audit: type=1400 audit(1785779691.699:1555): avc:  denied  { read } for  pid=5928 comm="syz.3.745" name="trace_pipe" dev="tracefs" ino=1061 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:tracefs_t tclass=file permissive=1
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BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff893970a0 of 1 bytes by task 5924 on cpu 0:
 string_nocheck lib/vsprintf.c:652 [inline]
 string+0x165/0x220 lib/vsprintf.c:730
 vsnprintf+0x543/0x8c0 lib/vsprintf.c:2945
 vscnprintf+0x41/0x90 lib/vsprintf.c:3014
 printk_sprint+0x30/0x2b0 kernel/printk/printk.c:2222
 vprintk_store+0x57b/0x910 kernel/printk/printk.c:2364
 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2504
 __netdev_printk+0x310/0x370 net/core/dev.c:12972
 netdev_info+0xa6/0xd0 net/core/dev.c:13019
 __dev_set_promiscuity+0x1e5/0x3c0 net/core/dev.c:9620
 netif_set_promiscuity+0x39/0x90 net/core/dev.c:9647
 dev_set_promiscuity+0xb9/0x170 net/core/dev_api.c:288
 macvlan_stop+0x142/0x260 drivers/net/macvlan.c:713
 __dev_close_many+0x24d/0x460 net/core/dev.c:1776
 netif_close_many+0x101/0x2d0 net/core/dev.c:1802
 netif_close+0xe3/0x160 net/core/dev.c:1819
 dev_close+0xb5/0x160 net/core/dev_api.c:221
 bond_enslave+0x1c35/0x2050 drivers/net/bonding/bond_main.c:2377
 do_set_master+0x37b/0x450 net/core/rtnetlink.c:3020
 rtnl_newlink_create+0x435/0x650 net/core/rtnetlink.c:3927
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x1181/0x1400 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x64b/0x720 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x11e/0x220 net/netlink/af_netlink.c:2556
 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:7103
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x5a7/0x680 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x5be/0x6f0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x532/0x580 net/socket.c:2684
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2773
 x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff893970a0 of 8 bytes by task 28 on cpu 1:
 data_make_reusable kernel/printk/printk_ringbuffer.c:608 [inline]
 data_push_tail+0x104/0x440 kernel/printk/printk_ringbuffer.c:693
 data_alloc+0x111/0x380 kernel/printk/printk_ringbuffer.c:1089
 prb_reserve+0x8e3/0xaf0 kernel/printk/printk_ringbuffer.c:1727
 vprintk_store+0x54a/0x910 kernel/printk/printk.c:2354
 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2504
 kauditd_printk_skb kernel/audit.c:588 [inline]
 kauditd_hold_skb+0x1b1/0x1c0 kernel/audit.c:623
 kauditd_send_queue+0x275/0x2d0 kernel/audit.c:808
 kauditd_thread+0x439/0x660 kernel/audit.c:932
 kthread+0x221/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x3fffffffffffe06f -> 0x6c203a34646e6f62

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 28 Comm: kauditd Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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