EXT4-fs (loop3): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
ext4 filesystem being mounted at /root/syzkaller-testdir1946179936/syzkaller.5hJtYh/298/file0 supports timestamps until 2038-01-19 (0x7fffffff)
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BUG: KCSAN: data-race in data_push_tail / uuid_string

write to 0xffffffff86f490f0 of 1 bytes by task 3081 on cpu 1:
 string_nocheck lib/vsprintf.c:648 [inline]
 uuid_string+0x435/0x4b0 lib/vsprintf.c:1729
 pointer+0x3ee/0xd10 lib/vsprintf.c:2446
 vsnprintf+0x861/0xe20 lib/vsprintf.c:2821
 va_format lib/vsprintf.c:1681 [inline]
 pointer+0x8a1/0xd10 lib/vsprintf.c:2448
 vsnprintf+0x861/0xe20 lib/vsprintf.c:2821
 vscnprintf+0x42/0x80 lib/vsprintf.c:2923
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2128
 vprintk_store+0x56f/0x800 kernel/printk/printk.c:2242
 vprintk_emit+0xd0/0x430 kernel/printk/printk.c:2288
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318
 vprintk+0x83/0x90 kernel/printk/printk_safe.c:50
 _printk+0x7a/0xa0 kernel/printk/printk.c:2328
 __ext4_msg+0x18a/0x1a0 fs/ext4/super.c:937
 ext4_put_super+0x91/0x7f0 fs/ext4/super.c:1290
 generic_shutdown_super+0xd9/0x260 fs/super.c:499
 kill_block_super+0x3b/0x60 fs/super.c:1417
 deactivate_locked_super+0x6b/0xd0 fs/super.c:330
 deactivate_super+0x9b/0xb0 fs/super.c:361
 cleanup_mnt+0x272/0x2e0 fs/namespace.c:1254
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1261
 task_work_run+0x135/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd1/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffffff86f490f0 of 8 bytes by task 14592 on cpu 0:
 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+0x893/0xbc0 kernel/printk/printk_ringbuffer.c:1555
 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2232
 vprintk_emit+0xd0/0x430 kernel/printk/printk.c:2288
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318
 vprintk+0x83/0x90 kernel/printk/printk_safe.c:50
 _printk+0x7a/0xa0 kernel/printk/printk.c:2328
 mnt_warn_timestamp_expiry+0x1bb/0x1f0 fs/namespace.c:2802
 do_new_mount_fc fs/namespace.c:3276 [inline]
 do_new_mount+0x2ee/0x660 fs/namespace.c:3337
 path_mount+0x496/0xb30 fs/namespace.c:3662
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000ffffeea6 -> 0x3030302d30303030

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14592 Comm: syz-executor.3 Not tainted 6.5.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
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