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BUG: KCSAN: data-race in __bpf_get_stackid / __bpf_get_stackid

write to 0xffff88810b91218c of 4 bytes by task 3359 on cpu 1:
 __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:1811 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1800
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [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:2258 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2299
 __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:4829
 __bpf_prog_free+0x43/0xa0 kernel/bpf/core.c:282
 bpf_prog_unlock_free include/linux/filter.h:1100 [inline]
 bpf_jit_free+0x27c/0x310 arch/x86/net/bpf_jit_comp.c:3817
 bpf_prog_free_deferred+0x401/0x450 kernel/bpf/core.c:2891
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3321
 worker_thread+0x582/0x770 kernel/workqueue.c:3402
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xdd/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88810b91218c of 4 bytes by task 6147 on cpu 0:
 __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:1811 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1800
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [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:2258 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2299
 __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:4829
 ___sys_recvmsg+0x135/0x370 net/socket.c:2875
 do_recvmmsg+0x1ef/0x540 net/socket.c:2969
 __sys_recvmmsg net/socket.c:3043 [inline]
 __do_sys_recvmmsg net/socket.c:3066 [inline]
 __se_sys_recvmmsg net/socket.c:3059 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3059
 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: 0x0000000a -> 0x0000000c

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6147 Comm: syz.4.930 Not tainted 6.16.0-syzkaller-01056-gae388edd4a8f #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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