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BUG: KCSAN: data-race in hash_ipport4_add / hash_ipport4_head

read-write to 0xffff88811b914878 of 8 bytes by task 6960 on cpu 1:
 hash_ipport4_add+0x6fa/0x1060 net/netfilter/ipset/ip_set_hash_gen.h:-1
 hash_ipport4_uadt+0x771/0x8b0 net/netfilter/ipset/ip_set_hash_ipport.c:199
 call_ad+0x231/0x640 net/netfilter/ipset/ip_set_core.c:1752
 ip_set_ad+0x5b1/0x680 net/netfilter/ipset/ip_set_core.c:1842
 ip_set_uadd+0x41/0x50 net/netfilter/ipset/ip_set_core.c:1865
 nfnetlink_rcv_msg+0x4e2/0x5b0 net/netfilter/nfnetlink.c:300
 netlink_rcv_skb+0x11e/0x220 net/netlink/af_netlink.c:2556
 nfnetlink_rcv+0x15f/0x1740 net/netfilter/nfnetlink.c:667
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x5a7/0x680 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x5be/0x6f0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x532/0x580 net/socket.c:2684
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2773
 x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811b914878 of 8 bytes by task 6964 on cpu 0:
 hash_ipport4_ext_size net/netfilter/ipset/ip_set_hash_gen.h:836 [inline]
 hash_ipport4_head+0x341/0x900 net/netfilter/ipset/ip_set_hash_gen.h:1290
 ip_set_dump_do+0xa37/0xad0 net/netfilter/ipset/ip_set_core.c:1654
 netlink_dump+0x452/0x870 net/netlink/af_netlink.c:2331
 netlink_recvmsg+0x420/0x550 net/netlink/af_netlink.c:1982
 sock_recvmsg_nosec net/socket.c:1126 [inline]
 sock_recvmsg+0xf5/0x120 net/socket.c:1148
 ____sys_recvmsg+0xf5/0x280 net/socket.c:2904
 ___sys_recvmsg+0x11f/0x3a0 net/socket.c:2946
 do_recvmmsg+0x1e5/0x560 net/socket.c:3041
 __sys_recvmmsg net/socket.c:3115 [inline]
 __do_sys_recvmmsg net/socket.c:3138 [inline]
 __se_sys_recvmmsg net/socket.c:3131 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3131
 x64_sys_call+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000000000e880 -> 0x000000000000e940

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6964 Comm: syz.4.781 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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