================================================================== BUG: KCSAN: data-race in pcpu_alloc / pcpu_free_area write to 0xffffffff8454374c of 4 bytes by task 1754 on cpu 1: pcpu_update_empty_pages mm/percpu.c:559 [inline] pcpu_block_update_hint_free mm/percpu.c:994 [inline] pcpu_free_area+0x531/0x5e0 mm/percpu.c:1254 free_percpu+0x1d2/0x690 mm/percpu.c:2102 xt_percpu_counter_free+0x5f/0x70 net/netfilter/x_tables.c:1855 cleanup_entry+0x170/0x1a0 net/ipv6/netfilter/ip6_tables.c:672 __do_replace+0x46e/0x590 net/ipv6/netfilter/ip6_tables.c:1101 do_replace net/ipv6/netfilter/ip6_tables.c:1156 [inline] do_ip6t_set_ctl+0x6b5/0x16d0 net/ipv6/netfilter/ip6_tables.c:1638 nf_setsockopt+0x1a6/0x1c0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x1ae3/0x33e0 net/ipv6/ipv6_sockglue.c:1008 tcp_setsockopt+0x8c/0xa0 net/ipv4/tcp.c:3643 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3257 __sys_setsockopt+0x18f/0x200 net/socket.c:2117 __do_sys_setsockopt net/socket.c:2128 [inline] __se_sys_setsockopt net/socket.c:2125 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2125 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffffffff8454374c of 4 bytes by task 1761 on cpu 0: pcpu_alloc+0x9d6/0x1170 mm/percpu.c:1835 __alloc_percpu+0x20/0x30 mm/percpu.c:1907 xt_percpu_counter_alloc+0x6b/0x110 net/netfilter/x_tables.c:1835 find_check_entry net/ipv6/netfilter/ip6_tables.c:546 [inline] translate_table+0x9f2/0x1070 net/ipv6/netfilter/ip6_tables.c:734 do_replace net/ipv6/netfilter/ip6_tables.c:1152 [inline] do_ip6t_set_ctl+0x668/0x16d0 net/ipv6/netfilter/ip6_tables.c:1638 nf_setsockopt+0x1a6/0x1c0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x1ae3/0x33e0 net/ipv6/ipv6_sockglue.c:1008 tcp_setsockopt+0x8c/0xa0 net/ipv4/tcp.c:3643 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3257 __sys_setsockopt+0x18f/0x200 net/socket.c:2117 __do_sys_setsockopt net/socket.c:2128 [inline] __se_sys_setsockopt net/socket.c:2125 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2125 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 1761 Comm: syz-executor.4 Not tainted 5.12.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================