EXT4-fs error (device loop0): ext4_lookup:1787: inode #15: comm syz.0.3870: iget: bad i_size value: 360287970189639690
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BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff88e6b8f0 of 1 bytes by task 4756 on cpu 0:
 string_nocheck lib/vsprintf.c:643 [inline]
 string+0x187/0x220 lib/vsprintf.c:721
 vsnprintf+0x532/0x890 lib/vsprintf.c:2874
 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
 br_set_state+0x28c/0x390 net/bridge/br_stp.c:57
 br_stp_disable_port+0x5d/0x150 net/bridge/br_stp_if.c:106
 del_nbp+0xdc/0x790 net/bridge/br_if.c:343
 br_dev_delete+0x4e/0xe0 net/bridge/br_if.c:386
 br_net_exit_rtnl+0xae/0x120 net/bridge/br.c:380
 ops_exit_rtnl_list net/core/net_namespace.c:182 [inline]
 ops_undo_list+0x1b4/0x410 net/core/net_namespace.c:249
 cleanup_net+0x2de/0x4d0 net/core/net_namespace.c:686
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3321
 worker_thread+0x582/0x770 kernel/workqueue.c:3402
 kthread+0x486/0x510 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 0xffffffff88e6b8f0 of 8 bytes by task 15415 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
 __ext4_error_inode+0x2ca/0x3f0 fs/ext4/super.c:844
 __ext4_iget+0xfb4/0x21c0 fs/ext4/inode.c:-1
 ext4_lookup+0x161/0x390 fs/ext4/namei.c:1787
 lookup_open fs/namei.c:3695 [inline]
 open_last_lookups fs/namei.c:3816 [inline]
 path_openat+0xcf0/0x2170 fs/namei.c:4052
 do_filp_open+0x109/0x230 fs/namei.c:4082
 do_sys_openat2+0xa6/0x110 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1463
 x64_sys_call+0x1af/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:258
 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: 0x00000001000006f5 -> 0x2029315f6576616c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 15415 Comm: syz.0.3870 Not tainted 6.16.0-rc5-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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