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BUG: KCSAN: data-race in __bpf_get_stackid / __bpf_get_stackid

write to 0xffff88810d2bc30c of 4 bytes by task 9429 on cpu 0:
 __bpf_get_stackid+0x77a/0x800 kernel/bpf/stackmap.c:292
 ____bpf_get_stackid kernel/bpf/stackmap.c:324 [inline]
 bpf_get_stackid+0xee/0x120 kernel/bpf/stackmap.c:300
 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1810 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1799
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1332 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2298
 __traceiter_kfree+0x2e/0x50 include/trace/events/kmem.h:94
 __do_trace_kfree include/trace/events/kmem.h:94 [inline]
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x27b/0x320 mm/slub.c:4866
 netlbl_secattr_free include/net/netlabel.h:400 [inline]
 selinux_netlbl_sk_security_free+0x18b/0x1d0 security/selinux/netlabel.c:162
 selinux_sk_free_security+0x3b/0x50 security/selinux/hooks.c:5415
 security_sk_free+0x65/0x80 security/security.c:4903
 sk_prot_free net/core/sock.c:2271 [inline]
 __sk_destruct+0x392/0x4c0 net/core/sock.c:2373
 sk_destruct net/core/sock.c:2401 [inline]
 __sk_free+0x227/0x270 net/core/sock.c:2412
 sk_free net/core/sock.c:2423 [inline]
 sock_put include/net/sock.h:1960 [inline]
 sk_common_release+0x169/0x220 net/core/sock.c:3960
 udp_lib_close+0x15/0x20 include/net/udp.h:311
 inet_release+0xce/0xf0 net/ipv4/af_inet.c:435
 __sock_release net/socket.c:649 [inline]
 sock_close+0x68/0x150 net/socket.c:1439
 __fput+0x298/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810d2bc30c of 4 bytes by task 9420 on cpu 1:
 __bpf_get_stackid+0x33a/0x800 kernel/bpf/stackmap.c:278
 ____bpf_get_stackid kernel/bpf/stackmap.c:324 [inline]
 bpf_get_stackid+0xee/0x120 kernel/bpf/stackmap.c:300
 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1810 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1799
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1332 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2298
 __traceiter_kfree+0x2e/0x50 include/trace/events/kmem.h:94
 __do_trace_kfree include/trace/events/kmem.h:94 [inline]
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x27b/0x320 mm/slub.c:4866
 ___sys_recvmsg+0x135/0x370 net/socket.c:2877
 do_recvmmsg+0x1ef/0x540 net/socket.c:2971
 __sys_recvmmsg net/socket.c:3045 [inline]
 __do_sys_recvmmsg net/socket.c:3068 [inline]
 __se_sys_recvmmsg net/socket.c:3061 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3061
 x64_sys_call+0x27a6/0x2ff0 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: 0x0000000b -> 0x00000014

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 9420 Comm: syz.5.2083 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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