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BUG: KCSAN: data-race in __bpf_get_stackid / __bpf_get_stackid

write to 0xffff8881aa5c1f70 of 4 bytes by task 31412 on cpu 1:
 __bpf_get_stackid+0x76b/0x800 kernel/bpf/stackmap.c:291
 ____bpf_get_stackid kernel/bpf/stackmap.c:324 [inline]
 bpf_get_stackid+0xe9/0x120 kernel/bpf/stackmap.c:300
 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1628 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1617
 bpf_prog_53f0063d4d7f65ce+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline]
 __bpf_prog_run include/linux/filter.h:721 [inline]
 bpf_prog_run include/linux/filter.h:728 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2116
 __traceiter_kfree+0x2e/0x50 include/trace/events/kmem.h:97
 __do_trace_kfree include/trace/events/kmem.h:97 [inline]
 trace_kfree include/trace/events/kmem.h:97 [inline]
 kfree+0x351/0x400 mm/slub.c:6836
 ida_alloc_range+0x63e/0x6c0 lib/idr.c:460
 ida_alloc_max include/linux/idr.h:329 [inline]
 proc_alloc_inum fs/proc/generic.c:205 [inline]
 proc_register+0x35/0x490 fs/proc/generic.c:393
 proc_create_net_single+0xb2/0xf0 fs/proc/proc_net.c:220
 ip_vs_control_net_init+0x33f/0xe70 net/netfilter/ipvs/ip_vs_ctl.c:4456
 __ip_vs_init+0xd6/0x1d0 net/netfilter/ipvs/ip_vs_core.c:2305
 ops_init+0x22a/0x2e0 net/core/net_namespace.c:137
 setup_net+0x83/0x210 net/core/net_namespace.c:445
 copy_net_ns+0x28c/0x3b0 net/core/net_namespace.c:580
 create_new_namespaces+0x20e/0x3d0 kernel/nsproxy.c:110
 copy_namespaces+0x1ad/0x210 kernel/nsproxy.c:175
 copy_process+0xd32/0x2000 kernel/fork.c:2184
 kernel_clone+0x16c/0x5c0 kernel/fork.c:2609
 __do_sys_clone kernel/fork.c:2750 [inline]
 __se_sys_clone kernel/fork.c:2734 [inline]
 __x64_sys_clone+0xe6/0x120 kernel/fork.c:2734
 x64_sys_call+0x119c/0x3000 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881aa5c1f70 of 4 bytes by task 31399 on cpu 0:
 __bpf_get_stackid+0x287/0x800 kernel/bpf/stackmap.c:249
 ____bpf_get_stackid kernel/bpf/stackmap.c:324 [inline]
 bpf_get_stackid+0xe9/0x120 kernel/bpf/stackmap.c:300
 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1628 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1617
 bpf_prog_53f0063d4d7f65ce+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline]
 __bpf_prog_run include/linux/filter.h:721 [inline]
 bpf_prog_run include/linux/filter.h:728 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2116
 __traceiter_kfree+0x2e/0x50 include/trace/events/kmem.h:97
 __do_trace_kfree include/trace/events/kmem.h:97 [inline]
 trace_kfree include/trace/events/kmem.h:97 [inline]
 kfree+0x351/0x400 mm/slub.c:6836
 ___sys_recvmsg+0x135/0x370 net/socket.c:2893
 do_recvmmsg+0x1ef/0x540 net/socket.c:2987
 __sys_recvmmsg net/socket.c:3061 [inline]
 __do_sys_recvmmsg net/socket.c:3084 [inline]
 __se_sys_recvmmsg net/socket.c:3077 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3077
 x64_sys_call+0x27aa/0x3000 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x5b9203d0 -> 0xba7f1c2e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 31399 Comm: syz.5.9524 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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