state_process+0x2c5/0x3290 net/ipv4/tcp_input.c:6406 tcp_v4_do_rcv+0xb4e/0x1330 net/ipv4/tcp_ipv4.c:1738 tcp_v4_rcv+0x468d/0x4ed0 net/ipv4/tcp_ipv4.c:2100 ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline] ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609 ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5505 [inline] __netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553 __netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605 netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696 gro_normal_list net/core/dev.c:5850 [inline] napi_complete_done+0x579/0xdd0 net/core/dev.c:6587 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x824/0x1880 net/core/dev.c:7174 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558 invoke_softirq+0xa4/0x130 kernel/softirq.c:432 __irq_exit_rcu kernel/softirq.c:636 [inline] irq_exit_rcu+0x76/0x130 kernel/softirq.c:648 common_interrupt+0xb6/0xd0 arch/x86/kernel/irq.c:240 asm_common_interrupt+0x1e/0x40 smap_restore arch/x86/include/asm/smap.h:67 [inline] get_shadow_origin_ptr mm/kmsan/instrumentation.c:31 [inline] __msan_metadata_ptr_for_load_1+0x28/0x30 mm/kmsan/instrumentation.c:63 tomoyo_check_acl+0x1b0/0x630 security/tomoyo/domain.c:173 tomoyo_path_permission security/tomoyo/file.c:586 [inline] tomoyo_check_open_permission+0x61f/0xe10 security/tomoyo/file.c:777 tomoyo_file_open+0x24f/0x2d0 security/tomoyo/tomoyo.c:311 security_file_open+0xb1/0x1f0 security/security.c:1635 do_dentry_open+0x4e4/0x1bf0 fs/open.c:809 vfs_open+0xaf/0xe0 fs/open.c:957 do_open fs/namei.c:3426 [inline] path_openat+0x52f1/0x5dd0 fs/namei.c:3559 do_filp_open+0x306/0x760 fs/namei.c:3586 do_sys_openat2+0x263/0x8f0 fs/open.c:1212 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x314/0x380 fs/open.c:1232 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: __alloc_pages+0xbc7/0x10a0 mm/page_alloc.c:5409 alloc_pages+0x8a5/0xb80 alloc_slab_page mm/slub.c:1810 [inline] allocate_slab+0x287/0x1c20 mm/slub.c:1947 new_slab mm/slub.c:2010 [inline] ___slab_alloc+0xbdf/0x1e90 mm/slub.c:3039 __slab_alloc mm/slub.c:3126 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3259 [inline] kmem_cache_alloc+0xbb3/0x11c0 mm/slub.c:3264 reqsk_alloc include/net/request_sock.h:91 [inline] inet_reqsk_alloc+0xaf/0x8b0 net/ipv4/tcp_input.c:6712 tcp_conn_request+0x910/0x4dc0 net/ipv4/tcp_input.c:6852 tcp_v4_conn_request+0x218/0x2a0 net/ipv4/tcp_ipv4.c:1528 tcp_rcv_state_process+0x2c5/0x3290 net/ipv4/tcp_input.c:6406 tcp_v4_do_rcv+0xb4e/0x1330 net/ipv4/tcp_ipv4.c:1738 tcp_v4_rcv+0x468d/0x4ed0 net/ipv4/tcp_ipv4.c:2100 ip_protocol_deliver_rcu+0x760/0x10b0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x584/0x8c0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:551 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:601 [inline] ip_sublist_rcv+0x11fd/0x1520 net/ipv4/ip_input.c:609 ip_list_rcv+0x95f/0x9a0 net/ipv4/ip_input.c:644 __netif_receive_skb_list_ptype net/core/dev.c:5505 [inline] __netif_receive_skb_list_core+0xe34/0x1240 net/core/dev.c:5553 __netif_receive_skb_list+0x7fc/0x960 net/core/dev.c:5605 netif_receive_skb_list_internal+0x868/0xde0 net/core/dev.c:5696 gro_normal_list net/core/dev.c:5850 [inline] napi_complete_done+0x579/0xdd0 net/core/dev.c:6587 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline] virtnet_poll+0x17b6/0x2350 drivers/net/virtio_net.c:1557 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020 napi_poll net/core/dev.c:7087 [inline] net_rx_action+0x824/0x1880 net/core/dev.c:7174 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558 Fixes: 342159ee394d ("net: avoid dirtying sk->sk_rx_queue_mapping") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Link: https://lore.kernel.org/r/20211130182939.2584764-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-26net: avoid dirtying sk->sk_napi_idEric Dumazet1-1/+2
sk_napi_id is located in a cache line that can be kept read mostly. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-01net: annotate data race around sk_ll_usecEric Dumazet1-1/+1
