syz.3.710: attempt to access beyond end of device
loop3: rw=2049, sector=2432, nr_sectors = 516 limit=512
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BUG: KCSAN: data-race in __xa_clear_mark / xas_find_marked

read-write to 0xffff888100688230 of 8 bytes by interrupt on cpu 1:
 instrument_read_write include/linux/instrumented.h:56 [inline]
 __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:84 [inline]
 ___test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:114 [inline]
 node_clear_mark lib/xarray.c:102 [inline]
 xas_clear_mark lib/xarray.c:922 [inline]
 __xa_clear_mark+0xf5/0x1e0 lib/xarray.c:2100
 __folio_end_writeback+0xf4/0x360 mm/page-writeback.c:2971
 folio_end_writeback_no_dropbehind+0x6d/0x1d0 mm/filemap.c:1672
 folio_end_writeback+0x1c/0x70 mm/filemap.c:1698
 mpage_write_end_io+0x245/0x4c0 fs/mpage.c:64
 bio_endio+0x35b/0x3f0 block/bio.c:1819
 blk_update_request+0x33a/0x710 block/blk-mq.c:1016
 blk_mq_end_request+0x26/0x50 block/blk-mq.c:1147
 lo_complete_rq+0x98/0x130 drivers/block/loop.c:314
 blk_complete_reqs block/blk-mq.c:1222 [inline]
 blk_done_softirq+0x77/0xb0 block/blk-mq.c:1227
 handle_softirqs+0xcc/0x2a0 kernel/softirq.c:645
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:1108
 smpboot_thread_fn+0x32f/0x520 kernel/smpboot.c:160
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888100688230 of 8 bytes by task 5811 on cpu 0:
 xas_find_chunk include/linux/xarray.h:1752 [inline]
 xas_find_marked+0x211/0x650 lib/xarray.c:1510
 find_get_entry mm/filemap.c:2087 [inline]
 filemap_get_folios_tag+0xf7/0x400 mm/filemap.c:2354
 __filemap_fdatawait_range mm/filemap.c:523 [inline]
 filemap_write_and_wait_range+0x1f5/0x370 mm/filemap.c:692
 direct_write_fallback+0x73/0x100 fs/libfs.c:2102
 __generic_file_write_iter+0xfd/0x120 mm/filemap.c:4477
 generic_file_write_iter+0x77/0x1f0 mm/filemap.c:4507
 do_iter_readv_writev+0x4f6/0x5a0 fs/read_write.c:-1
 vfs_writev+0x2d3/0x8c0 fs/read_write.c:1058
 do_pwritev fs/read_write.c:1154 [inline]
 __do_sys_pwritev2 fs/read_write.c:1212 [inline]
 __se_sys_pwritev2+0xfc/0x1c0 fs/read_write.c:1203
 __x64_sys_pwritev2+0x67/0x80 fs/read_write.c:1203
 x64_sys_call+0x899/0x2550 arch/x86/include/generated/asm/syscalls_64.h:329
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffffffffe0000000 -> 0xffffff8000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5811 Comm: syz.3.710 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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