netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'. ================================================================== BUG: KCSAN: data-race in data_push_tail / string write to 0xffffffff87104af0 of 1 bytes by task 27 on cpu 0: string_nocheck lib/vsprintf.c:650 [inline] string+0x16c/0x200 lib/vsprintf.c:728 vsnprintf+0xa09/0xe30 lib/vsprintf.c:2824 vscnprintf+0x42/0x80 lib/vsprintf.c:2930 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2124 vprintk_store+0x56f/0x800 kernel/printk/printk.c:2238 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2284 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2328 kauditd_printk_skb kernel/audit.c:546 [inline] kauditd_hold_skb+0x19d/0x1b0 kernel/audit.c:581 kauditd_send_queue+0x27a/0x2d0 kernel/audit.c:766 kauditd_thread+0x42a/0x640 kernel/audit.c:890 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:243 read to 0xffffffff87104af0 of 8 bytes by task 18738 on cpu 1: data_make_reusable kernel/printk/printk_ringbuffer.c:590 [inline] data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:675 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1046 prb_reserve+0x897/0xbc0 kernel/printk/printk_ringbuffer.c:1555 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2228 vprintk_emit+0xd0/0x5d0 kernel/printk/printk.c:2284 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2328 __nla_validate_parse+0x175f/0x1ce0 lib/nlattr.c:647 __nla_parse+0x40/0x50 lib/nlattr.c:732 nla_parse_nested_deprecated include/net/netlink.h:1325 [inline] __rtnl_newlink net/core/rtnetlink.c:3616 [inline] rtnl_newlink+0x3fd/0x1670 net/core/rtnetlink.c:3751 rtnetlink_rcv_msg+0x80a/0x8c0 net/core/rtnetlink.c:6617 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2543 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6635 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x589/0x660 net/netlink/af_netlink.c:1367 netlink_sendmsg+0x66e/0x770 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x37c/0x4d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x1e9/0x270 net/socket.c:2667 __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b value changed: 0x00000001000060a9 -> 0x3535313438393037 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 18738 Comm: syz-executor.0 Not tainted 6.8.0-rc7-syzkaller-00130-g135288b73cef #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 ================================================================== syz-executor.0 (18738) used greatest stack depth: 9192 bytes left