rock: corrupted directory entry. extent=28, offset=16056320, size=0
rock: corrupted directory entry. extent=28, offset=16056320, size=0
rock: directory entry would overflow storage
rock: sig=0x4f50, size=4, remaining=3
iso9660: Corrupted directory entry in block 4 of inode 1792
==================================================================
BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff88e56c08 of 1 bytes by task 27275 on cpu 0:
 string_nocheck lib/vsprintf.c:657 [inline]
 string+0x187/0x220 lib/vsprintf.c:735
 vsnprintf+0x532/0x890 lib/vsprintf.c:2926
 vscnprintf+0x41/0x90 lib/vsprintf.c:2991
 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
 __ext4_msg+0x18f/0x1a0 fs/ext4/super.c:981
 ext4_put_super+0x90/0x7d0 fs/ext4/super.c:1286
 generic_shutdown_super+0xe3/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1766
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7395
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1375
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1382
 task_work_run+0x12e/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff88e56c08 of 8 bytes by task 29824 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
 isofs_find_entry fs/isofs/namei.c:102 [inline]
 isofs_lookup+0x8b8/0x930 fs/isofs/namei.c:165
 __lookup_slow+0x190/0x250 fs/namei.c:1808
 lookup_slow+0x3c/0x60 fs/namei.c:1825
 walk_component fs/namei.c:2129 [inline]
 link_path_walk+0x753/0x900 fs/namei.c:2497
 path_lookupat+0x63/0x2a0 fs/namei.c:2653
 filename_lookup+0x147/0x340 fs/namei.c:2683
 user_path_at+0x3e/0x130 fs/namei.c:3127
 __do_sys_chroot fs/open.c:604 [inline]
 __se_sys_chroot+0x45/0x230 fs/open.c:598
 __x64_sys_chroot+0x1f/0x30 fs/open.c:598
 x64_sys_call+0x214f/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:162
 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: 0x0000000100003540 -> 0x662d345458453601

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 29824 Comm: syz.5.8983 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
==================================================================