================================================================== BUG: KCSAN: data-race in pcpu_alloc / pcpu_block_update_hint_alloc read-write to 0xffffffff884054dc of 4 bytes by task 17077 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_gfp+0x26/0x30 mm/percpu.c:1930 bpf_map_alloc_percpu+0xab/0x200 kernel/bpf/syscall.c:466 prealloc_init+0x19f/0x470 kernel/bpf/hashtab.c:338 htab_map_alloc+0x637/0x8f0 kernel/bpf/hashtab.c:573 map_create+0x83c/0xb90 kernel/bpf/syscall.c:1320 __sys_bpf+0x667/0x7a0 kernel/bpf/syscall.c:5642 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5765 x64_sys_call+0x86c/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff884054dc of 4 bytes by task 17086 on cpu 0: pcpu_alloc+0x9aa/0x10d0 mm/percpu.c:1868 __alloc_percpu+0x24/0x30 mm/percpu.c:1943 mpls_add_dev net/mpls/af_mpls.c:1465 [inline] mpls_dev_notify+0x182/0x8f0 net/mpls/af_mpls.c:1618 notifier_call_chain kernel/notifier.c:93 [inline] raw_notifier_call_chain+0x6f/0x1d0 kernel/notifier.c:461 call_netdevice_notifiers_info+0xae/0x100 net/core/dev.c:1950 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline] call_netdevice_notifiers net/core/dev.c:2002 [inline] register_netdevice+0xc63/0xde0 net/core/dev.c:10316 register_netdev+0x3b/0x50 net/core/dev.c:10413 ip6gre_init_net+0x1d9/0x250 net/ipv6/ip6_gre.c:1625 ops_init+0x201/0x2d0 net/core/net_namespace.c:136 setup_net+0x2ea/0x7c0 net/core/net_namespace.c:340 copy_net_ns+0x389/0x520 net/core/net_namespace.c:505 create_new_namespaces+0x228/0x430 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xe6/0x120 kernel/nsproxy.c:228 ksys_unshare+0x3da/0x720 kernel/fork.c:3323 __do_sys_unshare kernel/fork.c:3394 [inline] __se_sys_unshare kernel/fork.c:3392 [inline] __x64_sys_unshare+0x1f/0x30 kernel/fork.c:3392 x64_sys_call+0x21e5/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:273 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000004 -> 0xfffffffc Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 17086 Comm: syz-executor.3 Tainted: G W 6.9.0-rc5-syzkaller-00036-g9d1ddab261f3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 ==================================================================