loop0: detected capacity change from 0 to 512
==================================================================
BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237c26b70 of 8 bytes by task 8198 on cpu 0:
 bh_lru_install fs/buffer.c:1350 [inline]
 find_get_block_common+0x4f0/0x960 fs/buffer.c:1415
 __find_get_block_nonatomic fs/buffer.c:1434 [inline]
 bdev_getblk+0x7f/0x3d0 fs/buffer.c:1458
 __bread_gfp+0x51/0x250 fs/buffer.c:1520
 sb_bread include/linux/buffer_head.h:348 [inline]
 fat_ent_bread+0xc9/0x1a0 fs/fat/fatent.c:109
 fat_ent_read+0x3ad/0x5a0 fs/fat/fatent.c:368
 fat_get_cluster+0x4b2/0x7b0 fs/fat/cache.c:266
 fat_calc_dir_size fs/fat/inode.c:483 [inline]
 fat_fill_inode+0x4af/0xb00 fs/fat/inode.c:530
 fat_build_inode+0x1bb/0x290 fs/fat/inode.c:608
 vfat_mkdir+0x129/0x1f0 fs/fat/namei_vfat.c:867
 vfs_mkdir+0x210/0x340 fs/namei.c:4359
 do_mkdirat+0x132/0x3f0 fs/namei.c:4392
 __do_sys_mkdir fs/namei.c:4414 [inline]
 __se_sys_mkdir fs/namei.c:4412 [inline]
 __x64_sys_mkdir+0x42/0x50 fs/namei.c:4412
 x64_sys_call+0x2289/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:84
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26b70 of 8 bytes by task 8253 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1556
 smp_call_function_many_cond+0x394/0xb20 kernel/smp.c:838
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1052
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1565
 kill_bdev block/bdev.c:90 [inline]
 blkdev_flush_mapping+0x9a/0x1a0 block/bdev.c:712
 blkdev_put_whole block/bdev.c:719 [inline]
 bdev_release+0x2bf/0x3d0 block/bdev.c:1144
 blkdev_release+0x15/0x20 block/fops.c:660
 __fput+0x298/0x650 fs/file_table.c:465
 fput_close_sync+0x6e/0x120 fs/file_table.c:570
 __do_sys_close fs/open.c:1581 [inline]
 __se_sys_close fs/open.c:1566 [inline]
 __x64_sys_close+0x56/0xf0 fs/open.c:1566
 x64_sys_call+0x2747/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:4
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811598ff08 -> 0xffff8881061cb958

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 8253 Comm: syz.0.1654 Not tainted 6.15.0-rc4-syzkaller-00011-gf15d97df5afa #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
==================================================================
EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
ext4 filesystem being mounted at /309/file1 supports timestamps until 2038-01-19 (0x7fffffff)