================================================================== BUG: KCSAN: data-race in ip_finish_output2 / ip_finish_output2 write to 0xffff8880a55a4a18 of 8 bytes by interrupt on cpu 1: sock_confirm_neigh include/net/sock.h:1955 [inline] ip_finish_output2+0x3d6/0xe40 net/ipv4/ip_output.c:226 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x23a/0x490 net/ipv4/ip_output.c:290 ip_finish_output+0x41/0x160 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0xdf/0x210 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out+0x74/0x90 net/ipv4/ip_output.c:125 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532 sctp_v4_xmit+0xf4/0x110 net/sctp/protocol.c:976 sctp_packet_transmit+0x111b/0x1760 net/sctp/output.c:629 sctp_outq_flush_transports net/sctp/outqueue.c:1146 [inline] sctp_outq_flush+0x1e9/0x14c0 net/sctp/outqueue.c:1194 sctp_outq_uncork+0x64/0x80 net/sctp/outqueue.c:757 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1781 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1184 [inline] sctp_do_sm+0x36a/0x2ef0 net/sctp/sm_sideeffect.c:1155 sctp_generate_heartbeat_event+0x137/0x200 net/sctp/sm_sideeffect.c:391 call_timer_fn+0x5f/0x2f0 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0xc0c/0xcd0 kernel/time/timer.c:1786 __do_softirq+0x115/0x33f kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xbb/0xe0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1af/0x280 kernel/sched/idle.c:263 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355 start_secondary+0x168/0x1b0 arch/x86/kernel/smpboot.c:264 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 read to 0xffff8880a55a4a18 of 8 bytes by interrupt on cpu 0: sock_confirm_neigh include/net/sock.h:1954 [inline] ip_finish_output2+0x3ab/0xe40 net/ipv4/ip_output.c:226 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x23a/0x490 net/ipv4/ip_output.c:290 ip_finish_output+0x41/0x160 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0xdf/0x210 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out+0x74/0x90 net/ipv4/ip_output.c:125 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532 sctp_v4_xmit+0xf4/0x110 net/sctp/protocol.c:976 sctp_packet_transmit+0x111b/0x1760 net/sctp/output.c:629 sctp_outq_flush_transports net/sctp/outqueue.c:1146 [inline] sctp_outq_flush+0x1e9/0x14c0 net/sctp/outqueue.c:1194 sctp_outq_uncork+0x64/0x80 net/sctp/outqueue.c:757 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1781 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1184 [inline] sctp_do_sm+0x36a/0x2ef0 net/sctp/sm_sideeffect.c:1155 sctp_generate_heartbeat_event+0x137/0x200 net/sctp/sm_sideeffect.c:391 call_timer_fn+0x5f/0x2f0 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0xc0c/0xcd0 kernel/time/timer.c:1786 __do_softirq+0x115/0x33f kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xbb/0xe0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1af/0x280 kernel/sched/idle.c:263 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355 rest_init+0xec/0xf6 init/main.c:452 arch_call_rest_init+0x17/0x37 start_kernel+0x838/0x85e init/main.c:786 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:490 x86_64_start_kernel+0x72/0x76 arch/x86/kernel/head64.c:471 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================