sk_ll_usec is read locklessly from sk_can_busy_loop() while another thread can change its value in sock_setsockopt() This is correct but needs annotations. BUG: KCSAN: data-race in __skb_try_recv_datagram / sock_setsockopt write to 0xffff88814eb5f904 of 4 bytes by task 14011 on cpu 0: sock_setsockopt+0x1287/0x2090 net/core/sock.c:1175 __sys_setsockopt+0x14f/0x200 net/socket.c:2100 __do_sys_setsockopt net/socket.c:2115 [inline] __se_sys_setsockopt net/socket.c:2112 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2112 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88814eb5f904 of 4 bytes by task 14001 on cpu 1: sk_can_busy_loop include/net/busy_poll.h:41 [inline] __skb_try_recv_datagram+0x14f/0x320 net/core/datagram.c:273 unix_dgram_recvmsg+0x14c/0x870 net/unix/af_unix.c:2101 unix_seqpacket_recvmsg+0x5a/0x70 net/unix/af_unix.c:2067 ____sys_recvmsg+0x15d/0x310 include/linux/uio.h:244 ___sys_recvmsg net/socket.c:2598 [inline] do_recvmmsg+0x35c/0x9f0 net/socket.c:2692 __sys_recvmmsg net/socket.c:2771 [inline] __do_sys_recvmmsg net/socket.c:2794 [inline] __se_sys_recvmmsg net/socket.c:2787 [inline] __x64_sys_recvmmsg+0xcf/0x150 net/socket.c:2787 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000000 -> 0x00000101 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 14001 Comm: syz-executor.3 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-12-01net, xdp, xsk: fix __sk_mark_napi_id_once napi_id errorDaniel Borkmann1-3/+7
Stephen reported the following build error for !CONFIG_NET_RX_BUSY_POLL built kernels: In file included from fs/select.c:32: include/net/busy_poll.h: In function 'sk_mark_napi_id_once': include/net/busy_poll.h:150:36: error: 'const struct sk_buff' has no member named 'napi_id' 150 | __sk_mark_napi_id_once_xdp(sk, skb->napi_id); | ^~ Fix it by wrapping a CONFIG_NET_RX_BUSY_POLL around the helpers. Fixes: b02e5a0ebb17 ("xsk: Propagate napi_id to XDP socket Rx path") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Björn Töpel <bjorn.topel@intel.com> Link: https://lore.kernel.org/linux-next/20201201190746.7d3357fb@canb.auug.org.au
2020-12-01xsk: Propagate napi_id to XDP socket Rx pathBjörn Töpel1-4/+15
Add napi_id to the xdp_rxq_info structure, and make sure the XDP socket pick up the napi_id in the Rx path. The napi_id is used to find the corresponding NAPI structure for socket busy polling. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Tariq Toukan <tariqt@nvidia.com> Link: https://lore.kernel.org/bpf/20201130185205.196029-7-bjorn.topel@gmail.com
2020-12-01net: Add SO_BUSY_POLL_BUDGET socket optionBjörn Töpel1-2/+5
This option lets a user set a per socket NAPI budget for busy-polling. If the options is not set, it will use the default of 8. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/20201130185205.196029-3-bjorn.topel@gmail.com
2020-12-01net: Introduce preferred busy-pollingBjörn Töpel1-2/+3
The existing busy-polling mode, enabled by the SO_BUSY_POLL socket option or system-wide using the /proc/sys/net/core/busy_read knob, is an opportunistic. That means that if the NAPI context is not scheduled, it will poll it. If, after busy-polling, the budget is exceeded the busy-polling logic will schedule the NAPI onto the regular softirq handling. One implication of the behavior above is that a busy/heavy loaded NAPI context will never enter/allow for busy-polling. Some applications prefer that most NAPI processing would be done by busy-polling. This series adds a new socket option, SO_PREFER_BUSY_POLL, that works in concert with the napi_defer_hard_irqs and gro_flush_timeout knobs. The napi_defer_hard_irqs and gro_flush_timeout knobs were introduced in commit 6f8b12d661d0 ("net: napi: add hard irqs deferral feature"), and allows for a user to defer interrupts to be enabled and instead schedule the NAPI context from a watchdog timer. When a user enables the SO_PREFER_BUSY_POLL, again with the other knobs enabled, and the NAPI context is being processed by a softirq, the softirq NAPI processing will exit early to allow the busy-polling to be performed. If the application stops performing busy-polling via a system call, the watchdog timer defined by gro_flush_timeout will timeout, and regular softirq handling will resume. In summary; Heavy traffic applications that prefer busy-polling over softirq processing should use this option. Example usage: $ echo 2 | sudo tee /sys/class/net/ens785f1/napi_defer_hard_irqs $ echo 200000 | sudo tee /sys/class/net/ens785f1/gro_flush_timeout Note that the timeout should be larger than the userspace processing window, otherwise the watchdog will timeout and fall back to regular softirq processing. Enable the SO_BUSY_POLL/SO_PREFER_BUSY_POLL options on your socket. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/20201130185205.196029-2-bjorn.topel@gmail.com
2020-06-21net: Avoid overwriting valid skb->napi_idAmritha Nambiar1-1/+5
