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EXT4-fs error (device loop7): __ext4_get_inode_loc:4830: comm syz-executor: Invalid inode table block 1 in block_group 0
EXT4-fs error (device loop7) in ext4_reserve_inode_write:6298: Corrupt filesystem
EXT4-fs error (device loop7): ext4_quota_off:7270: inode #3: comm syz-executor: mark_inode_dirty error
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BUG: KCSAN: data-race in _prb_read_valid / data_alloc

write to 0xffffffff86887860 of 8 bytes by task 10 on cpu 0:
 data_alloc+0x310/0x390 kernel/printk/printk_ringbuffer.c:1129
 prb_reserve+0x8d7/0xad0 kernel/printk/printk_ringbuffer.c:1724
 vprintk_store+0x53c/0x830 kernel/printk/printk.c:2302
 vprintk_emit+0x15a/0x5c0 kernel/printk/printk.c:2402
 dev_vprintk_emit+0x242/0x2a0 drivers/base/core.c:4914
 dev_printk_emit+0x84/0xb0 drivers/base/core.c:4925
 __dev_printk+0xf3/0x110 drivers/base/core.c:4937
 _dev_info+0x9b/0xd0 drivers/base/core.c:4983
 hid_connect+0xebf/0xef0 drivers/hid/hid-core.c:2338
 hid_hw_start+0x82/0xe0 drivers/hid/hid-core.c:2379
 hid_generic_probe+0x5b/0x70 drivers/hid/hid-generic.c:70
 __hid_device_probe drivers/hid/hid-core.c:2775 [inline]
 hid_device_probe+0x312/0x4e0 drivers/hid/hid-core.c:2812
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x1bf/0x5c0 drivers/base/dd.c:659
 __driver_probe_device+0x121/0x190 drivers/base/dd.c:801
 driver_probe_device+0x37/0x2f0 drivers/base/dd.c:831
 __device_attach_driver+0x205/0x310 drivers/base/dd.c:959
 bus_for_each_drv+0x1c0/0x230 drivers/base/bus.c:500
 __device_attach+0x1c7/0x290 drivers/base/dd.c:1031
 device_initial_probe+0x70/0x90 drivers/base/dd.c:1086
 bus_probe_device+0x101/0x1b0 drivers/base/bus.c:574
 device_add+0x5c9/0x770 drivers/base/core.c:3689
 hid_add_device+0x1b0/0x230 drivers/hid/hid-core.c:2951
 uhid_device_add_worker+0x2b/0xa0 drivers/hid/uhid.c:73
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x582/0x770 kernel/workqueue.c:3421
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

read to 0xffffffff86887860 of 16 bytes by task 32093 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:496 [inline]
 desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1931 [inline]
 prb_read kernel/printk/printk_ringbuffer.c:1979 [inline]
 _prb_read_valid+0x1bc/0x920 kernel/printk/printk_ringbuffer.c:2170
 desc_update_last_finalized+0x8f/0x170 kernel/printk/printk_ringbuffer.c:1570
 prb_final_commit+0x10d/0x150 kernel/printk/printk_ringbuffer.c:1839
 vprintk_store+0x710/0x830 kernel/printk/printk.c:2328
 vprintk_emit+0x15a/0x5c0 kernel/printk/printk.c:2402
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2441
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2451
 __ext4_error_inode+0x2ca/0x3f0 fs/ext4/super.c:853
 __ext4_mark_inode_dirty+0xbd/0x3f0 fs/ext4/inode.c:6476
 ext4_quota_off+0x248/0x290 fs/ext4/super.c:7270
 ext4_quotas_off fs/ext4/super.c:1184 [inline]
 ext4_put_super+0xc5/0x7d0 fs/ext4/super.c:1299
 generic_shutdown_super+0xe6/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1722
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7444
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x2a9/0x320 fs/namespace.c:1318
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1325
 task_work_run+0x131/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
 exit_to_user_mode_loop+0x1fe/0x740 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x1e1/0x2b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 32093 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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