syzbot

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BUG: KCSAN: data-race in generic_fillattr / generic_write_end

write to 0xffff88810a95a1f8 of 8 bytes by task 4459 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:3096
 generic_perform_write+0x264/0x3f0 mm/filemap.c:3764
 ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:285
 ext4_file_write_iter+0x2c7/0x1170
 __kernel_write_iter+0x157/0x380 fs/read_write.c:517
 dump_emit_page+0x3de/0x830 fs/coredump.c:857
 dump_user_range+0x5e/0x200 fs/coredump.c:908
 elf_core_dump+0x1b1e/0x1c10 fs/binfmt_elf.c:2311
 do_coredump+0xe93/0x1720 fs/coredump.c:755
 get_signal+0x9f9/0xc60 kernel/signal.c:2844
 arch_do_signal_or_restart+0x87/0x2d0 arch/x86/kernel/signal.c:869
 exit_to_user_mode_loop+0x78/0x130 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x69/0x90 kernel/entry/common.c:203
 irqentry_exit_to_user_mode+0x5/0x10 kernel/entry/common.c:309
 irqentry_exit+0xe/0x40 kernel/entry/common.c:412
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570

read to 0xffff88810a95a1f8 of 8 bytes by task 2302 on cpu 1:
 i_size_read include/linux/fs.h:864 [inline]
 generic_fillattr+0x203/0x2b0 fs/stat.c:54
 ext4_getattr+0x37c/0x500 fs/ext4/inode.c:5636
 ext4_file_getattr+0x46/0x170 fs/ext4/inode.c:5647
 vfs_getattr_nosec fs/stat.c:124 [inline]
 vfs_getattr fs/stat.c:161 [inline]
 vfs_statx+0x26b/0x460 fs/stat.c:233
 vfs_fstatat fs/stat.c:267 [inline]
 vfs_lstat include/linux/fs.h:3296 [inline]
 __do_sys_newlstat fs/stat.c:423 [inline]
 __se_sys_newlstat+0x6a/0x270 fs/stat.c:417
 __x64_sys_newlstat+0x2d/0x40 fs/stat.c:417
 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: 0x0000000002319000 -> 0x000000000231a000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2302 Comm: syz-executor.1 Not tainted 6.1.0-rc1-syzkaller-00025-gaae703b02f92-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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