This will be useful to allow busy poll for tunneled traffic. In case of busy poll for sessions over tunnels, the underlying physical device's queues need to be polled. Tunnels schedule NAPI either via netif_rx() for backlog queue or schedule the gro_cell_poll(). netif_rx() propagates the valid skb->napi_id to the socket. OTOH, gro_cell_poll() stamps the skb->napi_id again by calling skb_mark_napi_id() with the tunnel NAPI which is not a busy poll candidate. This was preventing tunneled traffic to use busy poll. A valid NAPI ID in the skb indicates it was already marked for busy poll by a NAPI driver and hence needs to be copied into the socket. Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31net: annotate lockless accesses to sk->sk_napi_idEric Dumazet1-3/+3
We already annotated most accesses to sk->sk_napi_id We missed sk_mark_napi_id() and sk_mark_napi_id_once() which might be called without socket lock held in UDP stack. KCSAN reported : BUG: KCSAN: data-race in udpv6_queue_rcv_one_skb / udpv6_queue_rcv_one_skb write to 0xffff888121c6d108 of 4 bytes by interrupt on cpu 0: sk_mark_napi_id include/net/busy_poll.h:125 [inline] __udpv6_queue_rcv_skb net/ipv6/udp.c:571 [inline] udpv6_queue_rcv_one_skb+0x70c/0xb40 net/ipv6/udp.c:672 udpv6_queue_rcv_skb+0xb5/0x400 net/ipv6/udp.c:689 udp6_unicast_rcv_skb.isra.0+0xd7/0x180 net/ipv6/udp.c:832 __udp6_lib_rcv+0x69c/0x1770 net/ipv6/udp.c:913 udpv6_rcv+0x2b/0x40 net/ipv6/udp.c:1015 ip6_protocol_deliver_rcu+0x22a/0xbe0 net/ipv6/ip6_input.c:409 ip6_input_finish+0x30/0x50 net/ipv6/ip6_input.c:450 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip6_input+0x177/0x190 net/ipv6/ip6_input.c:459 dst_input include/net/dst.h:442 [inline] ip6_rcv_finish+0x110/0x140 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ipv6_rcv+0x1a1/0x1b0 net/ipv6/ip6_input.c:284 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 write to 0xffff888121c6d108 of 4 bytes by interrupt on cpu 1: sk_mark_napi_id include/net/busy_poll.h:125 [inline] __udpv6_queue_rcv_skb net/ipv6/udp.c:571 [inline] udpv6_queue_rcv_one_skb+0x70c/0xb40 net/ipv6/udp.c:672 udpv6_queue_rcv_skb+0xb5/0x400 net/ipv6/udp.c:689 udp6_unicast_rcv_skb.isra.0+0xd7/0x180 net/ipv6/udp.c:832 __udp6_lib_rcv+0x69c/0x1770 net/ipv6/udp.c:913 udpv6_rcv+0x2b/0x40 net/ipv6/udp.c:1015 ip6_protocol_deliver_rcu+0x22a/0xbe0 net/ipv6/ip6_input.c:409 ip6_input_finish+0x30/0x50 net/ipv6/ip6_input.c:450 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip6_input+0x177/0x190 net/ipv6/ip6_input.c:459 dst_input include/net/dst.h:442 [inline] ip6_rcv_finish+0x110/0x140 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ipv6_rcv+0x1a1/0x1b0 net/ipv6/ip6_input.c:284 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 10890 Comm: syz-executor.0 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: e68b6e50fa35 ("udp: enable busy polling for all sockets") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 335Thomas Gleixner1-13/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin st fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 111 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.567572064@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-30net: remove sock_poll_busy_flagChristoph Hellwig1-6/+0
Fold it into the only caller to make the code simpler and easier to read. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-30net: remove sock_poll_busy_loopChristoph Hellwig1-9/+0
There is no point in hiding this logic in a helper. Also remove the useless events != 0 check and only busy loop once we know we actually have a poll method. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-02net: Record receive queue number for a connectionAmritha Nambiar1-0/+1
This patch adds a new field to sock_common 'skc_rx_queue_mapping' which holds the receive queue number for the connection. The Rx queue is marked in tcp_finish_connect() to allow a client app to do SO_INCOMING_NAPI_ID after a connect() call to get the right queue association for a socket. Rx queue is also marked in tcp_conn_request() to allow syn-ack to go on the right tx-queue associated with the queue on which syn is received. Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com> Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-26net: refactor socket_pollChristoph Hellwig1-0/+15
Factor out two busy poll related helpers for late reuse, and remove a command that isn't very helpful, especially with the __poll_t annotations in place. Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-12net: fix compilation when busy poll is not enabledDaniel Borkmann1-6/+6
