loop1: detected capacity change from 0 to 512
==================================================================
BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237d26fd0 of 8 bytes by task 4626 on cpu 1:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x4f0/0x960 fs/buffer.c:1410
 __find_get_block_nonatomic fs/buffer.c:1429 [inline]
 bdev_getblk+0x83/0x3b0 fs/buffer.c:1453
 getblk_unmovable include/linux/buffer_head.h:369 [inline]
 ext4_getblk+0x1b6/0x510 fs/ext4/inode.c:993
 ext4_bread+0x28/0x110 fs/ext4/inode.c:1041
 ext4_quota_read+0xe8/0x260 fs/ext4/super.c:7263
 read_blk fs/quota/quota_tree.c:61 [inline]
 find_free_dqentry+0x133/0x690 fs/quota/quota_tree.c:275
 do_insert_tree+0x537/0x9b0 fs/quota/quota_tree.c:400
 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402
 do_insert_tree+0x753/0x9b0 fs/quota/quota_tree.c:402
 do_insert_tree+0x731/0x9b0 fs/quota/quota_tree.c:402
 dq_insert_tree fs/quota/quota_tree.c:432 [inline]
 qtree_write_dquot+0x2cb/0x300 fs/quota/quota_tree.c:451
 v2_write_dquot+0xda/0x140 fs/quota/quota_v2.c:372
 dquot_acquire+0x1c3/0x2b0 fs/quota/dquot.c:473
 ext4_acquire_dquot+0x15f/0x200 fs/ext4/super.c:6941
 dqget+0x535/0x8d0 fs/quota/dquot.c:980
 __dquot_initialize+0x27f/0x7c0 fs/quota/dquot.c:1508
 dquot_initialize+0x1a/0x30 fs/quota/dquot.c:1570
 ext4_process_orphan+0x32/0x1c0 fs/ext4/orphan.c:325
 ext4_orphan_cleanup+0x6a8/0xa00 fs/ext4/orphan.c:470
 __ext4_fill_super fs/ext4/super.c:5617 [inline]
 ext4_fill_super+0x3483/0x3810 fs/ext4/super.c:5736
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1691
 get_tree_bdev+0x1f/0x30 fs/super.c:1714
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5768
 vfs_get_tree+0x57/0x1d0 fs/super.c:1751
 fc_mount fs/namespace.c:1208 [inline]
 do_new_mount_fc fs/namespace.c:3651 [inline]
 do_new_mount+0x24d/0x660 fs/namespace.c:3727
 path_mount+0x4a5/0xb70 fs/namespace.c:4037
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4215
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4215
 x64_sys_call+0x2b51/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166
 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

read to 0xffff888237d26fd0 of 8 bytes by task 4638 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 smp_call_function_many_cond+0x2a9/0xc60 kernel/smp.c:821
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1043
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1560
 kill_bdev block/bdev.c:90 [inline]
 set_blocksize+0x24f/0x310 block/bdev.c:207
 sb_set_blocksize+0x7a/0x100 block/bdev.c:224
 ext4_load_super fs/ext4/super.c:5123 [inline]
 __ext4_fill_super fs/ext4/super.c:5275 [inline]
 ext4_fill_super+0x146c/0x3810 fs/ext4/super.c:5736
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1691
 get_tree_bdev+0x1f/0x30 fs/super.c:1714
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5768
 vfs_get_tree+0x57/0x1d0 fs/super.c:1751
 fc_mount fs/namespace.c:1208 [inline]
 do_new_mount_fc fs/namespace.c:3651 [inline]
 do_new_mount+0x24d/0x660 fs/namespace.c:3727
 path_mount+0x4a5/0xb70 fs/namespace.c:4037
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4215
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4215
 x64_sys_call+0x2b51/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166
 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: 0xffff88811a4b5000 -> 0xffff888106e83820

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4638 Comm: syz.1.542 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
==================================================================
EXT4-fs (loop1): revision level too high, forcing read-only mode
EXT4-fs (loop1): orphan cleanup on readonly fs
Quota error (device loop1): dq_insert_tree: Quota tree root isn't allocated!
EXT4-fs error (device loop1): ext4_acquire_dquot:6945: comm syz.1.542: Failed to acquire dquot type 1
EXT4-fs error (device loop1): ext4_validate_block_bitmap:441: comm syz.1.542: bg 0: block 40: padding at end of block bitmap is not set
EXT4-fs error (device loop1) in ext4_mb_clear_bb:6667: Corrupt filesystem
EXT4-fs (loop1): 1 truncate cleaned up
EXT4-fs (loop1): mounted filesystem 00000000-0000-0000-0000-000000000000 ro without journal. Quota mode: writeback.