==================================================================
BUG: KCSAN: data-race in __bpf_get_stackid / bcmp

write to 0xffffc9000f8b4ab0 of 224 bytes by task 11432 on cpu 1:
 __bpf_get_stackid+0x761/0x800 kernel/bpf/stackmap.c:288
 ____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_run4+0x114/0x1d0 kernel/trace/bpf_trace.c:2301
 __traceiter_sched_switch+0x3c/0x60 include/trace/events/sched.h:220
 __do_trace_sched_switch include/trace/events/sched.h:220 [inline]
 trace_sched_switch include/trace/events/sched.h:220 [inline]
 __schedule+0xa1f/0xb30 kernel/sched/core.c:6787
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x5f/0xd0 kernel/sched/core.c:6883
 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:6940
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x414/0xa50 kernel/locking/mutex.c:747
 __mutex_lock_slowpath+0xa/0x10 kernel/locking/mutex.c:1035
 mutex_lock+0x27/0x30 kernel/locking/mutex.c:278
 exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 synchronize_rcu_expedited+0x18a/0x790 kernel/rcu/tree_exp.h:998
 synchronize_net+0x55/0x70 net/core/dev.c:11927
 netif_napi_del include/linux/netdevice.h:2900 [inline]
 peer_remove_after_dead+0xdf/0x200 drivers/net/wireguard/peer.c:124
 wg_peer_remove+0x100/0x120 drivers/net/wireguard/peer.c:164
 wg_set_device+0x4a0/0x12e0 drivers/net/wireguard/netlink.c:570
 genl_family_rcv_msg_doit+0x140/0x1b0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x422/0x460 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2551
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5a5/0x680 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x58b/0x6b0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x142/0x180 net/socket.c:727
 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2566
 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2620
 __sys_sendmsg net/socket.c:2652 [inline]
 __do_sys_sendmsg net/socket.c:2657 [inline]
 __se_sys_sendmsg net/socket.c:2655 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2655
 x64_sys_call+0x2999/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:47
 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 0xffffc9000f8b4ae8 of 8 bytes by task 3368 on cpu 0:
 memcmp lib/string.c:683 [inline]
 bcmp+0x23/0x90 lib/string.c:715
 memcmp include/linux/fortify-string.h:727 [inline]
 __bpf_get_stackid+0x371/0x800 kernel/bpf/stackmap.c:279
 ____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_run4+0x114/0x1d0 kernel/trace/bpf_trace.c:2301
 __traceiter_sched_switch+0x3c/0x60 include/trace/events/sched.h:220
 __do_trace_sched_switch include/trace/events/sched.h:220 [inline]
 trace_sched_switch include/trace/events/sched.h:220 [inline]
 __schedule+0xa1f/0xb30 kernel/sched/core.c:6787
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x5f/0xd0 kernel/sched/core.c:6883
 worker_thread+0x668/0x770 kernel/workqueue.c:3417
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0xffffffff813eac19 -> 0xffffffff85630b24

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3368 Comm: kworker/0:2 Not tainted 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue:  0x0 (events)
==================================================================