KCSAN: data-race in do_mpage_readpage / truncate

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in do_mpage_readpage / truncate_setsize (2) exfat				1	1275d	1275d	0/26	auto-closed as invalid on 2020/11/30 03:17

================================================================== BUG: KCSAN: data-race in do_mpage_readpage / truncate_setsize write to 0xffff88811d59f118 of 8 bytes by task 15993 on cpu 0: i_size_write include/linux/fs.h:894 [inline] truncate_setsize+0x34/0x80 mm/truncate.c:839 fat_setattr+0x7c5/0x810 fs/fat/file.c:536 notify_change+0x82b/0xad0 fs/attr.c:336 do_truncate+0xf9/0x180 fs/open.c:64 handle_truncate fs/namei.c:2887 [inline] do_open fs/namei.c:3233 [inline] path_openat+0x1e51/0x23d0 fs/namei.c:3346 do_filp_open+0x11e/0x1b0 fs/namei.c:3373 do_sys_openat2+0x52e/0x680 fs/open.c:1148 do_sys_open+0xa2/0x110 fs/open.c:1164 ksys_open include/linux/syscalls.h:1386 [inline] __do_sys_creat fs/open.c:1232 [inline] __se_sys_creat fs/open.c:1230 [inline] __x64_sys_creat+0x42/0x60 fs/open.c:1230 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff88811d59f118 of 8 bytes by task 15982 on cpu 1: do_mpage_readpage+0x2ce/0xf70 fs/mpage.c:191 mpage_readpage+0x91/0x110 fs/mpage.c:426 fat_readpage+0x23/0x40 fs/fat/inode.c:210 generic_file_buffered_read mm/filemap.c:2173 [inline] generic_file_read_iter+0xc34/0x14e0 mm/filemap.c:2309 call_read_iter include/linux/fs.h:1901 [inline] generic_file_splice_read+0x2df/0x470 fs/splice.c:313 do_splice_to+0xc7/0x100 fs/splice.c:892 splice_direct_to_actor+0x1b9/0x540 fs/splice.c:971 do_splice_direct+0x152/0x1d0 fs/splice.c:1080 do_sendfile+0x380/0x800 fs/read_write.c:1521 __do_sys_sendfile64 fs/read_write.c:1582 [inline] __se_sys_sendfile64 fs/read_write.c:1568 [inline] __x64_sys_sendfile64+0x121/0x140 fs/read_write.c:1568 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 15982 Comm: syz-executor.5 Not tainted 5.7.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================