MIN_NAPI_ID is used in various places outside of CONFIG_NET_RX_BUSY_POLL wrapping, so when it's not set we run into build errors such as: net/core/dev.c: In function 'dev_get_by_napi_id': net/core/dev.c:886:16: error: ‘MIN_NAPI_ID’ undeclared (first use in this function) if (napi_id < MIN_NAPI_ID) ^~~~~~~~~~~ Thus, have MIN_NAPI_ID always defined to fix these errors. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-25net: Commonize busy polling code to focus on napi_id instead of socketSridhar Samudrala1-5/+15
Move the core functionality in sk_busy_loop() to napi_busy_loop() and make it independent of sk. This enables re-using this function in epoll busy loop implementation. Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-25net: Track start of busy loop instead of when it should endAlexander Duyck1-30/+38
This patch flips the logic we were using to determine if the busy polling has timed out. The main motivation for this is that we will need to support two different possible timeout values in the future and by recording the start time rather than when we would want to end we can focus on making the end_time specific to the task be it epoll or socket based polling. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-25net: Change return type of sk_busy_loop from bool to voidAlexander Duyck1-3/+2
checking the return value of sk_busy_loop. As there are only a few consumers of that data, and the data being checked for can be replaced with a check for !skb_queue_empty() we might as well just pull the code out of sk_busy_loop and place it in the spots that actually need it. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-25net: Only define skb_mark_napi_id in one spot instead of twoAlexander Duyck1-13/+9
Instead of defining two versions of skb_mark_napi_id I think it is more readable to just match the format of the sk_mark_napi_id functions and just wrap the contents of the function instead of defining two versions of the function. This way we can save a few lines of code since we only need 2 of the ifdef/endif but needed 5 for the extra function declaration. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-25net: Busy polling should ignore sender CPUsAlexander Duyck1-2/+7
This patch is a cleanup/fix for NAPI IDs following the changes that made it so that sender_cpu and napi_id were doing a better job of sharing the same location in the sk_buff. One issue I found is that we weren't validating the napi_id as being valid before we started trying to setup the busy polling. This change corrects that by using the MIN_NAPI_ID value that is now used in both allocating the NAPI IDs, as well as validating them. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar1-0/+1
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/clock.h> We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which will have to be picked up from other headers and .c files. Create a trivial placeholder <linux/sched/clock.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-14net: busy-poll: remove LL_FLUSH_FAILED and LL_FLUSH_BUSYEric Dumazet1-4/+0
Commit 79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") made them obsolete. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18udp: enable busy polling for all socketsEric Dumazet1-9/+19
UDP busy polling is restricted to connected UDP sockets. This is because sk_busy_loop() only takes care of one NAPI context. There are cases where it could be extended. 1) Some hosts receive traffic on a single NIC, with one RX queue. 2) Some applications use SO_REUSEPORT and associated BPF filter to split the incoming traffic on one UDP socket per RX queue/thread/cpu 3) Some UDP sockets are used to send/receive traffic for one flow, but they do not bother with connect() This patch records the napi_id of first received skb, giving more reach to busy polling. Tested: lpaa23:~# echo 70 >/proc/sys/net/core/busy_read lpaa24:~# echo 70 >/proc/sys/net/core/busy_read lpaa23:~# for f in `seq 1 10`; do ./super_netperf 1 -H lpaa24 -t UDP_RR -l 5; done Before patch : 27867 28870 37324 41060 41215 36764 36838 44455 41282 43843 After patch : 73920 73213 70147 74845 71697 68315 68028 75219 70082 73707 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16net: busy-poll: remove need_resched() from sk_can_busy_loop()Eric Dumazet1-3/+2
