================================================================== BUG: KCSAN: data-race in pcpu_alloc / pcpu_free_area write to 0xffffffff88f3cccc of 4 bytes by task 8390 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+0x578/0x620 mm/percpu.c:1254 free_percpu+0x1cb/0x740 mm/percpu.c:2102 xt_percpu_counter_free+0x5f/0x70 net/netfilter/x_tables.c:1861 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+0x145f/0x1710 net/ipv6/netfilter/ip6_tables.c:1636 nf_setsockopt+0x1a6/0x1c0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x1c38/0x37c0 net/ipv6/ipv6_sockglue.c:1008 tcp_setsockopt+0x8c/0xa0 net/ipv4/tcp.c:3643 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3263 __sys_setsockopt+0x2e8/0x460 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+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffffffff88f3cccc of 4 bytes by task 26158 on cpu 0: pcpu_alloc+0xaed/0x1090 mm/percpu.c:1835 __alloc_percpu_gfp+0x22/0x30 mm/percpu.c:1894 bpf_map_alloc_percpu+0xab/0x120 kernel/bpf/syscall.c:435 prealloc_init kernel/bpf/hashtab.c:296 [inline] htab_map_alloc+0x814/0xc80 kernel/bpf/hashtab.c:508 find_and_alloc_map kernel/bpf/syscall.c:122 [inline] map_create kernel/bpf/syscall.c:828 [inline] __do_sys_bpf+0x420c/0x99c0 kernel/bpf/syscall.c:4375 __se_sys_bpf kernel/bpf/syscall.c:4351 [inline] __x64_sys_bpf+0x3d/0x50 kernel/bpf/syscall.c:4351 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 26158 Comm: syz-executor.5 Tainted: G W 5.12.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================