audit: audit_backlog=65 > audit_backlog_limit=64
==================================================================
BUG: KCSAN: data-race in data_alloc / prb_reserve

write to 0xffffffff86c85e08 of 8 bytes by task 27708 on cpu 0:
 data_alloc+0x31c/0x390 kernel/printk/printk_ringbuffer.c:1130
 prb_reserve+0x8d6/0xad0 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
 __netdev_printk+0x310/0x370 net/core/dev.c:12946
 netdev_info+0xa6/0xd0 net/core/dev.c:12993
 __dev_set_promiscuity+0x1ee/0x3d0 net/core/dev.c:9615
 netif_set_promiscuity+0x39/0x90 net/core/dev.c:9642
 dev_set_promiscuity+0xc1/0x180 net/core/dev_api.c:288
 br_port_set_promisc net/bridge/br_if.c:108 [inline]
 br_manage_promisc+0xf1/0x370 net/bridge/br_if.c:157
 nbp_update_port_count+0xc3/0xe0 net/bridge/br_if.c:242
 br_add_if+0x502/0xa60 net/bridge/br_if.c:627
 br_add_slave+0x2c/0x40 net/bridge/br_device.c:375
 do_set_master+0x390/0x460 net/core/rtnetlink.c:2986
 do_setlink+0x97b/0x2950 net/core/rtnetlink.c:3188
 rtnl_changelink net/core/rtnetlink.c:3800 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3973 [inline]
 rtnl_newlink+0x108a/0x1400 net/core/rtnetlink.c:4110
 rtnetlink_rcv_msg+0x64b/0x720 net/core/rtnetlink.c:6996
 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2550
 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:7023
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x5a8/0x680 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x5c8/0x6f0 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x42e/0x490 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0x76/0x90 net/socket.c:2268
 x64_sys_call+0x2d35/0x3020 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86c85e08 of 8 bytes by task 27812 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:496 [inline]
 desc_push_tail kernel/printk/printk_ringbuffer.c:792 [inline]
 desc_reserve kernel/printk/printk_ringbuffer.c:938 [inline]
 prb_reserve+0x216/0xad0 kernel/printk/printk_ringbuffer.c:1677
 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
 audit_log_lost+0x1cc/0x200 kernel/audit.c:416
 audit_log_start+0x46f/0x730 kernel/audit.c:-1
 common_lsm_audit+0x65/0x230 security/lsm_audit.c:442
 slow_avc_audit+0x14c/0x190 security/selinux/avc.c:779
 avc_audit security/selinux/include/avc.h:131 [inline]
 avc_has_perm+0x144/0x190 security/selinux/avc.c:1198
 selinux_uring_allowed+0x73/0x80 security/selinux/hooks.c:7490
 security_uring_allowed+0x28/0x60 security/security.c:5706
 io_uring_allowed io_uring/io_uring.c:3131 [inline]
 __do_sys_io_uring_setup io_uring/io_uring.c:3139 [inline]
 __se_sys_io_uring_setup+0xe4/0x1e0 io_uring/io_uring.c:3134
 __x64_sys_io_uring_setup+0x31/0x40 io_uring/io_uring.c:3134
 x64_sys_call+0x2962/0x3020 arch/x86/include/generated/asm/syscalls_64.h:426
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000000003c7a8 -> 0x0000000000106158

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 27812 Comm: syz.3.6477 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
==================================================================
audit: audit_lost=1146 audit_rate_limit=0 audit_backlog_limit=64