Now sk_busy_loop() can schedule by itself, we can remove need_resched() check from sk_can_busy_loop() Also add a const to its struct sock parameter. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Adam Belay <abelay@google.com> Cc: Tariq Toukan <tariqt@mellanox.com> Cc: Yuval Mintz <Yuval.Mintz@cavium.com> Cc: Ariel Elior <ariel.elior@cavium.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-19net: un-inline sk_busy_loop()Eric Dumazet1-44/+1
There is really little gain from inlining this big function. We'll soon make it even bigger in following patches. This means we no longer need to export napi_by_id() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13sched, net: Fixup busy_loop_us_clock()Peter Zijlstra1-18/+1
The only valid use of preempt_enable_no_resched() is if the very next line is schedule() or if we know preemption cannot actually be enabled by that statement due to known more preempt_count 'refs'. This busy_poll stuff looks to be completely and utterly broken, sched_clock() can return utter garbage with interrupts enabled (rare but still) and it can drift unbounded between CPUs. This means that if you get preempted/migrated and your new CPU is years behind on the previous CPU we get to busy spin for a _very_ long time. There is a _REASON_ sched_clock() warns about preemptability - papering over it with a preempt_disable()/preempt_enable_no_resched() is just terminal brain damage on so many levels. Replace sched_clock() usage with local_clock() which has a bounded drift between CPUs (<2 jiffies). There is a further problem with the entire busy wait poll thing in that the spin time is additive to the syscall timeout, not inclusive. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: rui.zhang@intel.com Cc: jacob.jun.pan@linux.intel.com Cc: Mike Galbraith <bitbucket@online.de> Cc: hpa@zytor.com Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: lenb@kernel.org Cc: rjw@rjwysocki.net Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20131119151338.GF3694@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-29net: add cpu_relax to busy poll loopEliezer Tamir1-0/+1
Add a cpu_relaxt to sk_busy_loop. Julie Cummings reported performance issues when hyperthreading is on. Arjan van de Ven observed that we should have a cpu_relax() in the busy poll loop. Reported-by: Julie Cummings <julie.a.cummings@intel.com> Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09net: rename busy poll MIB counterEliezer Tamir1-1/+1
Rename mib counter from "low latency" to "busy poll" v1 also moved the counter to the ip MIB (suggested by Shawn Bohrer) Eric Dumazet suggested that the current location is better. So v2 just renames the counter to fit the new naming convention. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-05busy_poll: cleanup do-nothing placeholdersEliezer Tamir1-5/+0
When renaming ll_poll to busy poll, I introduced a typo in the name of the do-nothing placeholder for sk_busy_loop and called it sk_busy_poll. This broke compile when busy poll was not configured. Cong Wang submitted a patch to fixed that. This patch removes the now redundant, misspelled placeholder. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-02net: rename CONFIG_NET_LL_RX_POLL to CONFIG_NET_RX_BUSY_POLLCong Wang1-3/+3
Eliezer renames several *ll_poll to *busy_poll, but forgets CONFIG_NET_LL_RX_POLL, so in case of confusion, rename it too. Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-02net: fix a compile error when CONFIG_NET_LL_RX_POLL is not setCong Wang1-0/+5
When CONFIG_NET_LL_RX_POLL is not set, I got: net/socket.c: In function ‘sock_poll’: net/socket.c:1165:4: error: implicit declaration of function ‘sk_busy_loop’ [-Werror=implicit-function-declaration] Fix this by adding a nop when !CONFIG_NET_LL_RX_POLL. Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-11net: rename busy poll socket op and globalsEliezer Tamir1-4/+4
Rename LL_SO to BUSY_POLL_SO Rename sysctl_net_ll_{read,poll} to sysctl_busy_{read,poll} Fix up users of these variables. Fix documentation for sysctl. a patch for the socket.7 man page will follow separately, because of limitations of my mail setup. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-11net: rename ll methods to busy-pollEliezer Tamir1-10/+12
Rename ndo_ll_poll to ndo_busy_poll. Rename sk_mark_ll to sk_mark_napi_id. Rename skb_mark_ll to skb_mark_napi_id. Correct all useres of these functions. Update comments and defines in include/net/busy_poll.h Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-11net: rename include/net/ll_poll.h to include/net/busy_poll.hEliezer Tamir1-0/+183
Rename the file and correct all the places where it is included. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>