syzbot

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BUG: KCSAN: data-race in _copy_to_iter / fat_set_state

write to 0xffff88810e251025 of 1 bytes by task 3705 on cpu 0:
 fat_set_state+0x16e/0x1e0
 fat_fill_super+0x2432/0x2880 fs/fat/inode.c:1888
 vfat_fill_super+0x30/0x40 fs/fat/namei_vfat.c:1200
 mount_bdev+0x152/0x1e0 fs/super.c:1659
 vfat_mount+0x31/0x40 fs/fat/namei_vfat.c:1207
 legacy_get_tree+0x77/0xd0 fs/fs_context.c:662
 vfs_get_tree+0x56/0x1d0 fs/super.c:1780
 do_new_mount+0x227/0x690 fs/namespace.c:3352
 path_mount+0x49b/0xb30 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3875
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3875
 x64_sys_call+0x25c9/0x2d70 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 0xffff88810e251000 of 1024 bytes by task 3306 on cpu 1:
 instrument_copy_to_user include/linux/instrumented.h:113 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:29 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x126/0xaf0 lib/iov_iter.c:185
 copy_page_to_iter+0x171/0x2b0 lib/iov_iter.c:362
 copy_folio_to_iter include/linux/uio.h:180 [inline]
 filemap_read+0x42c/0x690 mm/filemap.c:2676
 blkdev_read_iter+0x217/0x2c0 block/fops.c:749
 new_sync_read fs/read_write.c:395 [inline]
 vfs_read+0x5e6/0x6e0 fs/read_write.c:476
 ksys_read+0xeb/0x1b0 fs/read_write.c:619
 __do_sys_read fs/read_write.c:629 [inline]
 __se_sys_read fs/read_write.c:627 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:627
 x64_sys_call+0x27e5/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:1
 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

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3306 Comm: udevd Not tainted 6.10.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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