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BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff88bbdcd8 of 1 bytes by task 29 on cpu 0:
 string_nocheck lib/vsprintf.c:650 [inline]
 string+0x16c/0x210 lib/vsprintf.c:728
 vsnprintf+0xa09/0xe30 lib/vsprintf.c:2803
 vscnprintf+0x42/0x90 lib/vsprintf.c:2909
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2197
 vprintk_store+0x570/0x810 kernel/printk/printk.c:2311
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2383
 vprintk_deferred kernel/printk/printk.c:4541 [inline]
 _printk_deferred+0x83/0xb0 kernel/printk/printk.c:4550
 ___ratelimit+0x294/0x2b0 lib/ratelimit.c:56
 __printk_ratelimit+0x1c/0x30 kernel/printk/printk.c:4566
 kauditd_printk_skb kernel/audit.c:545 [inline]
 kauditd_hold_skb+0x61/0x1b0 kernel/audit.c:581
 kauditd_send_queue+0x288/0x2e0 kernel/audit.c:766
 kauditd_thread+0x42a/0x650 kernel/audit.c:890
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffffffff88bbdcd8 of 8 bytes by task 15961 on cpu 1:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2301
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2383
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2422
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:68
 _printk+0x7a/0xa0 kernel/printk/printk.c:2432
 ib_get_eth_speed+0x322/0x4a0 drivers/infiniband/core/verbs.c:2006
 siw_query_port+0x3d/0x240 drivers/infiniband/sw/siw/siw_verbs.c:179
 iw_query_port drivers/infiniband/core/device.c:2100 [inline]
 ib_query_port+0x369/0x3a0 drivers/infiniband/core/device.c:2141
 ib_setup_port_attrs+0x148/0x1340 drivers/infiniband/core/sysfs.c:1440
 add_one_compat_dev+0x2e6/0x3e0 drivers/infiniband/core/device.c:975
 rdma_dev_init_net+0x183/0x210 drivers/infiniband/core/device.c:1191
 ops_init+0x1c9/0x260 net/core/net_namespace.c:139
 setup_net+0x14d/0x600 net/core/net_namespace.c:356
 copy_net_ns+0x290/0x430 net/core/net_namespace.c:494
 create_new_namespaces+0x228/0x430 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xe6/0x120 kernel/nsproxy.c:228
 ksys_unshare+0x3c9/0x6e0 kernel/fork.c:3311
 __do_sys_unshare kernel/fork.c:3382 [inline]
 __se_sys_unshare kernel/fork.c:3380 [inline]
 __x64_sys_unshare+0x1f/0x30 kernel/fork.c:3380
 x64_sys_call+0x2c8d/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:273
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000fffff73e -> 0x735f6b746e697270

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 15961 Comm: syz-executor Not tainted 6.12.0-rc5-syzkaller-00181-g6c52d4da1c74 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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