syzbot

==================================================================
BUG: KCSAN: data-race in filemap_fault / generic_write_end

write to 0xffff88810b191708 of 8 bytes by task 11412 on cpu 0:
 i_size_write include/linux/fs.h:886 [inline]
 generic_write_end+0xb1/0x350 fs/buffer.c:2168
 ext4_da_write_end+0x26c/0x620 fs/ext4/inode.c:3175
 generic_perform_write+0x264/0x3f0 mm/filemap.c:3783
 ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:285
 ext4_file_write_iter+0x2bb/0x11b0
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x468/0x760 fs/read_write.c:584
 ksys_write+0xe8/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:646
 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 0xffff88810b191708 of 8 bytes by task 11425 on cpu 1:
 i_size_read include/linux/fs.h:864 [inline]
 filemap_fault+0x82/0x6a0 mm/filemap.c:3130
 __do_fault mm/memory.c:4163 [inline]
 do_cow_fault+0x214/0x5f0 mm/memory.c:4544
 do_fault+0x345/0xaf0 mm/memory.c:4645
 handle_pte_fault mm/memory.c:4931 [inline]
 __handle_mm_fault mm/memory.c:5073 [inline]
 handle_mm_fault+0x8c5/0xb20 mm/memory.c:5219
 faultin_page mm/gup.c:926 [inline]
 __get_user_pages+0x348/0xc20 mm/gup.c:1153
 populate_vma_page_range mm/gup.c:1526 [inline]
 __mm_populate+0x281/0x380 mm/gup.c:1640
 mm_populate include/linux/mm.h:2874 [inline]
 vm_mmap_pgoff+0x160/0x1f0 mm/util.c:525
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1457
 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

value changed: 0x0000000000bde000 -> 0x0000000000be1000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11425 Comm: syz-executor.3 Not tainted 6.2.0-rc5-syzkaller-00013-g2475bf0250de-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
==================================================================