================================================================== BUG: KCSAN: data-race in copy_page_to_iter / fat12_ent_put write to 0xffff8881254f1204 of 1 bytes by task 22723 on cpu 1: fat12_ent_put+0xce/0x180 fs/fat/fatent.c:164 fat_alloc_clusters+0x493/0xab0 fs/fat/fatent.c:502 fat_add_cluster fs/fat/inode.c:108 [inline] __fat_get_block fs/fat/inode.c:155 [inline] fat_get_block+0x267/0x610 fs/fat/inode.c:190 __block_write_begin_int+0x345/0xc70 fs/buffer.c:2006 __block_write_begin fs/buffer.c:2056 [inline] block_write_begin+0x83/0x270 fs/buffer.c:2117 cont_write_begin+0x3bf/0x4f0 fs/buffer.c:2464 fat_write_begin+0x61/0xf0 fs/fat/inode.c:235 generic_perform_write+0x1c8/0x3f0 mm/filemap.c:3792 __generic_file_write_iter+0x195/0x2b0 mm/filemap.c:3887 generic_file_write_iter+0x75/0x130 mm/filemap.c:3951 call_write_iter include/linux/fs.h:2079 [inline] new_sync_write fs/read_write.c:504 [inline] vfs_write+0x755/0x8b0 fs/read_write.c:591 ksys_write+0xd9/0x190 fs/read_write.c:644 __do_sys_write fs/read_write.c:656 [inline] __se_sys_write fs/read_write.c:653 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:653 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881254f1000 of 1024 bytes by task 2342 on cpu 0: instrument_copy_to_user include/linux/instrumented.h:119 [inline] copyout lib/iov_iter.c:154 [inline] copy_page_to_iter_iovec lib/iov_iter.c:226 [inline] __copy_page_to_iter lib/iov_iter.c:852 [inline] copy_page_to_iter+0x427/0x7c0 lib/iov_iter.c:880 copy_folio_to_iter include/linux/uio.h:153 [inline] filemap_read+0xb2f/0xe10 mm/filemap.c:2736 blkdev_read_iter+0x2cc/0x380 block/fops.c:611 call_read_iter include/linux/fs.h:2073 [inline] new_sync_read fs/read_write.c:401 [inline] vfs_read+0x5e2/0x6c0 fs/read_write.c:482 ksys_read+0xd9/0x190 fs/read_write.c:620 __do_sys_read fs/read_write.c:630 [inline] __se_sys_read fs/read_write.c:628 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:628 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 2342 Comm: udevd Not tainted 5.17.0-syzkaller-11406-gf82da161ea75-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================