netdevsim netdevsim2 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim2 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
==================================================================
BUG: KCSAN: data-race in pcpu_alloc / pcpu_block_update_hint_alloc

read-write to 0xffffffff883da4dc of 4 bytes by task 3097 on cpu 1:
 pcpu_update_empty_pages mm/percpu.c:602 [inline]
 pcpu_block_update_hint_alloc+0x5db/0x6a0 mm/percpu.c:923
 pcpu_alloc_area+0x49f/0x4d0 mm/percpu.c:1258
 pcpu_alloc+0x4b3/0x10d0 mm/percpu.c:1808
 __alloc_percpu+0x24/0x30 mm/percpu.c:1943
 xt_percpu_counter_alloc+0x72/0x110 net/netfilter/x_tables.c:1931
 find_check_entry net/ipv4/netfilter/ip_tables.c:526 [inline]
 translate_table+0x921/0xf70 net/ipv4/netfilter/ip_tables.c:716
 ipt_register_table+0x9a/0x430 net/ipv4/netfilter/ip_tables.c:1734
 iptable_nat_table_init+0x42/0x290 net/ipv4/netfilter/iptable_nat.c:115
 xt_find_table_lock+0x194/0x260 net/netfilter/x_tables.c:1260
 xt_request_find_table_lock+0x26/0xa0 net/netfilter/x_tables.c:1285
 get_info net/ipv4/netfilter/ip_tables.c:963 [inline]
 do_ipt_get_ctl+0x554/0xbe0 net/ipv4/netfilter/ip_tables.c:1651
 nf_getsockopt+0x18c/0x1b0 net/netfilter/nf_sockopt.c:116
 ip_getsockopt+0x12a/0x170 net/ipv4/ip_sockglue.c:1777
 tcp_getsockopt+0xaa/0xe0 net/ipv4/tcp.c:4375
 sock_common_getsockopt+0x5b/0x70 net/core/sock.c:3700
 do_sock_getsockopt+0x121/0x1a0 net/socket.c:2373
 __sys_getsockopt+0x19a/0x210 net/socket.c:2402
 __do_sys_getsockopt net/socket.c:2412 [inline]
 __se_sys_getsockopt net/socket.c:2409 [inline]
 __x64_sys_getsockopt+0x66/0x80 net/socket.c:2409
 do_syscall_64+0xd3/0x1d0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

read to 0xffffffff883da4dc of 4 bytes by task 3123 on cpu 0:
 pcpu_alloc+0x9aa/0x10d0 mm/percpu.c:1868
 __alloc_percpu_gfp+0x26/0x30 mm/percpu.c:1930
 fib_nh_common_init+0x48/0x2b0 net/ipv4/fib_semantics.c:591
 fib6_nh_init+0xdc3/0x15c0 net/ipv6/route.c:3620
 ip6_route_info_create+0x7b7/0xba0 net/ipv6/route.c:3807
 addrconf_f6i_alloc+0x188/0x280 net/ipv6/route.c:4583
 ipv6_add_addr+0x3c8/0x820 net/ipv6/addrconf.c:1119
 inet6_addr_add+0x3ff/0x660 net/ipv6/addrconf.c:3057
 inet6_rtm_newaddr+0x4c4/0x590 net/ipv6/addrconf.c:5045
 rtnetlink_rcv_msg+0x82e/0x8e0 net/core/rtnetlink.c:6595
 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2559
 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6613
 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
 netlink_unicast+0x58d/0x660 net/netlink/af_netlink.c:1361
 netlink_sendmsg+0x5d3/0x6e0 net/netlink/af_netlink.c:1905
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x140/0x180 net/socket.c:745
 __sys_sendto+0x1e5/0x260 net/socket.c:2191
 __do_sys_sendto net/socket.c:2203 [inline]
 __se_sys_sendto net/socket.c:2199 [inline]
 __x64_sys_sendto+0x78/0x90 net/socket.c:2199
 do_syscall_64+0xd3/0x1d0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

value changed: 0x00000002 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3123 Comm: syz-executor.2 Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================
EXT4-fs (loop2): unmounting filesystem 00000000-0000-0000-0000-000000000000.