syzbot

I/O error, dev loop5, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2
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BUG: KCSAN: data-race in _copy_to_iter / copyin

write to 0xffff88816f4ec000 of 4096 bytes by task 24151 on cpu 0:
 instrument_copy_from_user include/linux/instrumented.h:136 [inline]
 copyin+0x67/0x90 lib/iov_iter.c:180
 copy_page_from_iter_atomic+0x429/0xb90 lib/iov_iter.c:817
 generic_perform_write+0x214/0x3f0 mm/filemap.c:3746
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3866
 blkdev_write_iter+0x25f/0x3e0 block/fops.c:541
 do_iter_write+0x494/0x750 fs/read_write.c:861
 vfs_writev fs/read_write.c:934 [inline]
 do_writev+0x256/0x4b0 fs/read_write.c:977
 __do_sys_writev fs/read_write.c:1050 [inline]
 __se_sys_writev fs/read_write.c:1047 [inline]
 __x64_sys_writev+0x41/0x50 fs/read_write.c:1047
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88816f4ec000 of 512 bytes by task 22526 on cpu 1:
 instrument_copy_to_user include/linux/instrumented.h:119 [inline]
 copyout lib/iov_iter.c:169 [inline]
 _copy_to_iter+0x11d/0x8b0 lib/iov_iter.c:524
 copy_page_to_iter+0x333/0x3f0 lib/iov_iter.c:722
 copy_folio_to_iter include/linux/uio.h:169 [inline]
 filemap_read+0x119b/0x1430 mm/filemap.c:2711
 blkdev_read_iter+0x2c6/0x370 block/fops.c:598
 call_read_iter include/linux/fs.h:2181 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3a5/0x560 fs/read_write.c:470
 ksys_read+0xe8/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 22526 Comm: udevd Not tainted 6.0.0-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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I/O error, dev loop1, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2