BUG: KCSAN: data-race in data_alloc / data_push_tail

write to 0xffffffff88e3cb40 of 8 bytes by task 8594 on cpu 1:
 data_alloc+0x203/0x2b0 kernel/printk/printk_ringbuffer.c:1082
 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2475
 show_trace_log_lvl+0x52d/0x560 arch/x86/kernel/dumpstack.c:234
 __dump_stack+0x1d/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0xe8/0x140 lib/dump_stack.c:120
 dump_stack+0x15/0x1b lib/dump_stack.c:129
 fail_dump lib/fault-inject.c:73 [inline]
 should_fail_ex+0x265/0x280 lib/fault-inject.c:174
 should_fail+0xb/0x20 lib/fault-inject.c:184
 should_fail_usercopy+0x1a/0x20 lib/fault-inject-usercopy.c:37
 _inline_copy_from_user include/linux/uaccess.h:163 [inline]
 _copy_from_user+0x1c/0xb0 lib/usercopy.c:18
 copy_from_user include/linux/uaccess.h:212 [inline]
 copy_from_sockptr_offset include/linux/sockptr.h:48 [inline]
 copy_from_sockptr include/linux/sockptr.h:61 [inline]
 tipc_setsockopt+0x388/0x620 net/tipc/socket.c:3165
 do_sock_setsockopt net/socket.c:2344 [inline]
 __sys_setsockopt+0x181/0x200 net/socket.c:2369
 __do_sys_setsockopt net/socket.c:2375 [inline]
 __se_sys_setsockopt net/socket.c:2372 [inline]
 __x64_sys_setsockopt+0x64/0x80 net/socket.c:2372
 x64_sys_call+0x20ec/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:55
 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 0xffffffff88e3cb40 of 8 bytes by task 29 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0xfd/0x420 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbf/0x2b0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2475
 kauditd_printk_skb kernel/audit.c:546 [inline]
 kauditd_hold_skb+0x1b1/0x1c0 kernel/audit.c:581
 kauditd_send_queue+0x273/0x2c0 kernel/audit.c:766
 kauditd_thread+0x421/0x630 kernel/audit.c:890
 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

value changed: 0x00000000ffffe8a7 -> 0x00000000fffff6b0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 29 Comm: kauditd Not tainted 6.16.0-syzkaller-10910-g0905809b38bd #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
==================================================================
audit: type=1400 audit(1754127898.254:5862): avc:  denied  { setopt } for  pid=8592 comm="syz.0.1816" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=tipc_socket permissive=1
audit: type=1400 audit(1754127898.464:5863): avc:  denied  { create } for  pid=8599 comm="syz.4.1819" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=rawip_socket permissive=1
audit: type=1326 audit(1754127898.624:5864): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=root:sysadm_r:sysadm_t pid=8599 comm="syz.4.1819" exe="/root/syz-executor" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7fd29ec9eb69 code=0x7ffc0000
audit: type=1326 audit(1754127898.624:5865): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=root:sysadm_r:sysadm_t pid=8599 comm="syz.4.1819" exe="/root/syz-executor" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7fd29ec9eb69 code=0x7ffc0000
audit: type=1326 audit(1754127898.624:5866): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=root:sysadm_r:sysadm_t pid=8599 comm="syz.4.1819" exe="/root/syz-executor" sig=0 arch=c000003e syscall=13 compat=0 ip=0x7fd29ec9eb69 code=0x7ffc0000