loop9: detected capacity change from 0 to 512
EXT4-fs error (device loop9): ext4_validate_block_bitmap:441: comm syz.9.15115: bg 0: block 248: padding at end of block bitmap is not set
==================================================================
BUG: KCSAN: data-race in data_alloc / prb_reserve

write to 0xffffffff8668bad0 of 8 bytes by task 15660 on cpu 0:
 data_alloc+0x291/0x2c0 kernel/printk/printk_ringbuffer.c:1096
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:86
 _printk+0x7a/0xa0 kernel/printk/printk.c:2457
 __ext4_error+0x221/0x310 fs/ext4/super.c:830
 ext4_acquire_dquot+0x1d3/0x210 fs/ext4/super.c:6936
 dqget+0x522/0x8b0 fs/quota/dquot.c:977
 __dquot_initialize+0x26d/0x760 fs/quota/dquot.c:1505
 dquot_initialize+0x1a/0x20 fs/quota/dquot.c:1567
 ext4_process_orphan+0x32/0x1c0 fs/ext4/orphan.c:329
 ext4_orphan_cleanup+0x696/0x9e0 fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5610 [inline]
 ext4_fill_super+0x36bb/0x3a10 fs/ext4/super.c:5733
 get_tree_bdev_flags+0x29f/0x310 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5765
 vfs_get_tree+0x56/0x1e0 fs/super.c:1814
 do_new_mount+0x227/0x690 fs/namespace.c:3511
 path_mount+0x49b/0xb30 fs/namespace.c:3838
 do_mount fs/namespace.c:3851 [inline]
 __do_sys_mount fs/namespace.c:4061 [inline]
 __se_sys_mount+0x27c/0x2d0 fs/namespace.c:4038
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4038
 x64_sys_call+0x2c84/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff8668bad0 of 8 bytes by task 15662 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:482 [inline]
 desc_push_tail kernel/printk/printk_ringbuffer.c:778 [inline]
 desc_reserve kernel/printk/printk_ringbuffer.c:924 [inline]
 prb_reserve+0x235/0xb60 kernel/printk/printk_ringbuffer.c:1619
 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:86
 _printk+0x7a/0xa0 kernel/printk/printk.c:2457
 __ext4_error+0x221/0x310 fs/ext4/super.c:830
 ext4_acquire_dquot+0x1d3/0x210 fs/ext4/super.c:6936
 dqget+0x522/0x8b0 fs/quota/dquot.c:977
 __dquot_initialize+0x26d/0x760 fs/quota/dquot.c:1505
 dquot_initialize+0x1a/0x20 fs/quota/dquot.c:1567
 ext4_process_orphan+0x32/0x1c0 fs/ext4/orphan.c:329
 ext4_orphan_cleanup+0x696/0x9e0 fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5610 [inline]
 ext4_fill_super+0x36bb/0x3a10 fs/ext4/super.c:5733
 get_tree_bdev_flags+0x29f/0x310 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5765
 vfs_get_tree+0x56/0x1e0 fs/super.c:1814
 do_new_mount+0x227/0x690 fs/namespace.c:3511
 path_mount+0x49b/0xb30 fs/namespace.c:3838
 do_mount fs/namespace.c:3851 [inline]
 __do_sys_mount fs/namespace.c:4061 [inline]
 __se_sys_mount+0x27c/0x2d0 fs/namespace.c:4038
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4038
 x64_sys_call+0x2c84/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000193720 -> 0x0000000000240490

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 15662 Comm: syz.9.15115 Not tainted 6.13.0-rc7-syzkaller-00043-g619f0b6fad52 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================
EXT4-fs error (device loop9): ext4_acquire_dquot:6938: comm syz.9.15115: Failed to acquire dquot type 1
EXT4-fs (loop9): 1 truncate cleaned up
EXT4-fs (loop9): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
ext4 filesystem being mounted at /297/file0 supports timestamps until 2038-01-19 (0x7fffffff)