syzbot

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BUG: KCSAN: data-race in __release_sock / __sk_receive_skb

write to 0xffff88806feeb12c of 4 bytes by task 14065 on cpu 0:
 __release_sock+0x17b/0x1e0 net/core/sock.c:2451
 release_sock+0x61/0x160 net/core/sock.c:2953
 dccp_close+0x474/0x8e0 net/dccp/proto.c:1067
 inet_release+0x86/0x100 net/ipv4/af_inet.c:427
 inet6_release+0x4a/0x70 net/ipv6/af_inet6.c:470
 __sock_release+0x85/0x160 net/socket.c:592
 sock_close+0x24/0x30 net/socket.c:1270
 __fput+0x1e1/0x520 fs/file_table.c:280
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:164
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
 do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88806feeb12c of 4 bytes by interrupt on cpu 1:
 sk_rcvqueues_full include/net/sock.h:917 [inline]
 __sk_receive_skb+0xf3/0x580 net/core/sock.c:505
 dccp_v6_rcv+0x92a/0xea2 net/dccp/ipv6.c:775
 ip6_protocol_deliver_rcu+0x22a/0xbe0 net/ipv6/ip6_input.c:432
 ip6_input_finish+0x30/0x50 net/ipv6/ip6_input.c:473
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_input+0x177/0x190 net/ipv6/ip6_input.c:482
 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:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0x1a1/0x1b0 net/ipv6/ip6_input.c:306
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5150
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5264
 process_backlog+0x207/0x4b0 net/core/dev.c:6095
 napi_poll net/core/dev.c:6532 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6600
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:706 [inline]
 ip6_finish_output2+0x730/0xf60 net/ipv6/ip6_output.c:117
 __ip6_finish_output net/ipv6/ip6_output.c:142 [inline]
 __ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127
 ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x108/0x290 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_xmit+0x6cb/0xcd0 net/ipv6/ip6_output.c:279
 inet6_csk_xmit+0x170/0x1f0 net/ipv6/inet6_connection_sock.c:135
 dccp_transmit_skb+0x5a2/0x940 net/dccp/output.c:138
 dccp_xmit_packet+0xfc/0x3b0 net/dccp/output.c:277
 dccp_write_xmit+0x14b/0x170 net/dccp/output.c:359
 dccp_sendmsg+0x70b/0x7b0 net/dccp/proto.c:812
 inet_sendmsg+0x6d/0x90 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:659
 ____sys_sendmsg+0x212/0x4d0 net/socket.c:2330
 ___sys_sendmsg+0xb5/0x100 net/socket.c:2384
 __sys_sendmmsg+0x123/0x350 net/socket.c:2474
 __do_sys_sendmmsg net/socket.c:2503 [inline]
 __se_sys_sendmmsg net/socket.c:2500 [inline]
 __x64_sys_sendmmsg+0x64/0x80 net/socket.c:2500
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 14067 Comm: syz-executor.1 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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