KCSAN: data-race in setattr_copy / vfs_getattr

KCSAN: data-race in setattr_copy / vfs_getattr_nosec (2)
Status: auto-closed as invalid on 2021/07/10 19:21
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 111d, last: 111d

similar bugs (1):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in setattr_copy / vfs_getattr_nosec				3	146d	151d	0/22	auto-closed as invalid on 2021/06/05 13:09

Sample crash report:

==================================================================
BUG: KCSAN: data-race in setattr_copy / vfs_getattr_nosec

write to 0xffff888143804af0 of 2 bytes by task 19 on cpu 1:
 setattr_copy+0x1af/0x1c0 fs/attr.c:247
 shmem_setattr+0xb0/0x450 mm/shmem.c:1118
 notify_change+0x8a3/0xa80 fs/attr.c:398
 handle_remove drivers/base/devtmpfs.c:333 [inline]
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop+0x783/0x8d0 drivers/base/devtmpfs.c:395
 devtmpfsd+0x3f/0x40 drivers/base/devtmpfs.c:437
 kthread+0x1d0/0x1f0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff888143804af0 of 2 bytes by task 8446 on cpu 0:
 generic_fillattr fs/stat.c:48 [inline]
 vfs_getattr_nosec+0x1a5/0x2f0 fs/stat.c:108
 vfs_getattr fs/stat.c:142 [inline]
 vfs_statx+0x128/0x290 fs/stat.c:207
 vfs_fstatat fs/stat.c:225 [inline]
 vfs_stat include/linux/fs.h:3380 [inline]
 __do_sys_newstat fs/stat.c:367 [inline]
 __se_sys_newstat+0x46/0x250 fs/stat.c:363
 __x64_sys_newstat+0x2d/0x40 fs/stat.c:363
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x6180 -> 0x6000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8446 Comm: syz-executor.3 Tainted: G        W         5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci2-upstream-kcsan-gce	2021/06/05 19:18	upstream	9d32fa5d74b1	500c2339	.config	log	report			info	KCSAN: data-race in setattr_copy / vfs_getattr_nosec