================================================================== BUG: KCSAN: data-race in data_push_tail / number write to 0xffffffff88e52428 of 1 bytes by task 30 on cpu 0: number+0x8d6/0xab0 lib/vsprintf.c:558 vsnprintf+0x691/0x890 lib/vsprintf.c:2838 vscnprintf+0x41/0x90 lib/vsprintf.c:2939 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2216 vprintk_store+0x599/0x860 kernel/printk/printk.c:2336 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+0x270/0x2c0 kernel/audit.c:766 kauditd_thread+0x421/0x630 kernel/audit.c:890 kthread+0x489/0x510 kernel/kthread.c:464 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read to 0xffffffff88e52428 of 8 bytes by task 29069 on cpu 1: 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 set_capacity_and_notify+0x14c/0x1f0 block/genhd.c:93 loop_set_size+0x2e/0x70 drivers/block/loop.c:210 loop_configure+0x8d3/0xa50 drivers/block/loop.c:1067 lo_ioctl+0x559/0x15d0 drivers/block/loop.c:-1 blkdev_ioctl+0x34f/0x440 block/ioctl.c:704 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:893 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893 x64_sys_call+0x19a8/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:17 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 value changed: 0x0000000100000d70 -> 0x3128746964756120 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 29069 Comm: syz.8.6224 Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ================================================================== vfat: Unknown parameter '0x000000000000041e18446744073709551615' netlink: 4 bytes leftover after parsing attributes in process `syz.8.6224'.